Neurodegenerative changes of retina in Parkinson disease

In Parkinson’s disease (PD), some structural changes in the retina have been shown using optical coherence tomography (OCT). Among them most attractive are atrophic changes in retinal nerve fi ber layer (RNFL). However, diagnostic signifi cance of the OCT method in PD remains debatable. Objective: to investigate a thickness of RNFL in Parkinson’s disease patients and to determine the signifi cance of the OCT method in the PD diagnostics. Materials and methods. In PD patients (n = 24) and in a control group (n = 20) OCT was used to study the thickness of RNFL — average, in quadrants and in 10 sectors. Results. In patients with PD thinning of RNFL in the inferior quadrant was revealed (p = 0.009). The sensitivity and specifi city of the method were 56% and 82%, respectively. The thickness of RNFL was not associated with parkinsonian symptoms asymmetry, duration and severity of the disease. In the control group and in PD patients, there was a relationship between the RNFL thickness and age. Conclusion. PD is characterized by atrophic changes in the retina in the form of thinning of RNFL in the inferior quadrant, which confi rms the systemic nature of neurodegenerative pathology in this disease going beyond the substantia nigra and brain tissue. At the same time, the thickness of RNFL showed limited diagnostic value for detecting PD cases.

Relationship of Peripapillary Retinal Perfusion with Peripapillary Retinal Nerve Fiber Layer Thickness in Diabetes Mellitus Patients without Diabetic Retinopathy

Introduction: Impaired blood flow is an early sign of retinal dysfunction in diabetes. Impaired blood flow of the radial peripapillary capillaries can affect the Retinal Nerve Fiber Layer (RNFL) or ganglion cell function. Methods: This was an analytic cross-sectional study in February-April 2019 at Bandung. The subjects of this study were 41 people (79 eyes) divided into two groups, group A (healthy subjects) 19 people (37 eyes) and group B (DM type 2 without diabetic retinopathy) 22 people (42 eyes). Peripapillary retinal perfusion was assesed using OCT Angiography and RNFL thickness was assesed using OCT. Pearson or Spearman correlation statistics test was used to analyze the result. P value ≤0.05 was consiedered significant. Results: There was a decrease in peripapillary retinal perfusion density in the inferior quadrant (P = 0.003) and flux index throughout the peripapillary retinal quadrant (P = 0.0001) but an increase in RNFL thickness in the peripapillary temporal quadrant (P = 0.012) compared to control grup. Positive correlation was found between peripapillary retinal perfusion density and RNFL thickness globally (r = 0.480, P = 0.001), superior quadrant (r = 0.436, P = 0.004), and inferior quadrant (r = 0.608, P = 0.000). A positive correlation was also found between the peripapillary flux and RNFL thickness globally (r = 0.517, P = 0.000), superior quadrant (r = 0.630, P = 0.000), and inferior quadrant (r = 0.519, P = 0.000). Conclusions: There was a relationship between peripapillary retinal perfusion and RNFL thickness in DM patients without diabetic retinopathy. Keywords: Peripapillary perfusion, RNFL thickness, Diabetes.

Study of retinal nerve fiber layer thickness in chronic kidney disease patients

To compare the RNFL thickness between CKD patients and age matched healthy controls and to correlate RNFL thickness with duration of CKD. RNFL thickness was also assessed in CKD patients with and without haemodialysis.: One hundred and fifty eyes were included in the study and were labeled as group A. Equal number of age matched controls were included in group B. RNFL thickness was measured using optical coherence tomography for optic nerve head (ONH) scan.Mean of average RNFL thickness was studied to be thinner in group A in comparison to group B. Statistically significant thinning was also noted in superior and inferior quadrant of group A. Increase in average RNFL thickness and increase in superior and temporal quadrant RNFL thickness was noted in HD group as compared to non- HD group. A negative correlation was noted between RNFL thickness and duration of CKD. : This study concluded that RNFL thickness was found to be thinner in CKD patients as compared to healthy individuals. However RNFL thickness was found to be thicker in HD group as compared to non- HD group.

