Frank Lai

Determinants of Quantitative Optical Coherence Tomography Angiography Metrics in Patients with Diabetes

Early microvascular damage in diabetes (e.g. capillary nonperfusion and ischemia) can now be assessed and quantified with optical coherence tomography-angiography (OCT-A). The morphology of vascular tissue is indeed affected by different factors; however, there is a paucity of data examining whether OCT-A metrics are influenced by ocular, systemic and demographic variables in subjects with diabetes. We conducted an observational cross-sectional study and included 434 eyes from 286 patients with diabetes. Foveal avascular zone (FAZ) area, FAZ circularity, total and parafoveal vessel density (VD), fractal dimension (FD), and vessel diameter index (VDI) from the superficial capillary plexus OCT-angiogram were measured by a customized automated image analysis program. We found that diabetic retinopathy (DR) severity was associated with increased FAZ area, decreased FAZ circularity, lower VD, lower FD, and increased VDI. Enlarged FAZ area was correlated with shorter axial length and thinner central subfield macular thickness. Decreased FAZ circularity was correlated with a reduction in visual function. Decreased VD was correlated with thinner macular ganglion-cell inner plexiform layer. Increased VDI was correlated with higher fasting glucose level. We concluded that the effects of ocular and systemic factors in diabetics should be taken into consideration when assessing microvascular alterations via OCT-A.

Clinical Outcomes of Cataract Surgery in Very Elderly Adults

To investigate the clinical outcomes of cataract surgery elderly adults.

Ethnic differences in the association of SERPING1 with age-related macular degeneration and polypoidal choroidal vasculopathy.

Neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) are leading causes of irreversible blindness in developed countries. In this study, we investigated the association of single nucleotide polymorphisms (SNPs) in the serpin peptidase inhibitor, clade G, member 1 (SERPING1) gene with neovascular AMD and PCV. Two haplotype-tagging SNPs, rs1005510 and rs11603020, of SERPING1 were genotyped in 708 unrelated Chinese individuals: 200 neovascular AMD, 233 PCV and 275 controls. A meta-analysis was also performed for all reported associations of SERPING1 SNPs with AMD and PCV. None of the tagging SNPs had a significant association with neovascular AMD or PCV (P > 0.05) in our study cohort. The meta-analyses showed that the most-studied SNP rs2511989 was not significantly associated with all forms of AMD, neovascular AMD, or PCV in East Asians (P = 0.98, 0.93 and 0.30, respectively) but was associated with AMD in Caucasians (P = 0.04 for all AMD and 0.004 for neovascular AMD). Therefore, the results of our study and meta-analysis suggest that SERPING1 is not a major genetic component of AMD or PCV in East Asians but is a genetic risk factor for AMD in Caucasians, providing evidence for an ethnic diversity in the genetic etiology of AMD.

Classification of Exudative Age-Related Macular Degeneration With Pachyvessels on En Face Swept-Source Optical Coherence Tomography

Purpose The purpose of this study was to classify exudative maculopathy by the presence of pachyvessels on en face swept-source optical coherence tomography (SSOCT). Methods Consecutive patients with signs of exudative maculopathy underwent SSOCT, fluorescein and indocyanine green angiography (ICGA), ultra-widefield fundus color photography, and autofluorescence examinations. Images were analyzed in a masked fashion by two sets of four examiners in different sessions: (1) the presence of pachyvessels in en face OCT and (2) features of exudative maculopathy in conventional imaging modalities. Quantitative data obtained were subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI), which was the ratio of choroidal vessels lumen area to a specified choroidal area from binarized cross-sectional OCT scans. Results Pachyvessels was observed in 38 (52.1%) of 73 eyes. The pachyvessels group was associated with younger age (69.1 ± 9.4 years, odds ratio [OR] = 0.95, 95% confidence interval [95% CI] = 0.90-0.97, P = 0.04), presence of polypoidal lesions (OR = 3.27, 95% CI = 1.24-8.62, P = 0.01), increased SFCT (OR = 1.08, 95% CI = 1.02-1.14, P < 0.01), and increased CVI (65.4 ± 5.3, OR = 1.12, 95% CI = 1.02-1.23, P = 0.01). In multivariate regression, CVI significantly correlated with pachyvessels (OR = 1.24, 95% CI = 1.03-1.55, P = 0.04). Conclusions Exudative maculopathy could be classified based on differences in choroidal vasculature morphology. Current results implied that choroidal hemodynamics may be relevant to variable natural history and treatment response in neovascular AMD and polypoidal choroidal vasculopathy.

Lacrimal gland abscess in children: Two case reports and literature review

ABSTRACT Acute suppurative bacterial dacryoadenitis (ASBD) with abscess formation is rarely seen in clinical practice. A retrospective review of medical records in the past 8 years identified two unilateral cases in children, one developed presumably after methicillin-sensitive Staphylococcus aureus (MSSA) conjunctivitis and the other due to community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection. Computerized tomography scans showed globe indentation by the enlarged lacrimal glands with rim-enhancing lesions. After failing to respond to intravenous antibiotics, both abscesses resolved promptly with surgical drainage without any long-term sequelae.