Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

Pharmacologic vitreolysis of vitreous floaters by 3-month pineapple supplement in Taiwan: A pilot study
Chi­Ting Horng1,2,4, Fu­An Chen1,4, Daih­Huang Kuo1, Li­Chai Chen1, Shou­Shan Yeh3, and Po­Chuen Shieh1,*12Department of Pharmacy, Tajen University, Pingtung, Taiwan, ROC.
Departmet of Opthalmolgy, Fooying University Hospital, Pingtung, Taiwan, ROC.
3
Kaohsiung City Government, Kaohsiung, Taiwan, ROC.
4
These authors contributed equally to the paper.
*
Corresponding author: Po­Chuen Shieh Ph.D.; E­ mail: h56041@gmail.com

Abstract: Purpose: This survey is the first one in the world to evaluate the pharmacologic effects of pineapples forfloaters. In different designs, we followed the results of patients who took various doses of pineapples each day for 3
months. Methods: The studies and sources of crude pineapples were all scheduled between March and June 2016 in
Southern Taiwan, including Tainan, Kaohsiung and Ping­Tung Cities. The famous, beneficial and delicious
pineapples were supplied by the local farmers selling to the world since 1900. In this study, 388 participants werearranged to undergo a series of ocular examinations during the series of experiments. In experiment 1, 190 subjects
were classified into group 1 (one floater) and group 2 (multiple floaters); all participants took 2 pieces of pineapple
after lunch every day for 3 months. In experiment 2, the 198 eyes with various vitreous floaters were classified into
3 groups by chance, according to the extent of pineapple intake, including the low pineapple group (LPA), middle
pineapple group (MPA) and high pineapple group (HPA). In all the experiments, our staff members cut into one
piece of pineapple with 100 g. Regular intake of pineapples is good for health­promotion and evencancer­prevention; however, to prevent higher blood glucose and ensure daily caloric restriction, the reasonableamount of pineapple is 2­3 pieces within healthy persons. In experiment 2, the amounts of oral pineapples in LPA,
MPA, and HMP were 1, 2, and 3 pieces after lunch each day, respectively. Results: In experiment 1,100% subjectsof one floater (120 eyes) subsides to only 29.2% (35/120) after 3­month­therapy. Besides, 70 participants withmultiple floaters decreased to 19 cases (27.1%; 19/70) three months later. In a world, the extract pineapple may
enhance floaters disappearance. In experiment 2, groups 1­3, (each group = 66 eyes) were choose randomly todifferent supplements including the LAP, MAP and HAP intake also for 3 months. It is surprised that frompineapple may increase the rate of disappearance of vitreous opacity. The percentage of decrease of floaters bytaking the pineapples was 45.5%, 37.8% and 30.2% and 1, 2, 3 pieces, respectively. It also showed that pineapples
for treating the patients with floaters with dose­dependent manner. In addition, the protocols for therapy of thefloaters were no special side effects. Furthermore, the mechanisms of dissolving floaters may be to cut and clear thevitreous fibrils and to scavenge the free radicals which could result in hyaluronic acid degradation and vitreous
floater formation. Conclusion: We found that taking pineapples should diminish the persistence of floaters,posterior vitreous detachment and even extracellular matrixes which could impact the disturbance of vision and evenassociated complications.
[Chi­Ting Horng, Fu­An Chen, Daih­Huang Kuo, Li­Chai Chen, Shou­Shan Yeh, and Po­Chuen Shieh.
Pharmacologic vitreolysis of vitreous floaters by 3-month pineapple supplement in Taiwan: A pilot study. J
Am Sci 2019;15(4):17­30]. ISSN 1545­1003 (print); ISSN 2375­7264 (online). http://www.jofamericanscience.org.
3. doi:10.7537/marsjas150419.03.
Keywords: pineapple, vitreous floater, bromelainbundles, and interconnections between these bundles
allow the formation of an extended network thatmaintains the gel state.
During aging, the vitreous progressivelyliquefies and pockets of liquid form in the gel. In theadult eye, 20% of vitreous is liquid, then after the ageof 40 years there is increasing liquefaction so that by
80 to 90 years of age more than half of vitreous isliquid (1). The vitreous liquefaction, in conjunction
withage­related
weakeningof
postbasal
vitreous­retinal adhesion, then results in posterior

Introduction
The vitreous is highly hydrated gel­like structure(> 98% water) that is acellular, apart from a few cells
called hyalocytes in the vitreous cortex. Besides, thegel state is maintained by a network of long thincollagen fibrils that are approximately 15 nm indiameter. Filling the space is a network of hyaluronan;
this glycosaminoglycan (polysaccharide) may attract
water and generate swelling pressure that inflates thegel. The collagen fibrils are composed of collagentype II, V, XI and IX. They are organized into small

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Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

vitreous detachment (PVD). In clinics, the symptomof PVD is the most common cause of acute­onset
floaters. A recent paper by van Overdam and his
co­workers suggests that patients with isolated PVD,
vitreous floaters, vitreous hemorrhages or retinal
hemorrhages at initial presentation need to berescheduled for a follow­up visit (2). All the persons
were instructed to return if the number of floaters
increased. However, the majority of PVD is benign
regarding physiological change. For those older than
40 years of age, PVD gradually impacts the visual
axis. Moreover, the prevalence of PVD is up to 24%
among those aged 50–59 years, increasing to 87%
among people older than 80 years. In PVD, thevitreous shrinks and detaches from the retina, leading
to floaters. In 14% of cases, tractional forces from thevitreous jelly over the retina sometimes cause retinaltears. However, left untreated, the tears which resultin breakage may allow fluid to enter the sub­retinal
space and could progress to retinal detachment (RD)and even blindness. Therefore, wiping out vitreous
floaters early is very important for eyesightpreservation (3).
Physiologically, the vitreous requires a complex
biochemical and structural procedure. It is completely
attached to the retina. Floaters usually begin as a few
small spots, curtains and clouds, becoming muchdenser over time. In most cases, vitreous opacities
occur as a result of degenerative changes. The
vitreous liquefaction should provoke condensation ofvitreous collagen fibers and PVD which show floaters.
In a more dramatic condition, the existence of floaters
is induced. In humans, most ocular floaters are small
flecks of a protein called collagen in the back of youreye. As you age, the protein fibers that make up thevitreous shrink down to little shreds that clump
together. The shadows they cast on your retina arefloaters. If you further see a flash, it’s because thevitreous has pulled away from the retina. Besides,
posterior uveitis or bleeding in the eye is anotherreason for ocular floaters, which is a serious conditionof the eyes (4). At times, the symptoms of floaters
may occur when patients suffer from high fever, head
injuries or influenza at times and the troublesome
problem should recover spontaneously after two
weeks. However, after aged 40, the vitreous gel
should begin to liquefy involving nearly 50% by age
80, a process called synchysis. When the lysis forms,
the posterior scaffold should detach from the retina
with the intervening space (5). Generally speaking,monocular floaters in patients often reflect someunderlying ocular disease. For example, the major
causes of monocular floaters include: PVD,
vitreomacular traction (VMT) and vitreous
hemorrhage. Additionally, although less likely,
monocular causes of floaters also include

