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Results for “Collateral Circulation”

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PubMed2000

Perfusion and functional anatomy of the splenic remnant supplied by short gastric vessels.

BACKGROUND: Surgeons have described many methods to preserve the injured spleen for the maintenance of host defence. The volume and the perfusion of remaining splenic tissue are important for better functional results. Imaging the functioning tissue with radionuclide provides information about the physiology of the concerning organ. METHODS: Thirty rats were separated into three groups: control, explorative laparotomy alone; partial splenectomy, upper part of the spleen supplied by short gastric vessels was preserved after partial resection; and devascularized spleen, the entire spleen was preserved after ligation of splenic artery. The size, functional anatomy, and perfusion status of splenic tissue were assessed by liver-spleen scintigraphy using radiolabeled heat denatured red blood cells. RESULTS: In the partial splenectomy group, splenic radioactivity count, spleen/liver ratio, and radionuclide uptake were mildly reduced, and found to be 87% (P = 0.012), 91% (P = 0.16), and 88% (P <0.001) of the normal spleen, respectively. The area of functional tissue in the upper splenic remnant was 51% (P <0.001) of the normal spleen. In the devascularized spleen group, the radioactivity count, the ratio, and the uptake were 38% (P <10(-6)), 36% (P <10(-6)), and 49% (P <10(-6)) of the normal spleen respectively. The area of functional tissue in the devascularized spleen was calculated as 47% (P <10(-6)) of the normal spleen. CONCLUSIONS: The collateral circulation is insufficient for proper function of the entire spleen after disconnection of the main arterial blood supply. The functional tissue is markedly impaired. On the other hand, the upper part of the spleen is remained well perfused via the short gastric vessels. The collateral circulation is satisfactory for this splenic tissue after reduction of its volume. That size splenic tissue seems to have satisfactory functional ability. Proper functional results mostly depend on the balance between the volume and blood supply of the remaining splenic tissue.

Animals↗

PubMed1983

Treatment of sequential bilateral germ cell tumors of the testis following interval retroperitoneal lymph node dissection.

Modification in lymphatic drainage following retroperitoneal lymph node dissection, such as a collateral circulation or lymph node and lymphatic vessel regeneration, was observed in 2 patients in whom a second tumor developed in the remaining testicle. Such alterations of the lymphatic system are difficult to evaluate for the possible presence of metastatic disease. The presence of extensive collateral circulation rules out lymph node dissection or radiation therapy as an appropriate treatment in these patients. A short course of systemic chemotherapy, regardless of the histological type of the second malignancy, seems to be the safest adjunctive treatment in such cases.

Adult↗

PubMed1995

Surgical treatment of childhood moyamoya disease--comparison of reconstructive surgery centered on the frontal region and the parietal region.

Indirect revascularization procedures centered on the parietal region, such as encephalo-myo-arterio-synangiosis (parietal synangiosis) and direct procedures centered on the frontal region using both the anterior and the posterior branches of the superficial temporal artery (STA), such as STA to middle cerebral artery anastomosis combined with encephalo-duro-arterio-myo-synangiosis (frontal anastomosis) were compared in childhood moyamoya disease patients. The parietal synangiosis group consisted of 10 sides in five patients, and the frontal anastomosis group consisted of 30 sides in 15 patients. The development of postoperative collateral circulation was assessed by external carotid angiography, the neurological outcome was monitored for 2 years after surgery, and the intelligence quotient (IQ) was measured at least 6 months after surgery. Frontal anastomosis achieved superior results compared to the parietal synangiosis assessed by development of collateral circulation, in particular to the orbitofrontal artery, the prefrontal artery, and the precentral artery (p < 0.01), and reduction in the incidence of ischemic attacks, such as transient ischemic attacks (p < 0.05). The mean IQ in the frontal anastomosis group was higher than that in the parietal synangiosis group. Vascular reconstruction centered on the frontal region utilizing both the anterior and posterior branches of the STA is more efficacious than only synangiosis centered on the parietal region.

Arteriovenous Anastomosis↗

PubMedDate not supplied

Selective shunting based on somatosensory evoked potential monitoring during carotid endarterectomy.

