FUNDUS AUTOFLUORESCENCE IN RUBELLA RETINOPATHY: Correlation With Photoreceptor Structure and Function.

PURPOSE: To illustrate altered fundus autofluorescence in rubella retinopathy and to investigate their relationships with photoreceptor structure and function using multimodal imaging. METHODS: The authors report four cases of rubella retinopathy aged 8, 33, 42, and 50 years. All patients had dilated clinical fundus examination; wide-field color photography; blue, green, and near-infrared autofluorescence imaging and spectral domain optical coherence tomography. Two patients also underwent microperimetry and adaptive optics imaging. En face optical coherence tomography, cone mosaic, and microperimetry were coregistered with autofluorescence images. The authors explored the structure-function correlation. RESULTS: All four patients had a "salt-and-pepper" appearance on dilated fundus examination and wide-field color photography. There were variable-sized patches of hypoautofluorescence on both blue and near-infrared excitation in all four patients. Wave-guiding cones were visible and retinal sensitivity was intact over these regions. There was no correlation between hypoautofluorescence and regions of attenuated ellipsoid and interdigitation zones. Hyperautofluorescent lesions were also noted and some of these were pseudo-vitelliform lesions. CONCLUSION: Patchy hypoautofluorescence on near-infrared excitation can be a feature of rubella retinopathy. This may be due to abnormal melanin production or loss of melanin within retinal pigment epithelium cells harboring persistent rubella virus infection. Preservation of the ellipsoid zone, wave-guiding cones, and retinal sensitivity within hypoautofluorescent lesions suggest that these retinal pigment epithelium changes have only mild impact on photoreceptor cell function.

Acute Unilateral Central Serous Chorioretinopathy after Immunization with Pfizer-BioNTech COVID-19 Vaccine: A Case Report and Literature Review.

INTRODUCTION: A 43-year-old Caucasian male presented to our ophthalmology clinic with blurry vision and metamorphopsia in his right eye, 24 hours after receiving the first dose of the Pfizer-BioNTech COVID-19 vaccine. METHODS: Clinical examination and imaging tests were consistent with acute unilateral central serous chorioretinopathy (CSCR) that completely resolved after 2 months without any treatment. He had no significant ophthalmic or medical history. He also lacked the classical risk factors for CSCR such as recent psychosocial stressors, Type-A personality traits, history of exogenous steroid use, connective tissue disorders and obstructive sleep apnea. RESULTS: This appears to be only the second reported case of CSCR, temporally associated with a recombinant COVID-19 mRNA vaccine. We also present a summary of published reports demonstrating intraocular complications associated with the novel recombinant COVID-19 mRNA vaccines. CONCLUSION: Findings in this report should not deter COVID-19 vaccinations given the rarity of aforementioned ocular complications and the greater benefit of protection from COVID-19 infection. Medical practitioners, however, should remain mindful of potential ocular complications, given the greater likelihood of occurrence with increasing vaccination booster rates.

Idiopathic hypertrophic cranial polyneuropathy: a rare cause of orbital pain.

Hypertrophic cranial polyneuropathy (HCP) is sporadically encountered in clinical practice. Aetiologies of HCP have been classified as autoimmune, infectious and demyelinating. However, an accurate diagnosis remains elusive in some cases despite rigorous investigations. These cases represent idiopathic HCP. Given the high clinical variance in presenting symptoms, HCP often leaves medical practitioners in a diagnostic quandary. Here, we seek to expand current knowledge by reporting the first documented case of idiopathic HCP presenting atypically with unilateral orbital pain and exclusively involving the bilateral trigeminal nerves.

Posterior Cortical Atrophy Presenting with Superior Arcuate Field Defect.

An 80-year-old female with reading difficulty presented with progressive arcuate field defect despite low intraocular pressure. Over a 5-year period, the field defect evolved into an incongruous homonymous hemianopia and the repeated neuroimaging revealed progressive posterior cortical atrophy. Further neuropsychiatric assessment demonstrated symptoms and signs consistent with Benson's syndrome.

Semi-automated identification of cones in the human retina using circle Hough transform.

A large number of human retinal diseases are characterized by a progressive loss of cones, the photoreceptors critical for visual acuity and color perception. Adaptive Optics (AO) imaging presents a potential method to study these cells in vivo. However, AO imaging in ophthalmology is a relatively new phenomenon and quantitative analysis of these images remains difficult and tedious using manual methods. This paper illustrates a novel semi-automated quantitative technique enabling registration of AO images to macular landmarks, cone counting and its radius quantification at specified distances from the foveal center. The new cone counting approach employs the circle Hough transform (cHT) and is compared to automated counting methods, as well as arbitrated manual cone identification. We explore the impact of varying the circle detection parameter on the validity of cHT cone counting and discuss the potential role of using this algorithm in detecting both cones and rods separately.

Do recycled spectacles meet the refractive needs of a developing country?

PURPOSE: The aim was to compare the power of spectacles donated to a recycled spectacle program to the custom-made spectacle refractive prescriptions dispensed in a developing country. METHODS: Two hundred consecutive prescriptions were audited in an optical dispensary in Timor-Leste, a developing nation. These refractions were compared against measurements of 2,075 wearable donated spectacles. We determined how many of the 200 prescriptions could be matched to a donated spectacle measurement, how many donated spectacles could be tried for each prescription and how long it would take to find the matched spectacles. RESULTS: There were 1,854 donated spectacles identified as being suitable for comparison with the 200 refractive prescriptions. Twenty-nine out of 200 prescriptions (14.5 per cent) were matched to at least one pair of donated spectacles. CONCLUSION: Recycling all spectacles is not cost-effective in a developing country that has the ability to make custom-made spectacles and dispense ready-made spectacles.

Swimming goggle wear is not associated with an increased prevalence of glaucoma.

BACKGROUND/AIMS: Previous studies have demonstrated a small but significant transient increase in intraocular pressure (IOP) in individuals wearing certain types of swimming goggles. These findings suggested that wearing goggles could represent a significant risk factor for developing and/or worsening of glaucoma in people who swim regularly. The aim of this study was to determine if glaucoma prevalence is increased among adult swimmers. METHODS: A comprehensive ocular examination was performed on 231 members of local swimming clubs and 118 non-swimmers. IOP was measured using iCARE tonometry and visual field testing was performed using Humphrey SITA fast 24-2. Retinal nerve fibre layer thickness was assessed using spectral domain optical coherence tomography. RESULTS: Based on measurements of IOP and visual fields, we did not detect any new cases of glaucoma in our cohort of frequent swimmers. Similarly, we found no difference in the thickness of the retinal nerve fibre layer between swimmers and non-swimmers; the mean right global thickness (GT) was 94.0 µm (IQR 88.0, 100.3) vs 93.0 µm (IQR 89.0, 101.0), respectively (p=0.976), and the median left GT was 93.7 µm (IQR 88.0, 101) in both groups (p=0.799). CONCLUSIONS: These findings suggest that frequently wearing swim goggles does not lead to an increased risk of glaucoma over time in adults.