Assessment of the Macular Microvasculature in High Myopes With Swept Source Optical Coherence Tomographic Angiography.

Background: The risk of pathologic myopia (PM) increases with worsening myopia and may be related to retinal microvasculature alterations. To evaluate this, we analyzed the macular microvasculature of myopes with swept source-optical coherence tomographic angiography (SS-OCTA) in adolescent and young adult Singaporeans. Methods: This is a prevalent case-control study including 93 young Chinese from the Strabismus, Amblyopia and Refractive error in Singaporean children (STARS, N = 45) study and the Singapore Cohort Study of Risk Factors for Myopia (SCORM, N = 48) studies. Macular vessel density (VD) measurements were obtained from 3 × 3 mm SS-OCTA scans and independently assessed using ImageJ. These measurements were compared between individuals with non-high myopia [non-HM, N = 40; SE >-5.0 diopter (D)] and HM (SE ≤-5.0D, N = 53). Results: The mean macular VD was 40.9 ± 0.6% and 38.2 ± 0.5% in the non-HM and HM, groups, respectively (p = 0.01 adjusted for age and gender). Mean FAZ area in the superficial layer was 0.22 ± 0.02 mm2 in the HM group, which was smaller compared to non-HM group (0.32 ± 0.03 mm2, p = 0.04). Mean deep FAZ area was similar between the two groups (0.45 ± 0.03 mm2 and 0.48 ± 0.04 mm2 in the HM and non-HM groups, respectively, p = 0.70). Conclusions: VD was lower and superficial FAZ area was smaller, in adolescents and young adults with HM compared to non-HM. These findings require validation in prospective studies to assess their impact on the subsequent development of PM.

Scope of Hand Surgery Using Surgeon Administered Local/Regional Anaesthesia.

INTRODUCTION: Hand and wrist surgeries are often carried out under local/regional anesthesia. We describe our experience using Surgeon Administered Local/Regional Anaesthesia (SALoRA) without sedation to deliver acute and elective hand surgery anesthesia in a tertiary public hospital in Singapore. This is in comparison to wide awake local anesthesia no tourniquet, which has been increasing in popularity. METHODS: Retrospective analysis was conducted on all surgeries performed under SALoRA between January 1, 2013, to December 31, 2016, at our institution. Surgeries on areas other than the hand, wrist, forearm, and elbow were excluded. The records were reviewed to analyze the demographics of the patients, profile of cases performed, and their outcomes. RESULTS: Of a total of 3016 cases performed, 1994 patients (1275 men; age, 45.78 ± 16 years) fulfilled the inclusion criteria and were available for analysis for the study period. The case distribution was similar to most other published data on day hand surgery cases. Tourniquet was used in 1357 (68%) of cases with an average operation time of 26 ± 19 minutes. Mean tourniquet use was 24 ± 15 minutes. Detailed analysis will be presented. CONCLUSION: This study shows the versatility of SALoRA in delivering hand surgery in a cost-effective manner. A wide spectrum of surgeries in the hand, wrist, forearm, and elbow can be performed using SALoRA safely. This has increased productivity, efficiency, and use of resources. SALoRA has the advantage of a guaranteed and reliable bloodless field, quick turnaround time without the need of extra personnel and resources needed for patient monitoring to abide by Joint Commission International requirements and the potential risk of systemic adrenaline effects.

Optical Coherence Tomography Angiography Evaluation of the Parafoveal Vasculature and Its Relationship With Ocular Factors.

PURPOSE: To determine the size and characteristics of the superficial and deep foveal avascular zone (FAZ) in healthy adults by using optical coherence tomography angiography (OCT-A), and to ascertain the effects of demographic and ocular parameters on the FAZ size. METHODS: In a prospective cohort study of 117 healthy volunteers, foveal-centered 3 × 3-mm OCT-A scans were manually graded by certified graders to determine the size of the superficial and deep FAZ. Multiple linear regression analyses were performed to evaluate the impact of demographics and ocular factors, including central retinal thickness (CRT), choroidal thickness, axial length (AL), and spherical equivalent (SE) on superficial and deep FAZ areas. RESULTS: The mean age of the participants was 22.5 years, with mean AL of 25.4 mm and mean SE of -4.3 diopters. The mean CRT was 262.8 µm (range, 220-316 µm). The mean superficial FAZ area was 0.24 mm2, while the deep FAZ area was 0.38 mm2 (P < 0.001). Females had a larger superficial (P < 0.001) and deep FAZ (P < 0.001). On univariate linear regression, both superficial and deep FAZ areas had significant correlations with CRT, sex, AL, and SE, but not with age. By multiple linear regression analysis, in normal eyes, superficial FAZ area varied significantly with CRT and sex. Among eyes with high myopia, both superficial and deep FAZ varied significantly with CRT, sex, and choroidal thickness. CONCLUSIONS: The superficial and deep FAZ areas varied significantly among healthy eyes. Factors such as CRT, sex, SE, AL, and choroidal thickness influence the size of the FAZ.