Somatosensory Evoked Potentials (SEPs), to median nerve stimulation, were continuously monitored in 58 patients undergoing carotid endarterectomy A first group of patients was shunted routinely; in a second group the shunt was selectively applied when inadequacy of collateral circulation was suspected based on stump pressure values and SEP changes. Both amplitude and latency modifications of SEPs occurred during surgery; however no post-operative neurological deficit was seen unless there was a complete flattening of cortical waves, even a transitory one. Inadequate collateral circulation and embolic ischemia affected SEPs differently. While the latter produced a disappearance of all cortical waves, the former led first to a progressive flattening of later cortical waves and then of N20 as well. For values of stump pressure ranging between 20 and 50 mmHg SEPs were unchanged in some patients and altered in others. These findings may explain the controversies existing about the usefulness of stump pressure for predicting tolerance to carotid clamping.

Aged↗

PubMedDate not supplied

Differential outcome to middle cerebral artery occlusion in spontaneously hypertensive stroke-prone rats (SHRSP) and Wistar Kyoto (WKY) rats.

Evidence was found for different outcomes to middle cerebral artery occlusion in the young genetically hypertensive stroke-prone rat (SHRSP) compared to sham operated controls and the Wistar Kyoto rat (WKY). Qualitatively and quantitatively different gross lesions marked by Evans blue-albumin, cortical atrophy, large areas of strikingly altered cortical histology, postoperative survival and motor behavioral deficits differentiate young SHRSP from sham operated controls and the normotensive WKY. We conclude that the limited focal lesion observed in normotensive and sham operated rats is primarily due to surgical trauma of exposing the vessel and passing the ligature deep to it. The grossly larger and qualitatively different lesion in the SHRSP is the result of an inadequate circulation provided by the dorsal cerebral arterial collaterals. Since the 5-6 week old SHRSP were only mildly hypertensive (systolic blood pressure 140 mm Hg), the inadequate collateral circulation appears to be related to either a genetic or acquired problem rather than being secondary to a vascular lesion of chronic hypertension.

Animals↗

PubMed1985

Neovascularization produced by angiotensin II.

Following vascular occlusion, development of collateral circulation occurs in at least two time-related phases: (1) the fast enhancement of the function of preexisting channels and (2) the slow formation of new vessels. Inasmuch as the renin-angiotensin system can act as a protective mechanism against local ischemia by activating preexisting collateral vessels, it is of interest to establish whether angiotensin II also produces stimulation of new vessel formation. Angiotensin II or cholecystokinin, an unrelated peptide, was incorporated in a slow-release formulation polyacrylamide gel and implanted in a pocket made in the rabbit cornea. Periodic examinations revealed that angiotensin II significantly stimulates new vessel formation; maximum values were attained in approximately 2 to 3 weeks. In contrast, cholecystokinin or polyacrylamide gel alone failed to stimulate any significant new vessel formation. Positive neovascularization was present in 85% of the total number of corneas implanted with angiotensin II, whereas 14% and 8% positive results were seen in the corneas implanted with either cholecystokinin or polyacrylamide gel alone, respectively. It is concluded that angiotensin II not only facilitates the activation of preexisting collateral vascular pathways but also has angiogenic properties and therefore could play an active role not only in the fast but also in the slow phase of the development of collateral circulation.

Acrylic Resins↗

PubMed1979

[Intracranial hemorrhage in autopsy cases with occlusion of the circle of Willis (author's transl)].

Seventeen autopsy cases with occlusion of the circle of Willis were examined clinicopathologically. These patients ranged in age from 8 years to 64 years and consisted of 6 males and 11 females. The following results were obtained. 1. Fresh and massive intracerebral hemorrhage was confirmed in 13 of 17 patients and cerebral infarct in 4 of 17 patients. 2. Among these 13 patients, massive hemorrhage was found in basal ganglia, thalamus and hypothalamus of 9 patients, and in thalamus, cerebral peduncle and midbrain of 4 patients. 3. Rupture of the dilated muscular-type arteries was noted in the thalamus and basal ganglia in 2 of 13 patients. Ruptured arteries with organization of the lumen were found in the old hemorrhagic foci in one of them. 4. Overgrown and dilated arteries, branching off from the circle of Willis, were confirmed in 11 patients. These arteries consisted of "perforating" arteries well developed as collateral circulation. 5. No ruture in these arteries of the subarachnoidal spaces was found in 11 patients. In one of them, a small saccular aneurysm was found. These findings strongly suggest that in patients with occlusion of the circle of Willis intracerebral rupture of overgrown "perforating" arteries as collateral circulation may be the main cause of intracranial hemorrhage and intracerebral hemorrhage due to rupture of the arteries may be repeated.

