Lumbar fistula and spontaneous intracranial hypotension - case report

Case presentation: A 53-year-old man with previous history of hypertension and diabetes started with a moderate-severe throbbing headache in October 2022. The pain was located in frontal head and worsened immediately after standing up and after Valsalva maneuver, accompanied by nausea, visual blurring, diplopia, gait ataxia and tinnitus. No trauma history. The patient presented to an emergency neurological care in February 2023 and cranial and spinal magnetic resonance imaging (MRI) showed indirect signs of cerebrospinal fluid (CSF) hypotension, including reduced mammillopontine distance and the descent of cerebellar tonsils through the foramen magnum. Cranial arterial and venous magnetic resonance angiography and CSF analysis revealed no abnormalities. Conservative treatment was unsuccessful. In April 2023, a blind epidural blood patch was performed and was also refractory. The patient continued to have significant orthostatic headaches and a cisternal scintigraphy in August 2023 showed leakage of radioactive material in the lumbar region. A targeted epidural blood patch was performed at the location of the lumbar CSF fistula, resulting in a good response and stability since then. Discussion: Spontaneous intracranial hypotension is a disorder caused by spinal CSF leakage and it typically occurs in patients in their midthirties to midfifties. The classic presentation is acute orthostatic headache, usually bilateral, which can present with migrainelike features, such as nausea and photophobia. The headache presents with moderate to severe intensity and can worse with the Valsalva maneuver. Other symptoms may include vestibulocochlear manifestations such as hypoacusis, dizziness and tinnitus, gait disturbances and cranial nerve palsies. According to the International Classification of Headache Disorders, Third Edition (ICHD-3), a diagnosis of spontaneous intracranial hypotension requires the presence of a headache that developed in temporal relation to low CSF pressure (<60mm) and/or evidence of CSF leak on imaging, in the absence of procedures or trauma. The most common complication is subdural hematoma. Several neuroimaging modalities can aid in diagnosis. Brain MRI may reveal typical findings, but CT-myelography or cisternal scintigraphy can be necessary to locate the CSF leakage. The treatment consists of conservative management such as strict bed rest, hydration and caffeine, epidural blood patches and, in refractory cases, surgical repair of spinal fistula. Final comments: Spontaneous CSF hypotension is rare but debilitating and should be promptly recognized. It typically presents with acute orthostatic headache but can have another associated symptoms. Currently, the epidural blood patch is the treatment of choice, especially when targeted to the exact location of the CSF leakage, resulting in good pain control and improved quality of life.