Kalamangalam et al1 report an illustrative case and the magnetic resonance imaging features of spontaneous intracranial hypotension (SIH). This is a valuable contribution because the variability of clinical symptoms and insensitivity of initial computed tomographic (CT) scan results often form a diagnostic puzzle.
We recently admitted a 51-year-old man, previously in good health, who had a 6-week history of gradually progressive headache and a 1-week history of cognitive decline and ataxic gait. Neurological examination revealed striking fluctuations in consciousness level (Glasgow Coma Scale score, 9-15) with intermittent periods of somnolence and apneas as well as bilateral Babinski reflexes. The initial CT scan showed bilateral subdural effusions and enhancement of the pachymeninges. A subsequent magnetic resonance image showed a general descent of the brain with descent of the cerebellar tonsils into the foramen magnum, flattening of the pons against the clivus, and gadolinium-contrasted meningeal enhancement (Figure 1, A). We suspected SIH, and to detect a cerebrospinal fluid leak, we performed a multislice spiral CT scan with intrathecal contrast of the spinal cord. During the first scans, while the patient was lying on his back, no leak was seen. Subsequently, a second scan was performed 5 minutes after the patient was placed in the prone position. The presence of a cerebrospinal fluid leak was apparent by the observation of massive contrast effusion into the thoracic epidural space, but because of its widespread configuration, the exact level of the leak could not be determined.
Weisfelt M, van den Munckhof P, Majoie CB, Bouma GJ, Bosch DA. Reversal of Acute Neurological Deterioration From Spontaneous Intracranial Hypotension by Lumbar Subarachnoidal Infusion With Normal Saline. Arch Neurol. 2004;61(3):444-445. doi:10.1001/archneur.61.3.444-c