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Biomedical subjects

N Hashimoto

Publications and source records attributed to N Hashimoto.

At least 307 records · Page 17Linked to original sources
PubMed1997

Cerebral aneurysms arising at nonbranching sites. An experimental Study.

BACKGROUND AND PURPOSE: The origin and pathogenesis of cerebral aneurysms arising at nonbranching sites are not clear. Using our animal model to induce cerebral aneurysms in rats, we examined induced aneurysms that developed at nonbranching sites. METHODS: In 35 Sprague-Dawley rats, the left common carotid artery was ligated and renal hypertension was produced to induce cerebral aneurysms. Twelve months later, the circle of Willis was carefully examined under a dissecting microscope. RESULTS: Other than cerebral aneurysms at branching sites of the circle of Willis, aneurysmal bulges developing at nonbranching sites were found in the proximal portion of the posteriorice rebral artery (P1) on the side of carotid ligation, which supposedly acted as a major collateral pathway after the ligation, in 19 of 35 treated rats. A total of 30 lesions were found in these 19 rats, and they were classified into fusiform aneurysms (22 lesions) involving the entire vessel wall for a short distance and saccular aneurysms (8 lesions) involving only a part of the wall and expanding laterally from the vessel wall. These P1s became larger in caliber and more tortuous after ligation. Aneurysms developed more frequently in proportion to these changes in these vessels. Moreover, most aneurysms in these vessels developed at or near the curvatures. All of the lateral aneurysms were found on the lateral wall of the curvatures of the vessels. CONCLUSIONS: The present findings indicate that cerebral aneurysms at nonbranching sites and saccular aneurysms at branching sites can occur under the same etiologic conditions. The site of origin is strongly related to hemodynamic stress.

Animals↗
PubMed1997

SCID-bg mice as xenograft recipients.

SCID-bg (scid/scid, beige/beige) is a strain of double-mutant mice with impaired lymphoid development and reduced natural killer (NK) cell activity. The present study was undertaken to evaluate the usefulness of SCID-bg mice as xenograft recipients. Fetal guinea pig tissues (liver, thymus, spleen) were transplanted under the kidney capsule of the mice and their serum guinea pig IgG levels were measured weekly thereafter, C.B.-17-scid and anti-asialo GM1 antiserum-treated (NK-depleted) C.B.-17-scid (C.B.-17-scid-AGM1) mice that received the identical transplants were used as controls. Throughout the experimental period (1, 2, and 3 weeks after transplantation), the average serum guinea pig IgG concentrations was highest in C.B.-17-scid-AGM1 mice followed by SCID-bg mice and lowest in C.B.-17-scid mice without antiserum treatment, though we could not find any statistical significance among these groups. However, SCID-bg mice always showed the smallest within-group variance (individual difference) in the serum guinea pig IgG concentrations (P < 0.05, versus C.B.-17-scid-AGM1 mice at 1, 2, and 3 weeks and versus C.B.-17-scid mice at 2 weeks). The graft size was not significantly different among these three groups, but the spleen grafts in C.B.-17-scid mice contained fewer nucleate cells than the other two groups. These results indicate that the reduced NK cell activity by beige mutation is not crucial for the success of xenogenic transplantation, though SCID-bg mice may be useful as xenograft recipients with a consistent potential to retain the viability and function of engrafted tissues.

Animals↗
PubMed1997

A case of nonfunctioning pituitary adenoma resembling so-called silent corticotroph adenoma.

It has been indicated that some subsets of clinically nonfunctioning pituitary adenoma exhibit immunohistochemical and ultrastructural features of somatotroph or corticotroph cells, which are described as silent somatotroph and corticotroph adenomas, respectively. We here describe a 70-year-old woman with nonfunctioning pituitary adenoma presenting with visual disturbance. None of the pituitary hormones show abnormal finding. Magnetic resonance imaging study revealed a pituitary tumor which developed inferiorly into the sphenoidal sinus. Tumor resection was performed by a transsphenoidal approach, and resulted in a partial resection of the tumor. The specimen indicated chromophobic adenoma. Immunohistochemical examination revealed a characteristic distribution pattern of cytokeratin staining for ACTH cell adenoma, although immunostaining for ACTH was only weakly positive. After the operation, only ACTH secretion was impaired, requiring replacement therapy with glucocorticoid. Bromocriptine was administered in order to prevent the recurrence of the tumor. It remains to be elucidated whether the present case could be classified as silent corticotroph adenoma, which was originally indicated to have aggressive characteristics, i.e., progressive visual defect, high incidence of infarction and frequent recurrence.

