Three new, pneumatically activated needle holders have been described, suitable for microsurgical and vascular procedures, particularly in magnified fields. Suture techniques have been described and the results of experiments in homotransplanted stomachs and small-vessel surgery reported.
Atherosclerotic stenosis of the intracranial portion of the internal carotid artery (SIPHON) may be the cause of neurologic symptoms. The frequency and severity of these lesions were studied in 226 vessels subjected to conventional two-plane carotid angiography, and the impact of sequential or tandem lesions on cerebral flow was assessed in the 167 arteries from this group that also underwent Gee oculoplethysmography (OPG-Gee), a commonly accepted indicator of the physiologic importance of internal carotid stenosis. Atherosclerotic involvement of the SIPHON was present in 46% (103/226) of the vessels studied, including six total occlusions, 11 severe stenoses (severe, 80% to 99% area reduction [AR]), 27 moderate stenoses (moderate, 50% to 79% AR), 40 mild stenoses (mild, 10% to 49% AR), and 19 instances of mural disease (MUR). This was compared with a 73% rate (166 of 226) of proximal internal carotid artery (PICA) stenosis in the neck, including six to 43 severe, 29 moderate, 50 mild, and 38 MUR. There was little correlation (r = 0.33) between the degree of angiographic stenosis in the PICA and the SIPHON. All of the totally occluded arteries had a positive OPG-Gee, whereas a positive study was noted in only 6% (7 of 109) of the arteries with less than moderate stenosis in the PICA. Twenty-one vessels had moderate stenosis of the PICA. Eight of these arteries had an associated moderate or severe lesion in the SIPHON, and seven of eight (88%) had a positive OPG-Gee. The remaining 13 of this subset had had a normal or mildly diseased SIPHON, and 12 of 13 (92%) had a normal OPG-Gee.(ABSTRACT TRUNCATED AT 250 WORDS)
This article reports the results of a multicenter study that compares 333 frequency analysis studies with the continuous-wave Doppler method with angiography. With receiver operating characteristic curves, the study documents the accuracy of the Doppler technique for the diagnosis of extracranial carotid arterial stenosis greater than 45% diameter reduction. It confirms the accuracy of the measurement of the maximal peak Doppler frequency and, in addition, shows that quantitative analysis of the instantaneous Doppler spectrum at peak systole by the measurement of the spectral broadening index is of diagnostic value. Likelihood ratios have been calculated with the use of curve-fitting techniques and it has been demonstrated how both the peak frequency and the spectral broadening index can be used together to improve the certainty of diagnosis. It is concluded that the probability that an individual patient has significant carotid arterial disease can be determined with the measurements of peak frequency and spectral broadening index from the continuous-wave Doppler spectral waveform.
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