Background: Arachnoid cysts (AC) can cause a wide spectrum of clinical symptoms. Only a limited number of studies have investigated intracranial pressure in patients with arachnoid cysts. We wanted to investigate the relation between intracystic pressure, preoperative complaints, and post-operative symptom relief in adult patients operated for a unilateral, temporal arachnoid cyst.
Material and methods: Prospective, population-based study including 38 adult (>18 years) patients (mean age 43 years, range 18-69), with a previously untreated unilateral, temporal arachnoid cyst.
Results: For all cyst types, the mean pressure was 131 mm H2O. The main preoperative complaints were headache and dizziness/nausea. By median split, all patients were dichotomized into a low pressure (<130 mm H2O) group, or a high pressure (>130 mm H2O) group. Patients with high intracystic pressure had a significantly higher preoperative VAS-score (54.7) than that found in patients with low intracystic pressure (39.4). Both pressure groups had a significant fall in VAS-score after surgical decompression of the cyst. Intracystic pressure correlated significantly with arterial pCO2 and mean arterial pressure.
Conclusion: There was a significant correlation between intracystic pressure and the preoperative level of complaints. Mean intracystic pressure in adult patients with unilateral, temporal arachnoid cysts, however, seems to lie within the limits of a normal intracranial pressure. We therefore hypothesise that other factors than absolute pressure, such as altered compliance and impedance of the brain may be involved in the patophysiology of intracranial arachnoid cysts.
- arachnoid cyst
- intracystic pressure