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A case of Moya-Moya disease confirmed by cerebral angiography in a 10-year-old girl is reported. Hypertrophic collateral circulation is easily visualized by MRI. MR angiography very accurately demonstrated the vascular obstruction and the collateral circulation. As MR angiography is not invasive, it promises to become a valuable alternative to conventional angiography in the diagnosis of Moya-Moya.
BACKGROUND: Diabetic patients have been reported to have impaired coronary collateral vessel growth, although they have excessive neovascularization in the retina. HYPOTHESIS: This study was designed to compare coronary collateral circulation (CCC) in patients with proliferative diabetic retinopathy (PDR) with that in patients without DR. METHODS: Ninety diabetic patients with chronic total occlusion in at least one major epicardial coronary artery were enrolled in the study. Groups 1 and 2 consisted of 48 patients without DR and 42 patients with PDR, respectively. Coronary collateral circulation (CCC) was analyzed according to the Rentrop system. Each group was also divided into two subgroups according to poor and good CCC. Serum vascular endothelial growth factor (VEGF) levels were measured using the enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: The mean Rentrop collateral score was higher in Group 1 than in Group 2 (2.39 +/- 1.07 vs. 1.76 +/- 0.76, respectively, p < 0.001). When the two groups were compared with respect to poor and good CCC, poor CCC was higher in patients with PDR (64 vs. 36%, respectively, p = 0.01). Serum VEGF levels were higher in patients with PDR than in those without DR (219 +/- 99 vs. 139 +/- 98 pg/ml, p < 0.001); however, patients with poor and good CCC had similar VEGF levels. CONCLUSIONS: We have shown that patients with PDR have a lower coronary collateral score than patients without DR. Also, serum VEGF was significantly higher in patients with PDR than in those without DR. These findings have suggested that diabetes mellitus may have a different action on retinal and coronary circulation.
PURPOSE: Intermittent pneumatic foot compression (IPC(foot)) augments arterial leg inflow. It has been suggested that prolonged use of impulse leg compression at home might ameliorate claudication caused by peripheral vascular disease by improving collateral circulation. The purpose of this study was to determine the effect of IPC(foot) treatment on claudication distance and arterial hemodynamics in patients with intermittent claudication caused by peripheral vascular disease. METHODS: Thirty-seven patients with stable intermittent claudication were admitted to this prospective controlled study. Of these, 25 patients received IPC(foot) (>4 hr/d) for 4.5 months (group 1), and the other 12 patients acted as control patients (group 2). Both groups were advised to exercise unsupervised for a minimum of 1 hour daily and received aspirin (75 mg/d). Groups were matched for age, sex, risk factors, claudication distances, and ankle pressures at baseline. In each patient, initial claudication distance (ICD), absolute claudication distance (ACD), resting ankle brachial index (r-ABI), ankle brachial pressure index after exercise (p-eABI), and popliteal artery volume flow were measured at day 0, 2 weeks, and 1, 2, 3, and 4.5 months. On completion of the treatment period (4.5 months), both groups continued with aspirin (75 mg/d) and unsupervised exercise and were re-examined after 12 months. Data analysis is based on nonparametric statistics, the Wilcoxon signed ranks test, and the Mann-Whitney test for intragroup and intergroup comparisons, respectively. Results are expressed as median and interquartile ranges. RESULTS: Over the 4.5 months of active treatment, (1) median ICD in group 1 increased by 146% (P <.001), from 78 m (interquartile range, 65-102 m) at baseline to 191.5 m (interquartile range, 127-254 m); ICD did not significantly increase in group 2; (2) median ACD in group 1 improved by 106% (P <.001), from 124 m (interquartile range, 100-160 m) to 255 m (interquartile range, 149-398 m); no significant changes were documented in group 2; (3) median r-ABI in group 1 rose by 18% (P <.001), from 0.57 (interquartile range, 0.48-0.62) to 0.67 (interquartile range, 0.64-0.70); no improvement was noted in group 2; (4) median p-eABI in group 1 rose by 110% (P <.001), from 0.21 (interquartile range, 0.07-0.27) to 0.44 (interquartile range, 0. 36-0.52); no changes were noted in group 2; and (5) median popliteal artery volume flow in group 1 improved by 36% (P <.001), from 100 mL/min (interquartile range, 59-163 mL/min) to 136 mL/min (interquartile range, 99.5-173.4 mL/min); no significant changes were found in group 2. At 4.5 months, ICD, ACD, r-ABI, and p-eABI in group 1 were all significantly better than those in group 2 (P <.01). Twelve months' posttreatment, walking ability and ABIs in group 1 were not statistically different from those at 4.5 months and remained significantly better than those of control subjects. CONCLUSION: Intermittent pneumatic foot compression used at home for 4.5 months increases claudication distance by over 100%. Associated increases in r-ABI by 18%, p-eABI by 110%, and arterial calf inflow by 36% suggest an improved collateral circulation. Maximum benefit seems to be offered over the initial 3 months. Treatment benefits are maintained 1 year after treatment. A multicenter study is indicated to quantify actual benefits and to demonstrate cost effectiveness.
