Two cases of medically-refractory spontaneous orthostatic headaches with normal cerebrospinal fluid pressures responding to epidural blood patching: Intracranial hypotension versus hypovolemia and the need for clinical awareness
A 31-year-old male presented in February 2009 with subacute onset occipital and sub-occipital moderate “pressure-like” headaches and neck pain for 2 years. The headache was precipitated by standing or walking and relieved on assuming recumbent position. There was no history of nausea, vomiting, photo-phonophobia, auras, seizures, loss of consciousness, neurological deficit, trauma, cranial/spinal surgery or fever. He had been evaluated at another hospital 1 year back where his MRI brain was normal, but CSF pressure was reported to be “low.” He had been treated with EBP, following, which he had shown good recovery. Clinical examination was normal. CSF opening pressure was 80 mm water. CSF analysis was normal. MRI brain revealed thin subdural hygroma, absence of meningeal enhancement, and mild tonsillar descent [Figure –]. Contrast MRI spine and myelography, and radioisotope cisternography did not reveal an area of CSF leak. Routine laboratory parameters were normal. He was given autologous EBP with reduction in headache by 40% after 5 days followed by complete relief over days without recurrence of headache since then. Follow-up MRI showed normalization of CSF space in the posterior fossa [].