Endophthalmitis, uveitis, vitreous lymphoma, andretinal degeneration. According to past studies, therelationship between ocular floaters and PVD is a
close one. The presence of complete PVD is highly
associated with symptomatic vitreous floaters.
Therefore, it is very important to realize thepathophysiology of the vitreoretinal interface fordetermining how to separate, remove the vitreous
from the retina safely and prevent associatedcomplications such as retinal detachment (RD) andfull­thickness macular holes (FTMHs).
The probability of PVD becoming complicatedby a retinal break or rhegmatogenous RD (RDD) is
influenced by the presence of high myopia, cataract
surgery, peripheral retinal degeneration, trauma,
previous RDD, and a positive family history.
There are several high risks of developing
floaters such as age > 50 years old, nearsightedness,
eye trauma, complications from cataract surgery, eyeinflammation and diabetic retinopathy. Ocular floaters
sometimes may be accompanied with flashes,signifying the possibility of retinal tears, incomplete
detachment or an adhesion of the vitreous body on theinternal
limiting
membrane(ILM),
VMA,
vitreomacular traction (VMT) with separation
between the vitreous and the macula, FTMHs andresulting in retinal detachment. In addition, it
sometimes can increase the macular thickness anddecrease best­correct visual acuity. Therefore, it isvery important to differentiate from the physiologicalcondition to avoid emergent floaters (5).
In this study, we focus on the age­related eyechanges of the vitreous and the vitreous liquefaction;
afterwards, separation from the internal limiting
membrane (ILM) of the retina will happen with theprocess mediated by the aggregation of collagen
fibrils and degeneration of extracellular matrix
component at the vitreo­retinal interface.
In optometry, floaters are the opacities in thevitreous body which cast shadows onto the retina. The
patients see them as small moving spots or specks inthe visual field. Floaters move as the eye moves, but
do not precisely follow eye movements. Whenattempted to look directly at them, the floaters seem tomove away, and blinking does not get rid of them.
They are mostly seen when looking at somethingbright like white paper, plain white or blue sky. The
floaters may appear as various shapes of lines, circles,
dots, cobwebs, clouds, and flies. In our study, someshapes of retinal images were considered as similar
ones. Finally, we counted the numbers of total floaters
as the prognostic factors related to the effectiveness of
pineapple treatment. Following an exact diagnosis, thepatients complaining of floaters were usually managed
conservatively with the reassuring suggestion thatover time they will adapt to the visual axis.

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Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

Traditionally there were two main management
options: pars plana vitrectomy (PPV) or observation.
For the latter, stable mild disease does not justify therisks of surgery, and will resolve spontaneously insome eyes with VMT (6). Even if the spontaneous
resolution of VMT and fibril strands could happen,
more aggressive therapies are indicated for the
possibility of vision loss. Observation may havedisadvantages, with a natural history study reportingthat only 11% of patients’ eyes showed spontaneous
dissociation over a mean follow­up of 5­years,
whereas 64% of eyes lost at least 2 Snellen lines overthis timeframe. In addition, VMT can also progress to
FTMH during observation. However, the patients who
experience persistent or severe symptomology may
undergo PPV. Equally, PPV for VMT may havevarious disadvantages, with only one­third of eyes
gaining 2 or more Snellen lines. Furthermore, PPV is
associated with postoperative patient burden andserious complications such as endophthalmitis andincreased intraocular pressure (IOP) (7). Furthermore,
postoperative retinal detachment occurs in 2.4%, and
92% of phakic eyes are likely to develop cataracts
within 3 years of PPV (8). Some newly techniques,for
instance,
Nd:YAG
laser
vitreolysis,
pharmacological vitreolysis and even 25­gauge
vitrectomy developed (9). For example, Nd:YAG
laser vitreolysis is commonly used in treating thevitreous opacities located near the posterior retina.
Some reports claim that the success rates in existingstudies are highly variable, ranging from 0% to 100%
(10). However, the shock from the Nd:YAG laser
used to break the vitreous floaters may sometimes
damage the human retina and impact the visual loss
(11).
Recently, a new method of enzymatic vitreolysis
with intravitreal ocriplasmin (Jetrea; Thrombogenics
USA, Alcon), which is a recombinant and truncatedform of the human serine protease plasmin has been
employed. Recently, ocriplasmin (microplasmin) is apotential alternative treatment for patients withsymptomatic VMT and macular hole that could also
remove fibril strands and vitreous opacity by pars
plana vitrectomy (12). The ocriplasmin induced thesmaller fragment of the plasmin enzyme and wasapproved as the first non­surgical treatment forpatients with VMT by the Food and Drug
Administration (FDA, USA) in 2012 (13,14). A totalof 26.5% of subjects receiving a single intravitreal
ocriplasmin (125μm) achieved the primary end pointof pharmacologic VMA resolution at day 28
compared with 10.1% of placebo (15). The medical
effect of ocriplasmin is enzymatically degradation of
the protein scaffold in the vitreo­retinal interface andcleave collagen, fibronectin, and laminin which are
the major components of the vitreous strands andfloaters. It may lead to various degrees of vitreousliquefaction and loosening of vitreoretinal attachment
which would decrease the development of epi­retinal
membrane, VMT, and RRD (16), the same idea as theeffectiveness of ocriplasmin for treating the vitreous
body­associated overgrowth tissues (17). The similar
method may be used to cut the extracellular matrices
and clear the useless vitreous fibrils.
How to use the concepts of proteinases, forexample, trypsin, chymotrypsin, papain and somehydrolytic enzymes to dissolve the vitreous strands
and floaters is an advanced option in the future.
Bromelain is extracted from stems and fruits of thepineapple; it contains various proteolytic enzymes
such as anti­inflammatory, analgesics, anti­thrombotic
and antifibrinolytic properties (18). In clinics, it is
now prescribed as the treatment of several diseases,
for example, osteoarthritis, dental pain andpost­operative swelling (19). During our experiences,pineapple may also be a good source of fruit which
would supply hydrolytic enzymes to interact with thevitreous contents and treat patients with vitreous
opacities. Pineapple (Ananas comosus) is a delicious
crown shaped fruit that grows on the tropical plant of
the same name. It is a good source of a number of
essential nutrients, vitamins, minerals, phytonutrients,
antioxidants, etc., and the presence of these nutrientsmakes it a wonderful fruit for our health, skin and hair.
Pineapple is the common name of Ananas comosus
and the leading edible members of the family
Bromeliaceae, growing in the tropical and subtropicalareas including Taiwan, Southern China, Philippines,
Thailand, Indonesia, Malaysia, Kenya, and India.
Pineapple has been used as a medical plant in several
native cultures. Its main component is a sulfhydryl
protease, with traces of acid phosphate, peroxidase
inhibitors and several low molecule weightcompounds.
The stems and fruits from the pineapple containprotease, a particular bromelain, a non­proteolytic
component which is mainly responsible for complete
debridement and dissolving the over­growthconnective tissues, including several proteins andmucopolysaccharide substrates from the human body(20). When we analyzed the proliferative phase in
humans, we found that this event fosters the
production of proangiogenic factors. Vascularendothelial growth factor (VEGF), fibroblast growth
factor 2 (FGF­2), and PDGF2 are initially released byplatelets and then by resident cells. Besides,
endothelial progenitor cells (EPCs) also play animportant role which is mediated by MMP and otherfactors for matrix remodeling and even scar formation(18). Moreover, the protease, including Matrix
Metalloproteinases (MMPs) would be found in thevitreous level in the proliferative diabetic retinopathy,

