The effects of repetitive compression on nerve conduction and blood flow in the rabbit sciatic nerve.

The objective of this study was to clarify the effect of repetitive compression on nerve physiology in an experimental rabbit model. We defined 80 mmHg as a compression force which caused temporary disturbance of nerve conduction and blood flow with a brief compression. The following compressions were applied for 30 minutes to rabbit sciatic nerves: continuous compression, low frequency release compression (1 second of release time every 30 seconds) and high frequency release compression (1 second of release time every 10 seconds). Compound nerve action potentials and nerve blood flow were evaluated from the start of compression until 30 minutes after release. Endoneurial microvascular permeability was evaluated with Evans Blue albumin. The repetitive compression groups showed delay in recovery of compound nerve action potentials and blood flow after release, with endoneurial oedema. These findings suggest that repetitive compression may increase the risk of breakdown of the blood nerve barrier.

Phase II trial of radiotherapy after hyperbaric oxygenation with chemotherapy for high-grade gliomas.

We conducted a phase II trial to evaluate the efficacy and toxicity of radiotherapy immediately after hyperbaric oxygenation (HBO) with chemotherapy in adults with high-grade gliomas. Patients with histologically confirmed high-grade gliomas were administered radiotherapy in daily 2 Gy fractions for 5 consecutive days per week up to a total dose of 60 Gy. Each fraction was administered immediately after HBO with the period of time from completion of decompression to irradiation being less than 15 min. Chemotherapy consisted of procarbazine, nimustine (ACNU) and vincristine and was administered during and after radiotherapy. A total of 41 patients (31 patients with glioblastoma and 10 patients with grade 3 gliomas) were enrolled. All 41 patients were able to complete a total radiotherapy dose of 60 Gy immediately after HBO with one course of concurrent chemotherapy. Of 30 assessable patients, 17 (57%) had an objective response including four CR and 13 PR. The median time to progression and the median survival time in glioblastoma patients were 12.3 months and 17.3 months, respectively. On univariate analysis, histologic grade (P=0.0001) and Karnofsky performance status (P=0.036) had a significant impact on survival, and on multivariate analysis, histologic grade alone was a significant prognostic factor for survival (P=0.001). Although grade 4 leukopenia and grade 4 thrombocytopenia occurred in 10 and 7% of all patients, respectively, these were transient with no patients developing neutropenic fever or intracranial haemorrhage. No serious nonhaematological or late toxicities were seen. These results indicated that radiotherapy delivered immediately after HBO with chemotherapy was safe with virtually no late toxicity in patients with high-grade gliomas. Further studies are required to strictly evaluate the effectiveness of radiotherapy after HBO for these tumours.

Thromboembolic Events Associated with Coil Protrusion into Parent Arteries after GDC Treatment.

