Yusuke Ichiyama

Optical Coherence Tomography Angiography in a Patient with Optic Atrophy After Non-arteritic Anterior Ischaemic Optic Neuropathy

ABSTRACT A 75-year-old female noticed a lower visual field (VF) defect in the right eye. A diagnosis of non-arteritic anterior ischaemic optic neuropathy (NAION) was made. The lower VF defect in the right eye did not change after onset. Optical coherence tomography (OCT) angiograms on the disc and the macula showed decreased retinal perfusion in the upper retina of the right eye. Retinal nerve fibre layer loss and ganglion cell complex loss in the upper retina were also seen in the right eye. OCT angiography could non-invasively detect the decrease of the retinal perfusion due to NAION.

Capillary Dropout at the Retinal Nerve Fiber Layer Defect in Glaucoma: An Optical Coherence Tomography Angiography Study

Purpose: To investigate the microvasculature changes of retinal nerve fiber layer (RNFL) defects in glaucoma. Design: The study design is a case report. Patients and Methods: Four glaucomatous eyes were included in this observational cross-sectional study. The microvasculature changes of RNFL defects were examined using optical coherence tomography (OCT) angiography. Results: Three eyes had apparent wedge-shaped capillary dropout on OCT angiography. In the fourth eye, detection of wedge-shaped capillary loss was difficult because of overall capillary drop out due to advanced glaucoma. Capillary dropout detection by OCT angiography was correlated with visual field loss and RNFL defect detection by regular OCT. Compared with regular OCT used to obtain retinal thickness maps, OCT angiography is often better at visualizing the borders of lesions in the RNFL. Conclusions: OCT angiography can detect capillary dropout in RNFL defects in glaucomatous eyes, and therefore could be a useful glaucoma examination tool.

Optical Coherence Tomography Angiography of Retinal Perfusion in Chiasmal Compression

BACKGROUND AND OBJECTIVE To evaluate the retinal perfusion in patients with chiasmal compression using optical coherence tomography angiography (OCTA). PATIENTS AND METHODS Retinal perfusion was evaluated using OCT angiograms in eight eyes of four patients with visual field (VF) defects due to chiasmal compression treated by tumor resection. The retinal perfusion in the area corresponding to the quadrants of the VF defects was investigated in each image. The vessel density was defined as the percentage area occupied by the vessels in the image. RESULTS The decreased peripapillary retinal perfusion correlated with the quadrants of the VF defects on OCT angiograms in all patients. The binarized vessel density decreased, corresponding to the degree of VF defects in all patients. CONCLUSIONS A decrease in peripapillary retinal perfusion correlates with the quadrants of the VF defects due to chiasmal compression. This decrease can be noninvasively measured by OCTA. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:724-729.].

PHOTORECEPTOR OUTER SEGMENT LENGTH AND OUTER FOVEAL THICKNESS AS FACTORS ASSOCIATED WITH VISUAL OUTCOME AFTER VITRECTOMY FOR VITREOMACULAR TRACTION SYNDROME.

Purpose: To investigate the predictive factors for postoperative best-corrected visual acuity (BCVA) in patients with vitreomacular traction syndrome treated with vitrectomy. Methods: The records of 21 patients with 21 eyes that underwent vitrectomy for vitreomacular traction syndrome and followed for at least 12 months were retrospectively reviewed. The BCVA and spectral domain optical coherence tomography findings were investigated preoperatively and at 1, 3, 6, and 12 months postoperatively. Axial length was measured preoperatively. The correlations between 12-month postoperative BCVA and preoperative parameters, including BCVA, age, axial length, central foveal thickness, outer foveal thickness, and photoreceptor outer segment length, were evaluated. Results: Twelve-month postoperative BCVA was significantly negatively correlated with preoperative outer foveal thickness and photoreceptor outer segment length (outer foveal thickness: P = 0.029, r = −0.501; photoreceptor outer segment length: P = 0.022, r = −0.523, respectively) but not correlated with age, axial length, preoperative BCVA, and preoperative central foveal thickness (age: P = 0.346, r = 0.216; axial length: P = 0.333, r = 0.242; BCVA: P = 0.202, r = 0.290; central foveal thickness: P = 0.065, r = −0.410, respectively). Conclusion: Preoperative outer foveal thickness and photoreceptor outer segment length could be good predictive factors of postoperative BCVA in patients with vitreomacular traction syndrome.

