Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EMBOLISM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources
PubMed1995

Changes in striatal dopamine metabolism after microsphere embolism in rats.

BACKGROUND AND PURPOSE: Dopamine plays an important role in striatal function. The present study was undertaken to elucidate the pathophysiological changes in striatal dopamine metabolism after microsphere embolism. METHODS: Microspheres (48 microns) were injected into the right internal carotid artery of rats. Extracellular levels of dopamine and its metabolites were measured by in vivo microdialysis with the aid of high-performance liquid chromatography. In vivo striatal tyrosine hydroxylation and turnover (catabolism) rate of dopamine were estimated on the first and third days after the embolism. These were estimated by measuring tissue dopa or dopamine content in the presence of either an aromatic L-amino acid decarboxylase inhibitor or a tyrosine hydroxylase inhibitor, respectively. RESULTS: In the microdialysis study, a 190-fold increase in the release of dopamine from the right striatum was observed 40 minutes after microsphere embolism, whereas the striatal dopamine metabolites decreased during the first 180 minutes after the embolism. Microsphere embolism decreased the striatal dopamine content throughout the experiment (28 days), whereas it increased tissue dopamine metabolites on the first day, followed by a decline in the metabolites on the third day or later. The in vivo turnover rate of dopamine decreased both on the first and third days, whereas the in vivo tyrosine hydroxylation decreased only on the third day after the embolism. CONCLUSIONS: The results suggest that microsphere embolism induces severe damage to striatal dopaminergic metabolism 3 to 28 days after the embolism. Dopamine synthesis may be more resistant to the embolism-induced ischemic insults than its catabolism.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1995

Incidence and frequency of cerebral embolic signals in patients with a similar bileaflet mechanical heart valve.

BACKGROUND AND PURPOSE: The aim of this study was to determine the incidence and frequency of cerebral embolic signals in a patient population with the same mechanical heart valve using transcranial Doppler examination. Furthermore, it aimed to identify patient and valve characteristics that correlated with the occurrence of these signals. METHODS: Ninety-two patients with Carbomedics valves and 15 healthy control subjects took part in the study. Thirty-six patients were examined before and immediately after valve implantation (group 1), 34 patients 1 year after surgery (group 2), and 22 patients 5 years after surgery (group 3). Cerebral embolic signals were detected using transcranial Doppler monitoring of the right middle cerebral artery. RESULTS: Asymptomatic cerebral embolic signals were detected in 87% of the total 92 patients, in 77.8% of group 1 patients, in 91.2% of group 2 patients, and in 95.5% of group 3 patients. No cerebral embolic signals were detected in group 1 patients before surgery or in control subjects. The incidence (P = .04) and frequency (P = .002) of cerebral embolic signals increased significantly with longer duration of valve implantation. A significant positive correlation was also found between frequency of cerebral embolic signals and valve size (r = .4326, P = .00001). Median frequency of embolic signals in patients with a history suggestive of cerebrovascular events (n = 14) was 60 signals per hour compared with 11 signals per hour in those with no such history (n = 42; P = .04). CONCLUSIONS: The incidence and frequency of cerebral embolic signals increased with the duration of valve implantation. The frequency of these signals also was dependent on valve size. Patients who had experienced cerebrovascular symptoms had a higher frequency of cerebral embolic signals compared with those with no such signals. These results should be interpreted with caution but suggest that this method could be of help in assessing the risk of stroke in prosthetic heart valve patients and that prospective clinical studies should now be carried out.

Adult↗
PubMed2003

Coil embolization of iliac artery aneurysms developing after abdominal aortic aneurysm repair with a conventional bifurcated graft.

