Vascular Changes Associated With Endophthalmitis.
Conditions: Endophthalmitis
Sponsor: Asociación para Evitar la Ceguera en México

Protocol ID: CVAE 01 
 
 
ASOCIACIÓN PARA EVITAR LA CEGUERA EN MÉXICO, I.A.P. 
HOSPITAL “DR. LUIS SÁNCHEZ BULNES” 
 
 
Academic Protocol 
 
 
 
Vascular changes associated with endophthalmitis.  
 
 
 
Protocol code: CVAE 01 
Version: 5 
 
 
PRINCIPAL INVESTIGATOR: 
 
Dr. Raúl Vélez Montoya 
 
Associated Investigators: 
Dra. Xiadani Lucero de la Rosa 
Dr. Benjamín Aboytes Ríos 
Dr. Ramsés Rosales Díaz 
 
 
 
 
 
 
 
 
 
 

Protocol ID: CVAE 01 
 
 
 
 
PRINCIPAL INVESTIGATOR: 
 
Dr. Raúl Vélez Montoya 
Attending Physician, Retina and Vitreous Department APEC 
Phone: 10841400   Ext: 1290 
E-mail:  rvelezmx@yahoo.com 
 
RESPONSIBLE RESEARCHER: 
Dr. Benjamín Aboytes Ríos 
Retina department fellow 
Phone: 4772329592  
E-mail: benaborivers@gmail.com 
 
RESEARCH ASSOCIATES 
Dr. Ramsés Rosales Díaz 
Retina department fellow 
Phone: 3111495039  
E-mail: ramses.rosales.diaz@gmail.com 
 
Dra. Xiadani Lucero de la Rosa 
Research Intern 
Phone: 5559440561 
E-mail: xldrg00@gmail.com 
 
 
 
 
 
 
 

Protocol ID: CVAE 01 
 
1.​ General Data:​
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1.1.​
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Title: Vascular changes associated with endophthalmitis ​ ​
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Area of study. Diagnostic Methods​ ​
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Probable start and end date of the survey: July 2024 – March 2026 
1.4.​
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Principal Author:  Dr. Benjamín Aboytes Ríos. 
1.5.​
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Co-investigators: Dr. Ramsés Rosales Díaz, Dr. Jans Fromow Guerra, Dra. 
Xiadani Lucero De la Rosa González 
1.6.​
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Principal investigator: Raúl Vélez Montoya. 
1.7.​
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Participating departments: Retina and Vítreous  
1.8.​
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Participating institutions: Asociación Para Evitar la Ceguera I.A.P​ ​
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2.​ Theoretical Framework​ ​
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Background: Bacterial endophthalmitis is a serious condition that can lead to 
irreversible vision loss and, if left untreated, can result in loss of the eye. The most 
common causes (although not limited to these) are: ocular surgery, invasive 
procedures, open ocular trauma with or without the presence of an intraocular 
foreign body. The risk of endophthalmitis after cataract surgery is low, with an 
incidence of 0.03% to 1.3% (2-6). The incidence of endophthalmitis following 
intravitreal injection does not vary significantly according to the anti-angiogenic 
agent used; the MARINA and ANCHOR trials reported an incidence of 0.05% for 
ranibizumab. In the VIEW trial for ranibizumab, it was 1,5%. (3-6)  This explains its 
probable relationship to the surgical procedure rather than the mechanism of the 
drug itself. (1) The current treatment paradigm is intravitreal antibiotic injections; 
however, this is changing towards early vitrectomy.  (1-7) 
 
Inflammation and tissue damage are mediated by the host immune response, the 
etiologic agent, ischemia, and drug toxicity.  
 
The inflammatory response in the posterior chamber leads to protein condensation 
in the vitreous humor, making it difficult to visualize the fundus and therefore to 
characterize the degree of damage to the retina and its vasculature.  
In 80% of patients, retinal vessels cannot be seen, and ultrasound is necessary to 
check for the initial presence of tractional membranes or retinal detachment. To this 
 

Protocol ID: CVAE 01 
 
day, the role that this increase in proteins, increased permeability, and blood stasis 
(Secondary to significant local inflammation) may have on the retinal vasculature 
remains unclear.  
 