Adolescent↗

PubMed2002

[Mesenteric-cava shunt's results with autologous jugular vein graft in children with pre-sinusoidal portal hypertension].

UNLABELLED: Presinusoidal portal hypertension (PPH) in children evaluates without functional hepatic damage, and with the time, trends to compensate through the creation of spontaneous portosystemic shunts. Nevertheless, some patients suffer episodes of gastrointestinal bleeding (GIB) that because of its frequency or severity, force to propose the change of surgical treatment. AIM: To evaluate the results of the mesocaval shunt (MCS) with autologous jugular vein in children with PPH. MATERIAL AND METHODS: Among the 32 children with PPH treated in our Hospital in the last 7 years, 10 had episodes of GIB that forced to perform a surgical shunt. The types of shunt were distal splenorenal in 3 patients and mesocaval in 7. These 7 cases are the material of this study. The origin of the PPH was a cavernomatosis transformation of the portal vein in 6 cases and a congenital hepatic fibrosis in 1. Before the surgery the average number of episodes of GIB was 9 (range 2-15); all the patients needed transfusion of blood products and variceal sclerosis. In 2 cases a tamponade with the Sengtaken balloon was required and 5 patients were treated with somatostatin and propranolol. The Doppler ultrasounds revealed and intense hepatofugal collateral circulation in all the cases. RESULTS: The initial flow through the shunt was adequate in all the patients except one who required a percutaneous balloon dilatation. Only this patient has suffered an episode of GIB. The hyperesplenism signs disappeared or improved in all the seven cases and the collateral circulation was significantly reduced. The pressure in the splenic territory decreased around 50% in the 4 patients that was measured. There were no cases of encephalopasty and only one child with congenital hepatic fibrosis shows signs of mild hepatic disfunction. The medium follow up post-shunt is 32 months (range 8 m-6 years). CONCLUSIONS: The MCS prevents the GIB in the PPH not responsive to the conservative treatment; its effectiveness is related with an adequate permeability though the graft and at least in the cases with portal cavernomatosis (the most frequent in children) doesn't produce hepatic dysfunction. Doppler ultrasounds give a very precise information about the post-surgical situation and are an excellent method of follow up.

Child↗

PubMedDate not supplied

Different susceptibilities to cerebral infarction in spontaneously hypertensive (SHR) and normotensive Sprague-Dawley rats.

Rapid occlusion of the middle cerebral artery (MCA) was undertaken in 5-6 week old rats to determine whether or not the young spontaneously hypertensive rat (SHR) or the normotensive Sprague-Dawley rat (SD) is protected against cerebral infarction by collateral circulation. Rats were killed 3 days after MCA occlusion and administration of Evans blue. As compared to SD, the SHR had elevated blood pressure prior to MCA occlusion, large cortical infarcts marked with Evans blue, and motor deficits contralateral to the occluded MCA. SHR did not develop an adequate collateral circulation, but SD were protected from infarction by it. Because the cerebral lesions were in young spontaneously hypertensive rats living prior to the established form of hypertension, the increased susceptibility to infarction was not secondary to it. Since normotensive rats usually do not infarct after sudden MCA occlusion, the infarction trait may be linked to the mechanism causing elevated blood pressure in spontaneously hypertensive rats.

Animals↗

PubMed1990

Incidence of forearm and hand ischaemia related to radial artery cannulation in newborn infants.

