Relationship between Shear Stiffness Measured by MR Elastography and Perfusion Metrics Measured by Perfusion CT of Meningiomas.

BACKGROUND AND PURPOSE: When managing meningiomas, intraoperative tumor consistency and histologic subtype are indispensable factors influencing operative strategy. The purposes of this study were the following: 1) to investigate the correlation between stiffness assessed with MR elastography and perfusion metrics from perfusion CT, 2) to evaluate whether MR elastography and perfusion CT could predict intraoperative tumor consistency, and 3) to explore the predictive value of stiffness and perfusion metrics in distinguishing among histologic subtypes of meningioma. MATERIALS AND METHODS: Mean tumor stiffness and relative perfusion metrics (blood flow, blood volume, and MTT) were calculated (relative to normal brain tissue) for 14 patients with meningiomas who underwent MR elastography and perfusion CT before surgery (cohort 1). Intraoperative tumor consistency was graded by a neurosurgeon in 18 patients (cohort 2, comprising the 14 patients from cohort 1 plus 4 additional patients). The correlation between tumor stiffness and perfusion metrics was evaluated in cohort 1, as was the ability of perfusion metrics to predict intraoperative tumor consistency and discriminate histologic subtypes. Cohort 2 was analyzed for the ability of stiffness to determine intraoperative tumor consistency and histologic subtypes. RESULTS: The relative MTT was inversely correlated with stiffness (P = .006). Tumor stiffness was positively correlated with intraoperative tumor consistency (P = .01), while perfusion metrics were not. Relative MTT significantly discriminated transitional meningioma from meningothelial meningioma (P = .04), while stiffness did not significantly differentiate any histologic subtypes. CONCLUSIONS: In meningioma, tumor stiffness may be useful to predict intraoperative tumor consistency, while relative MTT may potentially correlate with tumor stiffness and differentiate transitional meningioma from meningothelial meningioma.

Influence of Oral Anaerobic Bacteria on Hematopoietic Stem Cell Transplantation Patients: Oral Mucositis and General Condition.

OBJECTIVE: Oral mucositis (OM) caused by infection facilitated by myelosuppression and immunosuppression can be controlled through oral care. We investigated changes in oral anaerobic bacterial flora during the onset of OM with hematopoietic stem cell transplantation (HSCT). METHODS: This study included 19 patients who underwent HSCT. All received professional oral care before initiating the preparative regimen. We assessed OM, oral health and obtained microbial samples from the oral cavity during 5 assessment points: before initiating the preparative regimen; the day before HSCT (day 1); and at 7, 14, and 30 days after HSCT. Microbial species were identified by using a mass spectrometer. RESULTS: The number of patients with serious OM increased initially after HSCT and decreased thereafter. Many Streptococcus species were identified before HSCT, but these gradually decreased and were replaced by coagulase-negative staphylococci. An increase in Candida species after HSCT and the identification of Enterococcus species were significantly associated with OM. Nutritional status recovery and prognosis were significantly worse in patients who developed OM. CONCLUSIONS: To the best of our knowledge, this study is the first which shows that anaerobic bacteria were identified in patients' oral flora before and after HSCT by using a mass spectrometer. These results indicate that Enterococcus species and Candida species may have been associated with OM. OM affected the patients' improvement in nutritional status and their prognosis. We concluded that it is important to provide more complete oral care instructions and interventions to prevent these bacterial infections.

High-Tc nodeless s±-wave superconductivity in (Y,La)FeAsO(1-y) with Tc=50 K:75As-NMR study.

We report on an (75)As-NMR study on the Fe-pnictide high-T(c) superconductor Y(0.95)La(0.05)FeAsO(1-y) (Y(0.95)La(0.05)1111) with T(c)=50 K that includes no magnetic rare-earth elements. The measurement of the nuclear-spin lattice-relaxation rate (75)(1/T(1)) has revealed that the nodeless bulk superconductivity takes place at T(c)=50 K while antiferromagnetic spin fluctuations develop moderately in the normal state. These features are consistently described by the multiple fully gapped s(±)-wave model based on the Fermi-surface nesting. Incorporating the theory based on band calculations, we propose that the reason that T(c)=50 K in Y(0.95)La(0.05)1111 is larger than T(c)=28 K in La1111 is that the Fermi-surface multiplicity is maximized, and hence the Fermi-surface nesting condition is better than that in La1111.

Evaluation of cervical myelopathy using apparent diffusion coefficient measured by diffusion-weighted imaging.

