Correction to: Real-World Safety of Intravitreal Bevacizumab and Ranibizumab Treatments for Retinal Diseases in Thailand: A Prospective Observational Study.

The Open Access license, which previously read.

Real-World Safety of Intravitreal Bevacizumab and Ranibizumab Treatments for Retinal Diseases in Thailand: A Prospective Observational Study.

BACKGROUND: There is very limited evidence examining serious systemic adverse events (SSAEs) and post-injection endophthalmitis of intravitreal bevacizumab (IVB) and intravitreal ranibizumab (IVR) treatments in Thailand and low- and middle-income countries. Moreover, findings from the existing trials might have limited generalizability to certain populations and rare SSAEs. OBJECTIVES: This prospective observational study aimed to assess and compare the safety profiles of IVB and IVR in patients with retinal diseases in Thailand. METHODS: Between 2013 and 2015, 6354 patients eligible for IVB or IVR were recruited from eight hospitals. Main outcomes measures were prevalence and risk of SSAEs, mortality, and endophthalmitis during the 6-month follow-up period. RESULTS: In the IVB and IVR groups, 94 and 6% of patients participated, respectively. The rates of outcomes in the IVB group were slightly greater than in the IVR group. All-cause mortality rates in the IVB and IVR groups were 1.10 and 0.53%, respectively. Prevalence rates of endophthalmitis and non-fatal strokes in the IVB group were 0.04% of 16,421 injections and 0.27% of 5975 patients, respectively, whereas none of these events were identified in the IVR group. There were no differences between the two groups in the risks of mortality, arteriothrombotic events (ATE), and non-fatal heart failure (HF). Adjustment for potential confounding factors and selection bias using multivariable models for time-to-event outcomes and propensity scores did not alter the results. CONCLUSIONS: The rates of SAEs in both groups were low. The IVB and IVR treatments were not associated with significant risks of mortality, ATE, and non-fatal HF. TRIAL REGISTRATION: Thai Clinical Trial Registry identifier TCTR20141002001.

Enhanced depth imaging spectral-domain optical coherence tomography of the choroid in Thai population.

OBJECTIVE: To examine subfoveal choroidal thickness (SFCT) in Thai population using enhanced depth imaging spectral- domain optical coherence tomography (EDI-OCT) and to study its correlation with foveal retinal pigment epithelium thickness (FRPE), central neurosensory retinal thickness (CNRT), age, and refraction. MATERIAL AND METHOD: Four hundred eighty eyes from 240 subjects without glaucoma, retinal, or choroidal diseases underwent scanning of the retina and choroid using EDI-OCT SFCT FRPE, and CNRT measurements were based on the 1:1 micron images and wereperformed by two independent observers. The reliability ofmeasurements between the observers was evaluated by intraclass correlation coefficient (ICC). The correlations of SFCT with FRPE, CNRT, age, and refractive error were analyzed RESULTS: The mean age of the subjects was 36.22 years (range 20-81years). The means (95% reference intervals) of SFCT, CNRT andFRPE were 294.02 µm (137.14-450.90 µm), 174.22 µm (141.82-206.62 µm), and 41.94 µm (34.65-49.23 µm), respectively. SFCT and CNRThad excellent reliability between the two observers [ICC = 0.947 (95% CI, 0.918-0.963) and 0.929 (95% CI, 0.906-0.945), respectively], while FRPE showed good reliability [ICC = 0. 729 (95% CI, 0.637-0.793)]. SFCT had a low positive correlation with FRPE (r = 0.179, p<0. 0001) but not with CNRT (p = 0.317). SFCT showed a positive correlation with refraction (r = 0.338, p<0.0001) and a negative correlation with age (r = -0.166, p<0.0001). Regression analysis suggested that the SFCT decreased by 12.23 pm per one decade oflife and by 11.42 pm per one diopter of myopia. CONCLUSION: Normal values of SFCT in Thai population were obtained SFCT significantly decreased with older age and higher myopia. SFCT was associated with FRPE, reflecting the same vascular supply of the choroid and retinal pigment epithelium. When measured with our technique based on the 1:1 micron images, the reliability ofSFCT measurement was very high despite highly morphologic inter-individual variations.

