Volume Flow Rate of Common Carotid Artery Measured by Doppler Method and Color Velocity Imaging Quantification (CVI-Q)

BACKGROUND: Common carotid artery (CCA) volume flow rate (VFR) is clinically useful for study of cerebrovascular disease. Color Velocity Imaging Quantification (CVI-Q; Philips Ultrasound International, Irvine, CA), previously reported as accurate and reliable, tracks the flow lumen over the cardiac cycle, as well as mean spatial velocity, which is multiplied by vessel area to obtain VFR. VFR can also be obtained by Doppler sampling for mean velocity, and vessel area based on static B-mode lumen diameter. We compared CCA VFR by CVI-Q and Doppler method (DM), since knowledge of how they compare is crucial when both are used clinically. METHOD: We prospectively studied patients having clinical carotid duplex exams and healthy controls. All had CCA VFR measured by both methods in the same exam session. RESULTS: Thirty-four studies were reviewed. CCA VFR by CVI-Q in those without ICA stenosis was 337 +/- 96 mL/m, and by DM 359 +/- 130 mL/m; P = .33. There was no difference between methods for 50-75% or 75-95% ICA stenosis. In 7 patients with ICA occlusion, and 3 with 95-99% stenosis, VFR was higher by DM than by CVI-Q (Occlusion: 125 vs 58 mL/m, P = .007; 95-99%: 152 vs 63 mL/m, P = .038). There was no statistically significant difference between methods for measurement of the ratio of VFR between right and left CCA. CONCLUSION: In patients with 0-95% ICA stenosis, VFR by CVI-Q and DM showed no difference. For 95-100% ICA stenosis the methods differ; with higher VFR by DM. Side-to-side VFR ratios remain constant, irrespective of VFR method, and can still provide clinically useful information.     

Trancranial Doppler Monitoring of Response to Therapy for Meningovascular Syphilis

Meningovascular syphilis is now quite uncommon, but there have been increasing reports in patients immunocompromised with human immunodeficiency virus. The response of syphilis affecting the central nervous system to antibiotic therapy remains a challenge. This is an even greater challenge in patients who have underlying compromise of the immune system. The authors present a 46-year-old male with recurrent stroke who was found to have cerebrospinal fluid compatible with syphilitic involvement of the central nervous system and a cerebral arteriogram, which revealed focal narrowing of the right middle cerebral artery. The baseline transcranial Doppler study demonstrated increased mean and peak flow velocity within the right middle cerebral artery. Despite a 10-day course of intravenous penicillin, with substantial improvement in the cerebrospinal fluid results, this flow velocity elevation persisted, in a remarkably consistent pattern, over a 4-month follow-up period. Thus, the involved vessel remained patent following treatment, but no clear resolution of the stenotic lesion was observed.     

FDA-Approved Sodium Tetradecyl Sulfate (STS) versus Compounded STS for Venous Sclerotherapy

BACKGROUND: In the area of endovenous chemical ablation (sclerotherapy), there has been much debate regarding sclerosant quality and efficacy. Only sodium tetradecyl sulfate (STS) has garnered Food and Drug Administration (FDA) approval in the United States. OBJECTIVE: The primary objective of this study was to compare clinical performance measures of compounded STS from 27% industrial-strength stock (compounded STS) versus FDA-approved Sotradecol (Bioniche Pharma USA, Inc., Belleville, Ontario, Canada). MATERIALS AND METHODS: Phase I of this study focused on the chemical composition of the drugs, whereas Phase II studied the ablative abilities of the two drugs at comparable concentrations of 3%. RESULTS: We documented the presence of various impurities in compounded STS. No impurities in AngioDynamics STS were found. Our studies suggest that compounded STS may have significant variation in concentration. The AngioDynamics STS concentration was found to be manufactured within a tight tolerance. Segments of incomplete ablation were more frequent in the compounded STS group when compared to the AngioDynamics STS group. This reached statistical significance (p=.02). Primary closure using the Kaplan-Meier statistic demonstrated a trend in the favor of AngioDynamics STS when compared to compounded STS. CONCLUSION: When product quality, efficacy, and liability are carefully considered, we conclude that it would behoove physicians to use pharmaceutical-grade, FDA-approved sclerosant when treating their patients.