Adenoma, Chromophobe↗
PubMed1997

Hemodynamic and metabolic disturbances in patients with intracranial dural arteriovenous fistulas: positron emission tomography evaluation before and after treatment.

In patients with intracranial dural arteriovenous fistulas (AVFs), clinical symptoms and angiographic findings vary. The relevance of disturbed venous drainage to clinical symptoms and prognosis has been recognized. However, the roles of cerebral hemodynamics and metabolism, which are impaired by shunt flow or disturbed venous drainage, have not been fully evaluated. The authors studied the cerebral hemodynamic and metabolic status in 10 patients with intracranial dural AVFs using positron emission tomography (PET) scanning. Ten patients with dural AVFs underwent a PET study before treatment. The regional cerebral blood flow (rCBF), regional oxygen extraction fraction (rOEF), regional cerebral metabolic rate of oxygen (rCMRO2), and regional cerebral blood volume (rCBV) were measured using the 15O-labeled gas inhalation steady-state method The PET parameters that were obtained were analyzed and compared with the patients' neurological and angiographic findings. In six of the 10 patients, a PET study was also performed after treatment. Before treatments, all four patients with cerebral symptoms showed a severe reduction in rCBF and a mild elevation in the rOEF. The areas showing reduced rCBF corresponded with areas in which retrograde venous drainage into the cortical veins and delayed parenchymal circulation were seen on angiograms. In another two patients with occlusion of the affected sinus and/or retrograde drainage into the cortical veins, mild abnormalities were demonstrated in rCBF mapping. In the remaining four patients, all PET parameters except rCBV were within normal limits and venous flow was not impaired on the angiograms. In four patients who underwent surgical excision or transvenous embolization of the affected sinus, the cerebral hemodynamics and metabolism were improved, as were the clinical symptoms. In two patients who underwent transarterial embolization of the feeding vessels only or craniotomy, no hemodynamic improvement was achieved. Our results indicate that hemodynamic insufficiency detected by the PET study corresponded well with cerebral symptoms and angiographic findings of retrograde venous drainage into the cortical veins and delayed parenchymal circulation, but not with sinus occlusion or arterial blood supply. Eradication or prevention of retrograde venous drainage from the affected sinus into the cortical veins should be a treatment goal in patients with dural AVFs.

Aged↗
PubMed1997

Resection of a large, high-flow arteriovenous malformation during hypotension and hypothermia induced by a percutaneous cardiopulmonary support system. Case report.

The key to successful surgical resection of cerebral arteriovenous malformations (AVMs) is control of bleeding and cerebral swelling. Induced hypotension is one of the most valuable means of achieving this control. The authors introduced induced hypotension with mild hypothermia by using a percutaneous cardiopulmonary support system (PCPS) to resect a large, high-flow AVM. The efficacy and technical points of this method are discussed. The PCPS, whose entire intraluminal surface was coated with heparin, was established through a transfemoral route. During resection of the AVM, a mean arterial blood pressure of 60 mm Hg and a mean body temperature of 30 degrees C were easily maintained by regulating the flow rate of the PCPS and by blood cooling. The activated coagulation time was maintained at approximately 250 seconds with a minimum systemic administration of heparin. The authors report the case of a 30-year-old woman who presented with intraventricular hemorrhage and was diagnosed as having a large, high-flow AVM located in the left sylvian fissure. The AVM was fed by the left middle, posterior, and anterior cerebral arteries and drained by the many cortical ascending veins and the basal vein. The patient underwent surgery after hypotension and hypothermia had been induced via the PCPS method. Induced hypotension decreased the tension of the nidus and made its dissection easier. The AVM was totally resected and no hemostatic difficulties were encountered. On the basis of the authors' experience, they suggest that hypotension and hypothermia induced by using the PCPS is a powerful tool for the successful resection of large, high-flow AVMs.

Adult↗
PubMed1997

[Detection of microemboli in patients with extracranial carotid artery stenosis by transcranial Doppler sonography].

