Hitoshi Yamahata

Thromboprophylaxis in Hip Fracture Surgery: A Pilot Study Comparing Danaparoid, Enoxaparin and Dalteparin

A pilot study was performed to compare the thromboprophylactic effect of danaparoid, enoxaparin and dalteparin in patients with hip fracture. The study was a prospective, randomised assessor-blind, four-centre trial. Prophylaxis was given for 9–11 days, whereafter bilateral phlebography was performed. A total of 197 patients were randomised. There were no statistically significant differences in the frequency of deep vein thrombosis, in blood loss or bleeding complications between the three prophylaxis groups. In conclusion, this moderately sized study revealed no statistically significant difference in efficacy or safety between danaparoid, enoxaparin and dalteparin in patients undergoing hip fracture surgery.

Cranial surgery without head shaving

OBJECTIVE Based on a series of 632 patients who underwent craniotomy without head shaving, we report the efficacy and safety of our simplified procedure and document the usefulness of the electrosurgical scalpel. METHODS After brushing a chlorhexidine-alcohol solution onto the craniotomy site, the hair was parted from the incision line and fixed with adhesive paper drapes. In recent cases, electrosurgical scalpels were used for scalp- and subcutaneous dissection. At the end of surgery, the wound was closed in the usual manner, taking care that no hair was in the wound and the hair and wound were rinsed with clean water in the operating room. We did not apply disinfectant for postoperative wound care, rather, the hair was shampooed on the 2nd, 4th, and 6th postoperative day. RESULTS Among 632 patients who underwent cranial surgery without head shaving, only 7 (1.1%) developed postoperative wound infections. None of the 34 patients who underwent craniotomy using the electrosurgical scalpel developed wound infections. CONCLUSIONS Our simplified cranial surgery without head shaving does not increase the risk of wound infection. Because the use of the electrosurgical scalpel for skin and soft tissue dissection minimizes bleeding, the probability of wound infection appears to be reduced.

Clinical presentation and treatment of aneurysms associated with basilar artery fenestration

Aneurysms associated with a fenestrated basilar artery are rare, and treatment strategies have yet to be established. A direct surgical approach to the basilar artery is challenging because the surrounding anatomy is complex. We retrospectively compared the clinical features and treatment outcomes of eight patients (seven female, one male) with aneurysms associated with a fenestrated basilar artery after clipping or coil embolisation and reviewed the literature. Of the eight aneurysms, four were ruptured; seven aneurysms were located at the proximal part of the basilar artery and one aneurysm was located at the middle of the basilar artery. Six aneurysms were surgically treated. Four aneurysms were embolised with Guglielmi detachable coils, two aneurysms were clipped via the transcondylar or temporopolar approach, and two aneurysms were not treated. All six surgically treated patients had good outcomes. We found that both coil embolisation and direct clipping to treat aneurysms associated with a fenestrated basilar artery have advantages and disadvantages. To obtain favourable outcomes, the selected treatment modality must consider the patients age and clinical condition, the aneurysm size and shape, the direction of the dome, the relationship with perforators, and the neurosurgeons expertise.

Efficacy and safety of the pterional keyhole approach for the treatment of anterior circulation aneurysms.

Keyhole surgery is partly replacing the standard pterional approach in patients undergoing surgery to treat aneurysms of the anterior circulation. We describe the pterional keyhole approach for the clipping of anterior circulation aneurysms and discuss the efficacy and safety of our keyhole craniotomy procedure. We treated 103 patients with 111 intracranial aneurysms by surgical clipping via the pterional keyhole approach and retrospectively compared the characteristics and clinical outcomes of the keyhole procedure and the standard pterional approach. We also compared the surgical results of the keyhole approach when the operator was an experienced neurosurgeon or a less experienced neurosurgeon guided by an experienced colleague. All keyhole operations were carried out successfully without enlargement of the craniotomy or a change to a different approach. The outcomes of the keyhole and the standard pterional approach in patients with subarachnoid hemorrhage were not significantly different. Favorable outcomes were obtained in patients with unruptured aneurysms treated by either experienced or less experienced surgeons. The pterional keyhole approach offers the same surgical possibilities as conventional pterional approaches for the treatment of anterior circulation aneurysms. It is safe and simple and yields favorable outcomes even if the operators are less experienced neurosurgeons. Careful patient selection and sufficient opening of the sylvian fissure are the key points for good outcomes and the prevention of intraoperative complications.