SUMMARY: Aneurysm embolization using Guglielmi detachable coils(GDC) is gaining acceptance as a viable alternative to surgery in the treatment of cerebral aneurysms. During GDC treatment of cerebral aneurysms, thromboembolic events are the most frequent complications. As risk factors of thromboembolic events, large aneurysms, wide-necked aneurysms, use of the balloon-assisted technique and protruding coils into the parent arteries are previously reported. From March, 1997 till August, 2004, 270 consecutive patients were treated with GDC embolization at our institute. Fourteen (5.2%) patients with 14 aneurysms of these 270 patients presented with protruding coils into the parent vessels. Twelve aneurysms of these 14 aneurysms were small (diameter < 10 mm), and two were large (diameter 15 mm). Nine aneurysms had small necks (neck diameter < 4 mm), and five had wide necks(neck diameter > 4 mm). The fundus-toneck ratio ranged from 1.04 to 2.78, with an average of 1.53. In this series, ten patients (71%) were treated with balloon-remodelling technique because every patient had either a wide-necked aneurysm or complicated morphologic factors. These 14 aneurysms were divided into two groups according to the mode of coil protrusion, loop type and tail type protrusion. The first coil was protruded in five (36%) cases of 14 patients, four of these five cases presented with the loop type protrusion. The last coil was protruded in seven cases (50%), Five of these seven cases presented with the tail type protrusion. Diffusion-weighted imaging abnormalities were found for seven (50%) of 14 patients within 24 hours of the coiling procedures. Three (21%) of 14 patients showed small lesions (< 5 mm) in the subcortical white matter at the border zone or perforating regions. In four (29%) patients, large territorial infarctions (> 5 mm) were detected. Symptomatic complications occurred in four (29%) patients, and all of these four patients presented the loop type protrusion. One patient who had small infarctions experienced minimal deficits (slight motor weakness, quadrantic hemianopsia) after six days postprocedure and fully recovered by discharge after stronger systemic heparinization (24000U, for three days), aspirin (100 mg/day) and Ticlopidine (100 mg/day). Three patients who had large territorial infarctions experienced moderate deficits. Two patients were treated with stronger systemic heparinization and one with Argatroban (60 mg/day, for two days), and following aspirin (100 mg/day) and Ticlopidine (100 mg/day). Finally, two patiens were discharged with permanent minimal deficits (hypoesthesia only) and one with moderate hemiparesis. The infarctions related to the GDC procedures were more common sequelae in wide-necked aneurysms and coil protrusions, especially loop type protrusion. Although permanent neurological deficits were rare, the high rate of thromboembolic events associated with coil protrusion suggest that more aggressive medical treatment should be considered.

Stenting for atherosclerotic stenosis of the intracranial or skull base cerebral arteries. Effectiveness and problems.

SUMMARY: Since May 1992, we have performed percutaneous transluminal angioplasty (PTA) or stenting 70 times for 65 lesions in 62 patients with atherosclerotic stenosis of the intracranial or skull base cerebral arteries. Stenting was carried out nine times for nine lesions in nine cases. Stenting was performed on patients with an average age of 62. The patients were eight men and one woman. The stenotic lesions involved the internal carotid artery (petrous portion) in four cases, the internal carotid artery (cavernous portion) in two cases, the internal carotid artery (supraclinoid portion) in one case, the middle cerebral artery (M1) in one case, and the vertebral artery (V4) in one case. The degree of stenosis ranged from 70% to 99%, with a mean of 80%. A stent for coronary arteries was used in all cases. After PTA was carried out in four cases, their initial extension was inadequate, and dissection was performed in five cases after PTA. As for the results of the treatment, subarachnoid haemorrhage occurred in one case due to perforation by the guidewire, and a major deficit was accepted. During the operation, asymptomatic cerebral infarction by distal embolism occurred in one case. Although obstruction of the lesion occurred three months after treatment in one case, symptoms did not appear. Stents used for atherosclerotic stenosis of the intracranial or skull base cerebral arteries still do not have sufficient performance. Although the stenting had problems, such as a prolonged patent, in the present condition, it was effective in terms of recovery from complications due to PTA.

Education and propagation of intravascular surgery in okinawa.

SUMMARY: Okinawa is an island located on the southwest edge of the Japanese Islands in which about 1,300,000 people live, and is an area where selfconclusion type medical treatment is desired. In this area, intravascular surgery was only performed for several cases per year until 1998. From May 1999, intravascular surgery started being performed in earnest, and 140 or more cases of intravascular surgery per year were performed in 2002. In the meantime, various measures for the propagation and development of intravascular surgery that we undertook led to the increase in the number of cases. As a result, the choice of medical treatment has increased by propagating these medical treatments, and it seems that this has contributed to the welfare of the people of Okinawa.

Low-dose tissue plasminogen activator followed by planned rescue angioplasty reduces time to reperfusion for acute myocardial infarction treated at community hospitals.

