bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual Function Before and After Photorefractive Keratectomy for Myopia
Authors: Ambrosio Gennaro , Cennamo Giovanni , De Marco Rocco , Loffredo Luciano , Rosa Nicola , Sebastiani Adolfo
Published: April 2021

ABSTRACT

BACKGROUND: To date, Snellen visual acuity and postoperative refraction have been used to evaluate the results of photorefractive keratectomy. However, other parameters, such as contrast sensitivity function and glare, may be affected by refractive surgery and lead to unsatisfactory visual performance. This prospective study is aimed at evaluating the effect of photorefractive keratectomy on contrast sensitivity function and glare.

SUBJECTS AND METHODS: Static contrast sensitivity function, dynamic contrast sensitivity function, and glare sensitivity were evaluated in 22 myopic eyes before as well as 1, 3, and 6 months after photorefractive keratectomy. The eyes tested were divided into three groups, according to the amount of myopia: group I, from - 4.00 to - 8.00 diopters (D); group II, from -8.25 to -11.00 D; group ??, from -11.25 to -20.00 D.

RESULTS: Both static and dynamic contrast sensitivity function at the intermediate spatial frequencies were altered at 1 month after photorefractive keratectomy, with a trend toward recovery at 3 and 6 months postoperatively. Glare sensitivity was not significantly affected by surgery.

CONCLUSIONS: Contrast sensitivity function and glare testing may show abnormalities in the presence of optimal visual and refractive results. These tests may result especially important for the evaluation of new refractive surgical procedures. [J Refract Corneal Surg. 1994;10:129-136.]
Photorefractive Keratectomy Following Penetrating Keratoplasty
Authors: John Maurice E , Martines Eduardo , Cvintal Tadeu , Filho Agenor Mellor , Soter Frederico , de Sousa Maria Cristina Barbosa , Boleyn Karen L , Ballew Carol
Published: April 2021

ABSTRACT

We present 3 eyes that underwent photorefractive keratectomy (PRK) for residual myopia after penetrating keratoplasty, and 1 eye that was treated for recurrent granular dystrophy and myopia following penetrating keratoplasty. The 3 refractive eyes experienced improvements in visual acuity and refractive error through 3 months postoperative, but exhibited regression of effect after 6 months postoperative. One eye also exhibited substantial corneal haze at three months postoperative that was not responsive to steroid retreatment. The eye with granular dystrophy obtained symptomatic relief as well as improvement in vision.

We tentatively conclude that the corneal transplant reacts to photorefractive keratectomy in much the same way as a normal cornea. Eyes with substantial degrees of post-graft myopia exhibit regression of refractive effect, much like high myopes following primary photorefractive keratectomy. Photorefractive was unable to prevent the recurrence of granular dystrophy in the transplanted tissue. The eyes reported here achieved only modest long-term visual and refractive improvements. [J Refract Corneal Surg. 1994:10:S206S210.]
Transverse Keratotomy Combined with Spherical Photorefractive Keratectomy for Compound Myopic Astigmatism
Authors: Ring C Peter , Hadden O Bruce , Morris Antony T
Published: April 2021

ABSTRACT

This is a report of a study of 40 eyes in which transverse keratotomy was performed in conjunction with spherical photorefractive keratectomy. The preoperative range of myopia was -1.50 to -13.50 diopters (D). The mean attempted cylindrical correction was -1.73 D (range -0.75 to -4.00). After 6 months 47.8% achieved unaided visual acuity of 6/6, 60% achieved 6/9 or better and 75% achieved 6/12 or better. The mean postoperative spherical equivalent refraction was -0.01 D at 6 months. The mean astigmatism postoperatively was 0.32 D. A group of 179 eyes with six months follow-up after photorefractive keratectomy who had not had transverse keratotomy was compared. Their mean postoperative spherical equivalent refraction was -0.07 D and mean astigmatism was 0.21 D. Uncorrected visual acuity was 6/12 or better in 93.3%. Until there is an improvement in the mechanism of the ablatable mask this combined procedure offers patients with significant astigmatism the opportunity of achieving good visual results. [J Refract Corneal Surg. 1994;10:S217-S221.1
Photorefractive Keratectomy for Myopia in 98 Eyes
Authors: Murta Joaquim Nato , Proenca Rui , Van Velze R A , Trassos Antonio
Published: April 2021

ABSTRACT

Photorefractive keratectomy (PRK) was performed on 98 consecutive normal myopic eyes with the Summit OmniMed laser System. The minimum follow-up was 3 months and 31 were followed for 6 months. Preoperative myopia ranged from -1.25 to -12.00 D.

The myopic eyes were divided into 4 groups according to the amount of myopia: group 1 (-1.25 to -3.00 D), 17 eyes; group 2 (-3.12 to -6.00 D), 42 eyes; group 3 (-6.12 to -9.00 D), 29 eyes and group 4 (>9.00 D), 10 eyes.

In group 1 mean uncorrected visual acuity was 0.87 at 3 months, 1.0 at 6 months and all of the eyes were within 0.50 D of the attempted correction.

In group 2 mean uncorrected visual acuity was 0.76 at 3 months, 0.87 at 6 months and 92.3% of the eyes were within 0.50 D of the attempted correction.

In group 3 mean uncorrected visual acuity was 0.65 and 0.66 at 3 and 6 months respectively and 77.8% of eyes were within 0.50 D of the attempted refractive correction.

In group 4, mean uncorrected visual acuity was 0.46 and 0.7 at 3 and 6 months, respectively, and 100% were within 0.50 D of the attempted correction.

Two eyes lost 2 lines and 4 eyes gained 2 or more lines of their preoperative best spectacle corrected visual acuity. Three eyes exhibited steroid induced rise in intraocular pressure that was controlled with topical timolol. No serious complications occurred.