PURPOSE: To evaluate the efficacy of embolizing iliac artery aneurysms (IAAs) developing after abdominal aortic aneurysm (AAA) repair. METHODS: The records of 6 patients (5 men; mean age 79 years, range 61-87) with unilateral (n=3) or bilateral (n=3) IAAs that had developed after AAA repair were reviewed. In all patients, the limbs of the bifurcated graft were anastomosed end-to-end or end-to-side with the external iliac arteries during AAA repair. Before embolization, superior mesenteric artery (SMA) arteriography was done in all patients to evaluate collateral pathways to the inferior mesenteric artery (IMA). RESULTS: The unilateral IAAs were treated by proximal and distal embolization. In 2 patients with bilateral IAAs, SMA angiography showed sufficient collateral flow to the IMA, so the aneurysms were treated by proximal embolization and packing. In the other bilateral IAA case, the left 6-cm IAA was treated by proximal and distal embolization, while the contralateral 3-cm IAA was not embolized because angiography demonstrated inadequate collateral flow to the IMA, indicating a possible risk of colon ischemia if both IAAs were embolized. Immediate postprocedural angiography in all patients showed complete exclusion of the IAAs. Mild buttock claudication occurred in 1 patient. There were no episodes of rupture over a mean 46-month follow-up. CONCLUSIONS: Embolization is a safe and effective alternative to open surgery for the treatment of IAAs that develop after AAA repair. However, before embolization, angiographic evaluation of collateral pathways to the IMA is essential to reduce the risk of colon ischemia.

Aged↗
PubMed2003

Embolization of spinal cord arteriovenous shunts: morphological and clinical follow-up and results--review of 69 consecutive cases.

OBJECTIVE: We sought to analyze the results of embolization in patients with intradural spinal cord arteriovenous shunts. METHODS: The clinical and radiological files of 69 of a population of 155 patients treated with embolization between 1981 and 1999 were reviewed retrospectively. The patients' clinical status was evaluated according to Karnofsky Performance Scale score. Twenty-one (14%) of 155 patients were treated surgically because they were thought to be poor candidates for embolization. Twenty-four (15%) of 155 patients were considered untreatable with surgery or embolization; in these patients, follow-up was proposed, but only 8 of them were followed appropriately and remained stable after the first consultation. Forty-one (26%) of 155 patients consulted our group, but no follow-up could be obtained. In 69 (45%) of 155 patients, comprising 20 children and 49 adults, endovascular treatment was performed with the patients under general anesthesia and without provocative tests, mainly with acrylic glue, in 99% of these patients. RESULTS: The mean number of diagnostic and therapeutic sessions was 3.5 per patient, and the mean number of pure therapeutic sessions was 1.5 per patient. Follow-up ranged between 6 months and 18 years (mean, 5.6 yr). In 16% of patients, anatomic obliteration of spinal cord arteriovenous shunts was obtained. Embolization reduced more than 50% of the spinal cord arteriovenous shunts in 86% of cases. No recanalization was noted on follow-up angiograms. Good clinical outcomes were obtained in 83% of the patients: 15% of them were asymptomatic, 43% were improved, and 25% were stable. In 4% of patients, embolization failed to stabilize the disease. Transient deficits were seen after embolization in 14% of the patients, and permanent severe complications occurred in 4% of the patients (Karnofsky Performance Scale score <or=70). Mild worsening was seen in 9% of the patients (Karnofsky Performance Scale score, 80). No bleeding or rebleeding was seen after endovascular treatment was considered to have been completed. CONCLUSION: This study proves that embolization with acrylic glue is a therapeutic option that compares favorably with surgery or embolization with other agents (particles, coils, or balloons). It offers stable long-term clinical results, despite not necessarily achieving total cure. Studies of larger series with longer follow-up are necessary to confirm these encouraging therapeutic data.

Adolescent↗
PubMed1984

Clinical and neuroradiological analysis of thrombotic and embolic cerebral infarction.

