Comparison of Three Handheld Fundus Cameras for Assessment of the Vertical Cup-To-Disk Ratio.

Purpose To compare the quality of optic nerve photographs from three different handheld fundus cameras and to assess the reproducibility and agreement of vertical cup-to-disk ratio (VCDR) measurements from each camera. Methods Adult patients from a comprehensive ophthalmology clinic and an intravitreous injection clinic in northern Thailand were recruited for this cross-sectional study. Each participant had optic nerve photography performed with each of 3 handheld cameras: the Volk iNview, Volk Pictor Plus, and Peek Retina. Images were graded for VCDR in a masked fashion by two photo-graders and images with > 0.2 discrepancy in VCDR were assessed by a third photo-grader. Results A total of 355 eyes underwent imaging with three different handheld fundus cameras. Optic nerve images were judged ungradable in 130 (37%) eyes imaged with Peek Retina, compared to 36 (10%) and 55 (15%) eyes imaged with the iNview and Pictor Plus, respectively. For 193 eyes with gradable images from all 3 cameras, inter-rater reliability for VCDR measurements was poor or moderate for each of the cameras, with intraclass correlation coefficients ranging from 0.41 to 0.52. A VCDR ≥ 0.6 was found in 6 eyes on iNview images, 9 eyes on Pictor Plus images, and 3 eyes on Peek images, with poor agreement between cameras (e.g., no eyes graded as VCDR ≥ 0.6 on images from both the iNview and Pictor Plus). Conclusions Inter-rater reliability of VCDR grades from 3 handheld cameras was poor. Cameras did not agree on which eyes had large VCDRs.

Diagnostic accuracy of handheld fundus photography: A comparative study of three commercially available cameras.

The objective of this study was to compare the sensitivity and specificity of handheld fundus cameras in detecting diabetic retinopathy (DR), diabetic macular edema (DME), and macular degeneration. Participants in the study, conducted at Maharaj Nakorn Hospital in Northern Thailand between September 2018 and May 2019, underwent an ophthalmologist examination as well as mydriatic fundus photography with three handheld fundus cameras (iNview, Peek Retina, Pictor Plus). Photographs were graded and adjudicated by masked ophthalmologists. Outcome measures included the sensitivity and specificity of each fundus camera for detecting DR, DME, and macular degeneration, relative to ophthalmologist examination. Fundus photographs of 355 eyes from 185 participants were captured with each of the three retinal cameras. Of the 355 eyes, 102 had DR, 71 had DME, and 89 had macular degeneration on ophthalmologist examination. The Pictor Plus was the most sensitive camera for each of the diseases (73-77%) and also achieved relatively high specificity (77-91%). The Peek Retina was the most specific (96-99%), although in part due to its low sensitivity (6-18%). The iNview had slightly lower estimates of sensitivity (55-72%) and specificity (86-90%) compared to the Pictor Plus. These findings demonstrated that the handheld cameras achieved high specificity but variable sensitivities in detecting DR, DME, and macular degeneration. The Pictor Plus, iNview, and Peek Retina would have distinct advantages and disadvantages when applied for utilization in tele-ophthalmology retinal screening programs.

Accuracy of computer-assisted vertical cup-to-disk ratio grading for glaucoma screening.

PURPOSE: Glaucoma screening can be performed by assessing the vertical-cup-to-disk ratio (VCDR) of the optic nerve head from fundus photography, but VCDR grading is inherently subjective. This study investigated whether computer software could improve the accuracy and repeatability of VCDR assessment. METHODS: In this cross-sectional diagnostic accuracy study, 5 ophthalmologists independently assessed the VCDR from a set of 200 optic disk images, with the median grade used as the reference standard for subsequent analyses. Eight non-ophthalmologists graded each image by two different methods: by visual inspection and with assistance from a custom-made publicly available software program. Agreement with the reference standard grade was assessed for each method by calculating the intraclass correlation coefficient (ICC), and the sensitivity and specificity determined relative to a median ophthalmologist grade of ≥0.7. RESULTS: VCDR grades ranged from 0.1 to 0.9 for visual assessment and from 0.1 to 1.0 for software-assisted grading, with a median grade of 0.4 for each. Agreement between each of the 8 graders and the reference standard was higher for visual inspection (median ICC 0.65, interquartile range 0.57 to 0.82) than for software-assisted grading (median ICC 0.59, IQR 0.44 to 0.71); P = 0.02, Wilcoxon signed-rank test). Visual inspection and software assistance had similar sensitivity and specificity for detecting glaucomatous cupping. CONCLUSION: The computer software used in this study did not improve the reproducibility or validity of VCDR grading from fundus photographs compared with simple visual inspection. More clinical experience was correlated with higher agreement with the ophthalmologist VCDR reference standard.

Sensitivity and Specificity of Potential Diagnostic Features Detected Using Fundus Photography, Optical Coherence Tomography, and Fluorescein Angiography for Polypoidal Choroidal Vasculopathy.