Subfrontal schwannoma mimicking neuroblastoma: case report.

Computed tomography (CT), performed in a healthy 28-year-old man after minor head injury, detected a frontal base tumor. Neurological examination revealed left hyposmia. On magnetic resonance imaging scans, there was a heterogeneously enhanced tumor located in the left paramedian frontal base with extension into the left ethmoid sinus. Angiography showed a hypervascular mass in the left anterior cranial fossa; it was mainly fed by the left ethmoidal artery. Positron emission tomography scanning showed moderate accumulation of 11-methylmethionine and low accumulation of 18-fluorodeoxyglucose (FDG) at the tumor site. Bone image CT disclosed compressive, nondestructive deformation of the left frontal base. The preoperative diagnosis was olfactory neuroblastoma or meningioma. The tumor was totally resected via bifrontal craniotomy. The tumor was histologically diagnosed as typical schwannoma; it was positive for S-100 protein. We report a rare subfrontal schwannoma with extension into the nasal cavity that mimicked neuroblastoma. Low FDG accumulation and compressive deformation of the anterior skull base may help in the differential diagnosis of these tumors.

Recombinant thrombomodulin inhibits thrombin-induced vascular endothelial growth factor production in neuronal cells.

Thrombin is a serine protease which is generated from its precursor prothrombin by the activation of the blood coagulation cascade. Thrombin converts fibrinogen to fibrin, activates platelets and several coagulation factors, and plays a central role in thrombosis and hemostasis by regulating platelet aggregation and blood coagulation. Here, we show that thrombn enhanced vascular endothelial growth factor (VEGF) production in a dose- and time-dependent manner in the supernatant of cultured PC-12 cells, as determined by enzyme-linked immunosorbent assay (ELISA). Thrombin receptor agonist peptide (SFLLRNPNDKYEPF, TRAP) exerted an effect similar to thrombin on VEGF production. Thrombin-induced VEGF production was significantly attenuated by recombinant human thrombomodulin (rTM) and its minimal functional domain E456. Furthermore, the antioxidant N-acetyl-L-cysteine (NAC) markedly inhibited thrombin-induced VEGF production. Thus, rTM and NAC apparently inhibited the effect of thrombin on VEGF production in neuronal cells.

Immunoreactivity of Wnt5a, Fzd2, Fzd6, and Ryk in glioblastoma: evaluative methodology for DAB chromogenic immunostaining

The aim of this study was to determine the influence of Wnt5a and its receptors on the survival of glioblastoma patients and to determine reliable evaluation methods for immunohistochemistry. Diagnostic specimens from 41 histopathologically confirmed primary glioblastoma patients whose Gd-enhanced tumors had been totally removed were immunohistochemically stained for Wnt5a, Fzd2, Fzd6, and Ryk. The immunoreactivity was evaluated using the following methods: (A) grayscale optical density after color deconvolution, (B) percentage of stained cells, (C) density of stained cells, (D) staining amount (multiplication product of B and C), and (E) staining rank. The data sets of A to E were statistically evaluated by correlation matrix analysis and regression analysis. The influence of the expression of the markers on survival was analyzed using a proportional hazard model. The results of color deconvolution (A) were well correlated with the results of the staining rank (E). In the semiquantitative results (B, C, and D), the staining amount (D) tended to show a better correlation with results of color deconvolution (A). Among all data sets, color deconvolution (A) demonstrated the most preferable fit in a proportional hazard model, and the expression of Fzd2 and Fzd6 was associated with poor prognosis in glioblastoma patients.

