OBJECTIVE: To study the effects of an externally applied negative abdominal pressure device designed to lower the effects of intra-abdominal pressure (IAP) on headaches and pulsatile tinnitus in severely obese women with pseudotumor cerebri (PTC). DESIGN: Short-term clinical intervention trial in the Clinical Research Center. Days 1 and 3 were 'control' days; on days 2 and 4-6 patients were in the device from 8:00 am to noon and from 1:00 to 5:00 pm, and on nights 7-11 they were in the device from 10:00 pm to 8:00 am. The last four patients were treated in a device with a counter-traction mechanism. SUBJECTS: Seven centrally obese women with PTC. MEASUREMENTS: Headache and pulsatile tinnitus severity were graded by the patient using visual analog scale (1-10) and averaged for the time that the device was in use or not in use. IAP was estimated from urinary bladder pressure (UBP) before and during device use. The internal jugular vein (IJV) elliptical cross-sectional area was measured with B-mode ultrasonography; the timed average velocity was measured by Doppler. RESULTS: There was a decrease in both headache (6.8±0.8 to 4.2±0.8, P<0.05) and pulsatile tinnitus (4.2±0.5 to 1.8±0.5, P<0.02) within 5 min, and in headache (to 2.2±0.8, P<0.01) and tinnitus (to 1.7±0.5, P<0.01) within 1 h of device activation. UBP decreased (P<0.001) from 19.1±3 to 12.5±2.8 cmH2O. Headache remained improved throughout time that the device was used. During the second week, five of seven patients slept in the device without difficulty and four awoke without headache. There was a progressive decrease (P<0.01) in headache during the day after sleeping in the device at night as compared with days 1 and 3 when it was not used (6.5±0.5, day 1; 4.1±0.7, day 3; 3.1±0.8, day 8; 2.3±0.8, day 10). Headaches returned late in the afternoon in two patients; the device was reactivated and headache again improved. Five patients underwent IJV sonography; the IJV area decreased (129±53 to 100±44 mm2, P=0.06) without a change in IJV flow (1004±802 to 1000±589 ml/min) with the device. When activated, the device was pulled into the patient, creating discomfort that was alleviated with the counter-traction mechanism in the last four patients. One patient developed a 5 cm area of blisters that resolved when the device was worn over a hospital gown. CONCLUSIONS: Decreasing IAP relieved headaches and pulsatile tinnitus in PTC. When patients slept in the device, they awoke without headache or tinnitus, which remained markedly improved throughout most of the following day. This study supports the hypothesis that PTC in obese women is secondary to an increased IAP. International Journal of Obesity (2001) 25, 486-490 | 
