Clinical Problem Solving: Decreased Level of Consciousness and Unexplained Hydrocephalus

Abstract

We present a clinical reasoning case of 42-year-old male with a history of type 1 diabetes who presented to hospital with decreased level of consciousness. We review the approach to coma including initial approach to differential diagnosis and investigations. After refining the diagnostic options based on initial investigations, we review the clinical decision-making process with a focus on narrowing the differential diagnosis, further investigations, and treatment.

Keywords: [13] other cerebrovascular disease/stroke; [146] all medical/systemic disease; [18] coma; [295] critical care; case report.

Figure 1.

Computed tomography (CT) head without contrast upon initial presentation. (A) Axial cut of the posterior fossa demonstrates diffuse bilateral cerebellar edema with some involvement of the pons. (B) Sagittal cut demonstrates fourth ventricle compression and obstructive hydrocephalus. (C) Axial cut at the level of the third ventricle demonstrates obstructive hydrocephalus with enlargement of the third and lateral ventricles.

Figure 2.

Magnetic resonance imaging (MRI) brain on initial presentation, displaying T1-sequences with gadolinium-based contrast (A, C) and unenhanced T2 fluid-attenuated inversion recovery (FLAIR) sequences (B, D). Axial cuts of the cerebellum demonstrate diffuse cerebellar T2 hyperintensity (B) without enhancement (A) or diffusion restriction (not shown), suggestive of cerebellar vasogenic edema. There is also mild T2 hyperintensity involving the pons (D), again without enhancement (C). Fourth ventricle compression is evident (A–D).

Figure 3.

Repeat MRI brain 3 weeks after treatment, displaying T1-sequences with gadolinium-based contrast (A, C) and unenhanced T2 FLAIR sequences (B, D). Axial cuts of the cerebellum demonstrate significant improvement of T2 hyperintensity involving bilateral cerebellar hemispheres without enhancement (A, B), suggesting resolving vasogenic edema. T2 hyperintensity in the pons is also significantly reduced (C, D). Fourth ventricle compression is improved (A–D).