We report the incidence of transient and permanent ischaemia of the forearm and hand caused by radial artery cannulation in a series of 98 newborn infants. Birth weight ranged from 550 to 3920 g (median 1600 g) and gestational age ranged from 26 to 40 weeks (median 31 weeks). In 4 of the 98 infants transient ischaemia of the forearm and/or hand occurred. In three infants the onset of ischaemia was probably related to thrombo-embolic events and in one infant to inadequate palmar collateral circulation. Permanent ischaemic damage with tissue loss did not occur in any infant. It is concluded that permanent ischaemic damage to the forearm and/or the hand with tissue loss, attributable to radial artery cannulation, is seldom encountered in newborn infants. In minimizing the risk of ischaemia, careful assessment of palmar collateral circulation prior to cannulation and of all factors predisposing to the onset of ischaemia is essential. Immediate removal of the catheter at the earliest signs of ischaemia, is essential to prevent ensuing tissue loss.

Catheterization, Peripheral↗

PubMed2002

Non-invasive investigation and management of aortic saddle embolus in a 7-month-old infant.

There are few reports in the literature on the ultrasound appearance of aortic saddle embolus, and none relating to small children. This unusual condition is usually diagnosed angiographically. The purpose of this report is to show how effectively high-frequency ultrasound can identify a saddle embolus with its associated collateral circulation in a young child, and to demonstrate its usefulness in monitoring the efficacy of treatment. In this case the embolus occurred as a complication of parvovirus B19 myocarditis and was diagnosed and followed up entirely by ultrasound examination, with no invasive procedure performed. The early development of an extensive collateral circulation prevented distal tissue necrosis and allowed a conservative approach to management.

Aortic Diseases↗

PubMed1987

Common carotid occlusion for unclippable carotid aneurysms: an old but still effective operation.

We present a selected series of nine patients with unclippable internal carotid artery aneurysms to illustrate our current approach to this problem. Eight of the nine underwent common carotid ligation after preoperative angiographic evaluation. Tolerance to carotid occlusion was determined intraoperatively by awake examination, electroencephalogram (EEG) monitoring, and carotid stump pressure measurements. No patient developed a permanent deficit; seven of eight treated aneurysms have thrombosed. Our experience and review of the literature indicate that most ischemic complications after carotid ligation seem to be thromboembolic, rather than due to "low flow" from poor collateral circulation. For this reason, we have gradually come to favor common carotid (CCA) over internal carotid (ICA) occlusion in many of these patients. After CCA occlusion, the ICA frequently remains open and embolic complications are therefore less likely. An extracranial-intracranial bypass procedure is performed only in those patients with poor collateral circulation demonstrated by cross compression angiographic studies, by the development of new deficits during test occlusion, or by the appearance of EEG changes during test occlusion. We suggest that CCA ligation remains a useful alternative in the management of unclippable internal carotid aneurysms.

Adult↗

PubMed1988

[Spinal claudication following ileocaval venous thrombosis].

The case is reported of a young male who presented with intermittent claudication after thrombosis of the right common femoral, iliac and caval vein. The symptoms were explained by the severe proximal venous obstruction. The patient, however, also complained of lumbar pain during and long after walking, and showed signs of irritation of nerve roots L4 to S1 on the right side. Venography and CT-scan disclosed venous collateral circulation leading through the spinal canal. The blood drained through the foramina intervertebralia to the caval vein, causing compression of the nerve roots depending on their filling. Thus, the claudication was "venous" in two ways, muscular (due to inadequate drainage) and spinal (due to intermittent compression of lumbar nerve roots by the collateral circulation).

Adult↗

PubMed1981

Frequency and clinical significance of failure to visualize the conus artery during coronary arteriography.

In patients with occlusion of the left anterior descending coronary artery (LAD) or right coronary artery (RCA), the conus artery, which arises at or near the origin of the RCA, often serves as a principal source of collateral circulation. Coronary arteriograms in 508 adult patients revealed that in 80.5% the conus artery was well visualized on the RCA angiogram, but that in 19.5% it was not adequately visualized due to injection of contrast distal to its origin. In the latter patients, the presence of conus-LAD or conus-RCA collaterals might therefore go undetected. Because the degree of distal filling via collateral circulation affects medical and surgical decisions, it is important to attempt to visualize the conus artery adequately whenever the LAD or RCA is obstructed.

Angiography↗

PubMed1988

[Cerebral circulation at rest and following CO2 stimulation in patients with unilateral carotid obstruction].