STUDY DESIGN: A prospective study using magnetic resonance angiography (MRA) on a consecutive cohort of patients with cervical spine injuries. OBJECTIVE: To investigate clinical and radiographic features of vertebral artery injury/occlusion associated with nonpenetrating cervical spine trauma. SUMMARY OF BACKGROUND DATA: With the popularization of MRA, vertebral artery injury has been a common complication of cervical spine trauma. However, detailed clinical features such as restoration of blood flow in occluded vessels and collateral circulation have not been fully evaluated. METHODS: During a 2-year period, 64 consecutive patients with cervical spine fractures and/or dislocations were prospectively evaluated for patency of the vertebral artery and collateral circulation. Extracranial and intracranial MRAs were conducted at initial injury and follow-up. RESULTS: Vertebral artery occlusion occurred in 11 patients, including 10 with unilateral and 1 with bilateral. Only the patient with bilateral occlusion was symptomatic but had no permanent neurologic deficit as a result of brain ischemia. He had complete circle of Willis, which provides sufficient collateral blood supply from anterior circulation. Follow-up MRAs revealed restoration of blood flow in occluded vessel(s) in 3 patients. All of them had compressive injuries. CONCLUSIONS: The incidence of traumatically induced vertebral artery occlusion was 17.2%. The potential for blood flow restoration was higher in compressive injuries than in distractive injuries. The mechanism of occlusion in compressive injuries is likely to be vasospasm or minor artery dissection, which may cause reversible occlusion because vessels are subjected to relatively minor stretching in compressive injuries. Vertebral artery occlusion was rarely symptomatic because of sufficient collateral blood supply through not only contralateral vertebral artery but also the circle of Willis.
PURPOSE: The aim of this study was to evaluate color Doppler ultrasonography in assessing hand collateral circulation before radial artery harvesting for coronary artery bypass grafting. MATERIALS AND METHODS: The hand circulation of 30 patients scheduled for coronary artery bypass grafting was assessed by means of the modified Allen test and Doppler ultrasonography dynamic test. The test was performed by recording the flow in the superficial palmar branch of the radial and ulnar arteries with and without compression of the radial artery. In the postoperative period hemodynamic changes in the ulnar artery were also detected by means of Doppler ultrasonography. RESULTS: Among the 30 patients, one had abnormal and the other 29 had normal Doppler ultrasonography dynamic test results. All the patients' modified Allen test results were also normal. In 14 patients radial artery graft was used in the coronary artery bypass operation. CONCLUSION: Doppler ultrasonography dynamic test is an effective and noninvasive method in the preoperative evaluation of the hand collateral circulation for the safe removal of a radial artery graft.
Sixty-four patients with unilateral atherosclerotic occlusion of the internal carotid artery were studied at the Bakulev Institute for Cardiovascular Surgery with transcranial Doppler (TCD) ultrasonography and angiography before and after extracranial-intracranial arterial bypass (EIAB). TCD assessed accurately the extent of the collateral circulation in 95% of cases. The haemodynamic effectiveness of EIAB depends on the preoperative state of the collateral circulation; the greatest effect was achieved in patients with the lowest levels. EIABs improved the outcome in patients in the present series; hence vascular and neurosurgeons may be persuaded of the benefit of this treatment in patients with unilateral atherosclerotic occlusion of the internal carotid artery.
We report here an experience with five patients, aged 58 to 70, suffering gangrene of the left colon after spontaneous inferior mesenteric artery occlusion. All cases were the result of arteriosclerosis; in two, small aortic aneurysms were present and might have been responsible for emboli to the inferior mesenteric artery. The dead bowel was resected in all patients; three patients survived. No primary anastomoses were done and they are not recommended. Because ligation of the patent inferior mesenteric artery has been done so often without ill effects during aortic surgery, the collateral circulation to the left colon can be considered excellent. Gangrene is therefore rare and requires major interference with collateral circulation by emboli or arteriosclerotic occlusion. The clinical symptoms and signs may be confusing.
