Presence of human herpesvirus 6 and herpes simplex virus detected by polymerase chain reaction in surgical tissue from temporal lobe epileptic patients

We investigated the presence of human herpesvirus 6 (HHV-6) and herpes simplex virus (HSV) in surgical tissue from temporal lobe epileptic patients. A total of 17 cases were studied, including eight males and nine females. The mean age was 24.9 +/- 11.1 years and the mean age of onset was 11.1 +/- 5.4 years. Five patients were diagnosed as encephalitis/meningitis and another three had a history of suspected encephalitis/meningitis, but no patient showed any obvious neurological symptom or mental handicap. Mesial and lateral temporal tissues were examined by polymerase chain reaction. Among six patients positive for HHV-6 (35%), the mesial temporal lobe was positive in four and the lateral temporal lobe was positive in three. Herpes simplex virus was positive in only one patient. Three of the six patients positive for HHV-6 did not show any apparent causes. Mild encephalitis/meningitis induced by HHV-6, a condition sometimes not recognized as encephalitis/meningitis, may be one of the most frequent causes of temporal lobe epilepsy.

Enhanced motor cortical excitability in the unaffected hemisphere after hemispherectomy

We evaluated motor cortical excitability of the unaffected hemisphere in three patients with intractable epilepsy who underwent hemispherectomy, using transcranial magnetic stimulation (TMS) and PET. TMS of the unaffected hemisphere evoked motor responses not only in the contralateral muscles but also in the ipsilateral ones in all the patients. A PET study in one patient showed activation of the unaffected motor cortex by movement of either arm. All of these responses were enhanced after the hemispherectomy, probably due to motor cortical disinhibition by transection of the corpus callosum. The PET study also showed postoperative activation of the premotor area of the unaffected hemisphere. These phenomena indicate posthemispherectomy neuroplastic reorganization leading to preservation of the motor function after the operation.

[Functional hemispherectomy for children aged 2 years or less for the treatment of intractable epilepsy caused by cortical dysgenesis]

Thirteen children aged 2 years or less who had intractable epilepsy caused by cortical dysgenesis underwent functional hemispherectomy. The cerebral malformations were hemimegalencephaly in 8 cases and focal cortical dysplasia in 5 cases. Among 11 children who were followed for at least 6 months after the operation (6 to 54 months with a median of 26 months), 5 were seizure-free, 4 achieved > 90% seizure reduction, and 2 achieved 50-90% reduction. Ventriculo-peritoneal shunt was placed in 3 children with hemimegalencephaly. After hemispherectomy, all the children showed improvement in psychomotor development. Development was accelerated in 3 seizure-free children. In children with cortical dysgenesis, functional hemispherectomy may result in remarkable seizure reduction and steady developmental progress.

Modification of peri-insular hemispherotomy and surgical results

OBJECTIVE

We modified the peri-insular hemispherotomy technique devised by Villemure and Mascott. Our modified technique and the surgical results obtained with this method are presented.

METHODS

The frontoparietal operculum is resected, and the resection cavity is connected with the lateral ventricle. Through this cavity, a transventricular corpus callosotomy and resection of the medial temporal structures are performed.

RESULTS

This technique was used for 34 patients, with satisfactory surgical results. Cerebrospinal fluid shunt placement was necessary for five patients, and incomplete callosal sectioning was postoperatively detected in three cases.

CONCLUSION

Our modification of the peri-insular hemispherotomy can be safely and effectively used to treat epilepsy caused by hemispheric lesions, even in cases without ventricular dilation.

Vacuum assisted cardiopulmonary bypass in minimally invasive cardiac surgery: its feasibility and effects on hemolysis

The present study describes a cardiopulmonary bypass (CPB) technique that incorporates vacuum assisted venous drainage and arterial return using a centrifugal pump in minimally invasive cardiac surgery (MICS). The technique was performed on 40 patients scheduled to undergo MICS. The proposed CPB technique enables a good operative field to be obtained even through a limited incision through the use of peripheral cannulation using small cannulae. Vacuum pressure was applied to the venous reservoir (-43 +/- 14 mm Hg) to maintain adequate CPB flow (>2.4 L x min-1 x M-2). The effects of CPB on hemolysis were subsequently compared between patients who underwent the proposed procedure (MICS group; n = 6) and a control group who underwent coronary arterial bypass grafting (CABG group; n = 6) with conventional CPB. Plasma free hemoglobin (FHb) increased and plasma haptoglobin (Hp) decreased during CPB in both groups, with no significant difference between the groups. By the next day, FHb had returned to pre-CPB levels whereas Hp remained lower in both groups. Again, these values did not differ significantly between groups. Thus, we conclude that the proposed CPB technique is useful in MICS with acceptable effects on hemolysis.

