Cerebral Glucose Metabolism in Patients with Chronic Disorders of Consciousness.

OBJECTIVE: To measure regional cerebral metabolic rate of glucose (CMRGlu) in patients with chronic disorders of consciousness (DOCs) using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). METHODS: This retrospective cohort study examined 50 patients (mean age: 40.9 ± 20.1 years) with traumatic brain injury (TBI)-induced chronic DOCs [minimally conscious state (MCS)+, n = 20; MCS-, n = 15 and vegetative state (VS), n = 15]. We measured FDG-PET-based CMRGlu values in 12 regions of both brain hemispheres and compared those among MCS+, MCS - and VS patients. RESULTS: In both hemispheres, the regional CMRGlu reduced with consciousness deterioration in 11 of 12 regions (91.7%). In seven right hemisphere regions, CMRGlu values were markedly higher in MCS+ patients than in MCS- patients. Furthermore, CMRGlu was suggestively higher in the left occipital region in MCS- patients than in VS patients. CONCLUSION: Functional preservation in the left occipital region in patients with chronic DOCs might reflect an awareness of external environments, whereas extensive functional preservation in the right cerebral hemisphere might reflect communication motivation.

Spastic muscle stiffness evaluated using ultrasound elastography and evoked electromyogram in patients following severe traumatic brain injury: an observational study.

OBJECTIVE: To determine the relationship between muscle stiffness assessed using ultrasound shear wave elastography, spinal motor neuron excitability assessed using the F wave, and clinical findings of spasticity in patients with spastic muscle overactivity following severe traumatic brain injury. METHODS: This study enrolled 17 inpatients with severe traumatic brain injury and 20 healthy volunteers. Biceps brachii muscle stiffness was then evaluated using ultrasound shear wave speed. Spinal motor neuron excitability was evaluated using the F/M ratio recorded from abductor pollicis brevis muscle. Clinical parameters, such as the modified Ashworth scale and modified Tardieu scale, were assessed in the patient with traumatic brain injury. RESULTS: The patients with traumatic brain injury group had a significantly higher shear wave speed and F/M ratio compared with the healthy group. A higher shear wave speed was correlated with higher clinical spastic severity in patients with traumatic brain injury. The F/M ratio was not significantly correlated with clinical spastic severity. CONCLUSION: Ultrasound shear wave elastography might be helpful for assessing muscle stiffness in patients with spastic muscle overactivity following severe traumatic brain injury. Further studies comprising larger cohorts are warranted.

[A Case Report of Surgical Resection of a Supraseller Granuloma in a Patient with Erdheim-Chester Disease].

Erdheim-Chester disease(E-CD)is a rare pathology characterized by systematic granulomatosis that occasionally involves the central nervous system. We report about a 68-year-old woman with E-CD who presented with right-side visual disturbance. Magnetic resonance imaging showed a suprasellar tumor that elevated the right optic nerve and involved the right internal carotid and right anterior choroidal arteries. The tumor was partially resected via a trans-Sylvian approach and was histologically diagnosed as a granuloma. Considering the abnormal findings of postoperative X-ray and 99 mTc bone scintigraphy of the long bones, the pathology was diagnosed as E-CD. After surgery, her right-side visual disturbances disappeared. However, 1 year later, she died of systemic infection and heart failure. Histological autopsy findings indicated numerous yellowish nodules in the heart, lung, and kidney with pericardial and pleural effusions and whole-body granulomatosis, including the brain. E-CD is a rare but critical disease. This pathological entity should be considered when encountering cases of intracranial granuloma to ensure its early diagnosis and appropriate treatment. Surgical resection of intracranial granulomas in patients with E-CD may promptly improve neurological dysfunction.

Multidisciplinary attentive treatment for patients with chronic disorders of consciousness following severe traumatic brain injury in the NASVA of Japan.

Primary Objective: The aim of this study was to demonstrate the clinical outcomes of long-term multidisciplinary attentive treatment (MAT) in patients with chronic disorders of consciousness (DOC) due to severe traumatic brain injury (TBI) following automotive accidents.Research Design: Five hundred and ten patients (mean age: 40.4 years) were enrolled in this retrospective study.Methods and Procedures: Patients were provided MAT for one to several years in the eight medical facilities of the National Agency for Automotive Safety and Victims' Aid (NASVA) in Japan. Clinical status for consciousness, communication, and activities of daily living were evaluated using the NASVA grading system.Outcomes and results: Following MAT, NASVA scores at discharge were significantly improved compared to those at admission in every patient subgroup including sex, age, NASVA score, and association with/without hypoxic encephalopathy at admission. Younger age, shorter interval between injury and admission, and better neurocognitive function at admission were found to be significant and independent factors for a good prognosis.Conclusions: MAT can partially improve the cognitive and physical abilities of patients with chronic DOC. From the perspective of not only restoring a patient's daily life, but also reducing the caregiver's burden, this type of treatment program warrants more public attention.