The clinical and neuroradiological characteristics of cerebral thrombosis and cerebral embolism were established in 109 cases with nonembolic and 120 cases with embolic arterial occlusion of the brain. Cases with cerebral thrombosis due to occlusion of perforating branches were excluded from the study, to equalize the size of the involved arteries in the two groups. More than 60% of patients with cerebral embolism showed a level of consciousness lower than stupor, while less than 15% did so in the thrombotic group. Cortical signs such as aphasia, agnosia, conjugate deviation, etc., were more frequently seen in the embolic group. A mean size of the infarct on CT (Infarct-Index) was significantly larger, and a shift of the midline structure was more frequently noticed in the embolic group than in the thrombotic group. Accordingly, the patients with cerebral embolism showed more unfavorable outcome than those with thrombosis. Hyperdense area developed in 40% of cerebral embolism during the period of observation, while in only 2% of cerebral thrombosis. Recurrence of the attack was very common in cerebral embolism. Forty-four percent experienced more than two episodes of cerebral and/or systemic embolization; of these recurrences 51% (27% of all cases) occurred within 2 weeks before and/or after the present episode that caused the admission. The importance of atrial fibrillation as the source of emboli was reemphasized.

Adolescent↗
PubMedDate not supplied

Rare forms of peripheral arterial embolism: review of 11 cases.

The purpose of this study was to present 11 patients operated on owing to rare forms of peripheral arterial embolism at the Institute for Cardiovascular Diseases of the Serbian Clinical Center over a period of 20 years. Three patients were operated on owing to a foreign body embolism, two owing to a septic embolism, three owing to emboli that originated from malignant tissues, two owing to an embolization from cardiac myxoma, and one owing to an embolism from a myxomatous atrial septal defect. The preoperative evaluation included clinical examination, laboratory findings, and electrocardiography; in the majority of cases, ultrasonography and angiography were performed. Surgical treatment included foreign body extraction in three cases; thromboembolectomy in seven cases, and artery resection and saphenous graft interposition in one patient with septic embolism. In addition, three cardiosurgical procedures were done: aortic valve replacement in the patient with a septic embolism and tumor excision in patients with atrial myxoma. In addition to the usual clinical signs of acute limb ischemia, in the rare forms of arterial embolism, the presence of certain uncommon clinical symptoms was also observed. The early results of vascular surgical treatment were very good in all patients. Further follow-up revealed a poor prognosis in patients with malignant arterial embolism.

Adult↗
PubMed1999

Comparison of fixation of the femoral component without cement and fixation with use of a bone-vacuum cementing technique for the prevention of fat embolism during total hip arthroplasty. A prospective, randomized clinical trial.

BACKGROUND: Acute hypotension, hypoxemia, cardiac arrest, and sudden death are well recognized complications during total hip arthroplasty, and they have been attributed to embolization of fat and bone marrow. An increase in intramedullary pressure in the femur is the most important pathogenic factor for the development of embolic events. Intravasation of fat, bone marrow, and bone debris during the implantation of a femoral component, and the embolization of these elements through the venous system located along the linea aspera and through the metaphyseal vessels, have been demonstrated experimentally and clinically. The purpose of the present study was to compare the effects of fixation of the femoral component without cement with those of fixation with a bone-vacuum cementing technique on the severity of embolic phenomena and cardiopulmonary impairment during total hip arthroplasty. Fixation with a conventional cementing technique was also evaluated as a control. METHODS: Sixty patients (sixty hips) were entered into a prospective, randomized clinical trial. The patients were assigned to one of three groups. Group 1 consisted of twenty patients who had the femoral component inserted without cement, Group 2 comprised twenty patients who had the component inserted with a conventional cementing technique, and Group 3 included twenty patients who had fixation with the so-called bone-vacuum cementing technique. In the hips in Group 3, a suction of -800 millibars (-80,000 pascals) was applied to a proximal drainage cannula placed along the linea aspera and a distal drainage cannula placed in the diaphysis in order to produce a vacuum in the medullary cavity of the femur during the application of cement and the insertion of the stem. Transesophageal echocardiography and hemodynamic and blood-gas analysis were performed during the operation. RESULTS: Severe embolic events (defined as a cascade of fine echogenic particles of less than five millimeters in diameter) were observed in seventeen (85 percent) of the twenty patients during insertion of the stem with use of a conventional cementing technique but in none of the patients who had the stem inserted without cement (p < 0.05). Insertion of the femoral component with the bone-vacuum cementing technique prevented embolic phenomena in all but one patient (5 percent). Arterial oxygen saturation decreased significantly (p < 0.05) from a mean of 99.5 to 92.9 percent after insertion of the stem with a conventional cementing technique, but only slight changes were observed in the patients who had fixation of the component without cement and in those who were managed with the bone-vacuum cementing technique. Intraoperative pulmonary shunt values increased a mean of 24 percent (p < 0.05) when the femoral component was inserted with a conventional cementing technique, but with the numbers available we did not detect a significant change in those values when the component was fixed without cement or when it was inserted with use of the bone-vacuum cementing technique. CONCLUSIONS: The present study showed that severe embolic events and intraoperative pulmonary impairment are common when a femoral component is fixed with use of a conventional cementing technique. The results clearly demonstrated a low risk of embolism during total hip arthroplasty when the femoral component was fixed without cement and when it was fixed with the bone-vacuum cementing technique. The ability of a patient to withstand an embolic event should be considered before fixation of the femoral component with use of a conventional cementing technique is planned.