Multiple myeloma presenting high fever and high serum levels of lactic dehydrogenase, CRP, and interleukin-6

Two myeloma patients presented high fever with no signs or data indicating infection at diagnosis or relapse. Both patients had plasmablastic myeloma, and serum levels of lactic dehydrogenase (LDH) and CRP were extremely high. Plasmablastic morphology, high LDH, and CRP were recognized as poor prognostic factors, indicating a fulminant phase of multiple myeloma. Interleukin-6 (IL-6) was only high in measured cytokines. We proposed that IL-6 caused high fever and induced the fulminant phase in these 2 cases.

[Endovascular neurointervention for cerebral aneurysm]

Embolization would have an advantage in the treatment of cerebral aneurysms by eliminating the need for craniotomy. The recent protocol of endovascular treatment for cerebral aneurysm is classified into two main categories; is parent artery occlusion and intra-aneurysmal embolization. For aneurysms with a broad neck and large sac, it is recommended to consider proximal arterial occlusion if tolerance is confirmed by cerebral blood flow study at the time of balloon Matas' test. Parent artery occlusion is a classical technique, but still mandatory and effective clinically. In patients who have aneurysms with a has well-defined neck and who are not good candidates for craniotomy, intra-aneurysmal embolization would be recommended as an alternative means of treatment. Care should be taken to prevent problems and complications, including careful catheter and guidewire manipulation. Careful selection of cases and appropriate pre-, intra-, and post-procedure patient management is essential. Since the clinical application of Gugliemi's detachable coil (GDC) started, the potential of endovascular treatment for cerebral aneurysm has changed considerably. Preliminary results of embolization using GDC suggest that endovascular treatment would offer marked improvement in the management of patients harboring cerebral aneurysms.

[Endovascular neurointervention for intracranial dural arteriovenous fistula]

Dural arteriovenous fistula(DAVF) is an abnormal shunt within the dura matter or near the venous sinuses. Various congenital and idiopathic causes have been suggested, including such as venous sinus occlusion, trauma, surgery, and changes in hormone levels, but the exact etiology of the disease is unknown. The pattern of venous drainage seen on angiography was used as the basis for a classification of DAVF by Djindjian. Recent classification suggests that lesions that drain into the venous sinus or meningeal vein will behave only in a benign manner, whereas those that have subarachnoid venous drainage or alone or in addition will behave aggressively. Selection of treatment can be made from observation, carotid manual compression, transarterial or transvenous embolization, radiotherapy, or surgical intervention. The goal of treatment and consequently the techniques used, depends on the intensity of symptoms or the neurologic and, in particular, hemorrhagic risk posed by the type of venous drainage. The therapeutic decision depends also on the patient's general clinical status. Embolization can create a reduction of flow, which results in disappearance in symptoms and sometimes complete cure as seen at angiography. Complex DAVF must be treated with combined endovascular techniques plus neurosurgery or radiotherapy.

Usefulness of cerebral blood flow (CBF) measurements to predict the functional outcome for rehabilitation in patients with cerebrovascular disease (CVD)

PURPOSE

The objectives of this study were to (1) elucidate the relationship between the mean CBF in the whole brain (Av.mCBF) before rehabilitation of CVD patients and the BI score before and after rehabilitation, (2) determine whether the efficacy of rehabilitation can be predicted by measurement of the Av.mCBF, and (3) investigate what part of the brain was most important to improving the BI score.

MATERIALS AND METHODS

The Av.mCBFs in 160 patients with CVD were calculated by Patlak plots with 99mTc-HMPAO before rehabilitation, and we determined the BI score before and after rehabilitation. Based on the BI scores before and after rehabilitation, patients were divided into four groups: Group A, BI = 100; Group B, 80 < or = BI < or = 99; Group C, 60 < or = BI < or = 79; Group D, 0 < or = BI < or = 59. We evaluated the relationship between the Av.mCBF and BI score before and after rehabilitation.

