RECENT NOTEWORTHY STUDIES TO STIMULATE DISCUSSION AND DEBATE
▪ Oral FA vs. OCT. Italian and US doctors collaborated on research that found oral fluorescein angiography was superior to SD-OCT in detecting macular edema.
The authors conducted a retrospective review of 1,928 eyes that underwent both SD-OCT and angiography using oral fluorescein. They saw no allergic reactions, and gastric discomfort was extremely rare (<1%).
An overwhelming majority (95.4%) of the eyes showed agreement between the two imaging modalities, with FA showing superior detection of macular edema to SD-OCT. The modalities detected wet AMD equally well, while SD-OCT outperformed oral FA in detecting macular holes.
Based on the ability of FA to detect subtle macular edema that SD-OCT can miss, the authors suggested that combined use of both modalities could comprehensively detect macular edema.
Barteselli G, Chhablani J, Lee SN, et al. Safety and efficacy of oral fluorescein angiography in detecting macular edema in comparison with spectral-domain optical coherence tomography. Retina. 2013;33:1574-1583.
▪ Retinal hemorrhage in children. Doctors at several hospitals in the UK conducted a prospective trial in children admitted to emergency rooms, finding that retinal hemorrhages were both relatively rare and not extensive.
Of 159 children enrolled in the study, 24 had retinal hemorrhage. The majority (79.1%) were in zone 1 or zones 1 and 2, with no hemorrhages reported in zone 3. The severity was mild or moderate, with no severe cases.
The more extensive hemorrhages occurred entirely in children with blood diseases, including leukemia, with two exceptions: one child who was injured in a car accident, and one who suffered a fall down stairs. None of the more extensive cases was the result of abuse.
The study is significant in finding that retinal hemorrhages were not more commonly associated with abuse. As a result, the authors encourage emergency room doctors to screen children presenting with retinal hemorrhages for blood disorders, as well as for abuse.
Adams GGW, Agrawal S, Sekhri R, Peters MJ, Pierce CM. Appearance and location of retinal haemorrhages in critically ill children. Br J Ophthalmol. 2013;97:1138-1142.
▪ Platelets in RVO. Are platelet volumes higher in patients with retinal vein occlusions? To answer that question, ophthalmologists in Turkey undertook a retrospective study.
Figure. Fluorescein angiography of an eye with CRVO, with OCT in inset.
COURTESY: TEERAPAT JITTPOONKUSON, MD, PATRICIA M.T. GARCIA, MD, GENNADY LANDA, MD, AND RICHARD B. ROSEN, MD
Examining the cases of 193 patients with RVO and 83 healthy controls, the authors found that the mean platelet volume (MPV) in RVO patients was significantly higher (8.19 ±1.22 femtoliters [fL]) compared to the controls (7.68 ±1.11 fL). However, they detected no difference in absolute platelet counts, indicating larger platelet size in the RVO patients.
Also, MPV was an independent predictor of RVO. The results suggested MPV might contribute to the pathogenesis of RVO, although the limitations of a retrospective study apply.
Sahin A, Sahin M, Yüksel H, et al. The mean platelet volume in patients with retinal vein occlusion. J Ophthalmol. 2013;236371.
▪ Delayed PPV for lens fragments. To compare VA outcomes between same-day and delayed pars plana vitrectomy to remove retained lens fragments following phaco, doctors at the Bascom Palmer Eye Institute performed a retrospective case series of 569 eyes.
One hundred seventeen eyes underwent same-day PPV vs 131 patients having surgery at 1 week and 321 patients at >1 week (median 22 days). After a median follow-up of 8 months, 61%, 63% and 56% of patients, respectively, had BCVA of ≥20/40. Conversely, 16%, 15% and 21%, respectively, had BCVA ≤20/200.
Given the small differences, which were not statistically significant, the authors recommended that surgery not be rushed for logistic reasons. Although the data were retrospective, the outcomes within the three time frames were equivalent.
Modi YS, Smiddy WE, Murray TG, Feuer W, Flynn HW Jr. Retained lens fragments after cataract surgery: outcomes of same-day versus later pars plana vitrectomy. Am J Ophthalmol. 2013;156:454-459.
▪ SD-OCT and GA prediction. Distinct changes on OCT were associated with more rapid enlargement of GA, larger lesion size and multifocal atrophy, according to a recent study by retinal physicians in South Korea and the Duke University Medical Center.
Forty-three eyes with GA from AMD underwent SD-OCT and FAF imaging. The authors measured GA enlargement by FAF over 24 weeks, with morphology tracked on OCT.
The authors found outer retinal tubulations and elevation of the RPE were correlated with faster enlargement of GA, as well as with larger legion size. Moreover, hyper-reflective plaques in the outer retina more frequently accompanied multifocal GA.
The authors believe SD-OCT could be a tool to predict GA progression in conjunction with FAF. RP