Peripapillary vessel density measurement of quadrant and clock-hour sectors in primary angle closure glaucoma using optical coherence tomography angiography

Background The purpose of this study was to investigate diagnostic ability of peripapillary vessel density of primary angle closure glaucoma (PACG) eyes in quadrant and clock-hour sectors by optical coherence tomography angiography (OCTA). Methods This was a cross-sectional study on forty-one PACG patients (41eyes) and twenty-seven healthy subjects (27 eyes). All subjects underwent OCTA (DRI OCT Triton; Topcon Corporation, Tokyo, Japan) and peripapillary retinal nerve fiber layer (RNFL) thickness imaging with swept-source optical coherence tomography (OCT). The peripapillary vessel density of quadrant and clock-hour sectors was quantified by imageJ software. The diagnostic capability of OCTA and OCT parameters was evaluated by the areas under the receiver operating characteristics curves (AUCs). Pearson correlation analysis or Spearman correlation test was used to evaluate the correlation between vessel density parameters and related factors. Results Compared with the control group, the peripapillary vessel density of glaucomatous group was lower to different degrees in the four quadrants and each clock-hour sectors, and vessel density reduced most at 7 o’clock. The difference between the diagnostic ability of peripapillary vessel density and peripapillary RNFL thickness was not statistically significant, except 4 o’clock and inferior quadrant. The inferior quadrant peripapillary vessel density had the best diagnostic value (AUC0.969), followed by the 7 o’clock vessel density (AUC0.964), average vessel density (AUC0.939) and the 7 o’clock RNFL thickness (AUC0.919). The average peripapillary vessel density was correlated with average RNFL and visual field (VF) mean deviation (P < 0.001). Conclusions In PACG, the diagnostic ability of the peripapillary vessel density is equivalent to the peripapillary RNFL thickness. Understanding spatial characteristics of the peripapillary vessel density in PACG may be helpful for clinical diagnosis and monitoring the progress of diseases.

Peripapillary and Macular Choroidal Vascularity Index in Eyes with Fuchs’ Uveitis

Background To investigate the choroidal vascularity alterations of macula and peripapillary area in eyes with unilateral Fuchs uveitis (FU). Methods This study included 18 eyes with unilateral FU and 18 healthy fellow eyes. The choroidal vascularity index (CVI) was analyzed and the results were compared between eyes with FU and healthy fellow eyes (control group). Results The mean subfoveal (s)CVI (%) value was significantly lower in the FU group as compared with the control group:60.92 ± 2.63 vs. 64.01 ± 2.54,respectively (p = 0.001). The mean pCVI (%) values of superior and inferior quadrant were significantly lower in the Fuchs group as compared with the control group:58.87 ± 4.48 vs. 61.98 ± 3.32, respectively, in superior quadrant (p = 0.035); and 57.29 ± 6.65 vs. 61.44 ± 4.76, respectively, in inferior quadrant (p = 0.014). Conclusion The chronic continuous inflammation in FU causes inflammation-mediated thinning in the vascular area of the subfoveal and peripapillary choroid. The changes in the peripapillary region are remarkable in terms of the further glaucoma risk of these eyes.

The Role of Optical Coherence Tomography Angiography in Moderate and Advanced Primary Open-Angle Glaucoma

