"Rabbit Ear" scalp deformity caused by massive subdural effusion in infant following bilateral burr-hole drainage

Abstract

Subdural effusion (SDE) in an infant is a rare clinical scenario, which may be secondary to a variety of etiologies. Massive SDE is an extremely rare complication of head injury. It usually runs a self-limiting course. Though neurosurgical intervention is occasionally needed, different methods of surgical procedure for management includes burr-hole alone, burr-holes with subdural drain placement, twist drill craniotomy with drain and even craniotomy. The authors report a rare case of progressive massive SDE, which despite bilateral burr-hole placement and drainage failed and presented with visual deterioration and massive bulge of scalp at burr-hole sites producing rabbit ear sign in a 10 month old infant. Ultimately cystoperitoneal shunt was carried out in a desperate attempt to prevent impending rupture of scalp sutures at sites of previous burr-hole placement. Astonishingly not only complete resolution of hygroma, but visual recovery also took place. Patient is doing well at 6 months following shunt with regaining normal vision and appropriate developmental milestones. A magnetic resonance imaging scan of brain at last follow-up revealed mild ventriculomegaly with subduro-peritoneal shunt in situ and rest of brain was unremarkable. Such cases have not been reported in literature until date.

Keywords: Early intervention; facial disfigurement; head injury; magnetic resonance; subdural effusion; visual deterioration.

Figure 1

Initial non-contrast computerized tomography head at time of injury showing thin bilateral fronto-parietal subdural hygroma with effaced cerebral sulci and gyri

Figure 2

Repeat non-contrast computerized tomography head (a-c) after 10 days showing marked increase in bilateral subdural collection with mass effect. Magnetic resonance imaging T1WI (d) and T2WI (e and f) showing similar findings

Figure 3

(a) Non-contrast computerized tomography head done 20 days following burr-hole drainage showing bilateral tense subdural collection of cerebrospinal fluid density fluid; (b) clinical photograph of patient at the same time, (c) magnetic resonance imaging T2WI at 6 months follow-up showing complete resolution of subdural collection with mild ventriculomegaly; and (d) clinical photograph of patient showing complete subsidence of scalp swelling with reversal of sunset sign compared to (b)