We present 7 cases of false intracavernous carotid artery aneurysms. Four occurred after trauma and three were caused iatrogenically. Two of the latter occurred in patients with pituitary adenomas, one after transsphenoidal microsurgery and the other after yttrium [YI90] seed implantation into the sella. The third iatrogenic aneurysm was seen shortly after transcavernous tumour surgery. In five of our seven patients massive, delayed, life-threatening epistaxis was the leading symptom. All traumatic cases were associated with immediate unilateral blindness or blurred vision and with skull base fractures. One of these had a concomitant carotid cavernous fistula. Treatment of choice of our 5 recent cases was permanent balloon occlusion of the intracavernous carotid artery at the level of the lesion. Collateral circulation was evaluated prior to definitive carotid occlusion using a balloon test occlusion. During the balloon test adequate collateral circulation was defined as symmetric angiographic filling of both hemispheres. Awake patients were neurologically examined continuously. In unconscious patients transcranial Doppler sonography, electroencephalographic and somatosensory evoked potential monitoring was used in addition. Intra-operative heparin administration was not reversed with protamin. A postoperative continuous heparin infusion was not found necessary. In our two early cases this technique was not available: In the first case we accomplished aneurysm occlusion by a surgically introduced Fogarty balloon catheter. Our second patient needed surgical trapping of the involved carotid after early unsuccessful attempts of selective aneurysm occlusion. After treatment no further epistaxis occurred. Follow-up angiography showed persistent aneurysm occlusion. The results were excellent in 5 cases and good in 1 case. One patient with bilateral lesions suffered a stroke after occlusion of the second, remaining carotid artery, despite functioning bilateral extra-intracranial bypasses. Four years later there is a mild dysphasia still present in this patient. The mean follow-up time was 75.6 months.
BACKGROUND: Hepatic artery thrombosis is one of the serious complications after liver transplantation. It will mostly cause a failure of the transplantation. This case of hepatic artery thrombosis showed a stable clinical course and minimal histological change, and now has been surviving for 4 years with normal liver function. We investigated the possible causes for asymptomatic hepatic artery thrombosis in one patient after orthotopic liver transplantation (OLT) and discussed the diagnosis of ischemia of OLT pathologically and clinically. METHODS: Liver function test, color Doppler ultrasonography, and hepatic arteriography were performed during the development of hepatic arteriothrombosis. Possible factors for the asymptomatic process of the thrombosis were analyzed. RESULTS: On the 4th postoperative day, thrombosis formed at the anastomotic stoma of the hepatic artery, and on the 11th postoperative day, the artery was completely occluded. Serial liver biopsies revealed intrahepatic cholestasis, hydropic degeneration of hepatocytes, atrophy of the biliary epithelium, and fibrosis in the portal area. Monitoring of liver function showed nothing abnormal except elevation of gamma-GT and ALP levels. On the 71st day after OLT, arteriography demonstrated that the hepatic artery remained completely occluded in addition to the establishment of collateral circulation and compensation of the portal vein. The patient didn't show any symptoms of arterial thrombosis. CONCLUSION: Collateral circulation and compensation of the portal vein are beneficial to allograft survival and avoidance of retransplantation after thrombosis of the hepatic artery. Color Doppler ultrasonography within 2 weeks after OLT is helpful to the early diagnosis of hepatic arteriothrombosis.
Cerebral vascular insufficiency due to occlusive lesions regarded as inaccessible is a common problem. The degree of cerebral dysfunction associated with such lesions is dependent in part on the amount of collateral circulation present. By anastomosing the superficial temporal artery to a branch of the middle cerebral artery an increase in collateral circulation is provided to the affected hemisphere. This report describes the results of twenty such procedures. Postoperative angiography demonstrates a 90% patency rate. There is frequent neurological improvement following surgery, and the rate of new TIA's or strokes seems less than would be expected. The most damaging complication of the procedure ist intracerebral haemorrhage. The indications for, and the complications of, such procedures are discussed.
Increase in portal venous pressure after anatomical or functional obstruction of portal venous system represents the most important complication of liver cirrhosis. Important sequels of portal hypertension are not dependable of etiology of liver disease. They are: increased collateral circulation in portal system and low pressure venous system (esophageal and gastric varices, portal hypertensive gastropathy and colopathy, hemorrhoids, collateral circulation through anterior abdominal wall, increased lymphatic flow, ascites, splenomegaly with occasional hypersplenismus, hepatic encephalopathy, hepatorenal syndrome.
Ultrasonic dopplerography and rheoencephalography were employed to investigate cerebral circulation in patients (n-123) with carotid artery atherosclerosis having transient disturbances of cerebral circulation or ischemic apoplexy. The ischemic foci were measured and localized at computed and NMR tomography. The above complex of examinations allowed evaluation of local, regional and overall blood filling of the brain, of collateral flow as well as conclusion on the type of cerebral hemodynamics. Focal lesions seem to arise in inadequate functioning of collateral circulation, that is in patients with unstable and decompensated hemodynamics. Active collateral circulation shown by the absence of noticeable interhemispheric asymmetry proved prognostically favourable. Administration of vasoactive drugs to patients with decompensated cerebral hemodynamics may induce stealing syndrome and aggravation of neurological symptoms.
