Haplogroup heterogeneity of LHON patients carrying the m.14484T>C mutation in India

Purpose: To investigate the clinical and mitochondrial DNA (mtDNA) haplogroup background of Indian Leber Hereditary Optic Neuropathy (LHON) patients carrying the m.14484T>C mutation. Methods: Detailed clinical investigation and complete mtDNA sequencing analysis was carried out for eight Indian LHON families with the m.14484T>C mutation. Haplogroup was constructed based on the evolutionarily important mtDNA variants. Results: In the present study, we characterized eight unrelated probands selected from 187 LHON cases. The overall penetrance of the disease was estimated to be 19.75% (16/81) in eight pedigrees with the m.14484T>C mutation and showed substantially higher sex bias (male:female = 13:3). The mtDNA haplogrouping revealed that they belong to diverse haplogroups; i.e. F1c1, M31a, U2a, M*, I1, M6, M3a1 and R30a. Interestingly, we did not find an association of the m.14484T>C mutation with any specific haplogroup within the Indian population. We also did not find any secondary mutation(s) in these pedigrees, which might affect the clinical expression of LHON. Conclusions: Contrary to earlier reports showing preferential association of the m.14484T>C mutation with western Eurasian haplogroup J and increased clinical penetrance when present in J1 subhaplogroup background, the present study shows that m.14484T>C arose independently in a different mtDNA haplogroup and ethnic background in India, which may influence the clinical expression of the disease

Artificial Intelligence to Detect Papilledema from Ocular Fundus Photographs.

BACKGROUND: Nonophthalmologist physicians do not confidently perform direct ophthalmoscopy. The use of artificial intelligence to detect papilledema and other optic-disk abnormalities from fundus photographs has not been well studied. METHODS: We trained, validated, and externally tested a deep-learning system to classify optic disks as being normal or having papilledema or other abnormalities from 15,846 retrospectively collected ocular fundus photographs that had been obtained with pharmacologic pupillary dilation and various digital cameras in persons from multiple ethnic populations. Of these photographs, 14,341 from 19 sites in 11 countries were used for training and validation, and 1505 photographs from 5 other sites were used for external testing. Performance at classifying the optic-disk appearance was evaluated by calculating the area under the receiver-operating-characteristic curve (AUC), sensitivity, and specificity, as compared with a reference standard of clinical diagnoses by neuro-ophthalmologists. RESULTS: The training and validation data sets from 6779 patients included 14,341 photographs: 9156 of normal disks, 2148 of disks with papilledema, and 3037 of disks with other abnormalities. The percentage classified as being normal ranged across sites from 9.8 to 100%; the percentage classified as having papilledema ranged across sites from zero to 59.5%. In the validation set, the system discriminated disks with papilledema from normal disks and disks with nonpapilledema abnormalities with an AUC of 0.99 (95% confidence interval [CI], 0.98 to 0.99) and normal from abnormal disks with an AUC of 0.99 (95% CI, 0.99 to 0.99). In the external-testing data set of 1505 photographs, the system had an AUC for the detection of papilledema of 0.96 (95% CI, 0.95 to 0.97), a sensitivity of 96.4% (95% CI, 93.9 to 98.3), and a specificity of 84.7% (95% CI, 82.3 to 87.1). CONCLUSIONS: A deep-learning system using fundus photographs with pharmacologically dilated pupils differentiated among optic disks with papilledema, normal disks, and disks with nonpapilledema abnormalities. (Funded by the Singapore National Medical Research Council and the SingHealth Duke-NUS Ophthalmology and Visual Sciences Academic Clinical Program.)

Clinical Profile Of Pediatric Opticneuritis and Visual Outcomes in Indian Population

Optic neuritis in children is not an uncommon disorder following viral illness or vaccination. A limited literature is available on the clinical characteristics, treatment outcomes of pediatric optic neuritis in Indian children. Hence we evaluated the clinical characteristics and visual outcome of pediatric optic neuritis patients who presented to a Neuro ophthalmology department of a tertiary eye care Institution in India

African/Indian Perspective - It Could Be Infective

Various bacterial, viral, fungal and parasitic infections can affect the optic nerve and cause an infective optic neuropathy. Vision loss can be mild to severe depending on the severity of infection . Unsurprisingly literature from Asia and Africa report more "Atypical optic neuritis" cases with wide range of infectious etiologies compared to the west

Bilateral optic neuropathy with central diabetes insipidus in a child

Central nervous system germ cell tumors are rare and they occur in the first two decades of life.[1] Optic nerve germinomas can sometimes mimic optic nerve inflammation.[2] In this case report, we discuss an 11-year-old girl who presented with features of presumed bilateral optic neuritis and developed polyuria and polydipsia, subsequently she was diagnosed to have infiltrative etiology. Her clinical and radiological presentations were initially consistent with inflammatory optic neuropathy. Poor visual recovery to steroid therapy and progressive visual loss warranted the need for optic nerve biopsy which revealed germinoma