Optical Coherence Tomography Angiography Reveals Blood Flow In Choroidal Neovascular Membrane In Remission Phase Of Neovascular Age-related Macular Degeneration

Purpose: The aim of the study was to investigate blood flow in choroidal neovascular membrane in remission phase of neovascular age-related macular degeneration using optical coherence tomography (OCT) angiography. Methods: OCT angiography was obtained in eyes with remission phase of neovascular age-related macular degeneration after treatments, defined as no exudative change (such as macular edema, subretinal fluid, and subretinal hemorrhage) observed in eyes without any treatment for neovascular age-related macular degeneration within the previous 6 months. Irregular blood flows shown in the segmentation of outer retina detected by OCT angiography were considered as blood flows in choroidal neovascular membrane. The vascular area and vessel density were obtained from OCT angiography images. Results: Twenty eyes of 20 patients were included in this analysis. The blood flows in choroidal neovascular membrane were observed in all eyes (100%) using OCT angiography. The mean vascular area was 3.81 ± 3.41 mm2 and the mean vessel density of lesion was 28.9 ± 8.2%. The vessel density was significantly correlated with best-corrected visual acuity and duration of remission (best-corrected visual acuity: P = 0.008, r = −0.576; duration of remission: P = 0.017, r = −0.525, respectively). Conclusion: Optical coherence tomography angiography revealed that blood flows in choroidal neovascular membrane remained in eyes with clinically inactive neovascular age-related macular degeneration.

Anterior chamber paracentesis might prevent sustained intraocular pressure elevation after intravitreal injections of ranibizumab for age-related macular degeneration.

Background/Aims: To evaluate the efficacy of anterior chamber paracentesis for preventing sustained intraocular pressure (IOP) elevation after intravitreal ranibizumab (IVR) injections for age-related macular degeneration (AMD). Methods: The medical records for all cases of exudative AMD treated with IVR injections and followed monthly for 12 months or longer were reviewed retrospectively. Anterior chamber paracentesis was performed just before IVR injections. A sustained IOP elevation was defined as 22 mm Hg or higher during 2 consecutive visits with an increase exceeding 6 mm Hg from baseline. Results: One hundred and eleven eyes met the inclusion criteria, and none of these eyes had a sustained IOP elevation. Conclusions: Anterior chamber paracentesis before IVR injections may prevent sustained IOP elevations.

The possible mechanisms of subretinal fluid resolution after vitrectomy

To the Editor: We wish to thank Drs. Kaya and Aksoy for their interest and questions regarding our report on the effectiveness of vitrectomy in diffuse diabetic macular edema [1]. In our study, we found that vitrectomy was effective for the treatment of diffuse diabetic macular edema, particularly in eyes with subretinal fluid (SRF). As the commenters indicated, SRF may be associated with impairment of the outer blood retinal barrier or of pump function of retinal pigment epithelium (RPE). However, it is still unknown why dysfunction of RPE had developed in these patients with diabetic mellitus, so we cannot provide a robust answer as to why vitrectomy was effective for the resolution of SRF. Several possible reasons for this could be suggested, as follows: First, vitrectomy might improve the oxygenation of ischemic RPE and might increase the ability to pump fluid. Previous studies have demonstrated the decreased ability of RPE to pump fluid in hypoxic settings [2, 3]. In patients with diabetic mellitus, RPE might be occurring in a hypoxic setting, although choroidal blood flow is high. Second, induction of posterior vitreous detachment (PVD) might improve the function of the outer retinal barrier. Previous reports demonstrated that vitreomacular adhesion and associated traction was strongly associated with the progression of neovascular age-related macular degeneration [4], and vitrectomy could be a suitable treatment [5]. These results suggested that surgical induction of PVD could have positive influence on the function of the outer retinal barrier. Finally, vitrectomy might increase external stimuli to RPE, resulting in enhanced RPE function, as Drs. Kaya and Aksoy suggested. However, all possible reasons described above have insufficient evidence for their establishment. Further research is needed to reveal the pathogenesis of diabetic macular edema, including SRF and the mechanisms of SRF resolution after vitrectomy. We really hope that our report can be of assistance in this work.

Contents Vol. 52, 2014

175 SIRCOVA-OFTARED-RIG Joined Congress Abstracts Valencia (Spain), November 7–8, 2014 (online only) 239 Acknowledgement to Referees