RESULTS

The Av.mCBF before rehabilitation showed a tendency to be more correlated with the BI score after rehabilitation (r = 0.414, p < 0.0001) than before rehabilitation (r = 0.272, p = 0.0006). After rehabilitation, there was a tendency for the Av.mCBF value to increase in direct proportion to the BI score of the group: it was highest in Group A and lowest in Group D. The strongest correlation was found between the frontal lobe regional CBF before rehabilitation and the BI score after rehabilitation (r = 0.343, p < 0.0001).

CONCLUSIONS

Measurement of the Av.mCBF before rehabilitation of CVD patients will permit prediction of the efficacy of rehabilitation. Also the regional CBF of the frontal lobe is most important for improving the BI score.

Suppression of gamma activity in the human medial temporal lobe by sevoflurane anesthesia

We have reported the presence of continuous gamma (30-150 Hz) activity in the human medial temporal lobe (MTL). Since the MTL is involved in learning and memory, we speculated that MTL gamma activity is related to such higher brain functions. It is thus of interest to learn how this activity changes during different states of consciousness. In this study, we recorded electrocorticographic (ECoG) activity directly from the surface of the MTL after various doses of sevoflurane anesthesia. Five epileptic patients underwent electrode placement operations in which electrodes were attached to the surfaces of the MTL and the basal temporal lobe (BTL). Immediately following the operation ECoG was recorded from each patient under four concentrations of sevoflurane anesthesia (1.5, 2.0, 2.5 and 3.0%). Fast Fourier Transform (FFT) analysis was performed on the MTL ECoGs. Under the lowest sevoflurane concentration, MTL gamma activity was observed in all patients. However, gamma activity was progressively suppressed by increased concentrations of sevoflurane, in a dose-dependent manner. Sevoflurane has been known to reduce neuronal excitability in the rat hippocampus in vitro, probably by changing GABAergic inhibition. The reduction of MTL gamma in the present study may be the result of such a mechanism. Although memory function was not tested in this study, the amount of MTL gamma activity may be related to residual memory function during anesthesia.

[Thoracoscopic lobectomy (non rib-spreading method): versus a video assisted lobectomy and a conventional thoracotomy]

We analyzed 33 thoracoscopic lobectomy (non rib-spreading method: NR) cases and 33 video assisted lobectomy (VA) cases and 49 posterolateral thoracotomy (PL) cases, regarding post-operative changes in the serum enzyme levels, operative bleeding, required analgesic treatments, changes in the respiratory function and other factors. Regarding the post/pre-operative ratio of creatinin phosphokinase, bleeding and analgesic treatment NR was showed significantly lower levels than the other two methods. Regarding the post/pre-operative ratio of vital capacity of the lung NR was significantly less than PL for every six months after the operation. With NR the mean number of dissected mediastinal nodes was 14.2 +/- 7.4 which was not significantly different from VA and PL. We thus concluded that NR caused less thoracotomic damage and especially far less restrictive damage to the respiratory function than both PL and VA. NR may also result in a better quality of life than VA and PL. The node dissection required for NR is also not considered to be inferior to that for PL because the number of dissected nodes for NR was not significantly different from that for PL. Therefore, in cases presenting with clinical stage I primary lung cancer NR is thus considered to be indicated in order to obtain an improved post-operative quality of life.

MR images of ovarian carcinosarcoma

The MR imaging of an ovarian carcinosarcoma is described. The tumor was heterogeneous and showed very high-intensity on T2-weighted images and iso-intensity on T1-weighted images, with visible enhancement. Even though signal intensities were somewhat different from those of ovarian adenocarcinoma, the preoperative diagnosis of ovarian carcinosarcoma is still difficult.

Beta-1 (10-20 Hz) cortical oscillations observed in the human medial temporal lobe

During wakefulness, signals from subdural electrodes attached to the basal and medial temporal lobes of adult human epilepsy patients revealed a rhythmic oscillation in the beta-1 frequency range (10-20 Hz). This activity was more prominent in the medial than in the basal temporal cortex. We also observed simultaneous oscillations in alpha frequency activity in the medial and the basal temporal cortices. In an eyes-open condition, the alpha oscillation was attenuated, while the beta-1 oscillation in the medial temporal lobe was not. This is the first report that the beta-1 oscillation is present in the human medial temporal lobe. Since we recorded this activity from within the limbic system, beta-1 activity may be an analog of the hippocampal rhythmic slow activity observed in some animals.

