Parapapillary atrophy in optic neuropathies: Histology and clinical relevance

Parapapillary atrophy is one of the parameters of the optic nerve head area which are assessed during the ophthalmoscopic examination particularly useful to characterize glaucomatous optic neuropathy. Optical coherence tomography evaluation provides high-resolution images of the optic nerve head and surrounding area, and can be used to study parapapillary atrophy. Different parapapillary atrophy zones were described depending on their histological features and research has been conducted to investigate the possible association between the presence and/ or size of parapapillary atrophy zones and several optic nerve disorders. In this review we discuss the histology and the clinical findings related to parapapillary atrophy in patients with glaucomatous optic neuropathy, non-glaucomatous optic neuropathies (e.g. arteritic and non-arteritic anterior ischemic optic neuropathies; suprasellar and parasellar tumors), and other ocular conditions (e.g. high myopia; age-related macular degeneration). Two different histologic classifications were identified. Parapapillary atrophy was demonstrated in glaucoma and glaucoma-like neuropathies, but not in other types of optic nerve disorders.

Frequency of Color Blindness in Driving License Candidates Presenting in Allied Hospital, Faisalabad

Background: Color vision is an integral part of visual functions. Defective color vision may leadto difficulties in daily activities and even choosing and continuing in a certain profession. Colorvision deficiency or blindness may be congenital or acquired due to retinal or optic nerve disorders Aim: To investigate the frequency of color blindness or weakness in driving license candidates presenting for medical exam, for the year 2019. Methodology: The study design was descriptive cross sectional and the sampling technique wasnon probability convenient sampling. The place of study was eye outdoor of Allied Hospital,Faisalabad. The sample size was 13,637 based on inclusion criteria. The subjects ranged in agefrom 18 years onwards to a maximum presentation of 76 years with mean age as 30.728 ±10.131.Both genders were included in the study. Visual acuity was tested on Snellen’s Chart andrefraction, if needed, was performed to obtain best corrected acuity. Results: The results of the study showed that most of the subjects had 6/6 vision as 96.6% in righteye and 96.5% in left eye, 6/9 as 2.8% and 2.9% and 6/12 as 0.3% and 0.4% respectively for rightand left eye. The frequency of normal color vision was 94%, 4.9% for red green deficiency and 1.1% for color blindness. Conclusion: A frequency of 4.9% and 1.1% for color deficiency and color blindness respectively, in drivers, indicates that color vision must be tested to avoid any possible accidents related todeficient color perception. Keywords: Driving license, colorblindness

Pattern of Orbital Diseases at a Tertiary Oculoplastic Center

Purpose: To determine the causes and frequency of orbital involvement by systemic disorders and non-ocular trauma at a tertiary Oculoplastic centre. Study Design: Descriptive cross-sectional retrospective study. Ophthalmology unit Place and Duration of Study: Department of Ophthalmology, Lady Reading Hospital Medical teaching Institute, Peshawar from January 2012 and Dec 2016. Methods: A total of 45 patients were included in this study. Patients’ demographics, clinical cause of orbitopathy and time delay between the problem noticed by the patient and presentation were recorded. Orbitopathy included the presence of corneal and conjunctival changes, optic nerve disorders, proptosis, orbital bone changes and soft tissue swelling of eyelids. The data was analyzed using SPSS software (version 22). The frequency (percentage) and mean ± standard deviation were reported for categorical variables. Results: Mean age of the patients was 28.89 ± 22.02 years. There were 26 (57.8%) males 19 (42.2%) females. Commonest disorder was Bacterial Infection in 16 (35.6%) patients followed by Thyroid orbitopathy, which was seen in 14 (31.1%) cases. Other causes included Leukemia, Lymphoma, Retrobulbar Hemorrhage, Neurofibromatosis, Neuroblastoma, Maxillary Osteosarcoma, Teratoma and Fungal Infection. Time delay between presentation of orbital swelling and first noticed by patient was 147.02 ± 155.18 weeks in male while in female the time delay was 148.79 ± 146.47 weeks. Conclusion: The commonest inflammation was due to thyroid, commonest infection was bacterial infection and commonest tumor was leukemia. Imaging and proper workup is important to properly treat any orbital disease. Key Words: Orbit, Ocular trauma, Neuroblastoma, Orbital lymphoma.

Role of Gestational Hypertension and Preeclampsia as Risk Factors for Formation of Vascular Disorders of Retina in Remote Period after Delivery

Purpose. To study the correlation between pregnancy, complicated by preeclampsia and gestational hypertension (GH), and formation of retinal vascular and optic nerve disorders in the late postpartum period.Patients and methods. 231 women with different previous pregnancy variants of pathology. Exclusion criteria — presence of systemic endocrine, autoimmune, rheumatic pathology before pregnancy; bad habits. Four groups were formed. 1st main group: pregnancy with GH. 2nd main group: pregnancy with preeclampsia. 1st comparison group: pregnancy on the background of pre-existing hypertension, without proteinuria. 2nd comparison group: edema and/or proteinuria during pregnancy, without hypertension. The control group — physiological process of pregnancy. Period of ophthalmological examination after pregnancy is 6–12 years.Results. Development of various vascular and ischemic disorders of posterior eye segment occurred in 70 women (30.3 %). The periods of their formation after previous pregnancy varied from 3 to 11 years. Their frequency in the 1st and 2nd main groups was statistically significantly higher. The most common were retinal vein occlusion and post-thrombotic retinopathy. The negative outcomes of transferred GH and preeclampsia are no eliminated with delivery and can manifest next years and even decades after it.Conclusion. Нigh risk factors for development of vascular and ischemic disorders of posterior eye segment are transferred preeclampsia, especially with its early onset (20–24 weeks), or premature birth (26–28 weeks); pregnancy, complicated by GH. The risk of developing this eye pathology is highest in women aged 38–40 years and over.

Nicotinamide-Rich Diet in DBA/2J Mice Preserves Retinal Ganglion Cell Metabolic Function as Assessed by PERG Adaptation to Flicker

Flickering light increases metabolic demand in the inner retina. Flicker may exacerbate defective mitochondrial function in glaucoma, which will be reflected in the pattern electroretinogram (PERG), a sensitive test of retinal ganglion cell (RGC) function. We tested whether flicker altered the PERG of DBA/2J (D2) glaucomatous mice and whether vitamin B3-rich diet contributed to the flicker effect. D2 mice fed with either standard chow (control, n = 10) or chow/water enriched with nicotinamide (NAM, 2000 mg/kg per day) (treated, n = 10) were monitored from 3 to 12 months. The PERG was recorded with superimposed flicker (F-PERG) at either 101 Hz (baseline) or 11 Hz (test), and baseline-test amplitude difference (adaptation) evaluated. At endpoint, flat-mounted retinas were immunostained (RBPMS and mito-tracker). F-PERG adaptation was 41% in 3-month-old D2 and decreased with age more in control D2 than in NAM-fed D2 (GEE, p < 0.01). At the endpoint, F-PERG adaptation was 0% in control D2 and 17.5% in NAM-fed D2, together with higher RGC density (2.4×), larger RGC soma size (2×), and greater intensity of mitochondrial staining (3.75×). F-PERG adaptation may provide a non-invasive tool to assess RGC autoregulation in response to increased metabolic demand and test the effect of dietary/pharmacological treatments on optic nerve disorders.