Automated Detection of Retinal Nerve Fiber Layer by Texture-Based Analysis for Glaucoma Evaluation.

OBJECTIVES: The retinal nerve fiber layer (RNFL) is a site of glaucomatous optic neuropathy whose early changes need to be detected because glaucoma is one of the most common causes of blindness. This paper proposes an automated RNFL detection method based on the texture feature by forming a co-occurrence matrix and a backpropagation neural network as the classifier. METHODS: We propose two texture features, namely, correlation and autocorrelation based on a co-occurrence matrix. Those features are selected by using a correlation feature selection method. Then the backpropagation neural network is applied as the classifier to implement RNFL detection in a retinal fundus image. RESULTS: We used 40 retinal fundus images as testing data and 160 sub-images (80 showing a normal RNFL and 80 showing RNFL loss) as training data to evaluate the performance of our proposed method. Overall, this work achieved an accuracy of 94.52%. CONCLUSIONS: Our results demonstrated that the proposed method achieved a high accuracy, which indicates good performance.

Retinal Arteriolar Narrowing in Young Adults With Glaucomatous Optic Disc.

PURPOSE: Glaucomatous optic disc (GOD) might represent various subclinical processes. However, whether the presence of GOD is related to vascular processes is less clear. This study aimed to assess the retinal vessel diameter, as surrogate markers of vascular regulation, in healthy young adults with GOD compared with normal. MATERIALS AND METHODS: This was a clinic-based case-control study of 54 participants, aged between 18 and 30 years. We included patients with GOD (confirmed with slit-lamp and optical coherence tomography examination having cup-to-disc ratio ≥0.5), intraocular pressure ≤21 mm Hg, no history of hypertension, cardiovascular and kidney disease, anemia, diabetes mellitus, and spherical correction of ≤-1.5 D. Controls were healthy subjects with similar criteria but no sign of GOD. Retinal vessel diameters were measured using semiautomated program [Singapore I Vessel Assessment (SIVA) version 4.0] and expressed as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent. RESULTS: The mean CRAE was significantly narrower in patients with GOD than controls (110.6±12.16 vs. 118.6±12.17; P=0.019). Central retinal venular equivalent was not significantly different. A CRAE narrower than 107.1 µm was significantly associated with GOD (odds ratio, 8.59; 95% confidence interval, 1.68-43.9; P<0.001) compared with controls. CONCLUSIONS: Retinal arterioles were narrower in young adults with GOD compared with normal, suggesting that the presence of GOD might be associated with subclinical changes in retinal vascularization even in the absence of increased intraocular pressure. However, the clinical significance of these findings deserves further studies.

Density and morphology of corneal endothelial cell after phacoemulsification using Ringer lactate versus balanced salt solution as irrigating solutions / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the difference in corneal endothelial cell density and morphology after phacoemulsification using Ringer lactate ( RL ) and balanced salt solution ( BSS) irrigating solutions.?METHODS: The prospective randomized controlled trial study was conducted between February 2017 and April 2017 in Dr. YAP Eye Hospital, Yogyakarta, Indonesia. There were a total of 52 subjects ( 52 eyes ) who were senile cataract patients further grouped into two, 26 patients undergoing the phacoemulsification procedure using RL irrigating solution and the other 26 patients with BSS irrigating solution, both conducted by one operator. On the 1, 7, and 28d post operative, an evaluation was done to measure the density and corneal endothelial cell morphology, as well as the variable of inflammation in the two groups.? RESULTS: Fifty - two eyes had undergone phacoemulsification with posterior intraocular lens implantation. Both groups were evaluated for the endothelial cell reduction and corneal endothelial cell morphology change, along with post - operative inflammation. On the 28d post-operative, endothelial cell reduction in the BSS group ( 173. 96 cell/mm2 , 8. 12％) was lower than the RL group (253.20 cell/mm2, 10.25％), percentage of corneal endothelial cell variation coefficient increase in the BSS group ( 2. 92％, 8. 36％) was lower compared to the RL group (3. 42％, 9. 96％), decrease of hexagonal cells of corneal endothelium cells presentation percentage in the BSS group (4. 30％, 8. 17％) was lower compared to the RL group (4. 84％, 8. 97％), and the percentage increase of central corneal thickness in the BSS group (4. 69 μm, 0. 89％) was almost equal to the RL group (4. 53 μm, 0. 90％). All of the results regarding difference in density and corneal cell endothelium morphology between the two groups did not reveal any statistically significant difference (P>0. 05). Inflammatory variable in the two groups were even.? CONCLUSION: BSS and RL were equal in their capability of maintaining endothelial cell loss and endothelial cell morphologic change in senile cataract patients after phacoemulsification.