Optic atrophy after anti-vascular endothelial growth factor injection in diabetic patients with proliferative diabetic retinopathy.

OBJECTIVE: To study the prevalence of optic atrophy in patients with proliferative diabetic retinopathy (PDR) who underwent intravitreal bevacizumab injection and risk factors associated with optic atrophy. MATERIAL AND METHOD: A retrospective case control study enrolled 269 cases (394 eyes) of patients with PDR, in which 166 cases (219 eyes) received intravitreal bevacizumab injection. Associated factors such as type of DM, hemoglobin A1c level, hypertension, hypercholesterolemia, chronic kidney disease, previous intravitreal surgery retinal detachment, and vitreous hemorrhage were recorded. Criteria for diagnosis of optic atrophy were decreased visual acuity, pale optic disc and decreased nerve fiber layer thickness, which was measured by Stratus optical coherence tomography (OCT). The association between intravitreal bevacizumab injection and optic atrophy was analyzed by multiple logistic regression. RESULTS: Two hundred sixty nine patients with PDR, consisting of 166 patients with intravitreal bevacizumab injection and 103 cases without bevacizumab injection. Optic atrophy was found in 11.4% (25/219 eyes) and 8% (14/175 eyes) respectively. There was no evidence that intravitreal bevacizumab injection and associated systemic diseases were related to optic atrophy. The risk factor that was related to optic atrophy was previous intravitreal surgery (adjusted odds ratio (OR), 2.57 [95% CI, 1.13, 5.84], p = 0.024). CONCLUSION: Anti-VEGF (bevacizumab) does not increase the risk of optic atrophy. The ophthalmologists should be aware of subsequent optic atrophy development in patients with PDR who undergo surgical intervention.

Causes of visual impairment in Thai diabetic patients in the visual rehabilitation clinic.

BACKGROUND: Visual disability from diabetic retinopathy is one of many public health problems. Knowing the causes of blindness and low vision in diabetic patients will help in policy planning in order to reduce diabetic complications and prevent blindness. OBJECTIVE: To study the causes of visual impairment, blindness and related factors in diabetic patients who registered at the visual rehabilitation clinic, Siriraj Hospital, Mahidol University, Bangkok. MATERIAL AND METHOD: A retrospective study of 133 diabetic patients who registered at the visual rehabilitation clinic between January 2007 and December 2010 was conducted. The patients were divided into 2 groups: a low vision group (VA in the better eye < 6/18-3/60) and a blindness group (VA in the better eye < 3/60--No light perception). The history of diabetic mellitus, associated systemic diseases, laboratory investigations, ocular changes and treatment were recorded. The causes of visual impairment and blindness were collected and analyzed. RESULTS: Of a total of 133 diabetic patients, 93 cases (69.9%) were in a low vision group and 40 cases (30.1%) were in a blindness group. The causes of visual impairment were proliferative diabetic retinopathy (84.6%), retinal detachment (37.2%), macular edema and scar (25.9%), optic atrophy (143%), neovascular glaucoma (11.7%) and vitreous hemorrhage (4.9%). Tractional retinal detachment (p-value < 0.001) and optic atrophy (p-value = 0.021) were the associated factors causing blindness in visual disability patients with statistical significance. Optic atrophy (38 eyes) occurred post vitrectomy in 19 eyes. CONCLUSION: Visual disability in diabetic patients is caused by the complications of diabetic retinopathy and its management. The prevention of disease progression, especially macular edema and proliferative diabetic retinopathy, will decrease the rate of visual impairment and blindness.

Visual outcome and prognostic factors in posterior segment intraocular foreign bodies.