Aged↗
PubMed2001

Surgical treatment of hemangioblastomas with presurgical endovascular embolization.

The usefulness of presurgical embolization of hemangioblastomas was evaluated retrospectively in eight of 30 operations performed on eight of 27 consecutive patients with histologically verified hemangioblastoma. All tumors had over 3.5 cm maximum diameter of the solid mass. Presurgical embolization achieved 100% embolization in one case, 95% to 80% in two, 70% to 50% in two, and less than 50% in three. Total obliteration was obtained only in one case with a single feeding artery. No permanent neurological deficits developed after embolization, but cerebellar infarction occurred in one patient. The surgery was definitely easier than expected in three cases with 80% or more obliteration of tumors. Tumor swelling and cerebellar hematoma occurred during operation in one case with 70% tumor embolization and another case with less than 50%. Blood transfusion during operation was carried out in two cases with less than 50% tumor embolization. The clinical outcome was good recovery in one case, moderate disability in five, and severe disability in two. The reasons for residual neurological deficits were operation and meningitis in one patient, operative and preoperative symptoms in two, and residual preoperative symptoms in four. Neurological deterioration after surgery occurred in three patients with tumor embolization of less than 50%. Partial embolization of hemangioblastomas does not reduce operative complications or morbidity, unless almost complete embolization is achieved, which is not so easy.

Adolescent↗
PubMed2006

Acute pulmonary embolism to the subsegmental level: diagnostic accuracy of three MRI techniques compared with 16-MDCT.

OBJECTIVE: The purpose of this study was to assess the individual and combined usefulness of MRI techniques in cases of acute pulmonary embolism and to compare the usefulness of these techniques with that of 16-MDCT. SUBJECTS AND METHODS: Sixty-two patients with symptoms indicating acute pulmonary embolism underwent an MRI protocol that progressed from real-time MRI through MR perfusion imaging to MR angiography. The results were compared with those of 16-MDCT, which was the reference standard. Thoracic incidental diagnoses other than pulmonary embolism also were sought with CT and MRI. RESULTS: Pulmonary embolism was diagnosed with CT in 19 patients for totals of 90 lobar, 245 segmental, and 434 subsegmental arteries. On a per-patient basis, the sensitivities of real-time MRI, MR angiography, MR perfusion imaging, and the combined protocol were 85%, 77%, 100%, and 100%, respectively. The specificities were 98%, 100%, 91%, and 93%. The kappa values in a comparison of the MR techniques with CT were 0.89, 0.87, 0.86, and 0.9. On a per-embolus basis, the sensitivities of real-time MRI, MR angiography, and MR perfusion imaging for lobar pulmonary embolism were 79%, 62%, and 100%. The sensitivities for segmental pulmonary embolism were 86%, 83%, and 97%, respectively. MR perfusion imaging had a sensitivity of 93% for subsegmental pulmonary embolism. Eight of nine incidental findings revealed on CT were also subsequently diagnosed with real-time MRI. MRI failed to reveal a case of emphysema. Mean MRI examination time was 9 minutes 56 seconds. CONCLUSION: The combined MR protocol is both reliable and sensitive in comparison with 16-MDCT in the diagnosis of pulmonary embolism. MR perfusion imaging is sensitive for the detection of pulmonary embolism, whereas real-time MR and MR angiography are specific.