Despite the short follow-up, photorefractive keratectomy with the 193 nm excimer laser appears to be an effective and safe treatment for the correction of myopia. [J Refract Corneal Surg. 1994;10:S231S235.1
Treatment of Myopic Astigmatism With Photorefractive Keratectomy Using an Erodible Mask
Authors: Cherry Paul M H , Tutton Miles K , Bell Andrew , Neave Christopher , Fichte Claus
Published: April 2021

ABSTRACT

The Summit Technology erodible mask treatment of astigmatism does not alter the keratometric astigmatism significantly, even though the refractive astigmatism appears to improve by about 50%.

Myopia is satisfactorily treated with the erodible mask, but there is slightly more undercorrection compared to photorefractive keratectomy (PRK) using an expanding diaphragm. Increasing the minus power in ordering the mask cylinder improves the myopia result, but not the keratometric astigmatism result.

The following factors do not influence the keratometric astigmatism result: 1) The type of astigmatism (with-, against-the-rule, or oblique); 2) The initial keratometry readings; and 3) The time from the commencement of epithelial removal to laser treatment. [J Refract Corneal Surg. 1994;10:S239S245.1
A Simplified Method to Perform Photorefractive Keratectomy Using an Erodible Mask
Authors: Gobbi Pier Giorgio , Carones Francesco , Scagliotti Franco , Venturi Elisabetta , Brancato Rosario
Published: April 2021

ABSTRACT

BACKGROUND: Photorefractive keratectomy (PRK) using the current erodible mask technique is difficult to perform, because of the stringent requirements in the alignment of the eye to the mask and in the centration of the mask under the laser beam. The surgeon has to manually control the eye-cup over 5 degrees of freedom. If not accurately done this may lead to decentration of the ablation and bring about technical problems during treatment. The aim of this study was to find a way to improve and simplify the erodible mask procedure.

METHOD: We used a modified non-contact mask eye-cup with a rigid mechanical support to obtain a precise and reliable positioning in space of the mask itself. Eye centration over the pupillary aperture was obtained with conventional patient fixation on the reference aiming light, coaxial to the laser beam path, and controlled using two He-Ne beams aimed at the corneal apex.

RESULTS: Good reliability was demonstrated in the first 22 eyes operated on using this technique. All the masks were ablated with good centration of the laser beam over the polymethylmethacrylate (PMMA) button, and all the treatments were satisfactorily centered over the pupillary aperture. No complications or side effects were encountered during the treatments.

CONCLUSIONS: Compared to the conventional erodible mask procedure, this technique proved much faster to perform, was more comfortable for both patient and surgeon, and was technically easier for the operator. [J Refract Corneal Surg. 1994;10:S246-S249.]
Correction of Myopia and Astigmatism Using an Ablatable Mask
Authors: Hersh Peter S , Patel Rachna
Published: April 2021

ABSTRACT

BACKGROUND: Most excimer laser refractive procedures use a computer driven mechanical diaphragm to shape the laser beam. Studies are currently underway using an ablatable polymethylmethacrylate (PMMA) mask to transfer a new spherical or toric curve to the cornea for the correction of myopia and astigmatism; it may leave a smoother corneal surface than diaphragm procedures.

METHODS: As part of a Phase Hb FDA clinical study, 25 eyes of 25 patients underwent excimer laser photorefractive keratectomy using a hand held ablatable mask. Fifteen eyes had attempted spherical corrections of up to 6.00 diopters (D) and 10 had toric corrections of up to 6.00 D of sphere and 2.75 D of astigmatism.

RESULTS: Seventy-four percent of all eyes achieved uncorrected visual acuity of 20/40 or better - 86% in the spherical group and 63% in the astigmatism group. Sixty-nine percent of eyes were within +/- 1 D of the attempted correction. In eyes treated for astigmatism, mean astigmatism decreased from 1.48 D preoperatively to 0.86 D postoperatively. Approximately one half of the eyes treated for astigmatism had a decrease in cylinder of more than 0.5 D. One eye lost 2 Snellen lines of best spherical corrected visual acuity. Video keratography showed toric ablations to result in an elliptical optical zone. Analysis of centration of the procedure showed 66% of ablations centered within 1.0 mm of the center of the pupil aperture.

CONCLUSIONS: The ablatable mask represents a promising modality for the treatment of eyes with both myopia and myopic astigmatism. [J Refract Corneal Surg. 1994;10:S250-S254.J
Keratomileusis-In-Situ Using Manual Dissection of Corneal Flap for High Myopia
Authors: Gomes Marcos
Published: April 2021

ABSTRACT

Overcorrection, regression and haze are some side-effects found after excimer laser photorefractive keratectomy (PRK) for high myopia. A new method attempts to avoid photoablation through Bowman's layer, using the stroma to flatten the cornea without use of a microkeratome. Manual surgical instruments such as the diamond blade, spatula, Pierce forceps, and Vannas scissors are used to remove a disc of anterior cornea. Minimal topical corticosteroids are used, avoiding the complications of prolonged corticotherapy.

Six eyes underwent manual excimer laser keratomileusis-in-situ. Postoperatively, the epitheliums in these eyes initially were dry and excoriated. By the twentieth day, however, the eyes had re-epithelialized and recovered. The optical effect is the same as when keratomileusis is used. No more than threefourths of the pre-existing myopia was used in the program as some undercorrection was desired. [J Refract Corneal Surg. 1994;10:S255-S257.]
Holmium: YAG Laser Thermokeratoplasty for Hyperopia
Authors: Durrie Daniel S , Schumer D James , Cavanaugh Timothy B
Published: April 2021