OBJECTIVE: To identify the prognostic factors that predict visual outcome in eyes with penetrating ocular injuries with retained intraocular foreign bodies (IOFBs). DESIGN: Retrospective cases series MATERIAL AND METHOD: The authors reviewed the records of 228 patients who had penetrating eye injuries with retained posterior segment IOFBs managed at Siriraj Hospital between June 1995 and February 2008. One hundred and forty-one patients (61.8%) were included in the present study. Associations between final visual outcome and various pre-operative and post operative variables were statistically analyzed. RESULTS: After a mean follow-up of 10.4 +/- 7.7 months, 68 eyes (48.2%) achieved visual acuity of 6/18 or better The final visual acuity ranged between 6/24 and 6/60 in 22 eyes (15.6%) and 51 eyes (36.2%) had visual acuity less than 6/60. Final visual acuity significantly depended on initial visual acuity (p = 0.002), size of entry wound (p = 0.020), size of foreign body (p = 0.018), presence of vitreous hemorrhage (p = 0.014), retinal detachment (p = 0.026) and endophthalmitis (p < 0.0001). CONCLUSION: Visual outcome in penetrating ocular injuries with retained IOFBs was affected by initial visual acuity, size of entry wound, size of foreign body, vitreous hemorrhage, retinal detachment and endophthalmitis. These factors may be helpful for pre-operative counseling and predicting the final visual outcome.

Risk factors for retinal breaks in patients with symptom of floaters.

OBJECTIVE: To identify the risk factors of retinal breaks in patients with the symptom of floaters, and to determine the association between those risk factors and retinal breaks. MATERIAL AND METHOD: A retrospective analytic study of 184 patients (55 males and 129 females) that included 220 eyes was conducted. Patient information such as age, symptoms (multiple floaters, flashing), duration of symptom, refractive error, history of cataract surgery, family history of retinal detachment, and complete eye examination were recorded. The patients were divided into two groups, the first group (control group) had symptoms of floaters and no retinal breaks, the second group (retinal breaks group) had symptoms of floaters with retinal breaks. Chi-square test, and the multiple logistic regression were used for statistical analysis. RESULTS: Two hundred twenty eyes, 175 eyes of the control group and 45 eyes of the retinal breaks group were examined and included in this study. The multiple logistic regression analysis revealed that patients with multiple floaters, and floaters and flashing increased the risk of retinal breaks to 5.8 and 4.3 times, respectively, when compared to patients with single floater or floaters alone. Lattice degeneration increased the risk of retinal breaks to 5.9 times when compared to eyes that did not have lattice degeneration. CONCLUSION: Multiple floaters, flashing and lattice degeneration are risk factors of retinal breaks in patients with symptoms of floaters. Therefore, it is important for the ophthalmologists to be aware of these risk factors and the patients at risk should have follow-up examinations.

Nonmydriatic digital retinal images for determining diabetic retinopathy.

OBJECTIVE: To evaluate the efficacy of nonmydriatic digital retinal images for determining diabetic retinopathy. MATERIAL AND METHOD: Single field 45-degree digital retinal images of 225 eyes from 142 diabetic patients were obtained with a nonmydriatic camera. The images were diagnosed and graded by a general ophthalmologist. These results were compared with clinical diagnosis obtained by retinal specialists, after examination by using biomicroscope with plus lens and indirect ophthalmoscope of the patients. International clinical diabetic retinopathy disease severity scale was used for grading diabetic retinopathy in all cases. RESULTS: Presence of diabetic retinopathy was detected in 70 eyes (31.1%). The sensitivity and specificity for determining diabetic retinopathy was 68.57% (95%CI 57.00-78.20) and 92.25% (95%CI 87.00-95.50), respectively. The positive predictive value and negative predictive value was 80.00% (95%CI 68.20-88.20) and 86.67% (95%CI 80.60-91.00). Overall accuracy was 84.89%. CONCLUSION: Single field 45-degree nonmydriatic digital retinal images were limited by fair sensitivity for determining diabetic retinopathy although overall accuracy from the present study was relatively high. Upcountry, this tool might facilitate increased access of diabetic patients for eye evaluation but cannot replace standard eye examination.

Feasibility study on computer-aided screening for diabetic retinopathy.