BACKGROUND AND PURPOSE: Intramedullary high signal intensity on T2-weighted imaging was frequently observed in patients with CSM, although this finding does not well correlate with severity or prognosis of CSM. Instead of this nonquantitative information, another measure for CSM is desired. The work was focused primarily on assessing the relationships between ADC values and clinical and radiologic severity for the diagnosis of CSM. MATERIALS AND METHODS: The relationship between ADC values measured in the spinal cord at 322 intervertebral levels of 66 patients and clinical factors were analyzed. RESULTS: ADC values in the spinal cord significantly increased with the degree of spinal cord compression and decreased with time after decompression surgery. Patients with higher ADC values had lower preoperative JOA scores and tended to show poorer clinical recovery. CONCLUSIONS: ADC values appear to indicate the severity of spinal cord compression and clinical recovery after decompression surgery, so spondylotic myelopathy may partly be predicted preoperatively by using ADC values.

Antiferromagnetic spin fluctuations and unconventional nodeless superconductivity in an iron-based new superconductor (Ca4Al2O(6-y))(Fe2As2): 75As nuclear quadrupole resonance study.

We report 75As nuclear quadrupole resonance studies on (Ca4Al2O(6-y))(Fe2As2) with T(c) = 27 K. Measurement of nuclear-spin-relaxation rate 1/T1 has revealed a significant development of two-dimensional antiferromagnetic spin fluctuations down to T(c) in association with the smallest As-Fe-As bond angle. Below T(c), the temperature dependence of 1/T1 without any trace of the coherence peak is well accounted for by a nodeless s(±)-wave multiple-gaps model. From the fact that its T(c) is comparable to T(c) = 28 K in the optimally doped LaFeAsO(1-y) in which antiferromagnetic spin fluctuations are not dominant, we remark that antiferromagnetic spin fluctuations are not a unique factor for enhancing T(c) among Fe-based superconductors, but a condition for optimizing superconductivity should be addressed from the lattice structure point of view.

Inverse correlation of HER2 with MHC class I expression on oesophageal squamous cell carcinoma.

BACKGROUND: As HER2 is expressed in 30% of oesophageal squamous cell carcinomas (ESCCs), T-cell-based immunotherapy and monoclonal antibodies targeted against HER2 are attractive, novel approaches for ESCCs. However, it was shown that there is an inverse correlation between HER2 and MHC class I expression on tumours. Thus, the correlation between HER2 and MHC class I expressions on ESCC was evaluated. METHODS: Expressions of MHC class I and HER2 in ESCC tissues (n=80) and cell lines were assessed by immunohistochemistry, fluorescence in situ hybridisation (FISH), and flow cytometry. We investigated whether HER2 downregulation with small interfering RNA (siRNA) in ESCC cell lines could upregulate the expression of MHC class I and the antigen presentation machinery components, and could increase their sensitivity for tumour antigen-specific CTLs. RESULTS: There was an inverse correlation between HER2 and MHC class I expressions in both tumour tissues and cell lines. Downregulation of HER2 with siRNA resulted in the upregulation of MHC class I expression, leading to increased CTL recognition by tumour antigen-specific CTLs. CONCLUSION: HER2-overexpressing ESCC tumour cells showed a reduced sensitivity for CTLs through the downregulation of MHC class I.

Diagnostic value of spinal MR imaging in spontaneous intracranial hypotension syndrome.

BACKGROUND AND PURPOSE: Spontaneous intracranial hypotension (SIH) presents with orthostatic headache, and the diagnosis is made on the basis of low CSF pressure and brain MR imaging findings characteristic of the disorder. However, a broad spectrum of symptoms and MR imaging findings of SIH is recognized, and some cases have no typical MR imaging abnormalities. SIH is believed to be caused by CSF leakage from the spinal dural sac, whereas the usefulness of MR imaging of the spine remains unclear. Our aim was to elucidate the diagnostic value of brain and spinal MR imaging MATERIALS AND METHODS: The sensitivities for the detection of SIH were retrospectively evaluated in 18 patients with SIH treated in our institutions between January 1998 and August 2007. RESULTS: Brain MR imaging detected abnormalities in 15 of the 18 patients (83%): diffuse pachymeningeal enhancement in 15 (83%), descent of the cerebellar tonsil in 13 (72%), brain stem sagging in 13 (72%), enlargement of the pituitary gland in 12 (67%), and subdural fluid collection in 13 (72%). Spinal MR imaging detected abnormalities in 17 of the 18 patients (94%): distention of the epidural veins in 14 (78%), epidural fluid collection on fat-saturated T2-weighted images in 16 (89%), and abnormal visualization of the nerve root sleeve in only 1 (6%). The sensitivity for SIH was 83% for brain MR imaging and 94% for spinal MR imaging. CONCLUSIONS: Spinal MR imaging is useful for the diagnosis of SIH, especially in the early stage.