Acute Disease↗
PubMed1992

Acute lower gastrointestinal hemorrhage: treatment by superselective embolization with polyvinyl alcohol particles.

OBJECTIVE: The major risk of transcatheter embolotherapy for acute hemorrhage in the lower gastrointestinal tract is irreversible intestinal ischemia. The authors studied the efficacy and safety of superselective transcatheter embolization with polyvinyl alcohol particles in arresting acute hemorrhage in the lower gastrointestinal tract. SUBJECTS AND METHODS: All patients with clinical or scintigraphic evidence of acute hemorrhage in the lower gastrointestinal tract were considered for superselective embolization. The nine patients with angiograms that showed active hemorrhage in the lower gastrointestinal tract underwent the procedure. Superselective embolization was done through a 3-French catheter and was accomplished by using 100- to 590-microns polyvinyl alcohol particles. The segments of the intestinal tracts involved in the embolizations were examined for the presence of ischemia by endoscopy (n = 7) or histologic evaluation of a surgical specimen (n = 2) 2-44 days (mean, 11 days) after embolization or by clinical evaluation (n = 1). RESULTS: The lesions treated by this method were located in the colon (n = 8) and jejunum (n = 1). Immediate hemostasis was achieved in every case. Three patients had recurrent lower gastrointestinal hemorrhage 1-24 days (mean, 9 days) after initial embolization. Two of these patients had surgery, while one had a successful second embolization. Two asymptomatic patients were found endoscopically to have small areas of ischemia involving only the mucosa. Only one patient was shown to have severe mucosal ischemia; this involved the colon in a distribution that suggested it was not caused by the embolization. CONCLUSION: Ten superselective embolization procedures that used polyvinyl alcohol particles successfully controlled hemorrhage in the lower gastrointestinal tract in nine patients. In no case was intestinal infarction induced by the procedure, and only two endoscopically proved cases of asymptomatic mucosal ischemia occurred.

Acute Disease↗
PubMed1993

Is bilateral lower extremity compression sonography useful and cost-effective in the evaluation of suspected pulmonary embolism?

OBJECTIVE: Because deep venous thrombosis is clinically linked with pulmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonograms when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmonary embolism and deep venous thrombosis. MATERIALS AND METHODS: Two hundred twenty-three consecutive patients with suspected pulmonary embolism had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography. RESULTS: In 75 cases, the results of ventilation-perfusion lung scanning indicated an indeterminate probability of pulmonary embolism. Evidence of thrombosis was seen on sonograms in 11 of these 75. In the remaining 64, 17 underwent pulmonary arteriography and four (24%) had pulmonary embolism. Findings on lung scans indicated a low probability of pulmonary embolism in 70 of 223 patients. Evidence of thrombosis was seen on sonograms in 11 of these 70. Five of the remaining 59 underwent pulmonary arteriography and one (20%) had pulmonary embolism. According to the 1993 Medicare Fee Schedule, if all 145 patients whose lung scans were nondiagnostic had sonography and only those with normal sonograms had pulmonary arteriography, the professional and hospital charges would be $359,552. If all 145 had pulmonary arteriography without sonography, the charges would be $395,031. CONCLUSION: If ventilation-perfusion lung scans indicate a low or an indeterminate probability of pulmonary embolism and bilateral lower extremity compression sonography is performed, only those patients with normal sonographic findings would need further study. Thus, 15% (22/145) of patients could be spared pulmonary arteriography, and the estimated savings in cost would be 9%.

Algorithms↗
PubMed1996

Acute pulmonary embolism: value of transthoracic and transesophageal echocardiography in comparison with helical CT.