Chronic degenerative diseases, through their respective pathophysiological 
processes, condition a systemic pro-inflammatory state. In cases where they exist 
as an underlying pathology, they can contribute to the presence of incipient vascular 
damage, making individuals more susceptible to damage to the microcirculation in 
ocular infectious processes, such as endophthalmitis.  
 
The clinical evolution of endophthalmitis depends on the intravitreal release of 
inflammatory cytokines, which promote neutrophil aggregation, leading to a variable 
degree of tissue necrosis and resulting in the presence of vitritis, perivascular 
exudate, vessel sheathing, diffuse patchy hemorrhages, phlebitis/periphlebitis, and 
occlusion of arteries proximal to the macula. However, these changes have been 
described as nonspecific; the main factor related to their presentation is unknown, 
and there is the possibility of undescribed damage (such as the presence of 
peripheral vascular lesions) 
 
Imaging techniques have undergone enormous advances in recent years, 
drastically improving the knowledge of the anatomy, functional, and metabolic state 
of the retina. (2) Optical coherence tomography (OCT) allows non-invasive 
cross-sectional imaging of the retina and choroid. Fluorescein angiography is the 
study of choice for the evaluation of the vascular system, and wide-field fundus 
photographs provide an overview of the integrity of the retina and its vasculature 
(7-9) 
 
Nowadays, there are no studies that describe vascular changes associated with 
endophthalmitis. However, when the previously mentioned techniques are used in 
combination, they can be used to evaluate the response to treatment and 
demonstrate ischemic changes or early vascular damage (11-14). Thus opening the 
possibility to implement early therapies that lead to a better final visual prognosis 
(12-14) 
 
 

Protocol ID: CVAE 01 
 
Justification: The implementation of multimodal imaging studies during the diagnosis and 
follow-up of patients with endophthalmitis may help to identify, characterize, and 
differentiate between changes associated with host immune response, drug toxicity, or 
ischemia, thus opening the possibility of the implementation of early treatments leading to 
a better final prognosis  
 
Problem statement  
 
Enophthalmitis is a serious condition that can result in both anatomical and functional 
consequences for the eye. Despite being an inflammatory condition of the eye, little is 
known about the vascular changes that occur secondary to endophthalmitis. For this 
reason, it has been decided to investigate whether angiographic changes correlate with 
visual prognosis in the short or medium term, as well as the comorbidities associated with 
each case. Do angiographic vascular changes correlate with visual prognosis?  
 
2.1.​
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Objectives and hypotheses​​
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2.1.1.1.​
General Objectives: To describe and investigate vascular 
changes associated with  exogenous endophthalmitis, as well as to 
create a photo library where they are evidenced  
2.1.1.2.​
Specific Objectives 
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1. ​
To demonstrate the presence or absence of perivascular 
exudate, vessel sheathing, phlebitis/periphlebitis, diffuse or 
localized hemorrhages, arteriovenous shunts, vascular closure 
zones, and neovessels, as well as their pattern of location (in the 
central or peripheral region of the retina) by means of fundus 
photography, optical coherence tomography, and fluorescein 
angiography  
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2. To identify and correlate the presence of incipient vascular 
damage that could make the microcirculation more susceptible to 
damage during ocular infectious processes in patients with 
significant personal pathological history  
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Protocol ID: CVAE 01 
 
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3. To describe vascular changes according to their probable 
etiology (ischemic, drug-mediated toxicity, and host immune 
response) 
using 
fundus 
photography, 
optical 
coherence 
tomography, and fluorescein angiography  
 
2.1.2.​ Hypothesis  
2.1.3.​ Null hypothesis 
-The incidence of vascular changes (exudates, hemorrhages, areas of 
capillary closure) is greater than 50% of cases, regardless of the 
pathogen or the treatment indicated  
 
2.1.3.1.​
Alternate hypothesis 
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The incidence of vascular changes (exudates, hemorrhages, 
areas of capillary closure) will be less than 50% of the cases, 
regardless of pathogen or treatment indicated.  
 