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which could degrade the ECM and growth factors.
Therefore, we suggest that the autolytic, biological,
and enzymatic factors be used in the biologicalactivities of bromelain in removing vitreous
constitutes and floaters (21).
In this study, we evaluated the effectiveness ofthe pineapple plant to treat patients with ocularfloaters and some VTMs for the restoration of visual
axis and even recovery from the baseline.

were excluded if the signs from the examinations were
not apparent when they subjectively suffered floaters.
The persistence of vitreous floaters from the patients’description and the object findings (focal
echodensities) from the B­scan ultrasonography andophthalmoscopy were all confirmed together.
Ultrasonography provides real­time imaging ofinternal and peripheral vitreous structure, and expands
the evaluation of the patients with floaters (24). Whensubject complaints and the exact diagnosis wereconsistent, the subjects were enrolled in the study. All
288 participants were divided by the number of ocularfloaters as one or multiple (> 1). Therefore, thepatients were all asked to take various pieces ofpineapple, and the time of endpoint study time wasthree months. After they began to eat the pieces ofpineapple prepared by our medical staffs, the patients
returned for a series of check­up examinations every
month. All the crude pineapples were from Southern
Taiwan including Ping­Tung, Kaohsiung and Tainan
and cut open to several pieces (Fig. 1). After weighing,
every piece of the pineapple was mean 100 g. All 388
patients took the pieces of pineapple according tovarious designs. The 190 and 199 subjects wererandomly enrolled in experiment 1 and 2. At first(experiment 1), 190 patients were separated into 2
subgroups: one floater and multiple floaters (> 1) inexperiment 1. Secondarily (experiment 2), 199
subjects with one or multiple floaters would be
divided into 3 subgroups randomly, and they received
various (low, middle, high) treatments in theexperiment 2. When the floater numbers decreased,
the positive findings were confirmed as successful
therapy. Afterwards, we compared the results of thepineapples to the treatment of the ocular floaters inexperiments 1 & 2 before and after 3 months.
The schedule was between 2016 March with
June in 2016 for heidig the “bright: survey about theconcent for treating ocular floaters, which was anincurable disease in the past decade. All 388
participants were arranged to undergo a series ofocular examinations. The whole study was completed
in 3 months and we compared with the outcomes after
3­month supplement. In fact, the bromelain was
obtained from the stem or fruit of the pineapple. It issold in the form of a powder, cream, tablet, or capsule.
In our study, we directly cut the whole pineapple into
several pieces horizontally; each piece may containstems and fruits. In experiment 1, the 190 participates
were separated to one floater (group 1) and multiple
floaters (group 2). Hence, all 190 subjects were asked
to eat 2 pieces of pineapple every day prepared by ourstaffs. In experiment 2, 198 patients with 198 eyes
were placed in 3 subgroups: low pineapple group(LPA), middle pineapple group (MPA) and highpineapple group (HPA) for various pieces of the

Methods and Materials
This institutional review board (IRB) approved
this retrospective study, which included 388
consecutive eyes of 388 patients complaining about
floaters in Southern Taiwan. This study followed thetents of the Declaration of Helsinki. Moreover,patients were included if they were at least 18 years ofage and did not suffer from the ocular floaters after
trauma or major disorders within 6 months. The
reason is that some medical reports demonstrate thatquick liquefaction occurred, and the inner contents
should result in changes after trauma or otherdisorders. Interestingly, in experiment 1, when theseocular images of high conscious subjects mentioned atleast 1 image interpreter, the diagnosis of vitreous
opacities, PVD and some symptomatic SMV subjects
were confirmed by indirect ophthalmoscopy, B­San(ultrasonography) and spectral domain opticalcoherence tomography (SD­OCT) of all participants(22). Ultrasonography is routinely used to diagnose
PVD and vitreous floaters, because of theircharacteristics of dense collage matrix. Besides, OCTs
allow detailed imaging of the transverse and coronal
aspects of the vitreoretinal interface. It may also easily
and clearly detect the vitreous floaters. Therefore, adilated examination of the ocular fundus is mandatory,
so only patients with stable and solid vitreous opacityand PVD were enrolled in our experiment. However,the floaters forming blood clots or unexpected
incomplete PVD were all excluded in our experiments(23). Besides, all the systemic diseases; hypertension,DM, hyperglycemia and connective tissue disorders
may impact the normal physiological PVD. Moreover,age, and lens status showed significantly positive
impact on floaters. The vitreous hemorrhage inproliferative
retinopathies
include:diabetic
retinopathy, sickle cells, venous occlusion, Eales
disease, intraocular inflammation, trauma surgery,asteroid hyalosis (AH), as well as myopia (highmyopia > 8D). The above were excluded from ourstudy because of the complicated vitreous­retinal
pathophysiology.
Any similar shadow shapes of floaters wereconsidered as one image. In addition, those withocular floaters greater than one image were includedin the group of patients with multiple floaters. Patients20

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

designed supplement. Taking too much pineapple isharmful to DM patients as it may elevate the glucose
level in the blood, so the maximal amount of thepineapple in our experiment is eating 3 pieces (about
300 g) each day, which is safe. Therefore, we
designed for 2 pieces of pineapples (around 200
mg/day) for the management strategies for everybody
in experiment 1. Besides, in experiment 2, all 199
patients were divided to 3 subgroups and received
various doses treatment: the low­, middle­, andhigh­dose pineapples (LDP, MDP, HDP; 1, 2, 3 pieces,respectively). Afterwards, we compared the outcomesof the pineapples to the treatment of ocular floaters
after the 3–month treatment. In experiments 1 and 2,
the participants all took the pineapple after the lunch.
Besides, all subjects were arranged to return to receivea series of examinations to follow their ocularcondition every month.
All patient charts were reviewed for age, gender,
lens status, chief complaint, number of ocular floaters,
any discomfort, and side effects. Besides, all the data
were measured and the statistical differences were
measured for the effect of pineapples with the use of
SAS 9.0 (SAS Inst., Cary, NC, USA). The P value <0.05 was considered statistically significant.