OBJECTIVE: The goal of this study was to prospectively compare the accuracy of transthoracic and transesophageal B-mode and Doppler echocardiography with helical CT for detecting acute pulmonary embolism. SUBJECTS AND METHODS: Thirty-five consecutive patients underwent transthoracic and transesophageal echocardiography and contrast-enhanced helical CT. Echocardiographic examinations were analyzed for indirect criteria, including increased main pulmonary artery diameter, tricuspid regurgitation, and dilatation of the right ventricular cavity, as well as for direct thrombus visualization. Sensitivity, specificity, and negative and positive predictive values were calculated. RESULTS: Pulmonary embolism was revealed by helical CT in 22 of 35 patients; in 11 of these 22 cases, central pulmonary embolism was seen. Transthoracic and transesophageal B-mode echocardiography failed to reveal pulmonary embolism in nine patients, two of whom had central pulmonary embolism. The sensitivity and specificity of the combination of both echocardiographic investigations were 59% and 77% respectively (82% and 92% for central pulmonary embolism). In three patients, pulmonary embolism was diagnosed by direct clot detection with transesophageal echocardiography. In two patients, only the indirect parameters indicated pulmonary embolism. Overall indirect echocardiographic parameters were characterized by a low sensitivity that ranged from 50% for tricuspid regurgitation to 21% for main pulmonary artery diameter. CONCLUSION: In comparison with helical CT, transthoracic and transesophageal echocardiography had limited accuracy for detecting pulmonary embolism.

Acute Disease↗
PubMed2001

Doppler sonography of hepatic arterial blood flow velocity after percutaneous transhepatic portal vein embolization.

OBJECTIVE: This study was conducted to elucidate the changes in hepatic arterial blood flow after portal vein embolization. SUBJECTS AND METHODS: We prospectively measured the flow velocity and resistive index of the common, right, and left hepatic arteries, using Doppler sonography, in 21 patients who underwent embolization of the right portal vein. The measurements were performed before and 1, 3, 5, 7, and 14 days after embolization. We assessed the changes in liver volume with a volumetric study using CT. RESULTS: After embolization, flow velocity in the common hepatic artery increased significantly (p < 0.0001). Flow velocity in the right hepatic artery also increased significantly (p < 0.0001), with a significant decrease in resistive index (p < 0.0001). The flow velocity and resistive index of the left hepatic artery were unchanged. The increase in flow velocity in the right hepatic artery significantly correlated with that in the common hepatic artery (r = 0.514, p < 0.05). The calculated volume of the embolized right hepatic lobe significantly (p < 0.0001) decreased, from 685 +/- 32 cm(3) before embolization to 568 +/- 28 cm(3) after embolization. The atrophy rate of the right hepatic lobe significantly correlated with the increase in flow velocity in the right hepatic artery (r = 0.700, p < 0.0005). CONCLUSION: Portal vein embolization induces an increase in hepatic arterial blood flow velocity in the embolized hepatic segments, resulting from an increase in common hepatic arterial flow, but not from a steal phenomenon due to decreased hepatic arterial blood flow in the nonembolized hepatic segments. This observation may be explained by the simple mechanical effect of interposing a slower flowing stream (portal flow) in the path of a faster flowing stream (arterial flow).

Adult↗
PubMed2001

Internal iliac artery embolization before endovascular repair of abdominal aortic aneurysms: frequency, efficacy, and clinical results.

OBJECTIVE: The aim of our study was to assess the frequency, efficacy, and incidence of adverse effects of internal iliac artery embolization. MATERIALS AND METHODS: Of 343 patients examined for stent-graft repair, 147 were suitable for endovascular treatment. Fifty-five patients underwent preprocedural embolization of the internal iliac artery either unilaterally (46 patients) or bilaterally (nine patients). Successful embolization was assessed angiographically and with helical CT follow-up examinations. Colonic ischemia was ruled out clinically or colonoscopically. Buttock claudication, and sexual dysfunction in men, were evaluated through a questionnaire. RESULTS: Embolization of the internal iliac artery increased by 16% the percentage of patients for whom endovascular repair was suitable. After successful embolization in all patients, routine CT follow-up examinations after a mean time of 16.7 months showed no evidence of endoleaks related to retrograde perfusion via embolized internal iliac arteries. Nevertheless, in all patients who had undergone embolization, a primary endoleak was detected in 43.4% at the first postoperative CT examination. None of our patients had evidence of colonic ischemia. Clinical follow-up data of 46 patients were available. Of these patients, mild to severe new onset buttock claudication was found in 13 (36.1%) of 36 patients with unilateral, and in eight (80%) of 10 patients with bilateral, internal iliac artery embolization (p = 0.03). Five (25%) of 20 men had an erectile dysfunction after the procedure. CONCLUSION: Embolization of the internal iliac artery is a safe and efficient procedure that increases the applicability for endovascular repair of aortoiliac aneurysms. However, buttock claudication and erectile dysfunction are a drawback in a substantial number of patients.