Decreased diameter of the optic nerve sheath associated with CSF hypovolemia.

The subarachnoid space around the optic nerve can be detected by fat-saturated T2-weighted MR imaging of the orbit, and dilation of this space reflects increased intracranial pressure. We examined 3 patients with CSF hypovolemia with MR imaging of the orbit and measured the optic nerve sheath diameter before and after treatment. We showed that the subarachnoid space is decreased in patients with CSF hypovolemia and the usefulness of this finding.

Dural arteriovenous fistulas of the cavernous sinus with onset of intracerebral haemorrhage mimicking hypertensive putaminal hemorrhage.

We describe a patient with dural arteriovenous fistulas of the cavernous sinus (CS-dAVFs) who developed an intracerebral haemorrhage (ICH) mimicking hypertensive putaminal haemorrhage. Drainage into the superior ophthalmic vein (SOV) and inferior petrosal sinus (IPS) was not demonstrated on cerebral angiography, and only cortical venous reflux into the Sylvian vein was observed. In cases of venous drainage concentrated on the Sylvian vein, CS-dAVFs could indicate ICH with radiological appearance resembling putaminal haemorrhage.

Postoperative three-dimensional CT angiography after cerebral aneurysm clipping with titanium clips: detection with single detector CT. Comparison with intra-arterial digital subtraction angiography.

AIM: To assess the significance of three-dimensional computed tomography angiography (3D-CTA) in detecting remnant necks after cerebral aneurysm clipping. MATERIALS AND METHODS: A total of 59 patients (77 aneurysms) underwent surgery using titanium clips. Two blinded observers independently evaluated the presence of neck remnants on shaded-surface display (SSD) imaging, volume rendered (VR) imaging, and intra-arterial digital subtraction angiography (IADSA). RESULTS: Mean sensitivity and specificity for detecting neck remnants were 50.0 and 74.2% for SSD imaging, 61.5 and 82.8% for VR imaging, and 92.3 and 92.2% for IADSA, respectively. Receiver operating characteristic (ROC) analysis revealed excellent diagnostic performance for IADSA [mean area under ROC curve (Az)=0.97], and good diagnostic performance for 3D-CTA (Az=0.70 and 0.76 for SSD and VR, respectively). Specificity of VR was better than that SSD (p=0.082), however, there was no significant difference between them. CONCLUSION: Use of 3D-CTA techniques can facilitate postoperative evaluation.

Carotid-cavernous fistula associated with an intracranial lesion caused by cortical venous reflux.

SUMMARY: Digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) findings in 20 patients with carotid-cavernous fistula (CCF; 3 direct CCFs and 17 indirect CCFs) were retrospectively reviewed to evaluate venous drainage patterns that may cause intracerebral haemorrhage or venous congestion of the brain parenchyma. We evaluated the relationship between cortical venous reflux and abnormal signal intensity of the brain parenchyma on MRI. Cortical venous reflux was identified on DSA in 12 of 20 patients (60.0%) into the superficial middle cerebral vein (SMCV; n=4), the uncal vein (n=2), the petrosal vein (n=2), the lateral mesencephalic vein (LMCV; n=1), the anterior pontomesencephalic vein (APMV; n=1), both the APMV and the petrosal vein (n=1) and both the uncal vein and the SMCV (n=1). Features of venous congestion, such as tortuous and engorged veins, focal staining and delayed appearance of the veins, were demonstrated along the region of cortical venous reflux in the venous phase of internal carotid or vertebral arteriography in six of 20 patients (30.0%). These findings were not observed in the eight CCF patients who did not demonstrate cortical venous reflux. MRI revealed abnormal signal intensity of the brain parenchyma along the region with cortical venous reflux in four of 20 indirect CCF patients (20%). Of these four patients, one presented with putaminal haemorrhage, while the other three presented with hyperintensity of the pons, the middle cerebellar peduncle or both on T2- weighted images, reflecting venous congestion. The venous drainage routes were obliterated except for cortical venous reflux in these four patients and the patients without abnormal signal intensity on MRI had other patent venous outlets in addition to cortical venous reflux. CCF is commonly associated with cortical venous reflux. The obliteration or stenosis of venous drainage routes causes a converging venous outflow that develops into cortical venous reflux and results in venous congestion of the brain parenchyma or intracerebral haemorrhage. Hyperintensity of brain parenchyma along the region of cortical venous reflux on T2-weighted images reflects venous congestion and is the crucial finding that indicates concentration of venous drainage into cortical venous reflux.