ABSTRACT

HolmiumrYAG laser thermokeratoplasty (LTK), a procedure using a solid-state infrared laser to treat hyperopia, was performed on 10 patients in phase I and 16 patients in phase II - in a total of 29 eyes at the Hunkeler Eye Clinic. Phase II was redesigned after phase I results showed undercorrection and regression. The follow-up period ranged from 1 to 24 months (mean 10.9 months). A total of 79% of phase II patients were within +/- 1.00 D of intended correction at the 6-month visit. Looking at both phases together, no patients had J2 or better near vision preoperati vely, but 75% had J2 or better at the 6-month visit. A total of 43% of eyes in phase II lost 1 line and 7% lost two lines of best spectacle corrected visual acuity due to induction of irregular astigmatism. The surgical challenges are to insure appropriate centration of the procedure about the optical axis. Concerns about regression and stability will be defined as these patients are followed through their 2-year visits. [J Refract Corneal Surg. 1994;10:S277S280.1
Photorefractive Keratectomy for the Treatment of Myopia After Epikeratoplasty: A Case Report
Authors: Loewenstein Anat , Lipshitz Isaac , Lazar Moshe
Published: April 2021

ABSTRACT

An aphakic eye with a +9.00 diopter (D) refraction developed high myopia of -13.00 D after applying epikeratoplasty using a + 14.00 D lenticule. We preformed photorefractive keratectomy by excimer laser. The procedure was uneventful, with no postoperative pain. Epithelialization occurred as usual. Recovery of the cornea followed the usual course with initial overcorrection followed by certain regression. After 7 months follow-up the spherical equivalent was -3.25 D and the lenticule was clear.

In myopia after epikeratoplasty photorefractive keratectomy is an effective alternative to lenticule exchange. [J Refract Corneal Surg. 1994; 10:S285S286.]
Myopic Keratomileusis by Excimer Laser on a Lathe
Authors: Ganem Stéphane , Aron-Rosa Daniele , Gross Michel , Rosolen Serge
Published: April 2021

ABSTRACT

BACKGROUND: We designed an excimer laser keratomileusis delivery system to increase the regularity of the refractive cut surface and allow greater precision in the level and shape of the ablated zone.

METHODS: A parallel faced corneal disc was produced by microkeratectomy from six human eyes and surgical keratectomy in 12 beagle corneas. A 193-nanometer excimer laser that was used to project an oval beam onto the corneal disc was rotated on a flat surface to ensure overlapping of the ovally ablated areas between pulses.

RESULTS: Electron microscopy of eye bank lenticules demonstrated a circular smooth regularly concave ablation zone. Histological examination of nine clear corneas confirmed thinning of the stroma without fibroblastic reaction and no epithelial hypertrophy. Mean preoperative corneal power of 43.15 ± 2.18 decreased postoperatively to 33.61 ±2.34.

CONCLUSIONS: The new technique of excimer laser keratomileusis has the advantage of a cut surface smoother and the clear zone is devoid of the stepwise concavity and irregularity seen in diaphragm based photoablation delivery systems. [J Refract Corneal Surg. 1994;10:575-581.]
Simple Method of Transscleral Fixation of a Posterior Chamber Intraocular Lens in the Absence of the Lens Capsule
Authors: Kershner Robert M
Published: April 2021

ABSTRACT

BACKGROUND: There are several advantages to implanting a posterior chamber intraocular lens (IOL) in the ciliary sulcus when the lens capsule is absent.

I have developed a simple method of fixating an IOL into the ciliary sulcus which does not require different needles, multiple needle passes, scleral dissection, or awkward surgical maneuvers.

METHODS: Thirty eyes were enrolled in this study. All eyes were either aphakic, requiring a secondary lens implantation, or required IOL exchange. The patients were followed for 30 months.

Using a single 10-0 double-armed, polypropylene suture, a through-and-through infracuiary scleral pass secured each haptic without tying. The lens was then positioned into the ciliary sulcus and the knots tied outside the eye under direct visualization.

RESULTS: This procedure has been used in 30 eyes without erosion of sutures, dislocation or tilting of the IOL, or induced astigmatism. Twenty-one eyes (70%) had spectacle-corrected visual acuity of 20/40 or better.

CONCLUSION: The results of this study demonstrate that posterior chamber transscleral fixated IOLs give improved postoperative visual results. [J Refract Corneal Surg. 1994;10:647-651.]
Laser in Situ Keratomileusis for Myopia and Hyperopia Using the Lasersight 200 Laser in 300 Consecutive Eyes
Authors: Reviglio Victor E , Bossana Erica L , Luna José D , Muiño Juan C , Juarez Claudio P
Published: April 2021

ABSTRACT

PURPOSE: To evaluate effectiveness, safety, predictability, and short-term stability of laser in situ keratomileusis (LASIK) using the LaserSight Compac-200 Mini excimer laser with software version 9.0, for all refractive errors.

METHODS: One hundred fifty consecutive patients (300 eyes) that received bilateral LASIK for myopia, hyperopia, and astigmatism were studied prospectively. A new 9.0 software version applying a modified nomogram that takes advantage of bilateral surgery was used. Follow-up at 6 months was available for 267 eyes (89%).

RESULTS: Six months postoperatively, 131 eyes (96.32%) in the low to moderate myopia group (-1.00 to -5.99 D; n=136) had a spherical equivalent refraction within ±1.00 D, and 123 eyes (90.44%) were within ±0.50 D of emmetropia. In the high to extreme myopia group (-6.00 to -25.00 D; n=114), 97 eyes (87.08%) had a spherical equivalent refraction within ±1.00 D and 78 eyes (68.42%) were within ±0.50 D of emmetropia. In the hyperopia group (+1.00 to +6.00 D; n=50), 44 eyes (88%) had a postoperative spherical equivalent refraction within ±1.00 D, and 31 eyes (62%) were within ±0.50 D of emmetropia. Mean change in spherical equivalent refraction at 6 months was less than -0.50 D in the low to high myopia groups and -1.16 ± 0.55 D in the extreme myopia group. At 6 months follow-up, uncorrected visual acuity was 20/20 or better in 73 eyes (54%) in the low to moderate myopia groups and 21 eyes (18%) in the high to extreme myopia groups. In the hyperopia group at 6 months followup, uncorrected visual acuity was 20/20 or better in 31 eyes (62%) and 20/40 or better in 41 eyes (82%). Only two eyes had a temporary loss of two or more lines of spectacle-corrected visual acuity due to corneal folds that were surgically treated. Six months after LASIK, no eye had lost any lines of best spectacle-corrected visual acuity in this series.