Purpose: To evaluate the relationship between structure and function in moderate and advanced primary open-angle glaucoma (POAG) and to determine the accuracy of structure and vasculature for discriminating moderate from advanced POAG.Methods: In this cross-sectional study 25 eyes with moderate and 40 eyes with advanced POAG were enrolled. All eyes underwent measurement of the thickness of circumpapillary retinal nerve fiber layer (cpRNFL) and macular ganglion cell complex (GCC), and optical coherence tomography angiography (OCTA) of the optic nerve head (ONH) and macula. Visual field (VF) was evaluated by Swedish interactive threshold algorithm and 24-2 and 10-2 patterns. The correlation between structure and vasculature and the mean deviation (MD) of the VFs was evaluated by a partial correlation coefficient. The area under the receiver operating characteristic curve (AUC) was applied for assessing the power of variables for discrimination moderate from advanced POAG.Results: Superior cpRNFL, superior GCC, whole image vessel density (wiVD) of the ONH area, and vessel density in inferior quadrant of perifovea had the strongest correlation with the mean deviation (MD) of the VF 24-2 (r= .351, .558, .649 and .397; p< .05). The greatest AUCs belonged to inferior cpRNFL (.789), superior GCC (.818), vessel density of the inferior hemifield of ONH area (.886), and vessel density in inferior quadrant of perifovea (.833) without statistically significant difference in pairwise comparison.Conclusion: Vasculature has a stronger correlation than the structure with MD in moderate and advanced POAG and is as accurate as structure in discrimination moderate from advanced POAG.

Retinal nerve fibre layer thickness measurements in childhood glaucoma: the role of scanning laser polarimetry and optical coherence tomography

Purpose A central diagnostic tool in adult glaucoma is the peripapillary retinal nerve fibre layer (pRNFL) thickness. It can be assessed by scanning laser polarimetry (SLP) or optical coherence tomography (OCT). However, studies investigating the relevance of pRNFL measurements in children are rare. This study aims to compare the glaucoma diagnosing ability of SLP and OCT pRNFL thickness measurements in a paediatric population. Methods This retrospective study included 105 children (glaucoma: 22 (21.0%); healthy glaucoma suspects: 83 (79.0%)) aged 4–18 years, examined with SLP (GDxPro/ECC, Carl Zeiss Meditec) and spectral-domain OCT (SPECTRALIS®, Heidelberg Engineering). The thickness of pRNFL sectors was compared between diseased and healthy participants. Areas under the receiver-operating characteristic curves (AUC) and logistic regression results were used to compare the glaucoma discriminative capacity between SLP and OCT measurements. Results Using OCT, pRNFL thickness was decreased in the superior, nasal, and inferior quadrants of glaucoma patients compared to healthy controls (P < 0.001, each). With SLP, such a difference was only observed in the inferior quadrant (P = 0.011). A correlation between glaucoma diagnosis and OCT-measured pRNFL thickness was found in all quadrants (P < 0.001) other than the temporal. With SLP, a correlation was found for the total average thickness (P = 0.037) and inferior quadrant (P = 0.0019). Finally, the AUCs of OCT measurements were markedly higher than those of SLP (e.g., inferior quadrant: OCT 0.83, SLP 0.68). Conclusion pRNFL thickness measurements using both OCT and SLP, correlate notably with the presence of glaucoma. In general, the diagnostic performance of pRNFL thickness measurements seems higher for OCT than for SLP. Thus, pRNFL thickness measurements could provide important information, complementing conventional clinical and functional parameters in the diagnostic process of paediatric glaucoma.

Does a Relationship Exist Between Posterior Vitreous Detachment, Macular Thickness and Foveal Avascular Zone Dimensions in Myopic Eyes?