Improvement in treatment results of glioblastoma over the last three decades and beneficial factors

Abstract Background. The purpose of this study is to elucidate the trend of glioblastoma outcome and scrutinize the factors contributing to better outcome over three decades. Methods. Survival time and the influencing factors were retrospectively analyzed in 223 newly diagnosed primary glioblastoma patients during 1980–2010. Appraised factors included age, sex, tumor site, year of surgery, extent of resections, use of surgery supporting system, Karnofsky Performance Status (KPS), chemotherapy, conventional external beam radiotherapy (EBRT), and CyberKnife stereotactic radiotherapy (CK-SRT) use. Results. The median survival time (MST) in all patients was 13.6 months. The MSTs for 4 periods were 9.8 (1980–1990), 13.7 (1991–2000), 12.9 (2001–2005), and 15.8 months (2006–2010), respectively (p = 0.0047). Total resection, subtotal resection, partial resection, and biopsy had MSTs of 31.8, 13.9, 11.4, and 7.0 months, respectively (p < 0.0001). Regarding chemotherapy, MSTs of the temozolomide base group and nimustine hydrochloride (ACNU) base group were 16.9 and 14.6 months, respectively, whereas the MST of patients without chemotherapy was only 9.8 months (p < 0.0001). The MSTs for 40-Gy EBRT plus CK-SRT and 60-Gy EBRT were 19.1 and 10.7 months, respectively (p < 0.0001). But in sub-selected patients, treated during 2001–2010, whose resection rate was total resection or subtotal resection, EBRT was completed and postoperative KPS was greater than or equal to 70, the MST with and without CK-SRT was 26.6 and 18.3 months, respectively (p = 0.1529). According to the Cox proportional hazards model, degree of resection, KPS, ACNU use, temozolomide use, bevacizumab use, EBRT dose, and CK-SRT use were good prognostic factors. Use of neuronavigation and use of intraoperative magnetic resonance imaging were related to higher resection rate, but not determined as prognostic factors. Conclusions. We observed a gradual improvement in glioblastoma outcome, presumably because of improvements in therapeutic modalities for surgery, anticancer agents, and radiation, but the efficacy of CK-SRT remains unclear.

Expression of the JAK/STAT3/SOCS3 signaling pathway in herniated lumbar discs

The inflammatory cytokine interleukin-6 (IL-6) plays an important role in causing symptoms of lumbar disk herniation. The present study clarifies the expression of the signaling pathway of IL-6 in herniated discs. Homogenates prepared from lumbar herniated discs from 10 patients were assessed. The expression of janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), phosphorylated (p)-STAT3 at Tyr(705), suppressor of cytokine signaling 3 (SOCS3) and actin was examined by Western blot analysis. The expression of JAK1, STAT3, and p-STAT3 at Tyr(705) was also examined by immunostaining. JAK1, STAT3, p-STAT3 at Tyr(705) and SOCS3 were detected in almost all cases. Immunoreactivity against JAK1 and STAT3 was observed mainly in chondrocytes, whereas immunoreactivity against p-STAT3 at Tyr(705) was observed in the nuclei of chondrocytes. The JAK/STAT signaling pathway might be activated by IL-6 and transmit messages from the cell surface to the nucleus, and the pathway is negatively regulated by SOCS3. These JAK1, STAT3 and SOCS3 molecules might tightly regulate and play a role in the degeneration of chondrocytes within herniated discs.

Three Cases of Spontaneous Superficial Temporal Artery Aneurysm with Literature Review

Spontaneous, nontraumatic, superficial temporal artery (STA) aneurysms have been rarely reported. We herewith report three cases of spontaneous and true STA aneurysms. All patients, a 65-year-old male, a 76-year-old female, and a 47-year-old female, had no history of head trauma that requires medical attention. Painless, pulsatile, and slowly growing calvarial lump was the symptom leading to image studies. All the lumps were preoperatively diagnosed as STA aneurysms by magnetic resonance angiography and/or three-dimensional computed tomographic angiography. One case was accompanied by anterior communicating aneurysm. And another case was associated with two more scalp aneurysms arising from occipital artery and contralateral STA. Pathologic studies showed that all three were true aneurysms, with intact media and adventitia but without organized hematoma. Literature review showed that 8% of all STA aneurysms comprised spontaneous STA aneurysms. We found 32 cases (19 males and 13 females) of well-described spontaneous STA aneurysms including ours. Twenty-eight cases (87.5%) were true aneurysms. Seven cases (21.9%) had coexisting vascular lesions. Five (15.6%) of these seven cases were diagnosed with cerebral or abdominal aneurysm. Multiple scalp aneurysms are quite rare; only two cases including ours have been reported. It seems important to know that spontaneous STA aneurysms may coexist with other vascular lesions including intracranial aneurysm.