Embolism from a stenotic lesion of the extracranial internal carotid artery (ICS) is considered to be an important pathomechanism of cerebral infarction. The purpose of this study is to estimate the risk of cerebral infarction associated with microembolism in patients with ICS and thereby to determine the importance of TCD-detected microemboli in this condition. Seventy-one cases with more than 30% ICS and 10 cases without ICS were studied. TCD monitoring was carried out for an hour at the ipsilateral middle cerebral artery of each case using a 2-MHz pulse-wave transcranial Doppler device. High intensity transient signals were counted as microemboli. Microemboli were detected in 27 of 71 cases with ICS, but not in cases without ICS. Microemboli were detected more frequently in cases with 70% to 99% ICS (53.3%) compared with in cases with 30% to 69% ICS (12.5%). Cerebral infarctions were recognized in the ipsilateral hemisphere in 23 of 27 cases with microemboli (85.2%) by means of MRI. In contrast, cerebral infarctions were recognized only in 21 of 45 cases without microemboli (47.7%). These results suggest that a stenotic lesion of the extracranial internal carotid artery, especially high-grade stenosis, is a major source of cerebral embolism and that detection of microemboli by TCD is a useful tool capable of reliably assessing the risk of cerebral infarction due to ICS.

Aged↗
PubMed1997

Thyroxine-binding globulin and thyroid hormones after resection of hepatocellular carcinoma.

OBJECTIVES: Some human hepatocellular carcinomas (HCCs) produce thyroxine-binding globulin (TBG). High serum TBG levels in such patients may be associated with increased thyroxine (T4) levels. This study aimed to elucidate the serum TBG and thyroid hormone profile in Japanese patients with HCC, to compare the difference between TBG-producing and -nonproducing HCCs, and to investigate the changes in serum TBG level and the thyroid hormone profile after removal of the tumor. METHODS: The 40 subjects included 20 patients with HCC, 10 healthy controls, and 10 operative controls. Serum TBG, 3,5,3'-triiodothyronine (T3), T4, and free T4 were measured serially for 4 wk after resection of HCC in 16 patients and after control operations in 10 patients. Assay methods were a radioimmunoassay for TBG and enzyme immunoassays for T3, T4, and free T4. RESULTS: Values higher than the mean +/- 2 SD of controls were considered abnormally high. Of patients with HCC, 60% had abnormally high TBG values, 65% had abnormally high T3 values, 39% had abnormally high T4 values, and 6% had abnormally high free T4 values. The mean levels of TBG and T3 were significantly higher than those in healthy controls, but no difference was found for T4 and free T4 levels. There were no significant differences in various clinicopathological factors between patients with high TBG levels and those with normal TBG levels. After resection of HCC, serum TBG decreased significantly in patients with high TBG levels but not in those with normal TBG levels. CONCLUSIONS: This study shows that >50% of HCCs in Japanese patients produce TBG; removal of the tumor reduces serum TBG in such cases.

Adult↗
PubMed1997

[Analysis of factors related to microemboli in cases with internal carotid artery stenosis].

Transcranial Doppler ultrasound (TCD) has been used to detect microemboli in cases with extracranial internal carotid artery stenosis. However, the mechanism causing microemboli has remained unclear. The purpose of this study is to clarify clinical characteristics and circumstances associated with the genesis of TCD-detected microemboli. Ninety-one cases with more than 30% stenosis of the internal carotid arteries were studied. TCD monitoring was carried out for an hour at the ipsilateral middle cerebral artery of each case using a 2-MHz pulse-wave transcranial Doppler device, and high intensity transient signals were counted as microemboli. Digital subtraction angiography, magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) were also performed in all cases. Microemboli were detected in 30 of 91 cases. Microemboli were significantly well detected in cases with a history of ischemic event and/or cerebral infarction recognized by MRI. Detection of microemboli had no relation to sex, age or clinical risk factors (hypertension, hypercholesterolemia, diabetes mellitus and smoke habituation). In contrast, detection of microemboli was significantly related to decrease in cerebral blood flow recognized by SPECT, severity of stenosis and wall irregularity of lesion recognized by angiography. Microemboli can be found in a significantly high percentage of these clinical conditions, which may be risk factors for embolic stroke caused by extracranial internal carotid artery stenosis.

Aged↗
PubMed1997

[Effects of eicosapentaenoic acid in patients with bronchial asthma].

