Structural Changes of the Macula on Optical Coherence Tomography after Vitrectomy for Proliferative Diabetic Retinopathy.

PURPOSE: This study aimed to evaluate the relationship between macular structural changes and visual prognosis after pars plana vitrectomy (PPV) for proliferative diabetic retinopathy. METHODS: The study included 60 eyes that had undergone PPV. Macular optical coherence tomography (OCT) findings were classified into 5 groups preoperatively and 10 groups postoperatively. Best-corrected visual acuity (BCVA) were analyzed according to pre- and postoperative OCT. RESULTS: From the preoperative OCT, normal fovea with/without traction, normal fovea with preretinal hemorrhage, and tractional retinal detachment involving fovea showed an increase in BCVA after PPV (all p < 0.05). Normal fovea, epiretinal membrane and macular thickening were common after surgery. Normal fovea, epiretinal membrane and edema outside of the fovea showed good visual prognosis (BCVA >20/50). Subfoveal fibrosis, macular hole, loss of foveal depression, and serous foveal detachment showed poor visual prognosis (BCVA <20/100). CONCLUSION: Macular structural changes were various after PPV, and visual prognosis correlated with these changes.

Short-term Analysis of the Residual Volume of an Eye Drop Following 23-Gauge Microincision Vitrectomy Surgery.

PURPOSE: To evaluate the change of residual volume of eye drop after instillation in patients with 23-gauge microincision vitrectomy surgery (MIVS). METHODS: Patient who were treated 23-gauge MIVS from November 2014 to July 2015 were included. The residual volume was defined as the amount of remnant eye drop in patient's eyes after instillation, calculated as the difference between instillation volume and spilled volume of eye drop. Calculation of residual volume of eye drop was performed one day before surgery, and daily from postoperative day 1 to day 5. RESULTS: Forty consecutive patients were included. The residual volume of eye drop decreased from 30.3 ± 1.4 µL at baseline to 13.0 ± 1.5 µL at day 1, 18.3 ± 1.6 µL at day 2, 24.7 ± 1.5 µL at day 3, and 27.9 ± 1.4 µL in day 4, postoperatively (p < 0.001, respectively). The volume at postoperative day 5 was 29.4 ± 1.3 µL, but it was not different from the volume at baseline (p = 0.105). The change of residual volume was significantly correlated with postoperative chemosis (r = 0.672, p < 0.001) and effected by the number of quadrant with postoperative chemosis (p < 0.05). CONCLUSIONS: This study shows that postoperative residual volume of eye drop after instillation decreased until postoperative day 4, and postoperative chemosis affects the change of residual volume. Thus, checking proper use of eye drops and teaching about instillation technique by physician is necessary for patients with 23-gauge MIVS.

Does Intravitreal Dexamethasone Implant Fragmentation Affect Clinical Outcomes in Macular Edema from Branch Retinal Vein Occlusion?

PURPOSE: The aim of this study was to evaluate the effect of intravitreal dexamethasone implant fragmentation on clinical outcomes in branch retinal vein occlusion (BRVO)-induced macular edema (ME). METHODS: All consecutive patients receiving an intravitreal dexamethasone implant for BRVO-induced ME were divided into two groups depending on whether the implant was intact or had fragmented into two or more pieces on postoperative day 1. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), and central subfield thickness (CST) on spectral-domain optical coherence tomography were measured for 6 months. RESULTS: Among 68 patients, the implant was fragmented in 6 (8.8%) and intact in 62 (91.2%) eyes. The two groups did not differ in BCVA and CST at any time point (all p > 0.05). There was no difference in the ME recurrence rate, frequency of IOP elevation, and cataract progression between the two groups (all p > 0.05). CONCLUSION: Fragmentation seemed not to influence clinical outcomes of intravitreal dexamethasone implantation during 6 months or to alter the frequency of adverse events.

Recurrence of macular edema in eyes with branch retinal vein occlusion changes the diameter of unaffected retinal vessels.

PURPOSE: To measure unaffected retinal vessel diameter in eyes with macular edema (ME) secondary to branch retinal vein occlusion (BRVO) after intravitreal injection with bevacizumab (IVB). METHODS: Patients with BRVO-induced ME who responded to IVB were assessed at baseline and 1, 3, and 6 months. In both eyes, the diameters of the largest arteriole and venule in all quadrants (except occlusion quadrant) were measured by using a computer-assisted method. The same vessels chosen at baseline were measured at each follow-up examination. RESULTS: Forty-two eyes were participated. At baseline, venular diameters of unaffected quadrants in eyes with BRVO were larger than the venules in the corresponding quadrant of the fellow eyes (p < 0.05, respectively). The venular diameters in all quadrants of the affected eyes decreased significantly relative to baseline after IVB (p < 0.05 respectively). Twenty-two eyes (52.4 %) developed recurrent ME. On recurrence at 3 (n = 15, 35.7 %) or 6 months (n = 7, 16.7 %), the unaffected venular diameters increased significantly (p < 0.05 respectively). These diameters again decreased significantly after a second IVB (p < 0.05 respectively). CONCLUSION: Unaffected retinal venular diameters associate with the course of BRVO with ME. This may help elucidate the pathological mechanism underlying BRVO.

One-year follow-up of macular ganglion cell layer and peripapillary retinal nerve fibre layer thickness changes after panretinal photocoagulation.

BACKGROUND/AIMS: To assess the changes of ganglion cell-inner plexiform layer (GCIPL) thickness, retinal nerve fibre layer (RNFL) thickness, and central subfield thickness (CST) after panretinal photocoagulation (PRP) in diabetic retinopathy for 1 year. METHODS: This prospective, interventional case series study examined 35 patients (35 eyes) undergoing PRP, who were diagnosed with severe non-proliferative diabetic retinopathy to non-high-risk proliferative diabetic retinopathy without macular oedema. Macular GCIPL thickness, CST, and peripapillary RNFL thickness were measured by spectral-domain optical coherence tomography at baseline, and then at 1, 3, 6, 9 and 12 months after PRP. RESULTS: Macular GCIPL and peripapillary RNFL (average and all sections) thickness at each follow-up increased significantly from the baseline (p<0.001, respectively). The average, superior and inferior RNFL thickness at 12 months after PRP decreased significantly compared to the 1-month post-PRP (p=0.007, p=0.028 and p=0.025). The average GCIPL and temporal RNFL thickness showed a significant correlation at each follow-up (p<0.001, respectively). CST at each follow-up increased significantly from the baseline (p<0.001, respectively). CONCLUSIONS: The macular GCIPL and peripapillary RNFL thickness increased throughout the 1-year post-PRP. Furthermore, the macular GCIPL and temporal RNFL thickness showed a significant correlation throughout the 1 year of follow-up.