Faculty Bibliography

BACKGROUND AND OBJECTIVE: To evaluate subfoveal choroidal thickness (CT) and the extent of outer retinal disruption in patients with macular telangiectasia type 2 (MacTel2) compared with healthy eyes. PATIENTS AND METHODS: In this prospective, observational, cohort study, 62 patients (62 eyes) with Mac-Tel2 and 130 healthy controls (130 eyes) underwent a complete ophthalmological examination, spectral-domain optical coherence tomography (SD-OCT) imaging, and axial length measurements. Patients in the study group also underwent color fundus photography, fundus autofluorescence, and fluorescein angiography. En face SD-OCT imaging was used to assess abnormalities involving the photoreceptor inner segment/outer segment/ellipsoid zone (IS/OS/EZ). RESULTS: After adjusting for age and axial length, the authors found that eyes with MacTel2 had a mean CT measurement that was greater than control eyes (P = .007). There was a negative correlation between the visual acuity and the area of IS/OS/EZ damage (P = .009), but no statistically significant correlation was seen between CT and the area of IS/OS/EZ damage. CONCLUSION: Eyes with MacTel2 were found to have thicker CT measurements than control eyes. While the extent of IS/OS/EZ disruption correlated with the loss of visual acuity, this damage did not correlate with CT measurements.

PURPOSE: To evaluate the changes of vascular endothelial growth factor (VEGF) plasma levels after intravitreal injections of aflibercept or ranibizumab in patients with exudative age-related macular degeneration (AMD). METHODS: Thirty-eight patients with exudative AMD were included in this randomised, prospective study. Nineteen patients were randomised to treatment with intravitreal aflibercept (2.0 mg) and 19 to intravitreal ranibizumab (0.5 mg). The concentration of VEGF was measured by ELISA just before the injection, after 7 days and 1 month. Twenty-two age- and sex-matched healthy patients without chorioretinal diseases served as control. RESULTS: The median baseline plasma VEGF concentration was 61.0 pg/ml in the control group, 43.0 pg/ml in the aflibercept group and 59.0 pg/ml in the ranibizumab group (p=0.127). Seven days after intravitreal injection of aflibercept plasma levels were significantly reduced to values below the minimum detectable dose (MDD) in 17 of 19 patients (89.5%) resulting in a median VEGF concentration of <9 pg/ml (p<0.001). The reduction persisted throughout 1 month with values below the MDD in 5 of 19 patients (26.3%) and a median measurement of 17.0 pg/ml (p<0.001). In patients treated with ranibizumab no significant effects could be observed with a baseline VEGF of 59.0 pg/ml, 54.0 pg/ml at 7 days (p=0.776) and 58.5 pg/ml at 4 weeks of follow-up (p=0.670). CONCLUSION: After intravitreal aflibercept injection, the systemic VEGF levels were significantly reduced throughout the observational period of 4 weeks. No significant systemic effects of intravitreal ranibizumab on plasma VEGF were observed.

BACKGROUND AND OBJECTIVE: To evaluate subfoveal choroidal thickness (CT) in healthy eyes using spectral-domain optical coherence tomography (SD-OCT) and provide correlations between age and axial length. PATIENTS AND METHODS: Enhanced depth SD-OCT imaging was performed with Cirrus (Carl Zeiss Meditec, Dublin, CA) and Spectralis (Heidelberg Engineering, Heidelberg, Germany) instruments. CT was measured from the outer limit of the retinal pigment epithelium to the inner surface of the sclera. RESULTS: The study enrolled 155 patients, with at least 20 in each decade between 22 and 89 years old. Mean axial length was 23.6 mm. Mean Heidelberg subfoveal CT was 286 microm. The correlation between Heidelberg and Zeiss subfoveal CT measurements was strong (r = .978) and significant (P < .001). Mean subfoveal CT was 7.7 microm thinner by Heidelberg versus Cirrus (P < .001). Multiple linear regression analysis revealed that age (P < .001), axial length (P = .001), and sex (P = .025) were significantly related to Heidelberg subfoveal CT. CONCLUSION: There is a strong negative correlation between CT and age (P <.001), with a 25 microm decrease in CT for each decade of life. Increasing axial length demonstrated a negative correlation with CT, decreasing 24.9 microm for each mm of axial length. Future studies of CT measurements can be performed on either instrument and must account for axial length, age, and sex to make appropriate conclusions.

Neovascular age-related macular degeneration (NVAMD) is one of the leading causes of blindness. Over the last decade, the treatment of NVAMD has been revolutionized by the development of intravitreal anti-vascular endothelial growth factor (VEGF) therapies. Several anti-VEGF medications are used for the treatment of NVAMD. The safety and tolerability of these medications deserve review given the high prevalence of NVAMD and the significant utilization of these medications. Numerous large randomized clinical trials have not shown any definitive differential safety relative to ocular or systemic safety of these medications. Intravitreal anti-VEGF therapy does appear to impact systemic VEGF levels, but the implications of these changes remain unclear. One unique safety concern relates drug compounding and the potential risks of contamination, specifically for bevacizumab. Continued surveillance for systemic safety concerns, particularly for rare events, is merited. Overall, these medications are well tolerated and effective in the treatment of NVAMD.

PURPOSE: We reported the clinical and echographic features of colobomas, prevalence of retinal detachment, and associated visual acuity in these patients. METHODS: The study is a nonrandomized consecutive case series of 140 colobomatous eyes in 98 patients (age range, 0-83 years). Coloboma depth, width, volume, and relative coloboma excavation (coloboma depth/axial length) were measured using standardized echographic images. The presence of structural and other ocular abnormalities was noted. The clinical and echographic findings present were correlated with visual acuity of the patient. In addition, these features were correlated with the presence or absence of retinal detachment. RESULTS: Increased relative coloboma excavation was significantly associated with an increased risk of retinal detachment. A relative coloboma excavation (ratio of coloboma depth to axial length) greater than 0.15 was associated with an increased risk of retinal detachment (52%), compared to those with a relative coloboma excavation less than 0.15 (23%, P = 0.014). The presence of any structural abnormality and the presence of a retrobulbar cyst were associated with increased risk of retinal detachment and severe visual impairment (worse than 20/200). Increased coloboma depth, width, volume, and relative coloboma excavation were not associated with increased risk of severe visual impairment. CONCLUSIONS: Clinical and echographic features of colobomas may be used in predicting the risk of retinal detachment. Measuring relative coloboma excavation upon presentation may alter follow-up and assist in the diagnosis of retinal detachment.