Relationship between macular perfusion and lesion distribution in diabetic retinopathy.

BACKGROUND/OBJECTIVES: To assess the relationship between macular vessel density metrics and foveal avascular zone (FAZ) characteristics on optical coherence tomography angiography (OCTA) and lesion distribution in eyes with diabetic retinopathy (DR). SUBJECTS/METHODS: Patients with DR who underwent both Optos ultrawidefield (UWF) pseudocolor imaging and macular OCTA (Cirrus Angioplex, 6 × 6 mm) were included in this cross-sectional observational study. The distribution of DR lesions was assessed by comparing each of the peripheral ETDRS extended fields (3-7) against their corresponding ETDRS field, hence eyes were defined as either having predominantly peripheral lesions (PPL) or predominantly central lesions (PCL). En face OCTA images from the superficial and deep capillary plexuses (SCP and DCP) were then analysed using Image J software. Perfusion density (PD), vessel length density (VLD), and fractal dimensions (FD) were calculated following binarization and skeletonization of the images. RESULTS: Out of 344 eyes, 116 (33.72%) eyes had PPL and 228 (66.28%) eyes had PCL. For all DRSS levels, VLD, PD, and FD were not significantly different between eyes with PPL and PCL. The FAZ in eyes with PPL, however, was found to be more circular in shape compared to eyes with PCL (p = 0.037). CONCLUSION: Although the presence of PPL has been associated with a higher risk for diabetic retinopathy progression, the macular perfusion is similar in eyes with PPL and PCL. The FAZ is more circular in eyes with PPL, but the clinical relevance of this difference remains to be defined.

SLIViT: a general AI framework for clinical-feature diagnosis from limited 3D biomedical-imaging data.

We present SLIViT, a deep-learning framework that accurately measures disease-related risk factors in volumetric biomedical imaging, such as magnetic resonance imaging (MRI) scans, optical coherence tomography (OCT) scans, and ultrasound videos. To evaluate SLIViT, we applied it to five different datasets of these three different data modalities tackling seven learning tasks (including both classification and regression) and found that it consistently and significantly outperforms domain-specific state-of-the-art models, typically improving performance (ROC AUC or correlation) by 0.1-0.4. Notably, compared to existing approaches, SLIViT can be applied even when only a small number of annotated training samples is available, which is often a constraint in medical applications. When trained on less than 700 annotated volumes, SLIViT obtained accuracy comparable to trained clinical specialists while reducing annotation time by a factor of 5,000 demonstrating its utility to automate and expedite ongoing research and other practical clinical scenarios.

The relationship of diabetic retinopathy severity scales with frequency and surface area of diabetic retinopathy lesions.

PURPOSE: To assess the relationship between qualitative diabetic retinopathy (DR) scales with the precise numbers and surface area of DR lesions within the Early Treatment Diabetic Retinopathy Study (ETDRS) standard seven field (S7F) region on ultrawide-field (UWF) color fundus images. METHODS: In this study, we collected UWF images from adult patients with diabetes. Poor-quality images and eyes with any pathology precluding assessment of DR severity were excluded. The DR lesions were manually segmented. DR severity was graded according to the International Clinical Diabetic Retinopathy (ICDR) and AA protocol by two masked graders within the ETDRS S7F. These lesions' numbers and surface area were computed and correlated against the DR scores using the Kruskal-Wallis H test. Cohen's Kappa was performed to determine the agreement between two graders. RESULTS: One thousand five hundred and twenty eyes of 869 patients (294 females, 756 right eyes) with a mean age of 58.7 years were included. 47.4% were graded as no DR, 2.2% as mild non-proliferative DR (NPDR), 24.0% as moderate NPDR, 6.3% as severe NPDR, and 20.1% as proliferative DR (PDR). The area and number of DR lesions generally increased as the ICDR level increased up to severe NPDR, but decreased from severe NPDR to PDR. There was perfect intergrader agreement on the DR severity. CONCLUSION: A quantitative approach reveals that DR lesions' number and area generally correlate with ICDR-based categorical DR severity levels with an increasing trend in the number and area of DR lesions from mild to severe NPDR and a decrease from severe NPDR to PDR.