[A Case of Glioblastoma that Appeared One Year after the Removal of Subcortical Hematoma].

Subcortical bleeding from brain tumors is not rare. In the majority of cases, tumors are revealed within a few months after bleeding. We herein report a relatively rare case of glioblastoma(GBM)that appeared one year after the removal of a subcortical hematoma. A 70-year-old woman suddenly began experiencing headache, vomiting, and aphasia. CT revealed a subcortical hematoma in the left superior temporal lobe and subarachnoid bleeding. Neither aneurysms nor abnormal signs suggesting a malignant tumor were noted during cerebral angiography. The hematoma was completely removed via craniotomy, and she was discharged with no neurological deficit.(MRI performed seven months after the surgery showed neither space-occupying lesions in the left temporal lobe nor brain edema. Twelve months after the initial surgery, she had aphasia again. CT and MRI revealed an enhanced mass lesion in the left temporal lobe. Positron emission tomography findings strongly indicated the presence of a malignant tumor. Histology of the tumor after removal showed GBM HDH-1 wild-type with an MIB-1 labelling index of approximately 50%. After the surgery, she underwent extensive local radiation therapy(50 Gy)with chemotherapy(temozolomide). The pathological mechanism underlying the appearance of GBM at the site where subcortical bleeding was previously observed is unclear. GBM may have caused bleeding or may have originated from the brain tissue that was damaged during the first surgery. Follow-up using neuroimaging for one year may be needed when subcortical bleeding is observed.

Characteristics of time-activity curves obtained from dynamic 11C-methionine PET in common primary brain tumors.

PURPOSE: The aim of this study was to assess whether dynamic PET with 11C-methionine (MET) (MET-PET) is useful in the diagnosis of brain tumors. METHODS: One hundred sixty patients with brain tumors (139 gliomas, 9 meningiomas, 4 hemangioblastomas and 8 primary central nervous system lymphomas [PCNSL]) underwent dynamic MET-PET with a 3-dimensional acquisition mode, and the maximum tumor MET-standardized uptake value (MET-SUV) was measured consecutively to construct a time-activity curve (TAC). Furthermore, receiver operating characteristic (ROC) curves were generated from the time-to-peak (TTP) and the slope of the curve in the late phase (SLOPE). RESULTS: The TAC patterns of MET-SUVs (MET-TACs) could be divided into four characteristic types when MET dynamics were analyzed by dividing the MET-TAC into three phases. MET-SUVs were significantly higher in early and late phases in glioblastoma compared to anaplastic astrocytoma, diffuse astrocytoma and the normal frontal cortex (P < 0.05). The SLOPE in the late phase was significantly lower in tumors that included an oligodendroglial component compared to astrocytic tumors (P < 0.001). When we set the cutoff of the SLOPE in the late phase to - 0.04 h-1 for the differentiation of tumors that included an oligodendroglial component from astrocytic tumors, the diagnostic accuracy was 74.2% sensitivity and 64.9% specificity. The area under the ROC curve was 0.731. CONCLUSIONS: The results of this study show that quantification of the MET-TAC for each brain tumor identified by a dynamic MET-PET study could be helpful in the non-invasive discrimination of brain tumor subtypes, in particular gliomas.

11C-methionine positron emission tomography for target delineation of recurrent glioblastoma in re-irradiation planning.

AIM: To define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET). BACKGROUND: It would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known. MATERIALS AND METHODS: CT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x = 5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study. RESULTS: The sensitivity of CTV-T2 5 mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5 mm and CTV T2 10, 15, or 20 mm. The sensitivity of CTV-Gd 20 mm (97%) was lower than that of CTV-T2 5 mm (98%). CONCLUSIONS: A margin of at least 5 mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning.

Pathological analysis of the surgical margins of resected glioblastomas excised using photodynamic visualization with both 5-aminolevulinic acid and fluorescein sodium.