 
3.​ Study design  
According to the moment at which the information is collected. 
●​ Prospective - a study where the information will be collected in the future, after 
the beginning of the research  
 
3.1.​
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According to the number of times the primary variable of interest is 
measured or determined.  
●​ Longitudinal.- The primary variable of interest is measured more than once over 
time  
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3.2.​
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According to the researcher´s interference in the phenomenon being 
analyzed 
●​ Observational.-  The researcher only describes or measures the phenomenon  
 
3.3.​
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According to the analysis of the study population(S) 
●​ Descriptive.- The researcher only has a population and describes it  
 
 

Protocol ID: CVAE 01 
 
 
 
4.​ Methodology​
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4.1.​
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Place and duration  
The population will be patients of the retina and vitreous service of Asociación para 
Evitar la Ceguera en México, attended from July to December 2024, who have a 
complete clinical record (age, sex, pathological personal history, non-pathological 
personal 
history, 
heredofamilial 
history, 
ophthalmologic 
history, 
allergies, 
medications, ophthalmologic examination with visual acuity, intraocular pressure at 
each visit), signed informed consent and with a history of exogenous or endogenous 
endophthalmitis with clear resolution criteria and clear means one week and one 
month after meeting the resolution criteria to be able to perform fluorescein 
angiography at both visits. 
 
 
     4.2  Description 
 
Patients who meet the inclusion criteria will be invited to participate in the study, who will 
have a history of endophthalmitis and who have clear media (clear cornea, anterior 
chamber cellularity + or less, vitritis + or less), one week and one month after meeting the 
resolution criteria established by the Mexican Endophthalmitis Group. 
 
After signing the informed consent form  
A comprehensive ophthalmologic examination will be performed, including assessment of 
visual acuity and intraocular pressure.  
A fluorescein angiography will be performed one week after meeting resolution criteria, 
and one month later.  
Fluorescein 10% (10mg/ml) will be injected intravenously through a peripheral line.  
Fundus photographs will be taken with the Clarus 700 equipment 
The pictures will be analyzed in different phases and in different areas  
The changes will be compared at different times, one week after meeting the resolution 
criteria and one month later  
Consecutive recruitment will be done  
 

Protocol ID: CVAE 01 
 
The data will be stored in a table in Excel 2007  
 
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4.2.​
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Inclusion criteria 
●​ Patients with a history of endophthalmitis 
●​ Diagnosis of Endophthalmitis 
- Clinical symptoms: Pain, decrease in visual acuity, anterior chamber cells 
and/or vitreous turbidity, corneal edema, conjunctival hyperemia  
- Laboratory studies: B-mode USG and or positive culture 
●​ Patients who meet the endophthalmitis resolution criteria of the Mexican 
Endophthalmitis Study Group  
●​ Patients with previously signed informed consent  
 
 
4.3.​
       Exclusion criteria 
●​ Patients who have not signed the informed consent  
●​ Patients under 18 years.  
●​ Patients with endophthalmitis who do not meet the resolution criteria of the 
Mexican Endophthalmitis Study Group 
 
 
 
 
 
 
 
 
 
 
 
 
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Protocol ID: CVAE 01 
 
5.​ Study variables 
Variable 
name 
Independent 
or Dependent 
Nominal 
/ordinal/ 
dimensional 
Unit 
of 
measurem
ent 
Measurement 
instrument 
Time 
of 
measurement 
Visual acuity  
Independent 
Ordinal 
logMAR 
 
Snellen Chart 
At 
diagnosis, 
one week after 
resolution, and 
one month after 
Vascular 
changes 
in 
FAG (Areas 
of 
capillary 
closure)  
Independent 
Ordinal 
Disc areas 
Fluorescein 
angiography 
one week after 
resolution 
and 
one month after 
 
Vascular 
changes 
in 
FAG 
(Periphlebitis
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Independent 
Ordinal 
Presence 
or absence  
Fluorescein 
angiography 
with 
fluoroscein 
one week after 
resolution 
and 
one month after 
Vascular 
changes 
in 
FAG 
(Hejorrhages 
on staining) 
Independent 
Ordinal 
Presence 
or absence 
Fluorescein 
angiography 
with 
fluoroscein 
one week after 
resolution 
and 
one month after 
 