CONCLUSIONS: Our modified LASIK nomogram with the 9.0 software of the LaserSight 200 excimer laser (with a larger and smoother ablation pattern) resulted in safe and effective outcomes for the treatment of low to high myopia, astigmatism, and hyperopia. [J Refract Surg 2000;16:716-723]
Early Rhegmatogenous Retinal Detachment Following Laser in situ Keratomileusis for High Myopia
Authors: Farah Michel Eid , Höfling-Lima Ana Luisa , Nascimento Ednei
Published: April 2021

ABSTRACT

PURPOSE: Four eyes had early rhegmatogenous retinal detachment within 3 months of laser in situ keratomileusis (LASIK) for correction of high myopia using the microkeratome, Clear Corneal Molder.

METHODS: In two eyes, retinal detachment resulted from horseshoe tears, one occurring in an otherwise normal region of the retina and the other at the margin of an area of lattice degeneration detected during preoperative examination. The first eye was treated with retinopexy using a 287 encircling scleral exoplant, drainage of eubretinal fluid, and laser photocoagulation by indirect ophthalmoscopy. The other eye was treated with pneumatic retinopexy and cryotherapy. In the other eyes, retinal detachment was the result of giant tears with no evidence of prior retinal degeneration. These eyes were treated with pars plana vitrectomy, fluid-gas exchange with 15% perfluoropropane (C3F8), endolaser photocoagulation, and a 42 encircling scleral exoplant.

RESULTS: After treatment, the first two eyes achieved spectacle-corrected visual acuity of 20/40. In the last two eyes, final spectacle-corrected visual acuity was 20/400 in one eye and light perception in the other.

CONCLUSIONS: Although no cause-effect relationship between LASIK and retinal detachment can be stated, these cases suggest that LASIK may be associated with retinal detachment, particularly in highly myopic eyes. Further studies are necessary to determine high-risk patient characteristics. [J Refract Surg 2000;16:739-743]
Fellow Eye as a Predictor for Keratoconus Progression Following Accelerated Corneal Cross-linking
Authors: Mimouni Michael , Sorkin Nir , Hatch Wendy , Slomovic Allan R. ,   KEI CXL Study Group, Singal Neera
Published: April 2021

PURPOSE:

To assess the fellow eye as a predictor for keratoconus progression following bilateral same-day accelerated corneal cross-linking (A-CXL).

METHODS:

This was a post-hoc analysis of data from a prospective study of bilateral A-CXL for progressive keratoconus between 2013 and 2015. The primary outcome measures were absolute change in maximum keratometry (Kmax) (diopters [D]), relative change in Kmax (%), and A-CXL progression (increase in Kmax > 2.00 D). Responses in both eyes were measured by the change in Kmax, with the right eye serving as the “predictor” of progression for the left eye.

RESULTS:

Three-hundred ninety-two eyes (196 patients) with a mean age of 26.8 ± 7.7 years were included. There was a significant correlation in absolute and relative Kmax change (
r
= 0.26,
P
< .001 and
r
= 0.32,
P
< .001, respectively) between right and left eyes. In regression analysis, the only significant predictors of change in Kmax in the left eye were preoperative Kmax of the left eye (
P
< .02) and change in Kmax of the right eye (
P
< .001). Eyes that progressed in the right eye were more likely to progress in the left eye (29.4% versus 4.5%, odds ratio = 8.85,
P
< .001). In multiple regression, right eye progression of greater than 2.00 D was the significant predictor of left eye progression of greater than 2.00 D (odds ratio = 15.15,
P
< .007).

CONCLUSIONS:

This large-scale study of keratoconus following A-CXL indicates that patients with progression in the right eye were 15.5 times more likely to have progression in the left eye. Patients with progression following A-CXL in one eye should be closely observed due to increased risk of progression in the fellow eye.

[
J Refract Surg
. 2021;37(3):186–191.]
Corneal Tomographic Analysis Among Patients With Thyroid Gland Dysfunction
Authors: Bassiouny Rania M. , Awad Eman A. , Gaafar Walid , Kyrillos Fady A. , Abou Samra Waleed A. , Abdelhameed Ameera G.
Published: April 2021

PURPOSE:

To analyze the corneal tomographic parameters of patients with thyroid gland dysfunction.

METHODS:

This case–control study included 100 eyes of 50 patients with thyroid gland dysfunction and 100 eyes of 50 healthy controls. All eyes were examined by Pentacam (Oculus Optikgeräte GmbH). Pentacam parameters were compared between patients with thyroid gland dysfunction and controls. Spearman's correlation coefficient between different Pentacam parameters and the serum level of free thyroxin (T4) and thyroid-stimulating hormone (TSH) was calculated.

RESULTS:

Patients with hypothyroidism had significantly higher median values of steep and maximum simulated keratometric readings, central corneal thickness (CCT), and thinnest pachymetry (CTmin) than both patients with hyperthyroidism and controls (
P
⩽ .05). The median values of the average and maximum pachymetric progression index (PPI), posterior elevation, and back difference elevation were significantly higher in patients with hyperthyroidism than in patients with hypothyroidism and controls (
P
⩽ .05). The Ambrósio Relational Thickness (ARTmax) was significantly reduced in patients with hyperthyroidism (
P
⩽ .001). Both CCT and CTmin showed a moderately positive correlation with serum TSH level and a moderately negative correlation with serum free T4 level. Patients with non-autoimmune thyroid gland dysfunction had significantly thinner CCT, CTmin, and inferior vertical deviation than the autoimmune group (
P
⩽ .05).