During glioma resection, 5-aminolevulinic acid (5-ALA) and fluorescein sodium (Fl-Na) are used for photodynamic tumor visualization. The objective of this study was to evaluate the pathological findings of the boundary zone between the tumor and adjacent normal brain in glioblastoma patients undergoing simultaneous double staining with 5-ALA and Fl-Na during surgery. Eight patients received 5-ALA (20 mg/kg orally) before the induction of general anesthesia, and Fl-Na (20 mg/kg) was administered intravenously before the dural incision was performed. The tumor bulk was removed under the guidance of Fl-Na staining alone using conventional white light. Subsequently, residual tumor was removed under the guidance of both fluorescent agents within functionally safe limits until both were visibly undetectable. Twenty specimens exhibiting different staining intensities of both agents were obtained. The vessel index (VI) was calculated from CD31 immunohistochemistry (IHC) samples. Boundary zone tumor cells were detected by IHC for olig2, and were expressed as the olig2 index (OLI). The VI was significantly higher in Fl-Na-positive areas than in Fl-Na-negative areas (p = 0.0005). In contrast, the OLI was significantly higher in 5-ALA-positive areas than in 5-ALA-negative areas (p = 0.0149). 5-ALA-positive/Fl-Na negative areas were observed in 7 patients. These findings indicate that Fl-Na accumulates in areas with a disrupted blood-brain barrier, and that 5-ALA fluorescence is dependent on tumor cell protoporphyrin IX metabolism. In conclusion, 5-ALA was better for detecting tumor cells in the boundary zone than was Fl-Na. Of note, tumor cells existed outside the fluorescence-stained boundaries of both agents.

Usefulness of ¹¹C-methionine positron emission tomography for treatment-decision making in cases of non-enhancing glioma-like brain lesions.

The present study evaluated usefulness of the positron emission tomography with (11)C-methionine for prediction of the clinical course and treatment decision-making in adult patients with newly diagnosed non-enhancing brain lesions mimicking low-grade gliomas. Retrospective analysis was done in 163 cases. In overall, 131 tumors underwent surgical resection, which in 34 cases was done after initial period of observation. Among the latter 5 patients were operated on after significant clinical deterioration. In overall, 3 resected neoplasms corresponded to WHO histopathological grade I, 87 to grade II, 39 to grade III, and 2 to grade IV. In all 163 cases the tumor/normal brain uptake ratio (T/N ratio) of (11)C-methionine ranged from 0.68 to 8.02 (mean 2.21 ± 1.16, median 1.81). Mean T/N ratios of non-operated lesions, low-grade and high-grade tumors were 1.60 ± 0.85, 2.27 ± 1.22, and 2.54 ± 1.09, respectively (P < 0.0001), but overlap between 3 groups was prominent. In patients who had clinical deterioration during the period of observation T/N ratios of the lesion varied from 1.49 to 3.38 (mean 2.23 ± 0.70, median 2.15). Comparison of the deterioration-free survival of patients with T/N ratios of the lesion above and below 1.90 revealed statistically significant difference (P < 0.0001). In conclusion, "wait-and-scan" strategy with delay of surgical treatment does not seem reasonable option if T/N ratio of (11)C-methionine in the non-enhancing glioma-like brain lesion constitutes ≥1.90, since it may be associated with significant risk of tumor progression and clinical deterioration during follow-up.

Infratentorial Pial Arteriovenous Fistula in the Elderly.

BACKGROUND: Intracranial pial arteriovenous fistulas (pAVFs) are rare vascular lesions, which may present with, but are distinct from arteriovenous malformation and dural arteriovenous fistula. They most often manifest during infancy or early childhood, but rarely in adulthood. METHODS: We report an exceptionally rare case of infratentorial pAVF in a 73-year-old man, who presented with progressive gait disturbance due to cerebellar edema resulting from arteriovenous shunts. RESULTS: The patient was successfully treated by endovascular flow reduction followed by surgical extirpation of the fistula. The diagnosis was confirmed by pathological findings. CONCLUSIONS: Pial arteriovenous fistula is rare, but can occur in the elderly. Combination of endovascular flow reduction and surgical disconnection yielded an excellent clinical outcome.

Bevacizumab treatment leads to observable morphological and metabolic changes in brain radiation necrosis.