Aged↗
PubMed1995

Interferon-alpha 2b, with or without prior hepatic artery embolization: clinical response and survival in mid-gut carcinoid patients. The Norwegian carcinoid study.

BACKGROUND: Mid-gut carcinoid tumours often present with liver metastases, and survival has then been less than 2 years in earlier reports. We have evaluated the effects of interferon therapy on clinical response and survival, with or without hepatic artery embolization in these patients. METHODS: In a prospective study 30 female and 12 male patients, aged 23 to 75 years, with mid-gut carcinoid tumours and liver metastases underwent surgery with removal of as much as possible of their primary tumour. If technically feasible, embolization of hepatic arteries was performed in the absence of contraindications. Seventeen patients were embolized, and all patients received interferon-alpha 2b treatment for 1 year. Response factors were computer tomography (CT) measurement of the largest liver metastasis and the 24-h urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA). After 12 months patients with objective response or stable disease either continued or withdrew from interferon therapy. Survival was estimated when all patients had been observed for at least 36 months. RESULTS: Nine patients reduced the dose, and five withdrew from interferon treatment owing to side-effects the 1st year. Three patients died. Fifteen patients (39%) showed objective response 12 months after inclusion. Cumulative 5-year survival estimated from inclusion was 37.5% in all 42 patients but 71.4% in those who continued interferon therapy. The difference in survival between the interferon-treated and those who withdrew from interferon therapy at 12 months was significant when embolization was corrected for in a Cox model (p < 0.0125). The seemingly increased survival in embolized versus non-embolized patients did not reach statistical significance (p = 0.07). CONCLUSION: Interferon induced an objective response in mid-gut carcinoid patients as judged by the 24-h urinary 5-HIAA excretion. Patients receiving continuous interferon therapy showed improved response and survival compared with patients who stopped the treatment. Regardless of medical therapy, more survivors and more responders, as evaluated from CT measurements, were found among the embolized patients than among the non-embolized. Embolization could, however, not be shown to have a significant effect on survival.

Carcinoid Tumor↗
PubMed1982

Embolization of cerebral arteriovenous malformations with bucrylate.

Forty-six patients with cerebral arteriovenous malformations (AVM's) were selected for embolization with bucrylate. These patients were assigned to three different groups. Group I consisted of 22 patients with nonresectable AVM's who were selected for embolization with a Silastic calibrated-leak ballon. In 16 or these patients, embolization was achieved, with partial obliteration of the AVM in 14 and complete obliteration in two. Five patients had subarachnoid hemorrhage caused by the balloon bursting and concomitant dissection of the feeding vessel. Four of these patients recovered completely and one died of a brain-stem hemorrhage. A permanent field defect was noted in five cases, and two patients had a transient mild neurological deficit. Group II consisted of 13 patients treated by intraoperative embolization. Complete obliteration by embolization was obtained in four cases, and complete surgical resection after embolization in five. Partial embolization with no surgical resection was achieved in five cases. Three of these patients had a permanent mild neurological deficit and two had transient deficits. There was no mortality in this group. Group III consisted of 11 patients treated by embolization with bucrylate using a new latex calibrated-leak balloon. This balloon has a higher malleability, and takes on the exact configuration of the feeder, with no risk of dissection. This balloon also permits delivery of the faster and larger injection of bucrylate to the arterial feeders of the AVM. Two AVM's were completely obliterated, and embolization was only partially successful in the other cases. Neurological complications consisted of incomplete field defects in two cases, slight memory loss in one case, and transient clumsiness of the arm and face in one case. Two patients have a catheter permanently glued in the malformation, with no neurological complication. There was no mortality in this group.

