The significance of the pharyngeal veins during carotid endarterectomy: description of an anatomical triangle.

Injuries to the hypoglossal and vagus nerves are the most commonly reported injuries during carotid endarterectomy. While unilateral single nerve injury is usually well tolerated, bilateral or combined nerve injuries can pose a serious threat to life. This study aims to increase awareness of the inferior pharyngeal vein, which usually passes posterior to the internal carotid artery but sometimes crosses anterior to it. Injury to either or both hypoglossal and vagus nerves can occur during control of unexpected haemorrhage from the torn and retracted edges of the inferior pharyngeal vein. We recommend careful ligation and division of this vein. In addition, we observed in 9 (17.3%) of the 52 operations that the pharyngeal vein formed a triangle with the vagus and hypoglossal nerves when it passes anterior to the internal carotid artery.

Vascular resistance in primary open angle glaucoma.

PURPOSE: To explore any difference in vascular resistance between normal and glaucoma subjects using a continuous wave Doppler technique. METHOD: The Resistance Index, RI, was calculated in two orbital vessels of 20 glaucoma patients all of whom had pressures over 23 mmHg and 15 age matched normal subjects. The haemodynamic relationship between the supratrochlear and a vessel at the optic disc, presumed central retinal artery, is expressed as RIST/RICRA. RESULTS: In 30 normal eyes the ratio was >1 m, in 10 glaucoma patients it was >1. In those glaucoma eyes which were <1, 14 improved after treatment to >1. The remaining 16 eyes which showed no change in the ratio were the eyes with moderate to severe field loss. CONCLUSION: An altered, increased, peripheral vascular resistance with reduced diastolic flow in small orbital vessels has been demonstrated in glaucoma subjects. This was not altered by treatment in the more severely affected eyes.

Immunoproliferative small intestinal disease: Mediterranean lymphoma and alpha heavy chain disease.

Gastrointestinal lymphoma, uncommon in the West, is far more prevalent in developing countries where it falls into two groups: 'Western'-type lymphomas, similar to those seen in developed countries, and the so-called Mediterranean-type lymphoma. It is now accepted that Mediterranean lymphoma represents, in the majority if not in all cases, the late stage of alpha heavy chain disease (alpha-HCD). This disease is characterized by abnormal secretion of an immunoglobulin fragment; alpha-HCD and Mediterranean lymphoma constitute two ends of a spectrum of pathology now classified as immunoproliferative small intestinal disease (IPSID). IPSID is associated predominantly with poor socioeconomic conditions; patients present with progressive malabsorption in the second and third decades of life. Diagnosis is established by small bowel biopsy, with or without high serum levels of the alpha heavy chain protein. Treatment consists of an initial staging laparotomy, with debulking of lymphomatous deposits if appropriate, followed by chemotherapy or radiotherapy. Overall prognosis is poor but the recent use of doxorubicin-based chemotherapy offers some hope for the future.

Reproducibility of Doppler ultrasound measurement of resistance index in renal allografts.

In recent years measurements of arterial blood flow in the renal allograft have been studied in an attempt to provide a non-invasive method of diagnosing and monitoring post-transplant renal dysfunction. Many studies have involved measurement of the resistance index (RI) of arterial blood flow. Although the reproducibility of the technique has been studied in other areas of application, no such studies have been performed on the renal allograft. In this study we attempted to evaluate the reproducibility of the measurement of the RI of the interlobar artery in the renal allograft. 18 renal allograft recipients with stable functioning grafts were studied twice by each of two experienced sonographers using a colour-coded duplex Doppler ultrasound scanner, in order to determine the intraobserver and interobserver variability in the measurement of RI of the interlobar arteries in the allograft. Variability was small and although interobserver variability exceeded intraobserver variability, both were within repeatability limits adopted by the British Standards Institution. The results suggest that measurement of the RI of the interlobar artery of renal allografts is repeatable and reproducible when performed by experienced operators.

Monitoring renal allograft rejection with duplex sonography.

Thirty-six renal allograft recipients were monitored by serial duplex Doppler ultrasound studies post-transplant and during early rejection. A separate reproducibility study demonstrated no significant inter- or intra-operator variability in measurements of resistive index of an interlobar artery (RI) (2.1% [1.5%] and 3.2% [2.3%] respectively, mean [standard error] of coefficients of variance). Twenty-one patients had rejection within 3 weeks of transplantation. These grafts showed greater overall rises in the RI, from day 2 to day 5 post-transplant, than the grafts which had no rejection. Eleven of the 21 patients required more than one course of methyl-prednisolone for persistent or recurring rejection. These grafts had higher RI on the day rejection was diagnosed (81 [7.3], median [interquartile range]) compared with the remaining 10 patients (68.6 [8.7]). The 11 grafts with persistent rejection had higher RI (p less than 0.005, Mann-Whitney U-test) on day 2 post-transplant (76 [3.9]) compared with the 10 grafts successfully treated with a single course of methyl-prednisolone (63.2 [10.9]). This study demonstrates that grafts with an RI of greater than 70 on day 2 post-transplant are likely to have rejection requiring additional treatment (sensitivity--100%, specificity--80%). These patients may be candidates for earlier or alternative anti-rejection therapy.

Local neurological complication during carotid endarterectomy.