discomfort or side effects from the pineapple
supplement. The definition of the case “success” isthat the floaters and retinal shadows were no longer
visible by indirect ophthalmoscopy and even SD­OCT
detection. Besides, some of the participants told usthat they could see the scene beautifully without black
image blacking after 3 months.
In experiment 1 (2 pieces /day for every one), thepercentage of 120 patients with one floater
successfully disappeared decreased to only 35 subjects(29.2%; 35 /120) (P < 0.05). Besides, 70 patients withmultiple floaters decreased to only 19 patients (27.2%;
19 /70) with regular supplement of pineapples for 3
months (P < 0.05) (Table 1).
In experiment 2, the final results of various
floaters in the 3 groups with LPA, MPA, and HPA
treatment were compared after they took different
doses of pineapple for 3 months. Firstly, we foundthat 66 patients with LPA treatment taking one pieceof pineapple every day in subgroup 1 decreased to 33
subjects (45.5%; 30/66) after 3 months (P < 0.05).
Secondly, 66 participants with MPA treatment taking
two pieces of pineapple every day in subgroup 2significantly decreased to 22 subjects complaining
about decreased shadow of retinal image (33.3%;
25/66) after the whole 3­month­peroid therapy (P <0.05). In subgroup 3, 66 patients were asked to take 3
pieces of pineapples each day. Three months later, thepatients with lower floaters dramatically changed to
17 patients (25.8%; 17/66). During the series of
examinations, we found that the vitreous opacity had
improved without further blocking the visual axis
(Table 2). Furthermore, it is reported that the greater
amounts of pineapple taken, the fewer the patients
retaining vitreous opacities and floaters. According to
the maximal doses of pineapple supplement, thegreater the effectiveness in treating floaters andenhanced vitreous opacity showed lysis. In summary,treating the patients with ocular floaters by pineapple
supplements revealed the dose­dependent manner. It
was interesting to find that the patients with floaters
during a 3­month­peroid therapy were 45.5%, 33.3%
and 25.8% and 1, 2, 3 pieces of pineapple,
respectively. We concluded that pineapple intake may
decrease the aggregation of collagen fibrils forming
fibers and the rates of symptomatic floaters.
Furthermore, we suggest that bromelain isadvantageous over the firm PVD easily separated
from the vitreo­retinal interface. Therefore, pineapple
supplement is good for the patients with various
floaters.

Fig. 1. The pineapple is abundant in Taiwan. In ourstudy, the whole pineapple would be divided into
several pieces to treat the patients with ocular floaters.
Results
In the whole study, no retinal damage or ocularinflammation was observed. Besides, the intraocularpressure and blood sugar of all the participants werenormal. The vision of all the participants remained
stable and the angle of chamber, lens status corneal
and zonular fibers all showed normal by means of aslit lamp (SL­D7; NIDEK) and anterior segment OCT(Heidelberg OCT) (25).
Furthermore, no participants suffered any

Table 1: The change of various floaters before and after eating over a period of 3 months
Ocular floater numbers
Before
1st month
2nd month
3rd month21

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One
120
119
88
35* (29.2%)
Multiple70
6852
19* (27.1%)
N= 190 eyes
1. Multiple floaters denote patients with at least 2 floaters.
2. After treatment, the patients with multiple floaters may completely or incompletely disappear. Therefore, themultiple floaters would change into 1 or 0 floaters.
*3. We compared the results at the basal time and 3 months by ANOVA. If p value is less than 0.05, it showedsignificant difference.
Table 2: The change of ocular floaters before and after taking pineapples over a period of 3 months
Numbers of pineapple
Before
1st month
2nd month
3rd month
1 pieces66
66
54
30* (45.5%)
2 pieces66
66
56
22* (33.3%)
3 pieces66
60
58
17* (25.8% )1. Group 1 (N= 66 eyes): the patients took 1 piece of pineapple
Group 2 (N= 66 eyes): the patients took 2 pieces of pineapple
Group 3 (N= 66 eyes): the patients took 3 pieces of the pineapples*2. We compared the results at the basal time and 3 months by ANOVA. If the p value is less 0.05, it showedsignificant difference.
The onset of floaters is often secondary to PVD
and possible complications. When patients complain
about floaters, they should be referred to special
ophthalmologists for detailed examination to exclude
the more peripheral region of retinal tear or
detachment. Moreover, the physicians should identify
the possible “vitreous floaters’ as their urgent
approach. According to previous studies, acute onsetof floaters and even PVD would develop into theretinal break within six weeks. However, early
diagnosis and possible treatment for the floaters and
PVD becomes very serious.
The nature and composition of the vitreous
humor change over the course of life. In adolescence,the vitreous cortex becomes denser and vitreous tracts
develop; in adulthood, the tracts become better
defined and sinuous. Central vitreous liquefies,
fibrillar degeneration occurs, and the tracts break up.
The coarse strands develop with ageing. The gel
decreases with age and the liquid volume increases.
Cortex may disappear at sites, leading to liquid
vitreous extruding into the potential space between thevitreous cortex and retina. Therefore, vitreous floaters
may be the symptoms or signs of people leading to theghosts of blindness by the side (26). A follow­up visit
for patients with an isolated PVD or floaters can bejustified to detect the small percentage ofasymptomatic retinal breaks.
Vitreous opacities may affect patients at any age
whereby they experience eye floaters. Most floaters
are small spots that drift through the field of humanvision. Moreover, they may stand out when they lookat something bright, like white paper or a blue sky.
Visual floaters are visual phenomena caused bydegenerative changes of the vitreous gel. Over time,the vitreous collagen type IX decreases, resulting inthe surface exposure of “sticky” type II collagen.

Discussion
Vitreous is a dilute meshwork of collagen fibrilsinterspersed with extensive arrays of hyaluronanmolecules. Besides, hyaluronan is the major
macromolecules of vitreous which is an unbranchedpolymer of repeated disaccharides linked byglycosidic bonds in physiology. Moreover,hyaluronan is also covalent to a protein core; theensemble is called proteoglycan. Further analysis
showed vitreous contains collagen type II, a hybrid oftype V/XI, and IX collagen in a molar ratio of 75:10,
15, respectively. The vitreous collagens are organized
into fibrils, with type V/Xi residing in the core, type II
collagen surrounding the core, and the IX collagen on
the surface of the fibrils.
In anatomy, vitreous consists of hepatocytes,
collagens (type I, IX, V/XI and VI collagens), GAGs,
PGs, and other extracellular matrix molecules(fibrillin. Optcin, VIT­1). The collagen molecules arecoiled by three α polypeptide chains coiled into aleft­hand helix. The three chains then warp aroundeach other into a right amino acid, which is a
glycine­residual that creates Glycine­X­Yn aminoacid repeat. The X­and Y­repeats can be any aminoacid, but X is often alanine or proline, and the Y is attimes hydroxyproline. Besides, collagens are also richin lysine. All collagens have non­triple­helical region
bonds and stabilize the structure of the collagen triple.
Hydroxyproline forms hydrogen bonds and stabilizes.
The lysine and hydroxylysine residues are necessary
for the flotation of intramolecular cross­link, which
stabilizes the collagen fibrils. Hydroxylysine also
provides potential sites for posttranslational
glycosylamines. To date, nearly 30 different types ofcollagen molecules for more than 40 genes have beencharacterized. Interestingly, vitreous collagens
resemble collagen fibrils.

