Diagnosis of carotid artery disease – comparison between directional Doppler, Duplex scanner and angiography

Examinations with directional Doppler (DD) with 10 MHz transducer, and pulsed Doppler in combination with two-dimensional sector scanner with 3 MHz transducer (Duplex) were carried out on 100 vessels in 51 patients with transitory ischemic attacks (TIA) and minor stroke within the territory of the internal carotid artery before angiography. The question at issue was to evaluate the accuracy of both methods in discriminating between occlusion and stenosis. A correct diagnosis was made by DD in 92 vessels out of 100 and by Duplex in 98 out of 100. All nine occlusions were correctly diagnosed by Duplex, but only five of them by DD, while the four remaining vessels were considered as stenosis > 50%. Out of 15 stenoses > 50%, 14 were correctly detected by Duplex and 11 by DD. One patient with tortuous vessel without stenosis was classified as > 50% stenosis by Duplex, and one vessel with 1 mm lumen was called occlusion by Duplex and DD. In conclusion, the Duplex scanner offers increased possibility to differ between high-grade stenosis and occlusion of the carotid arteries as compared with earlier non-invasive techniques.     

Einseitige Erblindung als Komplikation der Carotisangiographie

Zusammenfassung Bei einem Patienten mit linksseitiger Carotisstenose trat im Anschluß an eine Carotisangiographie eine Erblindung des linken Auges auf. Die macularen Endäste der A. centralis retinae und die A. cilioretinalis waren durch embolisches Material verschlossen. Zwei weitere Patienten mit spontanem Visusverlust bei Carotisverschluß bzw. -stenose werden vorgestellt. Die Diagnose kann mit gleicher Treffsicherheit auch durch die komplikationsarme Ophthalmodynamometrie gestellt werden. Auf die Möglichkeit angioszintigraphischer Diagnostik wird hingewiesen.

---

Unilateral blindness as a complication of carotid angiography

Summary In a patient with stenosis of the left internal carotid artery acute amaurosis of the left eye was observed after carotid arteriography. The macular branches of the central retinal artery and of the cilioretinal artery were obliterated by embolic material. Two further patients with carotid occlusion and stenosis, in whom spontaneous loss of vision occured, are presented. In such cases the diagnosis may be made with comparable accuracy by other methods, such as ophthalmodynamometry or angioscintigraphy, which entail no risk to the patient.

     

Aberrant internal carotid artery lying within the middle ear

Summary The CT signs of aberrant course of the internal carotid artery are presented and are contrasted against those of anomalously high jugular bulb, glomus tympanicum and cholesterol granuloma.     

The accuracy of duplex scanning in the evaluation of early carotid disease

The accuracy of duplex scanning in 69 comparisons with biplanar angiography in the detection of early carotid disease has been assessed. The various criteria reported for the categorisation of <50% disease have been critically analysed. As part of the study, 50 internal carotid arteries of 25 young, presumed normal medical students of mean age 20 years have been examined. The results suggest that duplex scanning has the ability to grade <50% carotid disease into normal, 1–24% and 25–49% stenosis categories. The most sensitive indicator of early disease is obtained from the real-time B-scan. The waveform changes of the maximum frequency envelope were more sensitive than spectral broadening except where full spectral broadening was present. For confident assessment, the real-time B-scan and pulsed Doppler must always be used in conjunction.     

Reduced hypoxic chemosensitivity in partially paralysed man. A new property of muscle relaxants?

Background: It was hypothesized that non-depolarizing neuromuscular blocking agents impair hypoxic chemosensitivity in man.
Methods: In thirty randomly allocated male volunteers the hypoxic and hypercarbic ventilatory responses were measured during partial paralysis (TOF ratio 0.70) due to either atracurium (n=10), pancuronium (n=10) or vecuronium (n=10).
Results: Hypoxic ventilatory responses were depressed by 306, 287 and 296% (mean SD) at steady-state infusion of atracurium, pancuronium and vecuronium, respectively. At a TOF ratio of >0.90, the HVR was not different from control measurements.
Conclusion: It is concluded that non-depolarizing neuromuscular blocking agents impair hypoxic ventilatory regulation. Further experimental studies are warranted to fully describe the mechanism(s) responsible for this interaction.     

