Comprehensive Study of Relative Afferent Pupillary Defect in Kanyakumari Medical College, Tamil Nadu

BACKGROUND Relative afferent pupillary defect (RAPD) or Marcus Gunn pupil is a highly sensitive and significant objective clinical finding in eye examination. It can be detected by swinging flashlight test. Its presence indicates unilateral afferent sensory abnormality or an asymmetric bilateral disease. However, it can be determined even in an unconscious patient, requires no complicated gadgets, relies on clinical observation but can be a manifestation of a myriad of disorders affecting the eye or the brain. The goal of our study was to identify the aetiology of relative afferent pupillary defect and ascertain whether the grade of relative afferent pupillary defect correlated with the visual prognosis. METHODS This was a prospective observational hospital-based study. 25 consecutive patients who presented with a clinical diagnosis of relative afferent pupillary defect to the Ophthalmology Department of Kanyakumari Government Medical College in Tamil Nadu from February 2019 to January 2021 were included in the study. The patients were evaluated based on visual acuity, refraction, colour vision, slit lamp, fundus examination, intra ocular pressure (IOP) measurements & fields. Statistical analysis was done by trial version of statistical package for social sciences (SSPS) software. RESULTS Of the 25 cases analysed, 60 % (15) were male, 36 % (9) were females and 4 % (1) children. An analysis of the aetiology revealed that the optic nerve pathology was the predominant aetiology accounting for 60 % (15) of cases, followed by glaucoma 24 % (6) and retinal pathology in 16 % (4). Glaucoma though a bilateral disease has an asymmetrical presentation which led to RAPD. Grade of RAPD correlated well with the visual prognosis. CONCLUSIONS RAPD is a good and valuable clinical tool for any clinician, it is also a useful guide for assessing the management and response to treatment. KEYWORDS Relative Afferent Pupillary Defect, Optic Neuropathy, Retinal Detachment, Glaucomatous Optic Atrophy

Plaque brachytherapy for choroidal melanoma with vitreous haemorrhage: a therapeutic challenge

A 47-year-old man presented with profound loss of vision in right eye and relative afferent pupillary defect. On fundus examination, posterior pole details were obscured due to dense vitreous haemorrhage. B-scan ultrasonography was performed that revealed a mushroom-shaped hyperechoic lesion with medium internal reflectivity on A-scan ultrasonography. After performing contrast-enhanced MRI of the orbit, a diagnosis of choroidal melanoma was established. Patient was managed using plaque brachytherapy based on multiplanar MRI. This was followed 10 months later by pars plana vitrectomy and cataract extraction. Vision postoperatively improved to 20/60. A systematic clinical assessment along with supportive ancillary investigations augments diagnostic accuracy and reduces delay in definitive management.

Optic Nerve Demyelination in IgG4 Anti–Neurofascin 155 Antibody–Positive Combined Central and Peripheral Demyelination Syndrome

Optic nerve demyelination is one of the clinical features of combined central and peripheral demyelination (CCPD), an entity with heterogenous immunopathogenesis and clinical characteristics, overlapping between multiple sclerosis (MS) and chronic inflammatory demyelinating polyneuropathy (CIDP). Of interest, earlier studies among patients with CIDP prior to discovery of antibodies against paranodal protein neurofascin 155 (anti–NF 155) also reported optic nerve dysfunction. We aimed to evaluate optic nerve demyelination among anti–NF 155 CIDP patients. We studied 2 patients with anti–NF 155 CIDP using visual-evoked potentials (VEP) and optical coherence tomography (OCT). Both patients had distal acquired demyelinating symmetric (DADS) subtype CIDP. Other common features were prominent sensory ataxia, hand tremors, significantly elevated cerebral spinal fluid protein, high titre anti–NF 155 antibodies and poor response to corticosteroid and intravenous immunoglobulin (IVIg). No central nervous system neuroradiological abnormality detected. Both had normal visual acuity and colour vision, but one had subclinical right relative afferent pupillary defect (RAPD). VEP of both showed bilateral prolonged P100 latencies. OCT for patient with RAPD demonstrated moderate to severe retinal nerve fibre layer (RNFL) thinning. Identification of optic nerve demyelination among subclinical CIDP with anti–NF 155 antibodies expanded the spectrum of demyelination within the subset of CCPD.

Nonbacterial Thrombotic Endocarditis Related to Adenocarcinoma of the Uterine Cervix

We report a 66-year-old female patient who presented with acute onset of visual loss with relative afferent pupillary defect, hemineglect, hemihypesthesia, and apraxia. Magnetic resonance imaging of the brain demonstrated different stages of ischemic stroke in different vascular territories, suggesting cardiogenic embolism. Past history was significant for advanced-stage adenocarcinoma of the uterine cervix under chemoradiation treatment. On echocardiogram, vegetation at the aortic valve was observed. With the absence of evidence of infectious endocarditis, diagnosis of nonbacterial thrombotic endocarditis was made, and the patient was treated by long-term anticoagulant. This case is unique in terms of the adenocarcinoma cell type of cervical cancer, which is uncommon and has been rarely reported to be related to nonbacterial thrombotic endocarditis.

Secondary glaucoma due to thrombosis of sigmoid and transverse sinus

An 88-year-old female presented with redness in the left eye of one-month duration. On examination, the left eye showed 3 mm of proptosis with dilated and tortuous episcleral vessels and relative afferent pupillary defect. Intraocular pressure was 60 mmHg and showed open angles on gonioscopy with cup disc ratio of 0.8 in OS. A diagnosis of secondary open-angle glaucoma due to elevated episcleral venous pressure (EVP) was made. Magnetic resonance venogram revealed thrombosis of transverse and sigmoid sinus on the left side. This is the first case report of secondary open-angle glaucoma due to elevated EVP following thrombosis of transverse and sigmoid sinus.

An old lady with acute headache and sudden blindness

A 60-year-old hypertensive lady experienced painless sudden visual loss in the right eye when resting at home. There was no traumatic injury, no eye pain, or flashes or floaters, or nausea, but mild right-sided headache for few days. She was not lifting heavy objects, nor straining. She managed to attend the emergency department within 1 h of onset of symptoms by herself walking into the consultation room unaided. Examination showed visual acuity with pinhole of hand movement over the right eye, right relative afferent pupillary defect and normal intraocular pressure of 15 mmHg. Extraocular movement was full without diplopia or pain. Eyes were not injected, and slit lamp examination was normal with clear cornea. Acute management of vascular causes of acute blindness and the role of hyperbaric oxygen therapy in ophthalmological disease in Hong Kong will be discussed.