The time from admission to reperfusion in patients with acute myocardial infarction (AMI) was compared according to the type of hospital and treatment strategy. A total of 164 patients with a first AMI within 12h of onset were enrolled at one tertiary emergency center (TEC) and 6 community hospitals (CHs). The subjects were randomly assigned to receive either primary percutaneous transluminal coronary angioplasty (PTCA) (TEC-primary PTCA and CHs-primary PTCA groups) or 800,000 units of intravenous monteplase, half the standard dose of a mutant tissue plasminogen activator (t-PA), followed by rescue PTCA if the Thrombolysis in Myocardial Infarction (TIMI) flow grade was 2 or less (TEC-monteplase and CHs-monteplase groups) on the first coronary angiogram. Sixty minutes after admission, TIMI flow grade 3 rates of the study groups were as follows, in descending order: TEC-monteplase group, CHs-monteplase group, TEC-primary PTCA group, and CHs-primary PTCA group (56%, 41%, 36%, and 8%, respectively; p<0.01). However, there was no significant difference in the final TIMI flow grade 3 rate among the 4 groups. In the CHs, the peak creatine kinase tended to be lower in the monteplase group than in the primary PTCA group. The results suggest that low-dose monteplase followed by rescue PTCA is an effective strategy for promoting early reperfusion in patients with AMI, especially those who are treated at CHs.

[Schwannoma of the cervical spinal cord with cervical angina: a case report].

A case of schwannoma of the cervical spinal cord presenting with cervical angina is reported. A 49-year-old man was admitted to our hospital with severe chest pain, cold sweats, and unconsciousness. Extensive cardiac examination showed no abnormal findings. Neurological deficits were muscular weakness and atrophy of the left arm, bilateral hypersthesia of the arms, and hyporeflexia of the left biceps. MRI revealed a tumor in the left side of the spinal canal between C4 and C5. The diagnosis was neurinoma of the left nerve root in C5. The tumor was completely removed surgically by laminectomy. Surgery confirmed that the tumor had originated from the left posterior root of C5 and that, histologically, it was schwannoma. The severe chest pain immediately disappeared after removal of the tumor with only dull post-operative chest pain remaining. We hypothesized that the severe chest pain was protopathic pain caused by compression of the anterior C5 root by the tumor and/or disturbance of the inhibitory pain mechanisms of the sympathetic nerve located in the posterior horn of the spinal cord. It must be kept in mind that cervical angina caused by spinal schwannoma is one of the differential diagnoses of chest pain.

Expression of enzymes and oncogene induced after radiotherapy and/or chemotherapy in patients with brain tumors.

The relationship between the degree of the expression of Cu/Zn SOD, GST-pi and bcl-2 in the initial and recurrent tumor tissue after radiotherapy and/or chemotherapy and the cellular heterogeneity obtained from DNA content by image cytometry was investigated. Subjects were 7 patients who had glial tumors which were surgically removed at onset and removed a second time at recurrence. Radiotherapy and chemotherapy were also administered after initial resection. Immunoreactivity for copper/zinc super oxide dismutase (Cu/Zn SOD), GST (glutathione-S-transferase)-pi, and bcl-2 were evaluated from routinely prepared tissue blocks. Tumors were classified into two groups by cytometric analysis of DNA ploidy in the G2M cell cycle phase. One tumor group consisted of single clonal cells in both the initial and recurrent tumors and the other group consisted of tumors with polyclonal cells in the initial and recurrent tumor. In this study, one patient (case 3) with single clonal cell glioblastoma at recurrence did not show high Cu/Zn SOD activity after radiotherapy and chemotherapy but showed a short survival time after recurrence. In three patients (cases 1, 2, 3) with single clonal-cell glioblastoma, the recurrent tumor cells showed high GST-pi immunoreactivity and survival time was short after recurrence. Tumor cells in two patients (cases 5, 7) with single clonal cell anaplastic glioma at recurrence, showed high GST-pi immunoreactivity and had a short survival time after recurrence. In three single clonal glioblastomas (cases 1, 2, 3), the recurrent tumor showed the increased bcl-2 immunoreactivity and showed a short survival time after recurrence. In two patients (case 5, 7) with single clonal cell anaplastic glioma at recurrence, tumor cells showed a high bcl-2 immunoreactivity and these patients showed a short survival time after recurrence. Although the number of subjects is very small, our study shows that the immunoreactivity of bcl-2 and GST-pi in malignant gliomas may be very important factors in radio- and chemosensitivity, and shows that GST-pi is induced by radiation and anti-cancer drugs.