Importance: The use of indocyanine green angiography (ICGA) is a criterion standard for diagnosing polypoidal choroidal vasculopathy (PCV), an endemic and common cause of vision loss in Asian and African individuals that also presents in white individuals. However, the use of ICGA is expensive, invasive, and not always available at clinical centers. Therefore, knowing the value of certain features detected using fundus photography (FP), optical coherence tomography (OCT), and fluorescein angiography (FA) to diagnose PCV without ICGA could assist ophthalmologists to identify PCV when ICGA is not readily available. Objective: To explore the sensitivity, specificity, and predictive accuracy of potential diagnostic features detected using FP, OCT, and FA in diagnosing PCV without ICGA. Design, Setting, and Participants: Deidentified images of FP alone, OCT alone, and FA alone were graded by 3 retina specialists masked to ICGA findings for potentially diagnostic features of PCV prespecified before grading compared with the criterion standard grading of 2 other retina specialists with access simultaneously to FP, OCT, FA and ICGA. Specialists graded images of 124 eyes of 120 patients presenting between January 1, 2013, and December 31, 2016, with newly identified serous or serosanguinous maculopathy who had undergone FP, OCT, FA, and ICGA before treatment at a large referral eye center in Thailand. Main Outcomes and Measures: Sensitivity, specificity, positive predictive value, negative predictive value, and predictive accuracy from the area under the receiver operating characteristic curve (AUC). Results: The mean (SD) age of the patients was 57.7 (12.6) years, 52 were women, 68 were men, and the diagnosis (from ICGA) was PCV for 65 eyes (52.4%), central serous chorioretinopathy for 45 eyes (36.3%), and typical neovascular age-related macular degeneration for 12 eyes (9.7%). With the use of FP, a potential diagnostic feature for PCV was notched or hemorrhagic pigment epithelial detachment (AUC, 0.77; 95% CI, 0.70-0.85). With the use of OCT, potential diagnostic features for PCV were pigment epithelial detachment notch (AUC, 0.90; 95% CI, 0.85-0.96), sharply peaked pigment epithelial detachment (AUC, 0.86; 95% CI, 0.80-0.92), and a hyperreflective ring (AUC, 0.86; 95% CI, 0.80-0.92). When at least 2 of these 4 signs were present, the AUC was 0.93 (95% CI, 0.89-0.98), with a sensitivity of 0.95 (95% CI, 0.87-0.99), a specificity of 0.95 (95% CI, 0.82-0.97), a positive predictive value of 0.92 (95% CI, 0.83-0.97), and a negative predictive value of 0.95 (95% CI, 0.86-0.99). Conclusions and Relevance: These data suggest that the potential diagnostic features detected using FP and OCT provide high sensitivity and specificity for a diagnosis of PCV, especially when at least 2 of 4 highly suggestive signs are present.

Characteristics and Outcomes of Pars Plana Vitrectomy for Proliferative Diabetic Retinopathy Patients in a Limited Resource Tertiary Center over an Eight-Year Period.

PURPOSE: To report characteristics and visual results in patients with PDR-associated complications following pars plana vitrectomy (PPV) in a tertiary center over an eight-year period. METHODS: Medical records of diabetic retinopathy patients receiving PPV between January 2007 and December 2014 for PDR-related complications were reviewed. RESULTS: A total of 890 consecutive PDR patients were included in the study. PPVs were performed for tractional retinal detachment (36.6%), persistent vitreous hemorrhage (VH) (35.4%), combined tractional and rhegmatogenous retinal detachment (14.5%), and vitreoretinal abnormalities (13.5%), respectively. Preoperative intravitreal bevacizumab injection (IVB) within two weeks prior to PPV and 23G vitrectomy systems was found to decrease the risk for intraoperative retinal break development (P=0.045 and P=0.015, respectively). The incidence of early dense postoperative VH decreased significantly with the administration of preoperative or intraoperative IVB at the end of PPV. Postoperative visual results significantly correlated with the initial visual acuity level, intraoperative retinal break development, and retained silicone oil tamponade at the final visit (P < 0.001, P=0.040, and P=0.044, respectively). Administration of adjuvant IVB either before or at the end of PPV had no significant association with the final visual outcomes. CONCLUSIONS: This study reported an improvement in visual acuity in nearly half of patients receiving PPV for PDR-associated complications in a limited resource center. The incidence of intraoperative retinal break and early postoperative VH decreased significantly with the application of IVB injections. Poor final visual outcomes were related to the lower initial visual acuity levels, intraoperative retinal breaks, and postoperative retained silicone oil.

Visual acuity outcomes in cytomegalovirus retinitis: early versus late diagnosis.