PURPOSE: To conduct a feasibility study of computer-aided screening for diabetic retinopathy by developing a computerized program to automatically detect retinal changes from digital retinal images. METHODS: The study was carried out in three steps. Step 1 was to collect baseline retinal image data of 600 eyes of normal subjects with normal fundi and data of 300 eyes of diabetic patients with diabetic retinopathy. All data were recorded by digital fundus camera. Step 2 was to analyse all retinal images for normal and abnormal features. By this method, the automated computerized screening program was developed. The program preprocesses colour retinal images and recognizes the main retinal components (optic disc, fovea, and blood vessels) and diabetic features such as exudates, haemorrhages, and microaneurysms. All of the accumulated information is interpreted as normal, abnormal, or unknown. Step 3 was to evaluate the sensitivity and specificity of the computerized screening program by testing the program on diabetic patients and comparing the program's results with the results of screening by retinal specialists. RESULTS: Diabetic patients (182 patients, 336 eyes) were examined by retinal specialists; 221 eyes had a normal fundus and 115 eyes had nonproliferative diabetic retinopathy. Digital retinal images were taken of these 336 eyes and interpreted by the automated screening program. The program had a sensitivity and specificity of 74.8% and 82.7%, respectively. CONCLUSIONS: The automated screening program was able to differentiate between the normal fundus and the diabetic retinopathy fundus. The program may be beneficial for use in screening for diabetic retinopathy. Further development of the program may provide higher sensitivity.

Pseudophakic retinal detachment with ruptured posterior lens capsule.

The relationship between retinal detachment and posterior lens capsule rupture in pseudophakic patients was studied. Records of patients with pseudophakic retinal detachment who were admitted to Siriraj Hospital from 1992 to 2004 were reviewed. The patients were divided into 2 main groups: 1) The study group (pseudophakic retinal detachment) 79 eyes (78 cases) which was subdivided into group 1a) pseudophakic retinal detachment with intact posterior lens capsule (50 eyes), and group 1b) pseudophakic retinal detachment with ruptured posterior lens capsule (29 eyes); 2) The control group 99 eyes (90 cases) which was subdivided into group 2a) pseudophakic patients with intact posterior lens capsule (83 eyes), and group 2b) pseudophakic patients with ruptured posterior lens capsule (16 eyes). The relationship between pseudophakic retinal detachment and posterior lens capsule rupture was analyzed by Chi-square test, and risk factors were analyzed by multiple logistic regression. Retinal detachment in pseudophakic patients was found more often in males more than in females, and the average age was 57.9 +/- 11.8 years, the retinal detachment was related to posterior lens capsule rupture (p = 0.003). Patients with pseudophakic retinal detachment with a ruptured posterior lens capsule had a risk 5.7 times greater than pseudophakic patients with an intact posterior lens capsule (adjusted Odds ratio = 5.716, 95% CI = 2.118-15.427). The present study showed that posterior lens capsule rupture increased the risk of retinal detachment. Ophthalmologists should be aware of retinal detachment development after YAG capsulotomy, especially in patients who have other risk factors such as myopia, lattice degeneration, retinal break, or previous retinal detachment surgery.

Evaluation of screening tests and prevalence of glaucoma: integrated health research program for the Thai elderly.

The purposes of this study were to evaluate the accuracy of glaucoma screening tests and to assess the prevalence of glaucoma in an elderly Thai population over 60 years of age. This was a cross-sectional study. 3706 subjects were recruited from 33 communities in the vicinity of Siriraj Hospital. All received an eye examination from ophthalmologists and general practitioners including visual acuity, Schiotz tonometry and optic disc evaluation in their residential communities. Subjects who were suspected of having glaucoma were re-examined at the Glaucoma Clinic, Siriraj Hospital. They were then classified as having definite glaucoma of a specific type or as not having glaucoma. The overall prevalence of glaucoma was 6.1 per cent (128/2092). The percentages of primary open angle glaucoma, primary angle closure glaucoma, normotension glaucoma and secondary glaucoma were 47.7 per cent, 41.4 per cent, 9.4 per cent, and 1.6 per cent respectively. The sensitivity and specificity of the screening tests performed by ophthalmologists were 100 per cent and 97.2 per cent and those performed by general practitioners were 21.7 per cent and 96.5 per cent.