Vascular 
changes 
in 
FAG (Areas 
of leakage) 
Independent 
Ordinal 
Disc areas 
Fluorescein 
angiography  
one week after 
resolution 
and 
one month after 
 
Isolated body 
Independent 
Ordinal 
Presence 
or absence 
of 
microorgan
Medium 
Culture 
Single. 
When 
an 
organism 
grows 
in 
the 
culture 
 

Protocol ID: CVAE 01 
 
ism 
in 
culture 
 
Age 
Independent 
Dimensional 
Years 
completed 
Interrogation 
Visit 1 
 
Sex 
Independent 
Nominal, 
dichotomic 
Female/ 
Male 
Tab from the 
collection 
Unique  
 
5.1.1.​ Measuring Instrument  
Retinal Imaging and Analysis: Fluorescein angiography will be performed using the 
Clarus 700 Zeiss device (Serial # CL700-73467), with Software version 1.1.2.59261 and 
Digital Camera Magnification of 133°.​
Optical Coherence Tomography (OCT) will be performed using the HRA Spectralis 
Heidelberg, Serial # Spec-CAM-15095-S3610, with a 30° magnification and software 
version 7.0.6.0.​
 
 
5.1.2.​ Time of measurement. 
 
5.2.​
       Sample size. Description of the main maneuver(s)  
 
Best-Corrected Visual Acuity (BCVA) will be assessed according to the ETDRS 
guidelines. 
The test must be performed with the patient positioned 4 meters from the backlit panel, 
which must be calibrated to emit 85 cd/m². 
Testing will be conducted in both eyes (including both the randomized and 
non-randomized eye). Each eye must be tested using a chart with a different character 
layout to prevent patient memorization when such a chart variation is possible. If not, 
testing must begin with the study eye. 
 

Protocol ID: CVAE 01 
 
The total number of letters correctly identified by the patient must be recorded, 
along with the Snellen equivalent and LogMAR score. The test must be conducted 
under best-corrected visual conditions. 
The following conversion chart will be used to record best-corrected visual acuity. 
 
 
To measure Best-Corrected Visual Acuity (BCVA), the patient will be asked to identify 
the letters they can distinguish until they reach the line where they are unable to locate at 
least three optotypes correctly. The number of letters correctly identified will be 
recorded. 
Additionally, if using vision charts that do not begin at the 20/800 line (the point from 
which letter counting for ETDRS equivalence begins), the following adjustment will be 
made: a specific number of letters will be added to the patient's result. This procedure 
will be carried out by the retina fellow assigned to the case. The assessment will be 
performed at each visit (7 days and 1 month after meeting the inactivation criteria for 
endophthalmitis). 
 
 
Indirect Ophthalmoscopy 
A detailed examination of the retina will be performed. After pupillary dilation with TP 
Ofteno® (tropicamide 5% / phenylephrine 0.8%), an indirect ophthalmoscope and a 
 

Protocol ID: CVAE 01 
 
20D lens will be used for a comprehensive retinal evaluation. The brand and model of the 
instruments used will be at the discretion of the principal investigator. 
The structures to be evaluated include the optic nerve, retina, retinal vasculature, and 
transparency of the posterior segment media, among others. This procedure will be 
performed at all study visits by the designated clinical team. 
Spectral-Domain Optical Coherence Tomography (SD-OCT) 
OCT imaging will be performed using the HRA Spectralis Heidelberg, Serial # 
Spec-CAM-15095-S3610, with a Magnification of 30° and Software version 7.0.6.0. This 
will aid in evaluating the retinal condition, including central macular thickness and central 
retinal volume (commonly referred to as macular cube volume in OCT terminology). 
A technician or delegated personnel may carry out this procedure, and will be performed at 
all study visits. 
Fundus Photography and Fluorescein Angiography 
Fundus imaging will be performed using the Clarus 700 Zeiss, Serial 
#CL700-73467, Software version 1.1.2.59261, Digital Camera Magnification 133°. 
Images of the posterior pole and retinal periphery will be captured, providing a 
comprehensive view of retinal integrity, the optic nerve, and its vasculature. 
Fluorescein angiography will be performed subsequently to evaluate associated 
vascular changes. The patient must undergo an 8-hour fast and have pupillary 
dilation with TP Ofteno® (tropicamide 5% / phenylephrine 0.8%). The 
procedure involves preparing the patient with aseptic technique for an intravenous 
injection of fluorescein dye in an upper limb, followed by imaging with a fundus 
camera. 
It is not essential to use a device of a specific brand or model, as long as a system 
with equivalent specifications is used consistently for the same patient 
throughout the study. The procedure may be performed by a technician or 
 