[Efficacy of low-dose mutant tissue-type plasminogen activator followed by planned rescue percutaneous transluminal coronary angioplasty as reperfusion therapy for acute myocardial infarction].

OBJECTIVES: The efficacy of injection of a low-dose mutant tissue-type plasminogen activator (mt-PA), monteplase, followed by planned rescue percutaneous transluminal coronary angioplasty (PTCA) was compared with that of primary PTCA. METHODS: A total of 164 patients with acute myocardial infarction within 12 hr from onset were randomly assigned to a treatment with 80 x 10(4) U bolus of monteplase (Group M) or no administration (Group P) by the envelope method, followed by immediate angiography with angioplasty in patients with Thombolysis in Myocardial Infarction (TIMI) flow grade 0, 1 or 2. RESULTS: There were no differences in baseline characteristics between the two groups. Initial angiography showed a higher reperfusion rate (TIMI 2 + 3: 21% + 38% vs 13% + 9%, p < 0.001) and the median time to TIMI 3 was shorter (63 vs 78 min, p < 0.005) in Group M than in Group P, but the final TIMI 3 rate was similar (93% vs 96%). Peak creatine kinase was lower, and predischarge left ventricular ejection fraction measured in 70% of all patients was higher (59 +/- 9% vs 54 +/- 14%, p = 0.02) in Group M than in Group P. Recurrent ischemia with ST elevation occurred in three patients in Group M, but death, re-acute myocardial infarction or stroke did not occur in either group and the rate of bleeding complication was similar (4.9% vs 3.7%). PTCA was performed less frequently in Group M, but medical expenses were comparable in both groups. CONCLUSIONS: Low-dose mt-PA followed by rescue PTCA is effective for early recanalization and preservation of left ventricular function without increases in bleeding complications or medical expenses. These results suggest that low-dose mt-PA should be given to all patients with acute myocardial infarction who are scheduled to undergo primary PTCA.

Anaplastic meningioma with papillary, rhabdoid, and epithelial features: a case report.

A 74-year-old man manifested disturbed consciousness and right hemiparesis. Computed tomography revealed a left frontal parasagittal meningeal tumor with extensive peritumoral brain edema and skull invasion. Subtotal removal was performed. Five years later, he underwent two more operations of massive recurrences. Pathological studies revealed anaplastic meningioma with two different histological areas. One was an epithelial and meningothelial area, and the other was a papillary and rhabdoid area. In the papillary and rhabdoid area, small tumor cells with a high nucleus/cytoplasm ratio proliferated densely around the dilated central capillaries with a pseudopapillary pattern. Many rhabdoid cells (vimentin ++, cytokeratin AE1/AE3 +, epithelial membrane antigen [EMA] + +) tended to be distributed far from the central capillaries. There were many mitotic figures near the central vessels. Dense MIB1-positive nuclei were also observed near the central vessels. The trabecular pattern of the tumor cells in the epithelial area was quite different from the histological features of chordoid meningioma.

Brain metastasis of epithelioid sarcoma--case report.

A 20-year-old-female first presented with an epithelioid sarcoma of the right thumb, and the right thumb was amputated. Five years later, a metastasis was found in the right lower lung and a partial lobectomy was performed. Three years later, computed tomography showed a metastatic brain tumor in the left frontal lobe, which was removed surgically. Adjuvant radiotherapy and chemotherapy were given after all operations. Histological examination showed all resected tumors were epithelioid sarcoma. She has maintained a good activity of daily living level as an outpatient for 2 years, although subcutaneous metastases and bronchial lymph node metastases have been observed. Such intensive treatment of slowly growing tumors often prolongs survival time, even in patients with multiple metastases.