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Targeted cervical epidural blood patch for the management of refractory headache in a patient with spontaneous intracranial hypotension.

To JNA Readers: Spontaneous intracranial hypotension (SIH) syndrome occurs because of loss of cerebrospinal fluid (CSF) and is an important cause for persistent orthostatic headache.1 We describe the utility of magnetic resonance imaging (MRI) in accurate diagnosis and the effect of targeted epidural blood patch (EBP) placement for successful management of SIH. A 34-year-old lady presented with recurrent episodes of orthostatic headache of 18-month duration. Headache persisted despite maximal medical management. Following examination and investigations, a diagnosis of SIH was made based on International Classification of Headache Disorders (ICHD). MRI of the brain showed (1) descent of splenium, (2) reduced ponto-mamillary distance, (3) descent of cerebellar tonsils, (4) dilated sinus, (5) shriveled appearance of the brain, (6) and pachymeningeal enhancement (Fig. 1A). MR myelography of the spine showed the precise site of CSF leak (Fig. 1C). EBP at C7-T1 spinal level under fluoroscopic guidance was performed using 6mL of autologous blood. Visual analogue score improved from 6 following bed rest and analgesics to 2 postprocedure at 24 hours suggesting significant pain relief. MRI of the brain performed at 48 hours showed normalization of SIH-induced changes (Fig. 1B). At 4-month follow-up, there was no recurrence of headache. SIH occurs because of low CSF pressure caused by spontaneous CSF leakage. It is an important cause for persistent orthostatic headache in fourth or fifth decade of life with an incidence of 0.5/million/y. Neck pain or stiffness, nausea, and vomiting are most common associated symptoms in 50% of patients.1 Although headache appears benign, not treating SIH on time can lead to serious adverse outcomes like stroke and neurological deficits. The diagnostic criteria for SIH as laid down by ICHD require presence of (1) orthostatic headache, (2) Z1 associated symptoms (neck stiffness, tinnitus, photophobia, nausea), and (3) evidence of low CSF pressure or leakage by means of at least 1 modality (brain MRI detecting indirect signs of low CSF pressure, lumbar puncture measuring CSF pressure <6cm H2O, computed tomography myelography, or radionuclide cisternography).2 The most common site of CSF leak is the cervicothoracic junction or upper thoracic region. It generally occurs spontaneously or following a trivial trauma at spinal cord level. As a result of CSF leakage, brain sags causing traction on bridging veins, pain-sensitive meningeal structures, and cranial nerves causing symptoms. Lumbar EBP is performed when actual site of CSF leak cannot be identified. It requires larger volume and often multiple sessions, is dependent on degree of cephalad spread to seal the leak, and is, therefore, associated with high failure. Targeted EBP is recommended when lumbar EBP injection has failed.5 The mechanism of pain relief after EBP is that injected