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Hence, these result in the vitreous collagen fibrils
aggregating and liquefying, while accompanied
vitreous shrinkage and clumping make tiny shadowson the retina (27). The PVD entails the collapse of thevitreous body and anterior displacement of theposterior vitreous cortex, and is the most common
cause of floaters. The symptoms might annoy somepeople and shouldn’t interfere with their eyesight.
However, the floaters sometimes may impair theability to read, use the computer and smartphone, anddrive. The impact is more challenging for some highdetail visual requirements, particularly in dynamic
settings, for instance performing from sheet music. Iteven appears in the peripheral vision, giving thesensation of people approaching from behind or fromthe side. Efforts to temporarily alleviate visualinterference include eye blinking, rubbing eyes,closing one eye, or moving the head. These
maneuvers only give short windows of visual clarity.
Vitreous floater symptoms usually subside with thepassage of time; however, some patients with floaters
may suffer from persisting discomfort, andpsychological distress; they then seek medical care.
Hence, the constant struggle to achieve adequate
visual transparency for some peoples impacts theiremotional and physical resilience as well (28).
Interference of the floaters with the visual axis resultsin patients’ discomfort. Besides, the contrast
sensitivity may decrease to 67% starlight increase ineyes which would induce unhappiness (29). Recent
studies indicate that vitreous floaters can have asignificant negative impact on visual function and inturn the quality of life (30). Although in most patientsthe floaters are minimal, they can cause various
significant impairments in the vision­related quality oflife, affecting a small population of patients. Now, a
new definition of floaters as “symptomatic vitreous
opacities (SVO)” was further made. Ivanosva et al.
conclude that the SVO could also lead to intermittent
blurred vision, glare and even haze attributable tomigration of vitreous opacities into the visual axis.
This event interferes with many important activities ofdaily life such as reading, driving, and performing
close work (31). Wagle and his co­workers reported
that patients with floaters and PVD were willing totake an 11% risk of death and a 7% risk of blindness
just to get rid of the bothersome floaters due toimpaired driving (30). Therefore, determining how todecrease the numbers of vitreous floaters has become
an important issue. Besides, they also raise thedemand for healthcare for ophthalmic professionals
and extend the range of their service provision (32).
The vitreous liquefaction destabilizes collagen
fibrils at the age of 4 years, and 12.5% of the vitreous
is liquefied at the age of 18. The most common
etiologic cause of floaters is age­related andmyopia­induced liquefaction of the vitreous gel;liquefaction induces collagen into visible fibrils andleads to the collapse of the vitreous body. According
to further research, most macromolecules in vitreous
are collagens II and collagens IX, glycosaminoglycans(GAGs) like hyaluronic acids (hyaluronan; HA),
proteoglycan
(PGs)
and
non­collagenous
glyco­proteins. Because water may bind to HA, theageing process could lead to two structural changes:(1) depolymerization of HA which causes water
structural changes and (2); loss of collagens IX which
provokes aggregation of collagens II fibrils andfurther leads to the formation of fluid filled withlacunae. Therefore, collagen filament aggregation andcondensation result in the formation of larger fibrils,
which float in lacunas of liquefied vitreous giving thepatients the perception of floaters. The speed at whichthese vitreous changes happen depends on thepeople’s age, environmental factors, exposure to
sunlight, oxidative stress, and HA­collagen interaction.
As for age, among patients > 70 years old, we findthat at least 50% of the vitreous is liquefied. In
summary, the floaters do not impact the human visualacuity; and the numbers sometime increase with age.
In youth, the vitreous is a clear gel that fills thevitreous cavity, occupying approximately 80% of thevolume of the globe, so called “myopic vitreopathy”.
In nature, the vitreous consists mostly of water (99%)
as well as hyaluronic acid and a meshwork of finecollagen fibrils. An important area is the vitreous base,a 3­ to 4­mm­wide circumferential zone of vitreousthat straddles the ora serrata. In the vitreous base, thecollagen fibers are firmly attached to the underlying
peripheral retina posterior to the ora serrate, and to thepars plana epithelium anteriorly. Other areas of firm
vitreous attachment are at the edges of retinal scars, inareas of lattice and other vitreoretinal degenerations,at the optic disc, and along the major vascular
arcades. The prevalence of PVD increases with age,
axial length, and following cataract surgery andtrauma. Vitreous floaters are a part of the PVD inclinic. Some articles demonstrate that myopic people
should experience floaters and PVD approximately 10
years earlier than those with emmetropia or hyperopia.
Besides, human lens removal allows hyaluronic acidto diffuse more easily out of the vitreous into theanterior chamber and subsequently out of the eye. The
unsupported
collagenfibersthencollapsetogether. Indeed, the posterior capsule may induce aneffective barrier to hyaluronic acid, and the procedureof posterior capsulotomy may easily enhance floaters
and possible PVD. This event occurs as a result ofliquefaction. With increasing age, an opening
ultimately develops in the posterior vitreous throughwhich the central liquefied vitreous passes suddenly
into the retro­vitreous space, rapidly dissecting a plane

