Sub Acute Sclerosing Panencephalitis presenting as Hemorrhagic necrotizing retinitis

Advanced Eye Centre and Department of Neurology* Samyak Mulkutkar Mohit Dogra Reema Bansal Vivek Lal* Amod Gupta   Advanced Eye Centre and Department of Neurology* Post Graduate Institute of Medical Education and Research, Chandigarh Correspondence: Amod Gupta Professor of Ophthalmology, Advanced Eye Centre Post Graduate Institute of Medical Education and Research Chandigarh -160012 dramodgupta@gmail.com

Ocular History 21-year-old woman Presented in April 2014 H/o sudden loss of vision RE: 20 days, LE:15 days BCVA: RE counting fingers, LE no light perception

Past History H/o Measles infection in childhood

Ocular examination at First presentation LE relative afferent pupillary defect RE: pale optic disc, perifoveal sheathing of vessels, foveal atrophy. LE: Disc edema, dilated tortuous retinal vessels, extensive necrosis of macula, retinal and sub-retinal hemorrhages, sub-retinal fluid. Active retinitis nasal to the optic disc.

Fig.1 Right eye, Fundus photograph showing pale optic disc, featureless macula and atrophic fovea Fig.2 Left eye, Fundus photograph showing disc edema with dilated tortuous blood vessels and hemorrhagic macular necrosis and exudative fluid Fig.3 Left eye, Fundus photograph showing active retinitis edge nasal to the optic disc

OCT RE: cystic changes and diffuse foveal atrophy LE: Disintegration of all retinal layers except ILM and Bruch’s membrane suggestive of extensive retinal necrosis, and sub-retinal exudation in the macula

Neurological examination No significant clinical abnormality. MRI Brain: Well defined ovoid area of T2 and FLAIR hyper-intensity in sub cortical area, deep white matter in bilateral fronto-parietal region relatively bulky left optic nerve with subtle T2 hyper-intensity in pre-chiasmatic part and left side of optic nerve

MRI Brain shows well defined ovoid area of T2 and FLAIR hyper-intensity in the subcortical area and deep white matter in bilateral fronto-parietal region A relatively bulky left optic nerve with subtle T2 hyper-intensity in pre-chiasmatic part and left side optic nerve is also seen

CSF analysis CSF/ Serum Quotient reference (CSFQ ref): 7.58 (value of more than 1.5 is considered to be indicative of Measles specific antibody synthesis in CNS) Serum Measles IgG and IgM levels : within reference values

EEG Intermittent episodes of Delta-Theta slowing with occasional spike wave discharges arising independently from bilateral central hemispheres along with mild diffuse Theta slowing.

Final Diagnosis SSPE Typical fundus and OCT findings Elevated CSF/ Serum Quotient reference (indicative of Measles specific antibody production in CNS) Subnormal EEG changes

2 weeks follow up RE Progressive foveal atrophy and optic disc pallor LE Progressive necrosis of retina sparing ILM BCVA at 2 weeks: RE counting fingers, LE no light perception

Fig.5 Fig.4 Fig.4 Right eye, Fundus photograph at 2 weeks showing pale optic disc & atrophic fovea Fig.5 Right eye, OCT at 2 weeks follow up showing foveal atrophy Fig.7 Fig.6 Fig.6 Left eye, Fundus photograph at 2 weeks follow up shows pale optic disc, atrophic fovea and resolving hemorrhagic retinitis Fig.7 Left eye, OCT at 2 weeks follow up showing characteristic disintegration of all retinal layers

Conclusion Though ocular findings do not constitute a part of the diagnostic criteria of SSPE, ophthalmic manifestations may be the first sign of the disease. Necrosis of all retinal layers barring the ILM and Bruch’s membrane as seen on OCT in our case is a new observation. Early diagnosis of SSPE is critical before neurological involvement, when the disease becomes invariably fatal, and requires high index of suspicion. The OCT findings as noted in this patient may provide a vital clue to the early diagnosis of SSPE.