Microperimetry in Retinal Diseases.

Retinal microperimetry (MP) is a procedure that assesses the retinal sensitivity while the fundus is directly observed, and an eye tracker system is active to compensate for involuntary eye movements during testing. With this system, the sensitivity of a small locus can be accurately determined, and it has become an established ophthalmic test for retinal specialists. Macular diseases are characterized by chorioretinal changes; therefore, the condition of the retina and choroid requires careful and detailed evaluations to perform effective therapy. Age-related macular degeneration is a representative retinal disease in which the macular function has been evaluated by the visual acuity throughout the course of the disease process. However, the visual acuity represents the physiological function of only the central fovea, and the function of the surrounding macular area has not been sufficiently evaluated throughout the different stages of the macula disease process. The new technique of MP can compensate for such limitations by being able to test the same sites of the macular area repeatedly. This is especially useful in the recent management of age-related macular degeneration or diabetic macular edema during anti-vascular endothelial growth factor treatments because MP can assess the effectiveness of the treatment. MP examinations are also valuable in diagnosing Stargardt disease as they can detect visual impairments before any abnormalities are found in the retinal images. The visual function needs to be carefully assessed along with morphologic observations by optical coherence tomography. In addition, the assessment of retinal sensitivity is useful in the presurgical or postsurgical evaluations.

Ethnic Variation in Diabetic Retinopathy Lesion Distribution on Ultra-widefield Imaging.

PURPOSE: To evaluate whether the distribution of diabetic retinopathy (DR) lesions differs among various ethnicities. DESIGN: Multi-center, retrospective cohort study. METHODS: We accrued a cohort of 226 eyes with DR consisting of 51 East Asian eyes, 102 South Asian eyes, 30 Caucasian eyes, and 43 Latino eyes, all evaluated with ultrawide field pseudocolor images. Images were manually annotated for DR lesions and were classified as having predominantly peripheral lesions (PPL) or predominantly central lesions (PCL) using 4 quantitative methods. The percent distribution of PCL to PPL was compared among different ethnicities. RESULTS: Using a single-field lesion frequency-based method, East Asian eyes more frequently demonstrated a PPL distribution (86.3%), whereas South Asian eyes more frequently demonstrated a PCL distribution (64.7%). These findings were also observed when considering only the subset of treatment-naïve eyes. Furthermore, in treatment-naïve eyes without proliferative DR, the percent distribution of PPL to PCL in East Asian eyes was significantly different when compared to other ethnicities (P < .0001 South Asian, P = .035 Caucasian, P = .0003 Latino). The majority of patients (60%-78%) in all ethnic groups had moderate nonproliferative diabetic retinopathy(NPDR), and the same difference between East Asian and South Asian eyes was observed in this subgroup. CONCLUSIONS: The distribution of DR lesions appears to vary among different ethnicities. DR lesions tend to be distributed more peripherally in East Asian eyes compared to other ethnic groups, particularly South Asian eyes, which tend to have more central disease. The prognostic implications of these ethnic differences in DR lesion distribution require further investigation.

Revisiting Anchor Epicanthoplasty in Mild to Moderate Asian Epicanthal Folds: A Clinicopathological Study.

BACKGROUND: To assess the epicanthal fold (EF), eyelid, eyebrow, scar, and patients' satisfaction after anchor epicanthoplasty and upper blepharoplasty and histopathologically compare Asian epicanthal fold skin with non-Asian counterpart. METHODS: Asian Iranians with grade 2 and 3 EF were included. Photographs were taken before and at least 12 months after the surgery. Photoanalysis included EF grade, inter-canthal distance (ICD), margin reflex distance 1 (MRD1), tarsal plate show (TPS), brow fat span (BFS), and eyebrow height. Manchester scar scale score (5-28) and patients' satisfaction score (0-100) were documented. The most medial skin of 5 Asian and 5 non-Asian subjects was histologically compared for the thickness and elastic fiber density and morphology. RESULTS: Included were 89 patients (178 eyelids) with a mean age of 31.6 years and follow-up of 13.1 months. Mean ICD significantly decreased by 3.5 mm (shortening ratio of 9.7%). All grade 2 and almost half of the grade 3 EF disappeared. Significant postoperative increase in mean MRD1 (0.3 mm) and TPS (1.1-1.4 mm) and decrease in BFS (3.3-3.6 mm) and eyebrow height (1.7-3.4 mm) were observed. Revision rate of epicanthoplasty was 7.3%. Mean satisfaction and scar scores were 97.1 and 5.4, respectively. Histopathologically, Asian and non-Asian medial upper eyelid skin was not significantly different. CONCLUSION: Anchor epicanthoplasty eliminated grade 2 and improved grade 3 EF with a high satisfaction and negligible scar. Simultaneous upper blepharoplasty significantly increased MRD1 and TPS and decreased eyebrow height. EF skin was not histologically different from non-Asians. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Postoperative levator function change in patients with unilateral myogenic versus aponeurotic blepharoptosis.