Multiple spinal dural arteriovenous fistulas.

Multiple spinal dural arteriovenous fistulas (DAVFs) have been rarely reported and only two such cases are found in the literature. A 71-year-old man complained of muscle weakness and hypesthesia in both legs and angiographically diagnosed as thoracic DAVF. The fistula was surgically treated, however, the symptoms recurred 14 months after the first treatment. Angiography revealed a new fistula in the lumbar region and this was also treated surgically. In the previously reported cases of multiple spinal DAVFs, the second fistulas were also diagnosed after the initial treatment. Symptomatic patients after the initial treatment of DAVF should be re-examined angiographically.

Extradural neuromas at the petrous apex: report of two cases.

OBJECTIVE AND IMPORTANCE: Two rare cases of middle cranial fossa neuroma located in the epidural space at the petrous apex are reported. CLINICAL PRESENTATION: Two women, aged 58 and 49 years, were admitted to our hospital with diagnoses of cavernous sinus tumor. Analysis of preoperative computed tomography scans showed bone erosion of the petrous apex, and magnetic resonance imaging demonstrated the presence of an extradural mass located along the course of the petrous internal carotid artery in both patients. INTERVENTION: The tumor was completely removed in one patient and partially removed in the other by use of the epidural middle cranial fossa transpetrosal approach. In both patients, histological examination of tumor specimens revealed neuroma. CONCLUSION: Because surgical exploration revealed that these epidural tumors adhered tightly to the internal carotid artery, and because they had no relationship to the trigeminal nerve, facial nerve, or proximal greater superficial petrosal nerve, in our opinion, these tumors originated from the distal portion of the greater superficial petrosal nerve or the deep petrosal nerve. These neuromas were mainly found in a site under the cavernous sinus at the petrous apex, a location not previously reported.

Induction of mitochondrial heat shock protein 60 and 10 mRNAs following transient focal cerebral ischemia in the rat.

Heat shock proteins (HSPs) 60 and 10 are stress-inducible mitochondrial matrix proteins that form a chaperonin complex that is important for mitochondrial protein folding and function. The effect of cerebral ischemia on mitochondrial HSPs is unclear. The topographical and chronological patterns of HSP60 and HSP10 messenger ribonucleic acid (mRNA) expression and induction were investigated in the rat focal cerebral ischemia model. Focal cerebral ischemia was produced by transient middle cerebral artery occlusion for 30 or 90 min. Expression of mRNAs was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. RT-PCR analysis showed that both HSP60 and HSP10 mRNA levels increased significantly in the ischemic cortex from 4 to 24 h of reperfusion after 30 min of occlusion. In situ hybridization analysis demonstrated significant induction of both mRNAs in the whole ischemic cortex after 30 min of occlusion and in the dorsomedial border (penumbra) of the ischemic cortex and ipsilateral hippocampus after 90 min of occlusion. Expression patterns and the timing of the induction of both HSP60 and HSP10 mRNAs were identical throughout the experiments. Simultaneous induction of the mRNAs for the mitochondrial chaperonins, HSP60 and HSP10, in various regions in focal cerebral ischemia demonstrates that mitochondrial stress conditions persist concomitantly with cytosolic stress conditions in focal cerebral ischemia.

Simultaneous induction of mitochondrial heat shock protein mRNAs in rat forebrain ischemia.

Several investigations have postulated evidence of the involvement of apoptosis in delayed neuronal death following brief periods of global cerebral ischemia. Apoptosis may be closely linked to mitochondrial dysfunction. Heat shock protein (HSP) 60 and HSP10 are mitochondrial matrix proteins induced by stress and form the chaperonin complex that is implicated in protein folding and assembly within the mitochondria. This study investigated the induction of these mitochondrial stress protein genes in the hippocampal CA1 region and less vulnerable regions following transient forebrain ischemia. In situ hybridization analysis revealed that the induction pattern of HSP60 mRNA was identical to that of HSP10 mRNA throughout the entire ischemic course. No changes occurred in the expression of both mRNAs after 2 min ischemia. Strong induction of both mRNAs occurred in the CA1 region after 10 min ischemia and persisted until 1 d after reperfusion. In contrast, induction of both mRNAs in the less vulnerable regions was terminated by 1 d after reperfusion. These results demonstrate that mitochondrial stress conditions persist concomitantly with cytosolic stress conditions in regions vulnerable to transient forebrain ischemia.