We investigated morphological and metabolic changes of radiation necrosis (RN) of the brain following bevacizumab (BEV) treatment by using neuroimaging. Nine patients with symptomatic RN, who had already been treated with radiation therapy for malignant brain tumors (6 glioblastomas, 1 anaplastic oligodendroglioma, and 2 metastatic brain tumors), were enrolled in this prospective clinical study. RN diagnosis was neuroradiologically determined with Gd-enhanced MRI and 11C-methionine positron emission tomography (MET-PET). RN clinical and radiological changes in MRI, magnetic resonance spectroscopy (MRS) and PET were assessed following BEV therapy. Karnofsky performance status scores improved in seven patients (77.8 %). Both volumes of the Gd-enhanced area and FLAIR-high area from MRI decreased in all patients after BEV therapy and the mean size reduction rates of the lesions were 80.0 and 65.0 %, respectively. MRS, which was performed in three patients, showed a significant reduction in Cho/Cr ratio after BEV therapy. Lesion/normal tissue (L/N) ratios in MET- and 11C-choline positron emission tomography (CHO-PET) decreased in 8 (89 %) and 9 patients (100 %), respectively, and the mean L/N ratio reduction rates were 24.4 and 60.7 %, respectively. BEV-related adverse effects of grade 1 or 2 (anemia, neutropenia and lymphocytopenia) occurred in three patients. These results demonstrated that BEV therapy improved RN both clinically and radiologically. BEV therapeutic mechanisms on RN have been suggested to be related not only to the effect on vascular permeability reduction by repairing the blood-brain barrier, but also to the effect on suppression of tissue biological activity, such as immunoreactions and inflammation.

Brain activation by music in patients in a vegetative or minimally conscious state following diffuse brain injury.

OBJECTIVE: The aim of this study was to objectively evaluate the brain activity potential of patients with impaired consciousness in a chronic stage of diffuse brain injury (DBI) using functional MRI (fMRI) following music stimulation (MS). METHODS: Two patients in a minimally conscious state (MCS) and five patients in a vegetative state (VS) due to severe DBI were enrolled along with 21 healthy adults. This study examined the brain regions activated by music and assessed topographical differences of the MS-activated brain among healthy adults and these patients. RESULTS: MS was shown to activate the bilateral superior temporal gyri (STG) of both healthy adults and patients in an MCS. In four of five patients in a VS, however, no significant activation in STG could be induced by the same MS. The remaining patient in a VS displayed the same MS-induced brain activation in STG as healthy adults and patients in an MCS and this patient's status also improved to an MCS 4 months after the study. CONCLUSIONS: The presence of STG activation by MS may predict a possible improvement of patients in a VS to MCS and fMRI employing MS may be a useful modality to objectively evaluate consciousness in these patients.

Risk factors affecting third molar autotransplantation during 5 and 10 years.

The aim of this study was to investigate risk factors affecting 5- and 10-year survival in autotransplantation of third molars with complete root formation at dental clinics. Participating dentists were requested to provide information on transplantations performed between 1 January 1990 and 31 December 2009. After data screening and elimination, 183 teeth in 171 men aged 20-72 years (mean, 44.8 years) and 205 teeth in 189 women aged 20-74 years (mean, 42.0 years) were included in the study. A single-factor analysis using the log-rank test revealed that the following factors had a significant influence (p<0.05) on 5-year survival in transplanted teeth in men: recipient site in the maxilla and fewer than 25 present teeth; those for 10-year survival, on the other hand, were recipient site tooth extraction due to periodontal disease, recipient site in the maxilla, fewer than 25 present teeth, and Eichner index Group B1 to C. Cox regression analysis revealed that the odds ratio for 5-year survival for recipient site in the maxilla was 2.873 (95% CI, 1.073-7.695), while that for 10-year survival was 3.713 (95% CI, 1.601-8.609) for recipient site extraction due to periodontal disease, 2.190 (95% CI, 1.021-4.700) for recipient site in the maxilla, and 3.110 (95% CI, 1.470-6.581) for fewer than 25 present teeth. In women, the log-rank test indicated experience of less than 10-year in performing treatment as a significant factor (p <0.05) in 5-year survival. These results suggest that medium-term survival in transplanted teeth is influenced by operational risk factors in women, while long-term survival in transplanted teeth is influenced by individual oral status in men.

Spastic Muscle Overactivity in a Patient With a Chronic Disorder of Consciousness After Severe Traumatic Brain Injury Successfully Treated with Acupuncture: A Case Report.

