CT Scan and MRI spinal imaging findings in Spontaneous Intracranial Hypotension: a case report Sérgio Cardoso Radiology Department - Hospitais Cuf Lisbon, Portugal

Spontaneous Intracranial Hypotension (SIH) Syndrome of low cerebral spinal fluid (CSF) volume, secondary to CSF leakeage into the epidural space (spinal meninges structural weakness) No previous history of surgery or lombar puncture; Presence of trivial traumatic events in 1/3 of patients No epidemiological data available ( annual incidence 5/100.000 ) Affects young and middle age individuals; female/male ratio 2:1 Variable clinical presentation ; postural headache is the most common manifestation Delay in diagnosis is very frequent

Case Report 34 yo female Previously healthy, with no relevant issues in her past medical history Suddenly onset of permanent severe, cervical pain one week before first observation, with no relief or exacerbation features No other symptoms, as headache, fever, systemic In physical examination the only finding was some degree of neck stiffness, with otherwise normal physical and neurological examination Laboratorial workout showed no significant abnormalities (normal CRP, normal blood count, normal renal and hepatic function)

Cervical Spine CT Scan (03/06/2010) Antero-lateral hyperdense epidural collection

Brain MRI (03/06/2010) No abnormal findings

Spine MRI (03/06/2010) EPIDURAL HEMATOMA ? SPINAL AVM ? Spine MRI - spinal epidural collection - dilated epidural veins - enlargement of epidural venous plexus - dural enhancement Normal brain MRI errounesly dismissed SIH diagnosis; with the spine findings at this time this hypothesis should have been considered

Spinal Angiography No spine AVM No signs of medular compression No clinical deterioration → conservative attitude

Spine MRI (30/06/2010) Typical neuroimaging features of SIH - epidural fluid collections dural sac collapse- festooned appearence dural enhancement epidural venous plexus dilatation - dilated epidural veins -C1\C2 sign (absent)

Dorsal and Lombar Spine MR (30/06/2010) - collapse of dural sac dilatation of epidural venous plexus

Brain MRI (30/06/2010) Typical brain neuroimaging features of SIH Subdural fluid collections Enhancement of pachymeninges Engorgemnt of venous structures Pituitary hyperemia Sagging of the brain → SEEPS

CT Myelography (22/07/2010) Persistent symptoms with conservative therapy (bed rest and hydratation) → CT myelography The differential opacification of thecal sac and the ventral fluid collection → sign of communication The exact location of the communication could not be determined

EVOLUTION Conservative measures uneffective (bed rest, oral hydration, caffeine intake) Epidural blood patch (27/07/2010) → clinical improvement Spine and Brain MR (24/08/2010) 03/06/2010 24/08/2010 30/06/2010 24/08/2010 24/08/2010

Take Home Messages Spontaneous intracranial hypotension (SIH) is not rare, but is still underdiagnosed Clinical and imaging findings are widely variable CT Myelography is the study of choice to identify the CSF leak, but is not always necessary to make the diagnosis The role of spinal imaging findings in SIH is not well established, but awareness to abnormalities at this level can lead to an earlier diagnosis