Diffusion-weighted MR imaging in multiple sclerosis: comparison with contrast-enhanced study

OBJECTIVE

To assess the utility of cerebral diffusion-weighted MR imaging in the diagnosis of multiple sclerosis (MS) in comparison with contrast-enhanced T1-weighted imaging.

METHODS AND MATERIALS

We reviewed T2-weighted spin-echo (SE), fluid-attenuated inversion-recovery (FLAIR), contrast-enhanced T1-weighted SE and echo-planar diffusion-weighted images (DWIs) obtained in seven patients with definite MS on nine occasions.

RESULTS

In total, 94 plaques were demonstrated on T2-weighted SE and/or FLAIR images. A total of 13 of these plaques showed enhancement on contrast-enhanced T1-weighted images and hyperintensity on DWIs, and five non-enhancing plaques showed hyperintensity on DWIs.

CONCLUSION

Diffusion-weighted imaging, which provides information based on pathophysiology different from contrast-enhanced imaging, is a potential supplementary technique for characterizing MS plaques.

Interictal hyperperfusion observed in infants with cortical dysgenesis

We investigated increases of interictal regional cerebral blood flow (rCBF) in patients with intractable epilepsy caused by cortical dysgenesis. Using single photon emission computed tomography, we measured interictal rCBF of epileptic foci in 24 patients with cortical dysgenesis who achieved Engel Class I or II outcomes at least 1 year after surgical intervention. The patients included 14 males and ten females, ranging in age from 2 months to 34 years (mean 6 years and 5 months). In the interictal period, dysplastic areas showed hyperperfusion in four patients (17%), hypoperfusion in 15 (62%), and isoperfusion patterns in five (21%). Interictal hyperperfusion was found in four infants aged 3-4 months; three with focal cortical dysplasia and one with hemimegalencephaly. Our results suggest that interictal hyperperfusion may indicate the presence of an active epileptic focus in infants with cortical dysgenesis, but not in older children or adults with the same disorder. Given the risk of misinterpreting the normal side as hypoperfused, the phenomenon of interictal hyperperfusion in the epileptogenic area should be taken into account when diagnosing pediatric epilepsy caused by cortical dysgenesis.

Stereotactic radiosurgery for brain metastases using a linac system: evaluation of initial local response by imaging

PURPOSE

We analyzed the efficacy of initial local response of MBT by imaging obtained within two months after treatment, to determine if there are factors that may be important for the initial local response of the disease. If an earlier local tumor response can be expected from SRS, patients with a poor prognosis should be treated with this modality.

METHODS

Thirty-six patients with 59 lesions were treated by linac radiosurgery. The primary tumor, peripheral dose, tumor volume, and CT enhancement pattern of the tumor before treatment (homogeneous or ring-enhancing) were chosen as factors related to local tumor response and were used in the statistical analysis.

RESULTS

1) The initial local response of radiation-resistant tumors to conventional EBRT was worse than that of other tumors. The initial local responses of MBT from breast carcinoma, colon carcinoma, and pulmonary carcinoma were good. 2) Excluding radioresistant tumors, the cases irradiated at 25 Gy or more tended to show good local control. 3) No statistically significant differences were found between local response and factors such as the enhancement pattern and tumor volume in the analysis of MBT.

Rhabdomyosarcoma in a patient with mosaic Klinefelter syndrome and transformation of immature teratoma

A 27-year-old man was found to have a mediastinal tumour and the histological diagnosis was immature teratoma. Remission was achieved by chemotherapy and total resection. However, he developed anaemia and leukoerythroblastosis after 2 years of remission, and was referred to our hospital. Rhabdomyosarcoma cells were detected in the bone marrow and pleural effusion. Moreover, karyotype analysis of peripheral blood and bone marrow cells revealed mosaic-type Klinefelter syndrome. We diagnosed the case as transformation of teratoma into rhabdomyosarcoma in Klinefelter syndrome. Although intensive chemotherapy was performed, the patient died with meningeal infiltration.

Successful surgical treatment of a dural arteriovenous fistula at the craniocervical junction with reference to pre- and postoperative MRI

We report a 62-year-old woman who presented with a myelopathy at the lower thoracic level. Left vertebral angiography revealed a dural arteriovenous fistula (DAVF) at the craniocervical junction, draining into an anterior spinal vein. Below the T7 level, the spinal cord gave high signal on T2-weighted images and enhanced with Gd-DTPA. The patient was successfully treated by simple clipping of vein draining the DAVF. The abnormal signal intensity and contrast enhancement rapidly regressed, except in the conus medullaris. Regression of the parenchymal abnormality on serial MRI following treatment corresponded closely with postoperative improvement of neurological function.