CONCLUSIONS:

Thyroid gland dysfunction is associated with significant corneal tomographic changes. Patients with hyperthyroidism tend to have thinner corneas and more abnormal tomographic parameters correlating with keratoconus. No significant tomographic changes were found in association with autoimmune thyroid gland dysfunction. The authors recommend screening and regular follow-up of patients with thyroid gland dysfunction for early detection and management of keratoconus.

[
J Refract Surg
. 2021;37(3):192–197.]
Targeted Lens Pitting to Treat Negative Dysphotopsia
Authors: Feng Yilin , Weinlander Eric , Shah Manjool
Published: April 2021

PURPOSE:

To describe a patient with negative dysphotopsia who underwent a novel non-invasive technique that uses the Nd:YAG laser to induce nasal light scattering through targeted lens pitting.

METHODS:

Case report.

RESULTS:

Symptoms of negative dysphotopsia resolved after targeted lens pitting.

CONCLUSIONS:

Targeted lens pitting with Nd:YAG laser is a potential technique that may help treat negative dysphotopsia in a manner that preserves intraocular anatomy. Further study is warranted to explore targeted lens pitting in both patients with and without prior retinal surgery as a treatment for negative dysphotopsia.

[
J Refract Surg
. 2021;37(3):212–214.]
Visualization of Berger's Space in the Living Eye
Authors: Weidle Egon G
Published: April 2021

ABSTRACT

The presence of the capsulo-hyaloidal interspace (Berger's space) can be demonstrated in the living human eye when this space is filled with Healon during extracapsular lens surgery combined with primary capsulotomy. This facilitates discission and excision procedures of the posterior capsule and protects the anterior vitreous face from injury.
Proliferative Sickle Retinopathy and Neovascularization of the Disc: Regression Following Treatment With Peripheral Retinal Scatter Laser Photocoagulation
Authors: Kimmel Andrew S , Magargal Larry E , Tasman William S
Published: April 2021

ABSTRACT

Proliferative sickle retinopathy (PSR) is usually described as a peripheral neovascular tuft in a "sea fan" like configuration. While neovascularization of the disc (NVD) is a common finding in proliferative diabetic retinopathy (PDR), to our knowledge only one other case has been reported of NVD in an S-C patient in the absence of other contributing conditions. PSR has been shown to regress after treating hypoxic peripheral retina with peripheral circumferential retinal scatter photocoagulation (PCRSP). The following is a case report of an S-C patient with PSR and NVD/ NVR which was originally treated elsewhere with scatter argon laser photocoagulation from the vascular arcades to just behind the equator. The peripheral "sea fan" and NVD did not regress. PCRSP to the zone of peripheral ischemia was then performed, and regression of the NVD and peripheral "sea fan" was achieved. This case illustrates the importance of concentrating laser treatment to the zones of retinal ischemia to achieve regression of associated neovascularization.
Purulent Anterior Segment Endophthalmitis Following Paracentesis
Authors: Joondeph Brian C , Joondeph Howard C
Published: April 2021

ABSTRACT

A 67-year-old man developed a central retinal artery occlusion and was treated with an oral carbonic anhydrase inhibitor, oral glycerin, carbachol rebreathing, and anterior chamber paracentesis. He subsequently developed an anterior segment endophthalmitis. Vigorous medical and surgical management cured the endophthalmitis, but his visual acuity remained at light perception.

To the best of our knowledge, this patient represents the first reported case of a culture-positive, anterior segment endophthalmitis following anterior chamber paracentesis.
Transscleral Cyclophotocoagulation Using a Neodymium YAG Laser
Authors: Fankhauser Franz , van der Zypen Eugen , Kwasniewska Sylvia , Rol Pascal , England Cheri
Published: April 2021

ABSTRACT

The effects of a neodymium:YAG laser, working in the free-running mode (1 and 20 millisecond pulses), upon the ciliary body via the transscleral route have been studied using 16 autopsy eyes. The experiments described were designed to find an efficient strategy of transsciera] cyclodestruction of the ciliary body. It was found that pulse energies of between 6 and 7 Joules, an exposure duration of 20 milliseconds, and maximal defocusing are optimal. A beam, tangentially oriented and positioned 1/2 to 1 mm posterior to the limbus has a high probability of hitting the ciliary body and damaging the ciliary processes. In these experiments a first generation of contact lenses could not be demonstrated to have an advantageous effect.
Orbital Volume Augmentation With Adjustable Prefabricated Methylmethacrylate Subperiosteal Implants
Authors: Dresner Steven C , Codère Francois , Corriveau Christine
Published: April 2021

ABSTRACT

Prefabricated right and left subperiosteal implants were used in nine anophthalmic sockets to correct superior sulcus deformities. The advantages of these implants include increased stability, easy insertion under direct visualization and the possibility of easy retrieval if necessary, and custom modification for volume and shape intraoperatively, with the addition of methylmethacrylate. There were no extrusions, implant migrations, or infections. Complications included mild undercorrection, upper eyelid blepharoptosis, and transient ectropion.
Surgical Treatment for a Case of Postoperative Pseudallescheria boydii Endophthalmitis
Authors: Bouchard Charles S , Chacko Benjamin , Cupples Howard P , Cavanagh H Dwight , Mathers William D
Published: April 2021