PURPOSE: To compare the change in levator function (LF) after levator resection in patients with unilateral myogenic (MP) and aponeurotic ptosis (AP). METHODS: In a prospective study, patients of >5 years old were included from June 2015 to April 2017. Other types of ptosis, associated strabismus and previous eyelid surgery were excluded. Eyelid examination and photography were performed before and at least 6 months after surgery. Success was defined as Margin reflex distance 1 (MRD1) of within 0.5 mm of the unoperated side. All procedures (levator resection) were performed by or under supervision of one surgeon. RESULTS: There were 58 patients in the MP (mean age: 19.2 years) and 20 in the AP (mean age: 49.5) group with median follow up of 10 months. LF was significantly improved from 5.8 to 7.3 mm in the MP and from 11.8 to 13.6 mm in the AP group. LF improvement was not observed in 17.2% of MP and 25% of AP group (P = 0.5). Mean preoperative LF was significantly (Odd ratio = 1.8) higher in patients with than without LF improvement in the MP group. It was significantly reverse in the AP group (Odd ratio = 0.38). A significantly positive (r = 0.30) and negative (r = -0.72) correlations were observed between preoperative LF and LF improvement in the MP and AP groups, respectively. Success was observed in 90% of AP and 84.5% of MP group. In order of frequency, undercorrection, overcorrection, and contour abnormality were the reasons for failure. No variable significantly affected the success rate in either group. CONCLUSION: Majority of MP and AP showed postoperative LF improvement. While higher preoperative LF was significantly correlated with LF improvement in the MP, it was reverse in the AP group. Success rate was not significantly different between the groups and no factor significantly affected the success in either group.

Eyelash Ptosis in Unilateral Myogenic and Aponeurotic Blepharoptosis: A Prospective, Controlled, Before- and After-Study.

PURPOSES: The purposes of this study were to compare lash ptosis (LP) with contralateral eyelid in patients with unilateral myogenic (MP) and aponeurotic (AP) ptosis before and after the ptosis repair and to assess the correlation between postoperative eyelid height and LP symmetry. METHODS: Patients older than 5 years were included from June 2015 to April 2017. Eyelid examination, LP grading (0-3), and photography were performed before and at least 6 months after ptosis repair. Success of ptosis repair (levator resection) was defined as margin reflex distance 1 within 0.5 mm of the contralateral eyelid; LP improvement, as at least 1 grade improvement at the last follow-up; and LP symmetry, as 2 eyelids being within 1 grade. RESULTS: There were 58 patients with MP and 20 with AP, with mean age of 19.2 and 49.5 years and median follow-up of 10 months. Lash ptosis was observed in 89.5% of ptotic and 33.3% of control eyelids. Mean LP grade was significantly higher in the MP (1.5) than in the AP (1.1), which significantly improved to 0.6 and 0.4, respectively. However, it persisted in 50.9% of MP and 31.2% of AP postoperatively. Lash ptosis symmetry was observed in 97.4% of patients, which was not correlated with margin reflex distance 1 symmetry. Lower levator function was the only significant factor correlated with LP. CONCLUSION: Lash ptosis was significantly worse in MP than in AP. Lower LF was correlated with more severe LP. Ptosis repair resulted in significant improvement of LP and its symmetry with the contralateral eyelid. Lash ptosis symmetry did not correlate with eyelid height symmetry postoperatively.