Eicosapentaenoic acid (EPA) is composed of 20 unsaturated fatty acids and is similar to arachidonic acid. Epadel, the drug made from EPA, is reported not only to reduce levels of serum lipids, but also to have antiinflammatory and antiallergic effects. EPA may exert these effects via control of the production of prostanoids and leukotrienes. We studied the effects of EPA in patients with bronchial asthma who had hyperlipidemia. The patents were given EPA at 1800 mg/day and they recorded signs and symptoms in an asthma diary during a 2-week observation period and the 8 weeks during which they took the drug. Peak flow, leukotriene B4 concentration in urine, Leukotriene E4 concentration in urine, IgE level, total cholesterol level, and triglyceride level were measured before and after the 8 weeks of medication. Administration of EPA was associated with improvements in symptom score, therapeutic score, asthma score, and peak flow. EPA may be useful in patients with asthma complicated by hyperlipidemia.

Adult↗
PubMed1997

[Detection of microemboli by transcranial Doppler sonography after carotid endarterectomy].

Transcranial Doppler sonography (TCD), a non-invasive monitoring technique, has potential for detecting microemboli caused by the extracranial internal carotid artery. Many previous reports have shown that TCD-detected microemboli may be a risk factor for stroke. The main purpose of this study is to verify whether microemboli cease after carotid endarterectomy (CEA). TCD monitoring was performed in 43 cases before and after CEA. TCD monitoring was carried out for an hour at the ipsilateral middle cerebral artery of each case using a 2-MHz pulse-wave transcranial Doppler device, and high intensity transient signals were counted as microemboli. Microemboli were detected preoperatively in 10 cases (23.3%). Microemboli were not detected in any case immediately after CEA, in either the subacute stage (from 14 to 21 days after CEA) or in the chronic stage (more than 3 months after CEA). In the acute stage (from 3 to 7 days after CEA), microemboli were detected in three cases (7.0%). The rate of TCD-detected microembolic was always significantly reduced after CEA. TCD monitoring can be helpful in assessing the effect of CEA for prevention of stroke by removing the suspected source of microemboli.

Aged↗
PubMed1997

Detection of embolic signals during and after percutaneous transluminal angioplasty of subclavian and vertebral arteries using transcranial Doppler ultrasonography.

OBJECTIVE: Percutaneous transluminal angioplasty (PTA) is accepted as a safe and effective procedure for the treatment of stenotic arterial lesions of various sites. However, distal embolism may cause serious complications in the PTA of cephalic arteries. By monitoring embolic signals using transcranial Doppler (TCD) ultrasonography, we speculated regarding the safety and/or risk of PTA for vertebral and subclavian artery stenosis. METHODS: Twelve consecutive patients undergoing PTA for subclavian and vertebral artery stenosis of atherosclerotic origin were studied. All patients were refractory to initial medical treatment and were considered for PTA. During the PTA procedure, all patients were heparinized. Before, during, and after PTA, TCD monitoring was performed to detect embolic signals for 30 minutes at each time. After PTA, anticoagulant and antiplatelet therapies were continued in all patients. RESULTS: Before, during, and after PTA, a steady flow signal could be obtained from each vertebral artery monitored using TCD ultrasonography. No embolic signals were detected in any patient before angioplasty. During angioplasty, one embolic signal was detected immediately after balloon deflation in 1 of 12 patients. Several embolic signals were detected after the procedure in 6 of 12 patients, but thereafter embolic signals became less frequent in number. Three days after angioplasty, embolic signals were not detected in any patient. There were no serious complications caused by the PTA procedure. CONCLUSION: TCD monitoring may be a useful modality for detection of microemboli during and after PTA in the posterior circulation. We suspected that subclinical microemboli are released from the dilated vessels for 3 days after vertebral and subclavian PTA and that anticoagulant or antiplatelet therapies may prevent embolic complications after the procedure.

Aged↗
PubMed1997

Mechanism of intracranial rebleeding in moyamoya disease.