ABSTRACT

Pseudallescheria boydii (P. boydii) is an uncommon ocular pathogen which previously has been identified in only 10 of 905 fungal isolates identified by the Sid Richardson Microbiology Laboratory at the Cullen Eye Institute of Baylor College of Medicine. Furthermore, only one case of postoperative P. boydii endophthalmitis1 and four cases of endogenous P. boydii endophthalmitis have been reported.2-5 Three of the four patients with endogenous endophthalmitis died within 4 weeks of diagnosis. We describe a second case of postoperative endophthalmitis due to this fungus. The infection was successfully eradicated following vitrectomy, corneoscleral resection, and patch graft, in addition to intraocular, topical, and oral antifungal medication. Although in vitro sensitivities are variable, P. boydii is known to be relatively resistant to amphotericin B. This points to the importance of proper cultures and sensitivities when treating cases of suspected fungal endophthalmitis. Unfortunately, the patient's eye became phthisical 6 months following the initial intervention.
Intraocular Lens Damage in Experimental Nd:YAG Laser Capsulotomy: A Comparison of Perspex CQ and Cross-Linked PMMA Lenses
Authors: Erbil Hasan , Sinav Satvet
Published: April 2021

ABSTRACT

The threshold resistance to Nd:YAG laser irradiation of cross-linked lathe-cut PMMA intraocular lenses was slightly higher than that of Perspex CQ lenses: 6.0 mJ vs 4.5 mJ for single laser spots, and 3.5 mJ vs 3.0 mJ for four spots. These levels produced nicks and pits in the lenses; higher levels created small breaks.
Transscleral Cyclophotocoagulation Using a Semiconductor Diode Laser in Cadaver Eyes
Authors: Hennis Hugh L , Assia Ehud , Stewart William C , Legler Ulrich F C , Apple David J
Published: April 2021

ABSTRACT

We studied the effectiveness of semiconductor diode laser transscleral cyclophotocoagulation in cadaver eyes using the Miyake technique and light microscopy.

Thermal lesions in the ciliary processes were induced with 0.7-second, 1200-mW, and 100- to 500-µ applications, 0.5 mm from the surgical limbus and defocused 1 mm posteriorly. An effective ciliary body reaction was observed grossly as tissue blanching, shrinkage, and pigment dispersion; and histologically, as coagulation necrosis and epithelial cell disruption. No damage to crystalline or intraocular lenses was evident.

This successful application of diode laser transscleral cyclophotocoagulation in cadaver eyes suggests that it may prove useful in treating patients with glaucoma.
Response of Argon Laser Trabeculoplasty With Varying Anterior Chamber Anatomy
Authors: Pennebaker Gordon E , Stewart William C
Published: April 2021

ABSTRACT

We studied one randomly selected eye of 50 consecutive primary open-angle glaucoma patients treated with argon laser trabeculoplasty to assess response differences as functions of anterior chamber anatomy and refraction. We found no significant differences related to these variables, and thus conclude that argon laser trabeculoplasty may be performed successfully in patients with crowded angles as long as the trabecular meshwork can be visualized.
Epithelial Downgrowth Following the Removal of Iris Inclusion Cysts
Authors: Orlin Stephen E , Raber Irving M , Laibson Peter R , Shields Carol L , Brucker Alexander J
Published: April 2021

ABSTRACT

We present three patients in whom epithelial downgrowth occurred following the excision of iris inclusion cysts. The sheet-like downgrowth was aggressively treated and successfully eradicated in two of the three patients. Early identification and prompt therapy are essential.
The Effects of Glaucoma Medications on Tenon's Capsule and Conjunctiva in the Rabbit
Authors: Smith David L , Skuta Gregory L , Kincaid Marilyn C , Rabbani Roya , Cruess David F , Kao Sue F
Published: April 2021

ABSTRACT

Glaucoma filtering surgery fails most frequently due to fibrosis at the episcleral-conjunctival/Tenon's capsule interface. Sherwood et al have suggested that chronic topical antiglaucoma medications increase conjunctival inflammatory cells, which could increase the likelihood of fibrosis and subsequent bleb failure.1 In a pilot study in a rabbit model, we placed timolol, pilocarpine, and epinephrine, or a combination of all three, in one eye of 24 animals twice daily for 7 months. The fellow eye received distilled water. Microscopic examination revealed no statistically significant change in the number of acute or chronic inflammatory cells, fibroblasts, or goblet cells in the treated as compared with the control eyes. A longer duration of drug administration, or drug administration followed by surgical intervention, may be required to produce an effect on the conjunctiva and Tenon's capsule, if such an effect exists.
A Disposable 8-mm "Corneal Cap" to Reduce Surgical Light Exposure
Authors: Olander Kenneth W
Published: April 2021

ABSTRACT

I have devised an easily-fashioned disposable "corneal cap" that reduces light exposure to the retina from the operating microscope. The 8-mm plastic cap is the cut end of the test chamber included in all packages of disposable handpieces and tubing for automated irrigation and aspiration instruments.
"Equator Ring" for Maintenance of the Completely Circular Contour of the Capsular Bag Equator After Cataract Removal
Authors: Hara Tsutomu , Hara Takako , Yamada Yoshiharu
Published: April 2021

ABSTRACT

We designed an "equator ring," a flexible silicone rod with a groove on its inner surface, to maintain the circular contour of the capsular bag equator after cataract removal. After cataract extraction, the ring is inserted in the bag through a 5.0-mm circular capsulorhexis or 4.5-mm linear "dumbbell" opening. Then a conventional posterior chamber intraocular lens (PC-IOL) is inserted, with the IOL loops in the groove. The ring not only allows complete maintenance of the circular contour of the capsular bag equator for most conventional PC-IOLs, but also may prevent invasion of metamorphosed lens epithelial cells into the posterior capsule.
Corneal Topography as a Predictor of Refractive Change in the Prospective Evaluation of Radial Keratotomy (PERK) Study
Authors: Rowsey J James , Waring George O , Monlux Roy D , Balyeat Hal D , Stevens Scott X , Culbertson William , Barron Bruce , Nelson Daniel , Asbell Penny , Smith Ron , Arentsen Juan , Cowden John , Lynn Michael J
Published: April 2021

ABSTRACT

The first operated eyes of 435 patients undergoing radial keratotomy in the Prospective Evaluation of Radial Keratotomy (PERK) study were evaluated by photokeratography to document the preoperative and postoperative corneal shape. We determined by regression analysis and analysis of variance that the corneal shape preoperatively improved the prediction of the corneal shape 6 months postoperatively in the 3-mm-clear-zone population.

