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861.
Noncompliance may render migraine prophylaxis useless, but once-daily regimens are better 总被引:4,自引:0,他引:4
WM Mulleners TE Whitmarsh TJ Steiner 《Cephalalgia : an international journal of headache》1998,18(1):52-56
Medicines work better if taken, which must be true of migraine prophylaxis. There is evidence that compliance with regular medication can be badly deficient. To assess how serious the problem might be in routine migraine management, we undertook a covert observational 2-month survey in a specialist headache clinic using objective measures of compliance. Subjects were 38 patients needing prophylaxis with medication prescribed once (od), twice (bd), or three times daily (tds). Medication was dispensed, unknown to them, in Medication Event Monitoring Systems (MEMS) to record openings in real time. Number, timing, and pattern of actual openings were compared with what was expected. Compliance rates averaged 66%, although returned pill counts indicated 91%. A substantial and significant difference was shown between od and bd or tds regimens. Measures of dosing interval—used-on-schedule rate and therapeutic coverage—averaged between 44% and 71%. Once-daily treatment was associated with a used-on-schedule rate more than double those of multiple daily dosing, but still only 66%. We conclude that routine use of drug prophylaxis in migraine may be so seriously undermined by poor compliance that it has little chance of efficacy. Returned-pill counting is inadequate for compliance assessment. 相似文献
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Intracranial circulation: preliminary clinical results with three- dimensional (volume) MR angiography 总被引:5,自引:0,他引:5
Masaryk TJ; Modic MT; Ross JS; Ruggieri PM; Laub GA; Lenz GW; Haacke EM; Selman WR; Wiznitzer M; Harik SI 《Radiology》1989,171(3):793-799
The authors assessed the clinical utility of a magnetic resonance angiography technique in the evaluation of intracranial circulation. Eighteen patients with a low likelihood of cerebrovascular disease (control group) and 40 patients with suspected cerebrovascular disease were imaged with a FISP (fast imaging with steady precession) sequence (repetition time of 50 msec, echo time of 15 msec, velocity compensation in the read and section-select directions with acceleration compensation in the read direction, 15 degrees anisotropic volume, and a 1.25-mm partition thickness). Ninety-four percent of images in the control group and 72% of images in the group with cerebrovascular disease were considered useful for diagnosis. This technique can provide accurate images of intracranial circulation and can be performed in conjunction with two-dimensional spin-echo or gradient-echo imaging. It was most useful in the evaluation of patent intracranial aneurysms, vessel displacement, and large-vessel occlusive disease. Disadvantages included limited field of view, persistent signal voids, limited spatial resolution, and inadequate depiction of lesions with slow flow. 相似文献
864.
To devise and implement an in-plane magnetic resonance angiography examination of the carotid bifurcation capable of producing high-resolution images, the authors examined 19 normal carotid arteries and 14 patients with angiographically documented disease with two flow-correction techniques: a three-gradient, velocity-refocused technique with spin-echo (SE) and gradient-echo sequences, and a four-gradient velocity- and acceleration-corrected SE technique. With use of three equal gradients in the read direction, velocity-related phase changes were minimized by placing the dephasing gradient after the 180 degree pulse and near the read gradient. Acceleration effects were minimized through the use of short echo times and cardiac gating. Both velocity- and acceleration-produced phase changes were corrected with the four-gradient scheme but at the expense of some limitations in spatial resolution. Both techniques consistently produced satisfactory images of the carotid bifurcation in healthy individuals. However, the results indicate that the present gradient-phase modulation techniques have several drawbacks, including susceptibility to patient motion, overlapping with the jugular vein, and inability to image carotid stenosis accurately due to turbulence. 相似文献
865.
The pharmacokinetics and metabolic conversion of the ethynylated estrogens are reviewed. Special emphasis is given to the comparative pharmacokinetics of ethynyl-estradiol in different populations of women. Similarly, the variability of ethynyl-estradiol and mestranol metabolism in humans resulting from presentation of radio-labeled steroid and purification of the metabolic products is presented and discussed. The concepts of estrogen hepatotoxicity are reviewed with respect to the known phenomenon of estrogen oxidative metabolism and covalent binding. Recent evidence for the metabolic removal of the 17alpha-ethynyl group is discussed, and its relationship to estrogen hepatoxicity is considered and related to the covalent binding phenomenon. 相似文献
866.
LR Lee MB BS TJ Sullivan FRACO K Vandeleur FRACO 《Clinical & experimental ophthalmology》1997,25(1):75-77
Background: Orbital squamous cell carcinoma following retinal detachment surgery is a rare condition. A proposed pathogenesis involves implantation of conjunctival squamous epithelium at the time of surgery, with subsequent malignant transformation. Methods/Results: An 81 -year-old Caucasian man presented with a six-month history of a discharging painful red right eye. Ten years earlier a right scleral buckling with an encircling sponge exoplant had been performed. Examination revealed exposure of the sponge, and a large mass in the superomedial conjunctival fornix. Computed tomography revealed a mass invading around the globe in the region of the exoplant. Biopsy revealed squamous cell carcinoma. Orbital exenteration was performed. Conclusion: Orbital squamous cell carcinoma may arise following retinal detachment surgery presumably due to iatrogenic conjunctival implantation deep in the orbit. 相似文献
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870.
Thoracolumbar burst fractures: evaluation with MR imaging 总被引:9,自引:0,他引:9