Adolescent↗
PubMed2000

Preoperative embolization of cerebral arteriovenous malformations with silk sutures: analysis and clinical correlation of complications revealed on computerized tomography scanning.

OBJECT: The aim of this study was to determine the incidence and clinical significance of complications related to preoperative embolization of cerebral arteriovenous malformations (AVMs) with silk sutures as documented on postprocedure computerized tomography (CT) scans. METHODS: The CT scans were obtained within 12 to 24 hours after 221 (96%) of 230 consecutive embolizations in 70 patients. These CT scans were evaluated for the presence of ischemia, infarction, hemorrhage, or contrast agent extravasation. Adverse patient outcomes were determined after each embolization and were correlated with CT findings. New abnormalities demonstrated on CT scans were also correlated with the Spetzler-Martin AVM grade, degree of arteriovenous shunting, and location. New abnormalities, the majority of them infarcts, resulted from 29 (13%) of 221 embolization procedures. In 11 (38%) of 29 cases of new CT findings, patients were asymptomatic, including 10 with new infarcts on CT scans. New neurological deficits occurred in 20 (8.7%) of 230 total embolization procedures in 19 patients, including one death. Permanent deficits occurred in nine patients (3.9% per embolization procedure, 12.8% per patient). Of the patients with new neurological deficits, 18 (90%) of 20 embolization procedures resulted in new abnormalities on CT scans. Two patients with new transient neurological deficits had no new findings on CT scans. Spetzler-Martin grade, AVM location, degree of arteriovenous shunting, and higher numbers of procedures were not statistically associated with a higher incidence of abnormalities on CT scans or new permanent neurological deficits. CONCLUSIONS: Silk sutures are an effective and relatively safe embolic agent. After brain AVM embolization with silk sutures, new abnormalities were found on CT scans obtained in one of eight procedures. When a new CT finding occurred, the patient had roughly equal chances of having no new symptoms, having new transient neurological deficits, or having new permanent neurological deficits.

Adult↗
PubMed2006

Intrinsically radiopaque iodine-containing polyvinyl alcohol as a liquid embolic agent: evaluation in experimental wide-necked aneurysms.

OBJECT: To evaluate iodine-containing polyvinyl alcohol (I-PVA) as a precipitating liquid embolic agent, implant characteristics--including radiopacity, setting behavior, and biocompatibility--were studied in an aneurysm model in swine. METHODS: Twelve broad-based carotid artery (CA) sidewall aneurysms were surgically constructed in six pigs. Iodine-containing polyvinyl alcohol dissolved in dimethyl sulfoxide (DMSO) was injected during temporary balloon occlusion bridging the aneurysm neck. Control angiography as well as multidetector row computerized tomography (CT) angiography was performed after 4 weeks. Harvested aneurysms were investigated histopathologically and by 3-tesla high-field magnetic resonance (MR) imaging. The mean degree of aneurysm occlusion achieved was 96%. In two aneurysms a minimal protrusion of I-PVA into the CA lumen was observed. During one embolization, leakage of the liquid embolic agent due to DMSO-induced damage of the microcatheter resulted in CA occlusion. Aneurysms embolized with I-PVA could be discriminated clearly from the parent artery on CT angiograms because there was no beam-hardening artifact. High-field MR imaging allowed a detailed depiction of the liquid embolic distribution within the aneurysm. Histologically, a mild to moderate inflammatory response was found in successfully embolized aneurysms, and the polymer mass was frequently covered by a membrane of fibroblasts and endothelial cells. CONCLUSIONS: Iodine-containing polyvinyl alcohol is a ready-to-use liquid embolic agent clearly visible under fluoroscopy; additives are not required. The setting behavior allows for controlled delivery in aneurysm cavities. Histological studies performed 4 weeks after embolization revealed no sign of toxic tissue response to the liquid embolic agent. Overall, I-PVA exhibits interesting implant characteristics in that radiopaque admixtures are not necessary, thus allowing for artifact-free evaluation of treated aneurysms by using CT and MR angiography.

Aneurysm↗