Intracranial hemorrhage is the major catastrophic event in the natural course of Moyamoya disease, and outcome of the patients with rebleeding is very poor. However, the mechanism underlying intracranial rebleeding is not well elucidated. We retrospectively analyzed 15 patients who bled two times or more among 46 bled patients with Moyamoya disease. The results indicated that there were two different types in the manner of rebleeding. One group consisted of seven cases, which bled two times or more at the same site than the original bleeding site. In four of these seven cases, a ruptured aneurysm was identified at the distal part of collateral vessel or on the major vessel. In the other three cases, no source of bleeding was identified. In all of these cases, rebleeding occurred within 2 months after the initial insult except for one case. Another group consisted of eight cases, which bled repeatedly but at different sites from the initial bleeding site. In any of these cases, neither aneurysms nor other vascular abnormalities were identified. In all of these cases, rebleeding occurred more than 2 months after the initial bleeding. The present result indicated that intracranial bleeding might occur as a result of rupture of a tiny aneurysm at the periphery of collateral vessels. These aneurysms may be blown out after initial bleeding. When they persist after the event, they may rupture again in a fairly short interval. In other cases, bleeding occur at different sites from the initial site. They are considered to be a result of ruptured weak Moyamoya vessels which are forced to act as collateral pathways and are under unusually increased hemodynamic stress.

Adolescent↗
PubMed1997

[Clinical study on azithromycin in 10% fine granules and 100mg capsules in the field of pediatrics].

Azithromycin (AZM), a new oral macrolide antibiotic, in 10% fine granules or 100 mg capsules was given to pediatric patients to treat various infections. The following results were obtained in our studies of AZM for its antibacterial activities against clinical isolates, its pharmacokinetics, its efficacy, and its safety. 1. MICs of AZM, erythromycin (EM) and clarithromycin (CAM) were determined against a total of 57 strains all at 10(6) cfu/ml. Among Gram-positive cocci, MICs of AZM ranged from 0.78 to > 100 micrograms/ml against Staphylococcus aureus (20 strains), from 0.05 to 0.1 microgram/ml against Streptococcus pyogenes (11 strains), and from 0.0125 to 3.13 micrograms/ml against Streptococcus pneumoniae (10 strains). These MICs were similar to those of the other macrolides. Among Gram-negative bacilli, MICs of AZM were 0.05 micrograms/ml against Moraxella subgenus Branhamella catarrhalis (1 strain), from 0.78 to 3.13 micrograms/ml against Haemophilus influenzae (9 strains), 0.78 micrograms/ml against Haemophilus parainfluenzae (1 strain) and 6.25 micrograms/ml against salmonella sp. (1 strain). These values were similar to or lower than those of the other macrolides. Against Mycoplasma pneumoniae, MICs of AZM were < or = 0.0008 micrograms/ml in three strains. One strain of M. pneumoniae showed tolerance to AZM at MIC 25 micrograms/ml. The other agents exhibited higher MIC than AZM against this organism. 2. Plasma samples were collected from five patients receiving fine granules and four patients receiving capsules for drug level determination. The patients received AZM at 10.0 approximately 16.3 mg/kg body weight once daily for 3 days. Drug concentrations in plasma at two hours after Day 3 dosing were in a range between 0.02 and 0.19 micrograms/ml for fine granules and were in a range between 0.11 and 0.42 micrograms/ml for capsules. 3. Urine samples were collected from four patients receiving fine granules and four patients receiving capsules. Drug levels were determined to be 3 micrograms/ml at post-treatment 48 hours for fine granules and post-treatment 72 hours for capsules. Urinary excretion rates of AZM in three patients on capsules lied in a range between 4.69 and 10.17%. 4. Effectiveness of AZM in fine granules was evaluated in 128 patients having a total of 19 different infections. AZM was rated "excellent" in 51 patients, "good" in 63, "fair" in 8, "poor" in 6, resulting in an efficacy rate of 89.1%. Effectiveness of AZM in capsular form was evaluated in 23 patients with five different infections. AZM was found "excellent" in 13 patients and "good" in 10, resulting in an efficacy rate of 100%. 5. AZM in fine granules eradicated 45 strains of 54 in 8 different bacteria. AZM in capsules eradicated 9 strains of 10 strains in 6 different bacteria. 6. As for adverse reactions, one patient complained of eruption, one vomiting, one loose stool, five diarrhea, when administered with fine granular form of AZM. One patient on AZM capsules experienced urticaria and vomiting. 7. As for abnormal laboratory changes, three patients were found with decreased WBC, seven with increased eosinophil, two with increased GOT and GPT, one with increased GPT. They were all on fine granular form of AZM. As far as abnormalities found in patients administered with AZM in capsular form, two showed decreased WBC, one decreased WBC along with increased eosinophil, and three increased eosinophil.