Background: The posterior vitreous detachment (PVD) is a separation of the posterior vitreous cortex from the internal limiting membrane of the retina. The PVD induces several potentially serious pathologic events at the vitreoretinal interface. The aim of the study is to determine if relationships exist between PVD, macular thickness (MT) and the foveal avascular zone (FAZ) in myopic eyes. Methods: This is a retrospective case study of 63 myopic subjects who underwent comprehensive eye examination including the optical coherence tomography angiography (OCTA) between January 1 and Jun 30, 2019. The spherical equivalent (SE) was calculated using the manifest refraction. The myopia grouping was based on a severity scale, namely mild, moderate, high and very high using standard refractive error classifications. The PVD classification was based on optical coherence tomography (OCT) images. The status of the PVD and MT were evaluated with Macular Cube 200 × 200 images and the FAZ was imaged with an OCTA, Angioplex. The MT and FAZ dimensions were calculated using a custom algorithm. Results: A total of 114 myopic eyes subjects had median (range) age of 26.00 (22.00 - 28.00) years. Of this cohort, females comprised 62.3 % of the dataset, and the right eyes were 50.00 %. In this population, 10 eyes had no PVD in any quadrant, and 73 eyes had incomplete PVD in all four quadrants. The inferior quadrant had the maximum number of PVD cases and the nasal quadrant had the least number of cases. High myopic eyes exhibited significantly increased low foveal volume (p = 0.000). The inferior part of para- and perimacular area showed a significant thinning in very high myopic eyes (p = <0.05). A statistically significant alteration of FAZ circularity index found in very high myopic eyes (p = 0.002). Conclusion: In high and very high myopic eyes, an increasing trend of partial PVD is seen. The most commonly involved location was the inferior quadrant. A significant alteration in foveal volume and circularity index of the FAZ is seen in high and very high myopic eyes.

Iris cyst after femtosecond laser-assisted cataract surgery: a case report

Background Secondary iris cysts are uncommon complication after cataract surgery. The reports of an iris cyst after conventional phacoemulsification surgery are scanty, let alone the iris cyst following femtosecond laser-assisted cataract surgery (FLACS). We herein report an unusual case of an iris cyst after an uneventful FLACS. Case presentation A 64-year-old man who was healthy underwent FLACS for a moderate cataract of his left eye. Shortly after surgery, he achieved 20/20 vision, but anterior bowing of temporal iris was noted on postoperative day 9 with a retro-pupillary iris cyst at temporal-inferior quadrant found after pupil dilatation. The cyst was confirmed by ultrasound bio-microscopy afterward. Four weeks later, argon laser cystotomy was performed, and the cyst disappeared 3 days later. The patient’s vision remained stable thereafter. Conclusion Although rare, secondary iris cyst may be one of the complications after FLACS. Argon laser cystotomy is effective in the management of post-FLACS iris cyst.

Correlation between retinal nerve fiber layer thickness and IOP variation in glaucoma suspects and patients with primary open-angle glaucoma

Purpose: To analyze the relationship between retinal nerve fiber layer thickness (RNFLT) and intraocular pressure (IOP) variation in glaucoma suspects (GS) and patients with primary open-angle glaucoma (POAG). Methods: Thirty-one GS and 34 POAG patients underwent ophthalmologic examination and 24-h IOP measurements. GS had IOPs ranging from 19 to 24 mmHg and/or suspicious appearance of the optic nerve. POAG patients had reproducible abnormal visual fields. We only included patients who presented with short-term IOP fluctuation >6 mm Hg (∆IOP). Only one eye per patient was included through a randomized process. Peripapillary RNFLT was assessed by spectral-domain optical coherence tomography. We correlated RNFLT with IOP parameters. Results: Mean IOP was similar between GS and POAG groups (15.6 ± 3.47 vs 15.6 ± 2.83 mmHg, p = 0.90) as was IOP peak at 6 AM (21.7 ± 3.85 vs 21.3 ± 3.80 mmHg, p = 0.68). Statistically significant negative correlations were found in POAG group between IOP at 6 AM and RNFLT in global ( rs = −0.543; p < 0.001), inferior ( rs = −0.540; p < 0.001), superior ( rs = −0.405; p = 0.009), and nasal quadrants ( rs = −0.561; p < 0.001). Negative correlations were also found between ∆IOP and RNFLT in global ( rs = −0.591; p < 0.001), and all other sectors ( p < 0.05). In GS IOP at 6 AM correlated only with inferior quadrant ( rs = −0.307; p = 0.047). Conclusion: IOP at 6 AM and ∆IOP had negative correlations with RNFLT quadrants in POAG. In GS this correlation occurred between IOP at 6 AM and inferior quadrant. These findings may indicate potential risk factors for glaucoma progression.