Using the 16-detector 133Xe-NaCl-technique (Novo Cerebrograph) quantitative measurements of regional cerebral blood flow (rCBF) were performed in 14 patients with unilateral carotis obstruction before and during stimulation with 3% CO2 inhalation. In all patients resting studies did not show any significant differences in hemispheric perfusion. In 11 patients the hemispheric blood flow increased significantly (by more than 6%) during CO2 inhalation on the side without carotis obstruction. The following results were found after 3% CO2-stimulation over the hemisphere with the obstructed carotid artery: 1) rCBF increased significantly on both sides (n = 6) indicating the sufficiency of cerebral collateral circulation; 2) a side-to-side significant difference (n = 4) with the lower perfusion on the pathological side, indicating a decreased or suspended reserve capacity; and 3) bilateral loss of cerebrovascular reactivity (n = 4) as indicator of insufficiency of cerebral collateral circulation. Asymmetry in rCBF or missing cerebrovascular reserve are indications for surgical treatment of the carotis obstruction.

Administration, Inhalation↗

PubMed1994

[Ultrasound in diagnostics of blood vessels: the role of the assessment of both extra- and intracranial flows by Doppler ultrasonography].

Ultrasound and Doppler phenomenon form the basis of the ultrasound diagnostics of blood vessels. They permit to visualize vessel walls and blood flow and to measure its velocity and direction. Thanks to these possibilities the new non-invasive techniques, faciliating the assessement of extra- and intracranial arteries and monitoring of collateral circulation in their severe lesions came into being. Extra- and intracranial blood flow in 405 patients was assessed by USG-D examination. It was impossible to conduct the examination of intracranial arteries in 40 patients, normal flow has been found; in 234 patients, in 30 patients disorders of vertebral-basal circulation were found, in 29 patients they were caused by lesions of intracranial arteries, and in 37 patients by lesions only in extracranial arteries. In 35 patients severe and disseminated vascular lesions were found the above observation was based on the assesement of both extra- and intracranial blood flow. The assessement also faciliated monitoring of collateral circulation.

Blood Vessels↗

PubMed1991

Acute arterial insufficiency of the male genitalia.

Three patients developed severe ischemia of the penis or scrotum from acute arterial occlusion. In one case, nonhealing ulceration of the glans developed after atheroembolism to the dorsal penile artery. One patient had penile ischemia after ligation of pelvic and femoral collateral circulation during repair of an aorto-bilateral-iliac artery aneurysm. A third patient had ischemia of the penis and scrotum from thromboembolism to the iliac arteries during repair of an aortoenteric fistula. Only seven patients have been described with acute arterial occlusion and severe ischemia of the male genitalia. A rare phenomenon because of rich collateral circulation, acute ischemia of the genitalia nevertheless must be recognized as a sign of severe vascular disease and a consequence of major arterial ligation or occlusion in the pelvis and groins.

Acute Disease↗

PubMed1988

Superficial temporal-middle cerebral artery bypass: clinical pre- and postoperative angiographic correlation.

Between 1974 and 1982, an anastomosis between a pedicle of the superficial temporal artery (STA) and a cortical branch of the middle cerebral artery (MCA) was performed in 163 carotid systems in 157 patients for internal carotid artery occlusion in whom postoperative angiograms were available for analysis. The angiographic opacification of the arterial system was correlated with the patient's preoperative neurological function and stroke in the follow-up period. From this analysis, the following observations were made: 1) 96% of bypasses were patent; 2) 80% of bypasses achieved a high or medium MCA filling score; 3) there was hypertrophy of the STA in 70% of the cases; 4) greater bypass filling occurred in hemispheres with nonvisualized preoperative collateral circulation than in those with readily visualized collateral flow; 5) a meaningful correlation between angiographically assessed postoperative bypass function and stroke rate was not possible because only four patients suffered an ipsilateral hemispheric stroke in the 8-year follow-up period; and 6) patients who were neurologically unstable before the procedure were at greatest risk for a stroke in the follow-up period. It is apparent that objective analysis of the effectiveness of an STA-MCA bypass, or any other form of extracranial bypass, must await the development of new diagnostic studies in which high-resolution three-dimensional quantification of cerebral blood flow is possible. These studies will necessarily be correlated with preoperative and follow-up clinical data.

Adult↗