AIMS: To determine if early dilated fundus examination for cytomegalovirus (CMV) retinitis leads to better visual outcomes in areas with limited HIV care, where patients may have long-standing retinitis before they are diagnosed with HIV. METHODS: Twenty-four eyes of 17 patients with CMV retinitis who were seen at an urban HIV clinic in Chiang Mai, Thailand, were included in this retrospective cohort study. Participants were divided into two groups based on the amount of time from the first documented CD4 count below 100 cells/mm3 to the first eye examination for CMV retinitis. Average visual acuity in each group was calculated at the time CMV retinitis was first detected, and then at 3, 6 and 12 months after diagnosis. RESULTS: The group of patients who received an eye examination within approximately 4 months of the initial low CD4 count measurement had better baseline visual acuity (median 20/30,IQR 20/20 to 20/60) compared with patients who presented later (median 20/80, 20/60 to hand motion); p=0.03). Visual acuity did not change significantly during the 12-month study period in either the early group (p=0.69) or late group (p=0.17). CONCLUSION: In this study, patients who were examined sooner after a low CD4 count had better vision than patients who were examined later. Routine early screening of patients with CD4 counts under below 100 cells/mm3 may detect earlier disease and prevent vision loss.

Color Fundus Photography, Optical Coherence Tomography, and Fluorescein Angiography in Diagnosing Polypoidal Choroidal Vasculopathy.

PURPOSE: To determine sensitivity and specificity of polypoidal choroidal vasculopathy (PCV) diagnosis using color fundus photography (CFP), optical coherence tomography (OCT), and fundus fluorescein angiography (FFA) without indocyanine green angiography (ICGA). DESIGN: Validity analysis. METHODS: Treatment-naïve eyes with serous/serosanguinous maculopathy undergoing CFP, OCT, FFA, and ICGA imaging before treatment at a university hospital in Thailand (January 1, 2013 to June 30, 2015) were identified. Images of each subject were categorized into 4 sets (set A: CFP; set B: CFP+OCT; set C: CFP+FFA; set D: CFP+OCT+FFA). Six graders, 3 from Thailand (PCV endemic area) and 3 from the United States (nonendemic area), individually reviewed each set (without ICGA), and determined if the presumed diagnosis was PCV. In parallel, 2 other graders confirmed if each case had PCV or not using EVEREST criteria (including ICGA). Sensitivity and specificity of a PCV diagnosis with each set (without ICGA) were analyzed compared with diagnoses including ICGA. RESULTS: Of 119 study eyes (113 subjects, 57% male, mean age ± SD 59.9 ± 13.8 years), definite PCV diagnosis was 40.3%. Sensitivity of sets A, B, C, D: 0.63 (95% confidence interval [CI]: 0.47-0.76), 0.83 (95% CI: 0.69-0.92), 0.54 (95% CI: 0.39-0.68), 0.67 (95% CI: 0.51-0.79); specificities: 0.93 (95% CI: 0.84-0.97), 0.83 (95% CI: 0.72-0.91), 0.97 (95% CI: 0.89-0.99), 0.92 (95% CI: 0.82-0.97); accuracies: 0.81 (95% CI: 0.73-0.88), 0.83 (95% CI: 0.76-0.90), 0.79 (95% CI: 0.73-0.87), 0.82 (95% CI: 0.74-0.88). Discrepancies between Thai and US graders existed through sets A, C, and D. CONCLUSIONS: These data suggest that without ICGA, fundus photography combined with OCT provides high sensitivity and high specificity to diagnose PCV; adding FFA does not improve accuracy.

Incidence of short-term complications and associated factors after primary trabeculectomy in Chiang Mai University Hospital.

BACKGROUND: To determine the incidence of early postoperative complications and associated factors after primary trabeculectomy in Thai glaucoma patients. DESIGN: This was a retrospective observational study performed in Chiang Mai University Hospital. PARTICIPANTS: One hundred and eighteen glaucoma patients participated in the study. METHODS: All glaucoma patients underwent primary trabeculectomy with mitomycin C (MMC) using fornix-based conjunctival flap technique between December 2011 and May 2013. Surgical complications during the first 3 months of follow-up were recorded, and associated risk factors were analyzed. MAIN OUTCOME MEASURES: The incidence of posttrabeculectomy complications was the main outcome measure. RESULTS: One hundred and eighteen eyes of 118 patients were included. Early postoperative complications developed in 55 eyes (56.7%). Complications included hypotony (25 eyes, 27.2%), serous choroidal detachment (CD) (14 eyes, 15.6%), subconjunctival hemorrhage (12 eyes, 13.0%), hyphema (11 eyes, 12.4%), bleb leak (8 eyes, 8.8%), encapsulated bleb (2 eyes, 2.2%), aqueous misdirection (1 eyes, 1.1%), corneal epithelial defect (1 eyes, 1.1%), and overfiltration (1 eyes, 1.1%). There were no reported cases of endophthalmitis or blebitis. Hypotony was associated with serous CD (P = 0.006), and hyphema was associated with neovascular glaucoma (NVG) patients (P = 0.009). NVG was not associated with the increased rate of surgical failure (P = 0.083). CONCLUSIONS: The incidence of early complications after first-time trabeculectomy with MMC was high (56.7%) in this Thai clinic setting, but most were transient and self-limited conditions. The correlations between hypotony and CD as well as hyphema and NVG were compatible with the previous studies.