The reduction of myopia in all 435 eyes ranged from 1.25 to 9.75 diopters. We studied the effect of the preoperative corneal shape on this variability in the outcome of the surgery using rings 2 and 7 on photokeratography and corneal diameter. In the 3-mm-clear-zone group, eyes with flat prolate corneas had a greater reduction in myopia (4.65 D); those with steeper, more spherical corneas had less reduction in myopia (3.48 D). In addition, eyes with a 3-mm clear zone and flat central corneas alone (8.0 mm = 42.19 D) flattened approximately 0.75 D more than those with steep central corneas (7.0 mm = 48.21 D). In the 3.5-mm and 4.0-mm clear zone groups, the change in corneal curvature was not related to the preoperative curvature.

A stepwise regression analysis of the 151 eyes in the 3.0-mm-clear-zone population demonstrated the following predictive equation for radial keratotomy: change in cycloplegic refraction = -14.55 + [-2.097 × average ring-2 radius] + [3.605 × average ring-7 radius] + [0.69 × horizontal corneal diameter] + [0.079 × age] + [-0.379 × spherical equivalent cycloplegic refraction]. There was a 1.17-D observed difference in the effect of radial keratotomy between those eyes with a steep/steep corneal topography (7.2% of the 3.0-mm-clear-zone population) and the flat/flat topography (29% of the 3.0-mm-clear-zone PERK population). A knowledge of corneal topography provides an additional tool for understanding the operative variability of radial keratotomy.
Extracapsular Cataract Extraction and Posterior Chamber Lens Implantation in Controlled Open-Angle Glaucoma
Authors: Onali Tuula , Raitta Christina
Published: April 2021

ABSTRACT

A consecutive series of 103 eyes, 37 with controlled simple glaucoma (SG) and 66 with capsular glaucoma (CG), underwent extracapsular cataract extraction (ECCE) and posterior chamber lens (PC-IOL) implantation.

Two to 6 weeks after surgery, 48% of the SG eyes and 62% of the CG eyes had visual acuities better than 0.4, as compared with 8% and 3%, respectively, preoperatively. The corresponding figures after 12 to 43 months in the SG eyes were 62%, and after 14 to 38 months in the CG eyes, 55%.

A slight increase of mean intraocular pressure (IOP), from 19.0 ± 4.8 mm Hg to 25.3 ± 13.3 mm Hg in the SG eyes, and from 19.0 ± 3.9 mm Hg to 24.5 ± 9.6 mm Hg in the CG eyes occurred 1 to 2 weeks after surgery; at 2 to 6 weeks the mean IOPs had returned to preoperative levels: 18.1 ± 6.4 mm Hg in the SG eyes and 18.4 ± 5.9 mm Hg in the CG eyes. After a mean of 26.5 months (range, 12 to 43 months), IOP had decreased to 17.3 ± 2.9 mm Hg in the SG eyes; and after 24.2 months (range, 14 to 38 months) to 17.6 ± 5.7 mm Hg in the CG eyes.

The need for glaucoma medication was diminished at 2 to 6 weeks after surgery: IOP was controlled (<21 mm Hg) without glaucoma medication in 43% of the SG, and in 50% of the CG eyes (preoperatively, all of the SG and 89% of the CG eyes required medication). At this point IOP was controlled in 37% of the SG and in 45% of the CG eyes with only topical medications (preoperatively, more than 80% of patients in both groups required such medication). After 1 to 3 years, IOP was controlled in 19% of the SG and in 37% of the CG eyes without medication, while it was controlled in 66% of the SG and 55% of the CG eyes with only topical medications.

Surgical complications included: vitreous loss in 5% of the CG eyes, and fibrinous effusion in 8% of the SG and in 6% of the CG eyes. Early IOP rise ≥30 mm Hg occurred in 35% of the SG eyes at a mean of 1.8 days and in 27% of the CG eyes at a mean of 1.5 days postoperatively. The difference between the SG and the CG eyes in this respect was not significant.
The Effect of Retrobulbar Anesthesia on Visual Acuity in Planned Extracapsular Cataract Extraction
Authors: Brent B David , Singh Harcharan
Published: April 2021

ABSTRACT

To our knowledge, this is the first evaluation of the effect of retrobulbar anesthesia on visual acuity. We compared the preoperative best corrected near visual acuity of 30 consecutive patients undergoing planned extracapsular cataract extraction with their best corrected near visual acuity 10 minutes following successful retrobulbar anesthesia. The mean decrease in acuity was 2.83 lines on a Jaeger near card. Postinjection visual acuity did not change in four eyes. In general, the longer the globe axial length, the greater the decrease in visual acuity following retrobulbar block. There was no significant correlation between postinjection acuity and patient age or volume of anesthetic injected.
Removal of Lens Epithelial Cells by Dispersion With Enzymatic Treatment Followed by Aspiration
Authors: Nishi Okihiro , Nishi Kayo , Hikida Mitsushi
Published: April 2021

ABSTRACT

We conducted a preliminary trial of a method of lens epithelial cell removal in cataract surgery that combined mechanical and pharmaceutical treatments. The cells were first loosened from their junctional complexes with Dispase, a preparation of a neutral protease used for separating cells in tissue culture. To avoid intraocular tissue damage, the enzyme preparation was dissolved in sodium hyaluronate and injected into the capsular bag, which was carefully preserved during endocapsular cataract surgery. The cells were then removed by irrigation and aspiration. The results of experiments in vitro and in rabbits suggested that this procedure removed cells effectively, and, judging from the histopathologic examination, with negligible damage to the zonules or corneal endothelium.
The Effect of Transcutaneous Electrical Nerve Stimulation on Ocular Pain
Authors: Whitacre Marc M
Published: April 2021