23

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

and separating the posterior hyaloid from the retina.
Furthermore, floaters and PVD are involved asinciting events in most cases of RRD (33). Typicalsymptoms of PVD are floaters which are described as
cobwebs, spots or hair in the field of vision; they arecaused by vitreous opacities, for instance, theperipapillary glial tissues torn from the optic disc,condensations of vitreous collagen, and/or blood.
However, acute symptomatic retinal breaks resulting
from severe PVD have a high risk of RD with visualloss. Moreover, incomplete PVD may also induce theformation of VTM. If left untreated, partial VTM may
improve through spontaneous resolution; however,some patients unfortunately experience deteriorationin their vision. Therefore, removal of vitreous floaters
becomes the mainstay treatment in the unexpecteddevelopment of ocular diseases.
Current treatment options for vitreous opacity,
PVD, and symptomatic VMT in patients include:observation, pneumatic vitreolysis, Nd:YAG laser
vitreolysis, pars plana vitrectomy and nearly
developing pharmacologic vitreolysis. At first, close
observation by the experienced ophthalmologists at aregular time indicates if the patients with limited
vision are relatively too young or too old to treat.
Indeed only a close follow­up is certainly a reasonable
initial approach, as the progress of VMT is known tospontaneously ease in some patients. Therefore, earlypreservation of the human body and even ophthalmic
acuity is very important. The VMA always develops
when the traction forces exerted on the area ofadhesion are sufficient to produce anatomical
distortion of the macula, resulting in severe VMT andeven FTMHs formation. The symptoms and signs ofpatients with VTM and FTMHs include ocularfloaters such as metamorphopsia, visual acuity
changes, lower contrast sensitivity and central visual
fields defects. As for the timing of operation, in Japan,
most vitreo­surgeons favor emergent operation until
observation when the patients’ best­corrected visualacuity drops to 6/30 (12).
Patients with vitreous floaters and mild PVD canreceive close follow­up. Although almost all patients
accept the conservative management option, there is asmall subset of patients who may desire moreaggressive treatment intervention to resolve theirvisual symptoms (21). However, if they do notspontaneously relieve, aggressive treatment, including
surgery should be taken into consideration. For
example, vitrectomy is indicated for the common
choice. Till today, various methods were arranged totreat the vitreous floaters: complete or incomplete
PVD, and symptomatic VMT. Vitreous floaters are acommon complaint in the ophthalmic care setting.
However, most conditions are benign, so ophthalmiccare practitioners have little to offer regarding

treatment options. The majority of cases encounteredare managed with patient education and reassurance.
Now, there are several therapies in solving the above
vitreous problems including vitrectomy, pneumatic
vitreolysis,
Nd:YAG laser
vitreolysis,
andpharmacologic vitreolysis (34).
Pars plana vitrectomy is an effective treatment
for the surgical removal of the vitreous opacities,
incomplete fibril strands, firm VMA, symptomatic
VMT and even FTMHs until 1991. Some surgeons
even use the gas tamponade (SF6 or C3F8) for as longas possible in an attempt to enhance closure rates.
Kelly and Wendel postulate that vitrectomy would
remove traction around the hole and this, combinedwith gas tamponade, would result in the ring ofperifoveal detachment flattening with some (58%)
improvement of vision (35). There is a relationshipbetween these two choices: gas choice andpostsurgical requirement, related to the amount oftime of time that gas still bridges the severe VMT or
holes. The combined gas (air­fluid exchange) could
cross the defect of a macular hole without face­down
positioning in an upright position; if the gas fillexceeds 50%, a long­acting tamponade will maintain>50% gas fill for a longer time than air or short­acting
gases. Unfortunately, vitrectomy could also carrysignificant surgical risks, including cataract, glaucoma
and RD, which may limit the broad indication ofvitrectomy for floaters (36).
As for the method of pneumatic vitreolysis(PVL), the small quantity of expansible gas is injected
into the vitreous cavity to achieve focal VMT releasefor eyes with symptomatic VMT. The method ofpneumatic vitreolysis since 1993 is the intravitreal
injection of a small quantity of expansible gas for the
purpose of achieving focal VMT release for eyes withfloaters, VMT, or inducing VMT release and closureof macular defect. The success rates of VMT release
have ranged from 60% to 100%, and the rates ofclosure of small macular holes have ranged from 50%
to 80% following PVL, which is a promising,low­cost therapeutic option, with the potential for
managing symptomatic VMT and vitreous floaters on
a global scale. The intravitreal special gas (i.e.: C3F8)
bubble creates an intragenic PVD that relieves VMT
in some patients. However, the success rates of VMTrelease range broadly. Besides, the danger of
intravitreal injection includes: intragenic cataract,
glaucoma, Endophthalmitis, retinal breaks, and thedevelopment of RD (37).
Nd:YAG laser vitreolysis is attractive because itis relatively simple and effective for treating the mid­,posterior floaters and even Weiss ring floaters (38).
The mechanism of laser vitreolysis would be used forthe lysis of fibers and rhexis of aggregates, followedby displacement out of the visual axis which could be24

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

offered to treat symptomatic vitreous floaters.
Recently, this method has been widely used tocollagenous vitreous strands, transvitreal sheets orbands, and mostly to break the vitreous opacities. Thisis generally performed by focusing the laser onto thevitreous opacities visible at the slit­lamp. Typically,
only opacities relatively far from the retina are treated,
thus, these represent a subset of floaters that might beappropriate to treat with Nd:YAG laser. Unlike
vitrectomy, the laser is closed eye obviating the risk ofendophthalmitis, rapid progression of cataracts,
elevated intraocular pressure leading to glaucoma,posterior capsule defects, retinal tear or hemorrhage
and even severe RD. This non­aggressive alternative
method is more dedicated and safer than vitrectomy.
Therefore, amorphous floaters in the mid­ to posterior
vitreous are clinically significant and difficult tovisualize and treat by Nd:YAG laser.
Medical therapeutic treatment evolved fromsurgery to pharmacotherapy and then to prevention asa result of increased knowledge about the origin andpathophysiology of diseases. The treatment ofvitreo­retinal diseases is currently undergoing the firststage of this paradigm shift with development ofpharmacologic vitreolysis. Hence, the concepts ofproteolytic and collagenotic enzymes attempt toremove and dissolve of burn or traumatic eschar andproliferative tissues for years. It is interesting to findthat the stem of the pineapple plants also contains a
number of protease (particular bromelain) andnon­proteolytic component enzymes (for the complete
debridement of burns). Current options show thedecreased vitreous cells and proliferative tissues.
Therefore, intravitreal injection with Ocriplasmin is apotential alternative therapy for floaters, and VMT.
The enzymatic activity of ocriplasmin at thevitreoretinal interface facilitates release of VMT insome patients and must simultaneously liquefy the gelliquid and weakening the VMA. A randomized,
controlled trial (called MIVI­TRUST) examined theuse of ocriplasmin for pharmacologic treatment of
VMT in 652 eyes. Stalmans et al. reported that thesuccess of traction release was achieved at 26.5% on
day 28, significantly better compared with only 10.1%
in the control group. The vitreous floaters and VMTare the pathologic consequence of vitreous attachmentwith structure disturbance of retina which would be
successfully dissolved by ocriplasmin (22). Grandorf
et al. report dose­ and time­dependent cleavage byocriplasmin between posterior vitreous cortex and theILM in both human cadaver and feline eyes (38).
Recently, ocriplasmin is even considered ascost­effective in patients without epiretinal membraneor full thickness macular hole which is useless toutilize vitreolysis and absorbing the extracellularmatrix and proliferative tissues such as vitreous