High uptake of 123I-metaiodobenzylguanidine related to olfactory neuroblastoma revealed by single-photon emission CT.

We studied a case of olfactory neuroblastoma by noting 123I-metaiodobenzylguanidine (MIBG) uptake revealed by single-photon emission CT (SPECT). MR imaging revealed an enhancing tumor extending from the left nasal cavity to the bilateral anterior frontal cranial fossae. SPECT revealed high 123I-MIBG uptake in the enhancing tumor. SPECT-revealed 123I-MIBG uptake appears to be clinically useful for distinguishing olfactory neuroblastomas from other tumors, especially suprasellar meningiomas.

Induction of cyclooxygenase-2 messenger RNA after transient and permanent middle cerebral artery occlusion in rats: comparison with c-fos messenger RNA by using in situ hybridization.

OBJECT: Recently, two different cyclooxygenase (COX) genes, COX-1 and -2, were identified. In this study, topographic and chronological profiles of COX-2 messenger (m)RNA and c-fos mRNA expression were investigated using in situ hybridization after focal cerebral ischemia. METHODS: Rats undergoing permanent ischemia were decapitated at 30 and 90 minutes and at 2, 4, 8, and 24 hours after middle cerebral artery (MCA) occlusion, and rats undergoing transient ischemia were decapitated at 4, 8, and 24 hours after MCA occlusion that lasted for either 30 or 90 minutes. After brief transient MCA occlusion, c-fos mRNA was induced in the whole MCA territory, adjacent cortex (cingulate cortex), and distant brain regions such as the hippocampus and substantia nigra. In contrast, COX-2 mRNA was not induced in the ischemic core (lateral striatum) but only in the penumbral area (MCA cortex). Long transient and permanent MCA occlusion did not induce c-fos and COX-2 mRNAs in the ischemic core but strongly induced both mRNAs in the penumbral area (medial striatum and periphery of MCA cortex) and adjacent cortex (cingulate cortex). In brain regions distant from the ischemic territory, although c-fos mRNA was induced in the thalamus, substantia nigra, and hippocampus after extended transient and permanent occlusion, COX-2 mRNA was only induced in the bilateral hippocampi. The induction of COX-2 mRNA persisted in all locations even at 24 hours after MCA occlusion. CONCLUSIONS: The distribution of COX-2 mRNA induction was apparently different from that of c-fos mRNA after MCA occlusion. These results pertaining to COX-2 mRNA agree well with the previous observations of changes in prostaglandin metabolism induced by focal cerebral ischemia. However, whether this induction of the COX-2 gene contributes to the histopathological outcome of cerebral ischemia remains to be elucidated.

Activation of Arc gene, a dendritic immediate early gene, by middle cerebral artery occlusion in rat brain.

The effect of middle cerebral artery (MCA) occlusion on the activity-regulated cytoskeleton-associated protein (Arc) mRNA expression has been investigated using in situ hybridization. It was induced in the extensive regions of cerebral cortex, medial striatum, and distant areas such as the ipsilateral lateral septal nucleus, bilateral hippocampal formation and contralateral amygdala following MCA occlusion. In the hippocampal formation, it was induced in the granule cell layer and the stratum pyramidale at 1 h and in the molecular layer and in the stratum oriens and stratum radiatum bilaterally at 4 h. MK-801 pretreatment strongly attenuated the induction of Arc mRNA. The present results suggest that Arc may play an important role in the neuronal plasticity through NMDA activation following focal cerebral ischemia.

Induction of Rheb mRNA following middle cerebral artery occlusion in the rat.

Rheb is a recently identified member of the Ras super-family and is an immediate early gene that is rapidly and transiently induced in the hippocampal granule cells by NMDA-dependent synaptic activity in the long term potentiation paradigm. The close homologies with Ras and its rapid inducibility strongly suggest that Rheb shares many biochemical and signaling properties with Ras. The present study investigated the effect of middle cerebral artery (MCA) occlusion on the expression of Rheb mRNA in the rat brain. In situ hybridization autoradiography showed that Rheb mRNA was induced in the extensive regions of cerebral cortex and medial striatum surrounding the ischemic region and bilateral hippocampal formation following MCA occlusion. The induction of Rheb mRNA in the cingulate cortex persisted prominently at 24 h of MCA occlusion. Although the Rheb mRNA induction in the medial striatum and hippocampal formation decreased after 8h of occlusion, it still remained significant at 24h of occlusion. The data suggest the possibility that Ras signaling pathways can be implicated in the cerebral ischemia-elicited events through NMDA receptor activation.