ABSTRACT

The effect of transcutaneous electrical nerve stimulation (TENS) on pain originating in the eye was studied in 10 patients. All three patients subjected to TENS during panretinal photocoagulation reported marked reduction in pain. Three of five patients who had persistent pain following scleral buckling and/or vitrectomy reported partial or complete relief of pain during the application of TENS. One patient had equivocal relief of pain when TENS was used during retinal cryopexy; 1 patient with acute pain following paracentesis and 1 patient with persistent pain following cyclocryotherapy had no relief. Among those patients whose pain was reduced by TENS, referred brow pain was relieved more than globe pain.
Visual Improvement After Four Laser Treatments to Foveola for Choroidal Neovascular Membrane
Authors: Stephens Robert F , Daubert Jack S , El-choufi Leyla
Published: April 2021

ABSTRACT

With the advent of new laser technology and refined treatment techniques, it is possible that visual morbidity may be reduced by the treatment of subfoveolar choroidal neovascular membranes. This case report from our prospective study series describes an eye that required four monochromatic green subfoveolar treatments for an active choroidal neovascular membrane, which was ultimately eradicated. Even though the foveola was treated four times, the visual acuity improved from 20/200 preoperatively to 20/40 postoperatively. This case demonstrates that in carefully selected cases, even with multiple subfoveolar treatments, central visual acuity not only can be preserved, but also can actually be improved.
Role of the Vitreous in Posterior Segment Neovascularization in Central Retinal Vein Occlusion
Authors: Akiba Jun , Kado Masanori , Kakehashi Akihiro , Trempe Clement L
Published: April 2021

ABSTRACT

We retrospectively studied the relationship between the vitreous condition and the development of retinal or optic disc neovascularization in 60 eyes with central retinal vein occlusion associated with extensive retinal ischemia. At initial examination, 24 of 60 eyes (40%) with central retinal vein occlusion had complete posterior vitreous detachment, a prevalence significantly higher than in the fellow eyes. During a mean follow-up period of 43 months, 13 of 34 eyes (38%) without posterior vitreous detachment developed retinal or disc neovascularization, or both, but none of the 24 eyes with complete posterior vitreous detachment developed neovascularization (P < .001 ). Our results suggest that central retinal vein occlusion may induce the development of posterior vitreous detachment, and that posterior vitreous detachment may play a role in protecting eyes with central retinal vein occlusion from posterior segment neovascularization.
Intercapsular Cataract Extraction With Implantation of the Galand Disc Lens: A Retrospective Analysis in Patients With and Without Glaucoma
Authors: Gunning F P , Greve E L
Published: April 2021

ABSTRACT

We studied the results of intercapsular cataract extraction and implantation of the rigid Galand disc intraocular lens (IOL) in 164 cataract patients with and without glaucoma. Eighty-eight percent of the glaucomatous eyes and 98% of the eyes without glaucoma had a postoperative visual acuity of 20/40 or better after best-case analysis. Intercapsular bag placement appeared satisfactory in all but two cases, in which the IOL was slightly tilted. Cataract extraction favorably affected glaucoma control, especially in patients with angle-closure glaucoma (7.3 mm Hg intraocular pressure [IOP] reduction) and in those with primary open-angle glaucoma (2.6 mm Hg IOP reduction). The complications encountered, cystoid macular edema and hyphema, occurred in 1% and 0.5% respectively, and were not more frequent in the glaucoma subgroup. Posterior capsular opacification (30%) and inflammatory complications such as posterior synechiae (7.6%) and prepupillary fibrin (6%) were more often noted in the glaucomatous eyes. Pupillary capture or significant IOL decentration did not occur. We conclude that a circular type of IOL is the best currently available lens for use in glaucoma patients.
A Simple Method for Practicing Unimanual Pars Plana Vitrectomy With the Binocular Indirect Ophthalmoscope
Authors: Bloom Steven M , S Tiedeman MD James , Wyszynski Richard E , Brucker Alexander J
Published: April 2021

ABSTRACT

Bimanual vitrectomy has become the method of choice for performing closed vitrectomy. In certain situations, visualization is improved by using indirect ophthalmoscopy to see the vitrectomy instrument. A simple method using a +20.00-diopter condensing lens is described as a means of practicing the initially difficult unimanual technique, which requires working in an inverted operative field.
Subconjunctival Versus Intrascleral Mitomycin-C in Trabeculectomy
Authors: Tressler Charles S , Cyrlin Marshall N , Rosenshein Joseph S , Fazio Roselyn
Published: April 2021

* BACKGROUND AND OBJECTIVE: A ran domized prospective comparison of sub-Tenon's administration of mitomycin-C (MMC) with intrascleral administration of MMC in trabeculectomy was performed to determine whether intrascleral application is superior to the standard sub-Tenon's application.

* PATIENTS AND METHODS: Twenty-four eyes of 23 patients were randomized to treatment with MMC (0.27 mg/ml for 5 minutes). The route of administration was subconjunctival in group A and intrascleral in group B. Preoperative and postoperative visual acuity (VA), intraocular pressure (IOP), number of medications, and complications were compared between the two groups.

* RESULTS: There was no statistically significant difference between the two groups preoperatively regarding VA, IOP, and number of medications. Postoperatively, IOP and number of medications required had decreased significandy in both groups. A significandy larger number of postoperative procedures were required in group B to control IOP (group A = 3, group B = 14, P = .002).

* CONCLUSION: Both methods of MMC application significantly decreased the IOP and the number of medicines required to control IOP after trabeculectomy. The intrascleral use of MMC resulted in the need for more surgery postoperatively (P = .002).

[Ophthalmic Surg Lasers 1996;27:661-666.]