floaters (so called vitreous balls).
The reason for sudden onsets in patients 50 years
or older has been related to PVD in 95% cases.
Furthermore, in the pathogenesis of PVD, after
vitreous liquefaction, the second most important eventis the age­related weakening of the adhesions between
the posterior hyaloid membrane and the internal
limiting membrane, which leads to the separation ofthese two structures, shrinking and collapse of thevitreous body) (39). In patients with high myopia,
vitreous liquefaction, floater liquefaction floaters­
related PVD occurs much earlier compared to thesame age patients, with emmetropia or hyperopia (40).
Early vitreous liquefaction and PVD describe ion
conditions following trauma, phakia, intraocularinflammation, vitreous hemorrhage and retinal venous
diseases (41). During ageing, the vitreous degenerates
in time, collapses and detaches from the retina, which
may induce complete or incomplete PVD. The mostcommon complications of age­related total PVD are
retinal tear; vitreous, retinal, and optic­dischemorrhage; as well as RDD.
Because the association between vitreous
floaters and PVD is very close, it is very important torealize the epidemiology. In patients with acute onsetof floaters as a consequence of PVD, the incidence ofthe retinal tear 14.5% and that of vitreous and/or
retinal hemorrhage is 22.7% (42). Besides, visual
impairment was found to be a predictor for retinal
pathology, which is in accordance with previous
studies where 67% of patients with decreased visualacuity had retinal tears or detachments, whereas 19%
of patients with floaters or flashes alone had these
conditions (22). A previous study showed floaters in
42%, flashes in 18%, and both floaters and flashes in
20% of PVD and secondary retinal pathology. The
incidence of retinal rupture increased from 4%–5%with only floaters to 10%–11% with flashes
with/without floaters. However, floaters alone should
not be discarded as unimportant; 26.7% of the retinaltears or RD occurs with floaters alone. It has beenshown that PVD usually occurs in the other eye within
6 months to 2 years after the first eye (19). It is likelythat PVD is a parallel process in both eyes; thus, thepatient should be informed of possible pathologies not
only in the eye with the present pathology but also in
the other eye as well. Hence, the presence of a retinal
tear should trigger special attention to the retinal
status of such patients in the future. Therefore, we had
better approach the floaters when they happen, eventhough some of them indicate waiting.
Besides, patients with uncomplicated PVD havea 3.4% chance of rapid retinal tear within 6 weeks.
However, it could reveal floaters shown forprevention from doctor and permanent vision loss ifleft untreated (42). Hence, early quantifying of the25

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

association between relevant clinical variables andrisk of retinal tear in patients presenting acute­onset
floaters and its treatment becomes very important.
According to Byer’s study, the prompt andconscientious vitreo­retinal examination of eachpatient older than 45 years of age who experiences
vitreous floater is the most effective way forpreventing RRD. Of 163 patients who had one to two
floaters as their presenting symptom, with or without
light flashes, the retinal tear should develop in 7.3%of total patients. Therefore, Byre concluded that inthis early floaters stage when the symptom was
detectable, it is crucial in terms of providing an
opportunity for early treatment of vitreous floatersthat might prevent RD formation (43). Furthermore,
Dayan and his colleagues also report that retinal tear
may be found in 26.7% of patients with PVD
presenting floaters alone. In their study, 295 patientswith floaters were reviewed: 64% had only isolated
PVD (the most common), 16.6% had DR and 31%
had flat retinal tear. They further commented thatfloaters were predictors of vitreo­retinal pathology(26). Sharma and his co­workers found that vitreous
floaters are the presenting symptoms of patients with
PVD­related cases, flashes in 62% and both in 51% ofcases within duration of less than 1 month (44). Now,
due to the overuse of computers and smartphone, thecase of condition of pre­mature cataracts, PVD andvitreous floater are increasing. PVD is even more
accelerated after cataract surgery and 75.8% eyes
without preoperative PVD or lattice degeneration
showing higher incidence of RD after cataract surgery
were noted. Furthermore, the incidence of RD withpost­operative
PVD,
uneventfulforphacoemulsification was 21.2%. The onset of
postoperative PVD should be considered an importantrisk factor for the development of RD after cataract
surgery, particularly in eyes with lattice areas. We
collected all the results and concluded that patientswith vitreous floaters or any fibril strands should
arrange a series of management according to theamounts and location of the “trouble” vitreous
opacities (45).
In the past, observation was deemed a negative
concept because of the advanced vitrectomy
techniques which could easily remove vitreous
collagen and hyaluron with smaller instruments.
Current surgical techniques are sutureless because
highly shelved small gauge sclerotomies areself­sealing, obviating the need for sutures. Aspiration
setting and cut rates are the same as typically used for
vitrectomy, that is, between 400 and 600 aspirations
and 1800 to 2500 cuts per minute. The amount ofvitreous removed varies from extensive with surgicalinduction of PVD, to limited without PVD induction
and with preservation of 3 to 4 mm of retrolental

vitreous. The preservation of retrolental vitreous isthought by some to mitigate cataract formationpost­op. In addition, the amount of vitreous removed
determines how much balanced salt solution is infused,varying from more than 10­15 ml in extensive
vitrectomies around 5 ml for limited vitrectomies.
Future further enhanced control will determine howmuch and which parts of the vitreous body are to be
removed (46). Although survey results show thepercentage of satisfied participants ranged from 85%
to 100%, most people prefer food or nutrition
supplement for treating floaters than an operation(47).
There are many uses for pineapple and its
derived ingredients. Along with papain, bromelain is
one of the most popular proteases to use for cooking
meat. The potential medical uses of the bromelain
may be due to its proteases. However, bromelain has
not been scientifically proven to be effective intreating any diseases and has not been approved by
the
U.S. Food and Drug Administration forthetreatment of any disorder. In the US, the passage of
the Dietary Supplement Health and Education
Act allows the sale of bromelain­containing dietary
supplements, even though efficacy has not been
confirmed. However, bromelain could be used as aknown allergen. Currently, bromelain is used as a
dietary supplement for nasal swelling, inflammation,
osteoarthritis,poor
digestion,
osteoarthritis(knee), increased heart rate, adjusting menstrual
problems, cardiovascular disease, burn, wound care,pain control, antithrombotic, anti­inflammatory,
various anti­cancer effects, acute rhinosinusitis,
preventing pulmonary edema, stimulating contraction,
slowing the clotting system, improving the absorptionof antibiotics, preventing cancer, reducing labor, andassisting the body in eliminating fat, improving
antibiotic absorption, minimizing muscle sorenessafter intense exercise, relieving pain related to arthritis
and knee concern, gout, bruises, ulcerative colitis,
tendonitis, carpal tunnel syndrome and inhibiting theability of colorectal cancer [48,49,50,51,52,53,54].
Moreover, bromelain is also claimed as a tooth plaqueremoval enhancer in toothpastes. Furthermore,
systemic enzyme therapy consisting of combinationsof proteolytic enzymes such as bromelain,trypsin, chymotrypsin, and papain were alsoprescribed. However, some people may induce
allergic reactions to pineapples and we should pay
attention to the phenomena. Fortunately, there wereno special side effects or discomfort in our treatment
with pineapples.
Plant proteases play an essential role in many
regulatory processes associated with events in tissue
growth and environmental change. In addition, theproteases are important in responding to various