A new MRI technique for demonstrating the surface of the brain together with the cortical veins

We assessed combining of surface-anatomy scanning (SAS) MRI and MR venography (MRV). We obtained SAS images with a half-Fourier single-shot fast spin-echo sequence, then MRV of the identical section with a two-dimensional phase-contrast technique. We then added the two sets of images. The combined images, which were obtained within 10 min, provided information about the surface anatomy and cortical veins. This simple technique is useful for demonstrating brain surface structures, especially in patients from whom one plans to excise a lesion.

Minimally invasive port-access coronary artery bypass grafting

The Port-Access endovascular cardiopulmonary bypass system (Heartport, Inc., Redwood City, CA, USA), a recent technological innovation in minimally invasive cardiac surgery, was conducted successfully in coronary artery bypass grafting on a 69-year-old woman. The left internal thoracic artery was harvested through a limited left anterior thoracotomy and anastomosed to the left anterior descending coronary artery on a protected and arrested heart. Intraoperative coronary angiography confirmed good graft patency. The patient was discharged from the hospital in good condition 7 days after the operation. This was the first successful minimally invasive Port-Access coronary artery bypass grafting in Japan.

Enhanced gamma (30-150 Hz) frequency in the human medial temporal lobe

We performed fast Fourier transformation power spectral analysis of the electrocorticogram in human medial temporal lobe during wakeful rest in six epileptic subjects. Compared with the electrocorticogram wave in the basal temporal lobe, which showed monotonic decline of spectral power across the frequency axis, the electrocorticogram wave in the parahippocampal gyrus was enhanced (or did not decline) in the gamma frequency range (30-150 Hz) in all subjects. Although it has been suggested that electrical oscillations of the hippocampus have functional roles in higher brain functions, namely learning and memory, the knowledge of hippocampal oscillations is largely limited to animal studies. The present results demonstrate that fast frequency oscillation is also present in the human medial temporal lobe, which has been reported in animal hippocampi. They also demonstrate the importance of recording very fast field potentials in human electrocorticograms. This fast oscillation is likely to play important functional roles related to learning and memory, possibly to induce long-term potentiation in the human medial temporal lobe.

Surgical treatment of a case of early infantile epileptic encephalopathy with suppression-bursts associated with focal cortical dysplasia

We report a surgically treated case of early infantile epileptic encephalopathy (EIEE) with suppression-bursts associated with focal cortical dysplasia. Tonic-clonic seizures followed by a series of spasms occurred about a hundred times a day at a few days of age. Interictal electroencephalogram (EEG) revealed a suppression-burst pattern that was predominant in the left hemisphere. Magnetic resonance imaging (MRI) suggested focal cortical dysplasia in the left prefrontal area. Combination therapies with antiepileptic treatments showed only partial efficacy. The patient underwent lesionectomy at age 4 months, after which he gradually showed psychomotor development and a decrease of spasms to 0-2 series daily. In cases of EIEE with focal cortical dysplasia, surgical treatment may have beneficial effects on both psychomotor development and seizure control.

Clinical outcome in three patients with myelodysplastic syndrome showing polyclonal hematopoiesis

The clinical outcome of 3 myelodysplastic syndrome (MDS) patients with polyclonal hematopoiesis is reported. All patients were heterozygous for the phosphoglycerate kinase (PGK) gene. The presence of polyclonal hematopoiesis was determined by the X-chromosome-linked restriction fragment length polymorphism-methylation method using the PGK gene as a marker. The patients were initially diagnosed as having refractory anemia (RA), RA with ring sideroblasts (RARS), and RA with an excess of blasts (RAEB), respectively. Their pancytopenia persisted during the follow-up period of 11.4 years for the RA patient, 19.5 years for the RARS patient and 0.8 years for the RAEB patient. Although the RARS patient continues to be in good health, leukemic transformation occurred in the other 2 patients. A karyotype change from 46,XX to 45,XX,t(3;21),-7 was observed at the time of disease progression in the RA patient. The coexistence of a monoclonal MDS clone and normal bone marrow cells is thought to be the most probable reason for the polyclonal hematopoiesis of these patients.