Adolescent↗
PubMed1996

Changes of expressions of phosphotyrosine phosphatases in rat hepatocellular carcinoma induced by 3'-methyl-4-dimethylamino-azobenzene.

Using rats with hepatocellular carcinoma induced by 3'-methyl-4-dimethylamino-azobenzene (3'-MeDAB), we evaluated the expression of a protein tyrosine phosphatase (PTPase) in the tumor region, non-tumorous region and control rat liver. The expression of SHPTP2 increased 4.1 fold (p < 0.05) in mRNA, 2.1 fold (p < 0.01) in cytosol fraction, and 5.1 fold (p < 0.05) in membrane fraction, respectively, at a protein level in the tumor region compared with control liver. The expression of other phosphatases, LAR, LRP, and PTPase1B, did not change significantly. SHPTP2 phosphatase activity in the tumor region from rats also increased compared with control, suggesting that an increase of this activity may parallel the expression of SHPTP2. This increase of expression of SHPTP2 may contribute to the progression of hepatocellular carcinoma in this rat model.

Animals↗
PubMed1996

Analysis of numerical aberrations of specific chromosomes by fluorescent in situ hybridization as a diagnostic tool in breast cancer.

BACKGROUND: Biopsy by fine-needle, aspiration has become a routine technique for the diagnosis of a dominant breast mass. In this study, fluorescent in situ, hybridization (FISH) analysis of interphase nuclei allowed the authors to detect genetic aberrations that are difficult to identify by conventional cytology. METHODS: To investigate ways of minimizing misdiagnosis of the cytology of breast tumors, and detecting genetic aberrations preoperatively, the authors performed FISH with specimens obtained by fine-needle aspiration biopsies of 106 primary breast tumors (78 primary breast cancers, 2 phyllodes tumors, and 26 benign breast tumors). Numerical chromosome aberrations were investigated using 3-color FISH performed with (peri)centromere-specific probes for chromosomes 1, 11, and 17. RESULTS: Sufficient materials for FISH analysis were obtained with aspiration biopsy from 98 of the 106 breast tumors (93.4%). None of the benign tumors nor phyllodes tumors showed evidence of aneusomy for any of the 3 chromosomes. However, 71 of the 74 breast cancers (95.9%) for which sufficient material was available demonstrated aneusomy of at least 1 of the 3 chromosomes tested. The FISH analysis also suggested a possible correlation between aneusomy of chromosome 17 and metastasis to regional lymph nodes (chi-square test = 7.78; P < 0.05). CONCLUSIONS: FISH analysis of fine-needle aspiration biopsies can be a practical and useful method for the preoperative diagnosis of breast carcinoma.

Biopsy, Needle↗
PubMed1996

Arteriovenous malformation associated with moyamoya disease.

The first case of a child with an arteriovenous malformation (AVM) associated with moyamoya disease is reported. The patient presented ischemic symptoms and underwent indirect bypass surgery on both sides when she was 5 years old. Four years later she suffered from headache, and a small AVM of the left frontal lobe associated with the moyamoya vessels was detected. Single photon emission computed tomography (SPECT) was performed at age 11 and demonstrated low local cerebral blood flow (CBF) in the left frontal lobe and right temporal lobe, although the revascularization after the bypass surgery seemed to be effective, as judged on pancerebral angiography. We feel that brain ischemia due to the moyamoya disease may have played a causative role in the development of the AVM.

Blood Flow Velocity↗
PubMed1996

Histological changes in brain tissue and vasculature after intracarotid infusion of organic solvents in rats.

Organic solvents, such as ethanol or dimethyl sulphoxide (DMSO), have been used in liquid embolic agents. To investigate the effects of these solvents on the cerebral blood vessels and cerebral tissue, we subjected Wistar rats weighing 250-300 g to internal carotid artery infusion of 0.2 ml diluted ethanol (10%, 40% or 70%) or anhydrous DMSO (100%). Some rats were sacrificed 5 min after the infusion and the remainder at 10 days. Rats injected with ethanol at high concentration or DMSO showed extensive exudation of Evans blue at the site of injection 5 min after infusion, together with full-thickness necrosis of the wall of vessels and swelling of brain cells. In contrast, rats injected with 10% or 40% ethanol solution showed necrosis of only the intimal layer and partial necrosis of the medial layer and no brain swelling was observed. These findings suggest that ethanol at low concentration can be used as a relatively safe solvent for liquid embolic substances.

Animals↗