HDDVI is a form of surgical treatment which, using a series of selective ligatures, is aimed at curing deep venous insufficiency due to valve absence. There are two fundamental principles: an incompetent vein ensures no venous return in standing position and is the site of reverse circulation; this ineffective vein develops a collateral circulation because of the increased pressure which it produces. However, this parallel circulation is in fact neutralised by the diseased vein which forms a retrograde shunt. Section ligatures are suggested taking into account single main veins with minimal collaterals (popliteal vein, femoral vein, external iliac vein) for which patency is essential. This novel theory is based upon physical, and anatomical and functional clinical arguments. The strategy is discussed in terms of the hemodynamic map of the deep veins obtained by orthostatic duplex Doppler. Confirmation that the theory is well-founded appears to be provided by the first cases treated.
Five patients with internal carotid artery occlusion were studied with MR imaging at 0.22 T. At the carotid siphon, occluded vessels showed absence of flow void in three patients. But two cases had "partial flow void" which mimicked small arterial caliber. In these patients angiography showed collateral circulation to the carotid siphon. So the partial flow void in the carotid siphon suggested internal carotid artery occlusion with collateral circulation.
To make an animal model of portal high blood flow, a retrograde portacaval shunt (PCS) was designed. A regular side-to-side PCS with large stoma was performed first, followed by the ligation of the vena cava just proximal to the anastomosis. Thus the whole amount of blood of the lower half body turned its flow into the portal system. Portal hypervolemic model was made in 11 dogs, The portal hemodynamics was studied by duplex before operation and 10 days, 20 days and 4 months after operation. In the 10th day the 20th day and the 4th month after operation, laparotomy was done again for observing FPP, portal collateral circulation, and liver biopsy. The portal high flow state was maintained constantly and FPP elevated in different degrees. The portal collateral circulation and the pathological change of the liver was not remarkable. The function of the liver was not damaged. The portal high flow state was proved not to cause real clinical portal hypertension, while the elevation of portal resistance was the important initiating factor for formation of portal hypertension.
A rare case, 32-year-old man, of cerebellar infarction with the occurrence of the 8th cranial nerve symptoms was reported. On the neuro-otological examination, hearing test and caloric test showed a severe hearing loss and no response on the right side, respectively, and the spontaneous horizontal nystagmus fixed to the left direction was observed. Magnetic resonance (MR) imaging showed the infarctions in the areas of anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA) on the right side. On the 14th illness day, the 8th cranial nerve symptoms disappeared, and on the 12th illness day, right hearing level and caloric response were significantly improved. We suggested that such an early recovery of the subjective symptoms and neuro-otological findings may be attributable to the recanalized circulation disturbance or the development of collateral circulation.
OBJECTIVE: To present our experience with permanent preoperative balloon occlusion of the internal carotid artery while dealing with different abnormalities of the lateral skull base and a comparison with the results mentioned in the literature. STUDY DESIGN: Retrospective case review. SETTING: Private neurotologic and skull base tertiary referral center. PATIENTS: Fifteen patients who underwent preoperative balloon occlusion of the internal carotid artery and surgery subsequently for various abnormalities of the lateral skull base between 1989 and 2002. INTERVENTIONS: Each patient was subjected to four-vessel angiography along with the manual cross-compression test and balloon test occlusion to assess the efficacy of the collateral circulation. After angiography, each patient underwent a preoperative balloon occlusion, after which a lateral skull base procedure was performed for removal of the abnormality. MAIN OUTCOME MEASURES: Only those patients showing evidence of adequate collateral cerebral circulation and a less than 1-second delay between the angiographic phases of the two cerebral hemispheres on angiography were considered fit for preoperative balloon occlusion. While under going the preoperative balloon occlusion, the patients were clinically assessed for the development of any neurologic symptoms and signs. Long-term follow-up after surgery was also based on the development of symptoms and signs of neurovascular compromise. RESULTS: A major complication in the form of long-lasting hemiplegia occurred in one patient (6.7%). This complication was the result of technical factors rather than an effect of cerebral ischemia, because it was caused by an intimal dissection produced by the catheter. A defect in the visual field occurred in one patient (6.7%) that resolved partially after antiplatelet therapy. There was no mortality in our series related to preoperative balloon occlusion of the internal carotid artery. CONCLUSION: Preoperative balloon occlusion of the internal carotid artery can still be considered a viable option for the management of the internal carotid artery during lateral skull base surgery. Proper preoperative evaluation of the adequacy and efficacy of the collateral cerebral circulation reduces the chances of postoperative neurovascular complications.
A new sign of arteriographic bleeding, diastolic clearance of angiographic contrast medium selectively from the bleeding vessel, is described. The use of this sign must be confined to rapidly bleeding end-vessel distributions or when nonopacified collateral circulation is not a consideration. It should not be confused with the normal washout of contrast substance in areas of multiple parent vessel collateral circulation where intermittent opacification is a normal feature.