Cerebrovascular occlusive disease in children: A survey

Summary Eight cases of stroke in children treated with surgery are reported. Four of the patients had Moya-moya disease and presented with TIA. They were treated by surgically creating collaterals through the STA-MCA bypass, encephalomyosyangiosis and encephalomyoarteriosynangiosis operations. Three patients with traumatic or idiopathic carotid artery stenosis or occlusion presented with TIA and were treated with STA-MCA bypass. One patient with idiopathic carotid artery stenosis presented with a complaint of a continuous swishing noise in the ear and had a STA-MCA bypass followed by carotid artery ligation. Although stroke in children is usually secondary to systemic disease, there is a group of children with surgically treatable disease who need to be identified and treated. The potential benefit of surgery may depend on the promptness with which a definitive diagnosis is reached.     

Preoperative Duplex on Admission Prevents Unnecessary Carotid Surgery

OBJECTIVES: Our unit policy is to duplex on admission all patients undergoing carotid endarterectomy to confirm patency. The aim of this study was to evaluate whether this had led to avoidance of unnecessary carotid surgery in a significant number of patients. METHODS: Over a 7-year period from January 1997 to December 2003, a total of 475 patients were scheduled for carotid endarterectomy. Of these, 439 patients subsequently underwent carotid endarterectomy. These data were obtained from prospectively collected vascular departmental records and we also hand searched notes of the 36 cancelled patients. RESULTS: There were a total of 36 cancellations for various reasons. Of these, 8 were clearly occluded on duplex. A further 16 were highly suspicious of occlusion on duplex and thus surgery was deferred and selective angiography was undertaken. Of these 9 were confirmed to be occluded on angiogram and a further 4 had severe stenoses or virtual occlusion, 3 patients had a distal internal carotid artery occlusion. Thus a total of 24 patients had an occlusion either diagnosed directly on duplex or because of suspicion on duplex. Unnecessary carotid surgery was avoided in 24 of 475 (5%) of patients. CONCLUSION: This study shows that a preoperative duplex on admission for surgery results in 1 of 20 patients avoiding unnecessary carotid surgery.     

Prevention of ischemic stroke: The role of carotid endarterectomy in symptomatic patients

Carotid endarterectomy (CE) has recently been proved to be beneficial in symptomatic patients with severe (70–99%) appropriate carotid stenosis. After discussing the historical evolution of CE as a possible preventive treatment of ischemic stroke, we review the results of North American and European trials in order to give practical information for the management of cerebrovascular patients.

---

Sommario Recentemente è stata dimostrata l'efficacia della endoarterectomia carotidea (E.C.) in pazienti sintomatici con stenosi carotidea appropriata di grado elevato (70–99%). Dopo una analisi della evoluzione storica della E.C. quale possibile trattamento preventivo dell'ictus ischemico, abbiamo effettuato una revisione critica dei risultati dello studio Nordamericano ed Europeo, con lo scopo di fornire informazioni pratiche per la gestione del paziente cerebrovascolare.

     

磁共振对比剂增强血管造影在颈部血管的应用

对 4 8例临床怀疑椎基底动脉供血不足病例行常规 2 D- TOF和 3D- CEMRA成像检查。 2 D- TOF和 3D-CEMRA图像均能较好地显示与采集层面垂直的颈内、外动脉及椎管内段椎动脉。对与层面平行的椎动脉入颅段及基底动脉环的显示 3D- CEMRA比 2 D- TOF好。 3D- CEMRA显示血管狭窄较 2 D- TOF敏感和准确