Protocol ID: CVAE 01 
 
delegated personnel, and will be conducted at all study visits (7 days and 1 
month after meeting the inactivation criteria for endophthalmitis). 
Sample size  
 
    A review of hospital medical records was conducted to identify patients diagnosed with 
endophthalmitis from February 2024 to September 2024, resulting in a total of 57 
patients. 
Considering this data was collected over 8 months, a proportional extrapolation was 
made to estimate the number of cases in a 12-month calendar year, yielding 
approximately 86 patients. 
Based on this projection, we decided to use the sample size formula for proportion 
estimation, as our working hypothesis suggests that the incidence of vascular changes 
will be greater than 50%. 
The sample size was calculated using an online proportion estimation calculator: 
 
https://www.calculator.net/sample-size-calculator.html?type=1&cl=95&ci=5&pp=50
&ps=86&x=Calculate:  
 
 

Protocol ID: CVAE 01 
 
 
 
       
A total of 71 patients were included to achieve a 95% confidence interval, with a 
5% margin of error, a population proportion of 50%, and a total population 
size of 86 patients. 
We will calculate measures of central tendency (mean, median, and mode). 
Chi-square tests will be used for qualitative variables. 
Data will be analyzed using the SPSS software, version 25. 
 
Organization 
Human Resources: 
●​ Retina specialists affiliated with the Retina Service 
●​ Medical intern completing social service 
●​ Retina fellows 
●​ Nursing staff​
 
 

Protocol ID: CVAE 01 
 
Material Resources: 
●​ Computer 
●​ HRA Spectralis Heidelberg OCT, Serial #Spec-CAM-15095-S3610, 
Magnification 30°, Software version 7.0.6.0 
●​ Clarus 700 Zeiss, Serial #CL700-73467, Software version 1.1.2.59261, 
Digital Camera Magnification 133° 
●​ Dye 
●​ Needles 
●​ Plastic catheters 
●​ Vials of fluorescein 
 
 
5.3.​
Ethical Aspects ​
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This study was designed in accordance with the principles of the Declaration of Helsinki 
and in compliance with the guidelines for good clinical practice. All patients must sign an 
informed consent form prior to their inclusion in the study. Patient privacy will be protected 
at all costs, and only data relevant to this research will be collected.​
 
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5.4.​
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Schedule of activities 
 
 
Activities 
Septe
mber 
2024 
October
2024 
November 
2024 
Decemb
er 2024 
January 
2024 
Search 
for 
files 
X 
X 
 
 
 
Collation of 
inclusion 
criteria 
 
X 
X 
 
 
Excel 
database 
 
 
X 
X 
 

Protocol ID: CVAE 01 
 
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1.​ S. Montolío-Marzo Differential diagnosis of endophthalmitis after intravitreal drug 
injection 
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macular 
degeneration: 
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ARCH.SOC.ESP.OFTALMOL. 2023;9 8(7):367–376 
2.​ Levin HJ, Mehta MS, Storey PP, Patel SN, Kuley B, Wibbelsman TD, Obeid A, Garg S, 
Vander J, Dunn JP, Ho AC. Endophthalmitis following cataract surgery: visual outcomes, 
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doi: 10.1097/ICU.0000000000000951. Epub 2023 Mar 20. PMID: 36943680. 
3.​ Rahmani S, Elliott D. Postoperative endophthalmitis: a review of risk factors, 
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6.​ Shi SL, Yu XN, Cui YL, et al. Incidence of endophthalmitis after phacoemulsification 
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X 
 
Interpretatio
n   
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interpretatio
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and 
delivery 
of 
results 
 
 
 
 
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Protocol ID: CVAE 01 
 
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13.​ Zhuang H, Ding X, Gao F, Zhang T, Ni Y, Chang Q, Xu G. Optical coherence 
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