26

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

stresses such as wounding or the proliferative phase.
For example, the new protease “Anti­acanthin” wasisolated from the “Bromeliaceae” which may be used
to dissolve the proliferative fibrils in vitreous (55).
The cysteine protease is the most abundant inBromeliaceae, including papain, bromelain and ficin(56). In eclectic microscopy, we could easily find that
insoluble fibrils could be de­polymerized into asoluble form by several proteolytic enzymes such as
pepsin and ficin. Furthermore, the swollen fibrils
should be found after digestion by pyrolytic enzymes.
The above evidence should be used to explain why thepatients taking pineapples may decrease their vitreous
floaters. In fact, pineapples have a long tradition as a
medicinal plant among the natives of South andCentral America. Isolation of bromelain was recordedby the Venezuelan chemist Vicente Marcano in 1891
by fermenting the fruit of pineapple. In 1892, someauthors investigated the matters more completely, andcalled it 'bromelin'. Later, the term 'bromelain' wasintroduced and originally applied to any protease fromthe plant family Bromeliaceae. Bromelain from thepineapple is a mixture of protein­digesting(proteolytic) enzymes and several other substances insmaller quantities. Moreover, the proteolytic enzymes
are sulfhydryl proteases; a free sulfhydryl group of acysteineamino acidside chain is required for function.
Now several researchers all found that bromelain ispresent in parts of the pineapple plant, but the stem isthe most common commercial source, because us­able
quantities are readily extractable after the fruit has
been harvested (57, 58). According to classifications(E.C number): bromelain may be separated into 2
major
extract
components:
stem bromelain(EC 3.4.22.32) and fruit bromelain (EC 3.4.22.33).
However, stem­bromelain is distinguished fromfruit­bromelain, previously called bromelain. These 2
enzyme numbers are not the same; in other words,
various biochemistry activities should be different inusage. Pineapples are mainly grown in Thailand,
Malaysia and Taiwan. Bromelain is extracted from thepeel, stem, leaves or waste of the pineapple plant after
processing the fruit for juice or other purposes. The
starting material is blended and pressed through afilter to obtain a supernatant liquid containing thesoluble bromelain enzyme. Further processing
includes purification and concentration of the enzyme.
Vitreous may maintain the transparency for
maximal photon transmission to the retina. Besides,
vitreous may also maintain lens transparency by
mitigating the effects of reactive oxygen species onlens proteins, thus preventing cataracts. This
antioxidant effect is primarily the result of highconcentrations of ascorbate in vitreous, an observation
originally made in 1944 by Friedenwald andcolleagues. Therefore, another pathway to dissolve thevitreous opacities may be by the theory of reactive
oxygenase species (ROS) which is very popular inmany studies. For example, Yeh et al. found that ROS
levels were significantly elevated in the vitreous fluidof proliferative diabetic retinopathy (PDR) patients,
and patients with a more advanced clinical PDR
appearance had higher ROS levels. Moreover, theROS theories and oxidative stress might be correlatedwith PDR severity (59). Besides, Akiba demonstrated
that ROS may contribute to vitreous liquefaction
which is a part of the normal ocular aging process andassociated with vitreoretinal pathology. It is found thatthe hyaluronic acid, one of the main components ofvitreous gel, could be degraded by ROS, including
free radicals. It is believed that the structural changes
in vitreous may be caused by ROS (60). Upon
inflammation, the vitreous gel contracted and released
a water­like liquid. In addition, superoxide dismutase
can suppress the liquefaction; the destruction of thevitreous gel structure resulted from ROS generated byinflammatory cells. Although many unknown factors
contribute to vitreous liquefaction, ROS may be themain cause of vitreous structure alterations. Recently,
Bromelain was found to have anticancer effects; themechanisms were explored by assessing the role ininducing ROS, superoxide, autophagosomes, andlysosomes. Therefore, the abilities to lower the higher
levels of ROS in pineapple were considered as thepossible mechanisms of treating vitreous floaters by
the effectiveness of bromelain (62). Müller and his
co­workers also found that bromelain, cysteine
proteases from pineapple have the biochemical
activities to decrease oxidative stress, which may
induce the rapid progression of floaters and PVD in
vitreous cavity. As for the pathways, inhibiting
NFκB/AMPK signaling as well as their downstream
signaling proteins such as p­AKT, p­ERK, and p­Stat3
play the key role. Additionally, MMP9 and otherepithelial mesenchymal­transition markers werepartially found to be downregulated. Apoptosis was
induced after bromelain treatment (62). Hence, ourtherapeutic option might reveal new insights for thetreatment of human floaters, PVD and associatedvitreous fibrils. Our studies revealed that thepineapple supplement every day can offer a cheap
alternative to current therapies for the vitreous floaters,
which is the first report in the world.
There are several limitations in our study. Firstly,
the amount of pineapple which we used included 1, 2
or 3 pieces (each piece was approximate 120 g) whichis easily calculated but the total amount taken
deserved doubt. In the future, we may select anotherdedicated method to ensure an exact food supplement.
Secondarily, in the whole studies, the pineapples wereobtained from Kaohsiung, Tainan, and Ping­Tung
cities, and randomly separated to the different groups27

Journal of American Science 2019; 15(4)http://www.jofamericanscience.org

for various treatments. We did not further trace thedifferent extracts from the distinct geographic areas.
Besides, we did not know if the bromelain from the 3
cities and its associated hydrolytic enzymes weresimilar. Lastly, we did not further extract the moredetailed biochemistry substances and the exacthydrolytic enzymes for lysing the vitreous floaters andstrains. We will analyze the associated problems andfind true answers in the future.

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incidence of retinal breaks in the presenting andfellow eyes in patients with acutesymptomatic
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9. López­guajardo L, Pareja­estban J, Teus­guezala
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Ophthalmol 2006; 141(6): 1154­6.
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Eligibility criteria for Nd: YAG laser treatmet of
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Conclusion
To our knowledge, this is the first proven study
showing that pineapple would effectively cut andclear the vitreous opacities and the associated vitreous
strands which impact various physiological andpsychological effects of eyes.
Furthermore, this study found that pineapple
may significantly dissolve and remove vitreous
floaters. For the patients with acute–onset floaters andeven flashes, it sometimes led to severe VMT,
macular holes and even RD which would induce
blindness. In the experiments of our survey, we foundthat pharmacyte vitreolysis from the regular intake ofpineapple could decrease the rate of the vitreous
floaters with less complication. Moreover, we believethat pineapple supplement is suitable for patients
presenting floaters and the associated vitreous
problems. Besides, we will further find the exact
biochemical properties and real pathway in dissolving
vitreous floaters.
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