In a prospective study of 52 carotid endarterectomies there were 13 temporary cranial nerve injuries in 12 patients (25%); 7 hypoglossal nerve injuries (13.5%), 3 were asymptomatic (5.8%), 2 had mild speech difficulty (3.8%) and 2 had severe difficulty with deglutition and articulation (3.8%). A full recovery was made within 3 months in all 7 patients. Although 10 patients (19.2%) developed a hoarse voice, indirect laryngoscopy only indicated damage to the ipsilateral recurrent laryngeal nerve in 3 patients (5.8%). Both the voice and vocal cord movement returned to normal within 6 months in 2 patients and a 9 months in the third. The marginal mandibular branch of the facial nerve was injured in 3 patients (5.8%) and all recovered completely within 3 months. Following injury to the great auricular and the transverse cervical nerves injury, 13 patients (25%) had persistent irritation and paraesthesia during shaving and in cold weather lasting up to 18 months after operation. Carotid endarterectomy is associated with a much higher incidence of local nerve injury than retrospective surveys would indicate.

Prospective assessment of carotid endarterectomy by clinical and ultrasonic methods.

Sixty-three carotid endarterectomies in 60 patients were followed by clinical and duplex scanning at 2 weeks postoperatively and at 3-monthly intervals for 3 years (mean 18 months). Four patients died (two of stroke, two of myocardial infarction) and four survivors had recurrent ipsilateral symptoms. Two had an immediate mild hemiparesis which recovered completely within 36 h; in both, the endarterectomized arteries were patent on scanning. The other two experienced amaurosis fugax for 2-3 weeks at 2 and 24 weeks; scanning showed that the sites of both endarterectomies had become occluded. Ultrasound assessment at 2 weeks showed that 43 of 61 (70.5 per cent) endarterectomized arteries were widely patent. There were three occlusions, one stenosis of greater than 75 per cent, three stenoses of greater than 50 per cent and eleven stenoses of less than 50 per cent. At 6 months a total of five vessels were occluded, with greater than 75 per cent stenosis in three and greater than 50 per cent stenosis in eight. At latest follow-up, six of eight arteries with greater than 50 per cent stenosis shown earlier had scans which had reverted to normal. Tacking down of the distal intima was associated with higher incidence of restenosis and occlusion (P less than 0.01). Women were more predisposed to restenosis by neointimal hyperplasia (P less than 0.05). All restenosis occurred within the first 6 months postoperatively (26.2 per cent) and fell to 16.4 per cent at the end of the study.

Asymptomatic carotid murmur: ultrasonic factors influencing outcome.

Sixty consecutive patients with an asymptomatic mid-cervical murmur on auscultation were identified amongst 1000 patients who underwent duplex scanning of the extracranial carotid arteries during 1981-83. They were classified according to the scan results into 12 high risk subjects with greater than 75 per cent stenosis of an internal carotid artery, 37 low risk subjects with a less than 75 per cent stenosis and 6 with no detectable stenosis. The mean duration of follow-up was 3 years (minimum 2 years) or until stroke or death. One was lost to follow-up and four were excluded having undergone carotid endarterectomy during the study. Six of twelve subjects with greater than 75 per cent stenosis suffered a stroke (five fatal and one non-fatal). There were no premonitory signs except in one patient with non-focal cerebral ischaemia for 2 months before an hemispheric stroke. There was one fatal stroke in the less than 75 per cent stenosis group and none in the control group. In all, 17 (28 per cent) patients died (myocardial infarction, 8; stroke, 6; malignant disease, 3). These results confirm that asymptomatic carotid murmurs are associated with increased mortality with most having non-severe carotid disease on duplex scanning and few strokes during follow-up. There is an important minority with tight carotid stenosis who carry a worrying risk of stroke if left untreated.

Duplex scanning and plaque histology in cerebral ischaemia.

Twenty-seven patients undergoing carotid endarterectomy (21 M, 6 F), with a mean age of 62 years, were studied by carotid ultrasound imaging, angiography, and histological examination of endarterectomy specimens, including Perl's stain to detect haemorrhage more than a week old. Haemorrhage into a plaque was seen histologically in 21 patients (78%), compared with 19 (70%) diagnosed preoperatively as echolucent heterogeneous plaques on ultrasound imaging. The remainder were echogenic homogeneous, fibrous plaques. In only one case was the nature of the plaque diagnosed by contrast arteriography. Excised endarterectomy specimens were inspected independently of the ultrasound assessment to determine whether the site of haemorrhage communicated with the base of an atherosclerotic ulcer. Communicating haemorrhages were present in 9 of 11 with episodic symptoms and non-communicating haemorrhages in 7 of 10 patients with a single cerebrovascular event. Perl's stain showed recent haemorrhage in 7 of 11 patients with multiple symptoms, and old haemorrhage in 9 of 10 patients with a single event. These findings suggest that ultrasonically heterogeneous communicating carotid plaques are symptomatically more active than homogeneous non-communicating plaques.

Does the in situ technique for autologous vein femoropopliteal bypass offer any hemodynamic advantage?

The improved patency rates that have been claimed for in situ femoropopliteal vein bypass have been attributed to improved hemodynamics because of the natural taper of the vein and maintenance of wall compliance because of preservation of the nutrient vasa vasorum. Blood flow in 31 in situ and 21 reversed vein grafts was measured noninvasively with a duplex ultrasound scanner at a median of 6 months after operation. There was no significant difference in the resting or hyperemic flows between the two groups (p much greater than 0.1). The compliance of 15 undisturbed and 15 fully mobilized in situ vein grafts was measured noninvasively by Doppler ultrasonography immediately after operation and at 3 months. There was a significant fall in compliance in both groups (p less than 0.001) but no significant difference between them (p much greater than 0.1). We have been unable to demonstrate any significant hemodynamic advantage with the in situ technique but believe that its use is still justified because of technically easier anastomoses and an improved utilization rate. Preservation of the vasa vasorum does not maintain wall compliance and complete mobilization of the vein relieves any uneven tension and ensures that all venous tributaries are ligated, removing the risk of arteriovenous fistulas.