Spastic muscle overactivity (SMO) is a frequent retractable complication in patients with prolonged disorder of consciousness (DOC) after severe traumatic brain injury (sTBI). Here, we describe a patient with DOC and SMO after sTBI successfully treated with adjunctive acupuncture. A woman in her 70s with chronic DOC, corresponding to a minimally conscious state (MCS), and limb SMO after severe TBI due to a traffic accident was admitted to our hospital six months after the injury and received multiple care interventions including physiotherapy and nurse care. However, her SMO in the extremities with decorticated posture, in which bilateral elbow joints were flexed and bilateral knee joints were extended, remained. The passive range of motion (ROM) of bilateral elbow joints decreased. Her DOC also remained in MCS. Thus, acupuncture was implemented twice weekly for 20 weeks to improve SMO and promote arousal 30 months after injury. Modified Tardieu scale (MTS) during right elbow extension was measured before and after each acupuncture session. The maximum passive ROM (MTS-R2) gradually increased during the acupuncture period. The catch angle (MTS-R1), which indicates the influences of the hyper stretch reflex, also gradually reduced. The ROM limitation and the catch angle trended to decrease immediately after each acupuncture session. Ultrasound shear-wave elastography of the right brachial biceps muscle (BBM) at the 28th acupuncture session showed a reduction of shear-wave speeds immediately after the session, indicating that acupuncture reduced BBM stiffness. Her DOC state remained MCS. In the presented case, the adjunctive acupuncture therapy reduced SMO after severe TBI. Acupuncture may be beneficial for such patients. A large cohort study is warranted to confirm the effects of acupuncture on SMO in patients with DOC after sTBI.

Posttraumatic epilepsy in chronic disorders of consciousness due to severe traumatic brain injury after traffic accidents.

PURPOSE: To evaluate the clinical state of posttraumatic epilepsy (PTE) in patients with chronic disorders of consciousness (CDC) due to severe traumatic brain injury (STBI) after traffic accidents and clarify the risk factors for seizure occurrence in such patients. METHODS: Two hundred ninety-three patients with CDC due to STBI (mean age at admission [±standard deviation]: 36.4 ± 17.9 years; men: 71.7 %; mean duration of injury to admission: 416 ± 732 days; mean hospitalization time: 899 ± 319 days) were enrolled in this study. We retrospectively investigated the relationship between seizure conditions (type and frequency) and clinical data, including age, sex, pathological types of brain injury, with/without surgical intervention, degree of CDC, and administration of antiseizure medications (ASMs). RESULTS: Overall, 52.9 % (n = 155/293) and 64.2 % of the patients (n = 183/of 285 patients surviving at discharge) were administered ASMs at admission and discharge, respectively. One hundred thirty-two patients (45.1 %) experienced epileptic seizures during hospitalization, and the mean seizure frequency was 4.0 ± 0.4 times per year. In multivariate analysis, significant and independent risk factors of seizure occurrence were revealed to be male sex, high National Agency for Automotive Safety and Victims' Aid score, hypoxic encephalopathy, and history of the neurosurgical operations. CONCLUSION: The high prevalence of PTE in patients with CDC due to STBI, and the significant and independent risk factors for seizure occurrence in the chronic clinical phase were revealed. We expect that this study will aid toward improving clinical assessment and management of epileptic seizures in the population.

Predicting Isocitrate Dehydrogenase Status in Non-Contrast-Enhanced Adult-Type Astrocytic Tumors Using Diffusion Tensor Imaging and 11C-Methionine, 11C-Choline, and 18F-Fluorodeoxyglucose PET.

We aimed to differentiate the isocitrate dehydrogenase (IDH) status among non-enhanced astrocytic tumors using preoperative MRI and PET. We analyzed 82 patients with non-contrast-enhanced, diffuse, supratentorial astrocytic tumors (IDH mutant [IDH-mut], 55 patients; IDH-wildtype [IDH-wt], 27 patients) who underwent MRI and PET between May 2012 and December 2022. We calculated the fractional anisotropy (FA) and mean diffusivity (MD) values using diffusion tensor imaging. We evaluated the tumor/normal brain uptake (T/N) ratios using 11C-methionine, 11C-choline, and 18F-fluorodeoxyglucose PET; extracted the parameters with significant differences in distinguishing the IDH status; and verified their diagnostic accuracy. Patients with astrocytomas were significantly younger than those with glioblastomas. The following MRI findings were significant predictors of IDH-wt instead of IDH-mut: thalamus invasion, contralateral cerebral hemisphere invasion, location adjacent to the ventricular walls, higher FA value, and lower MD value. The T/N ratio for all tracers was significantly higher for IDH-wt than for IDH-mut. In a composite diagnosis based on nine parameters, including age, 84.4% of cases with 0-4 points were of IDH-mut; conversely, 100% of cases with 6-9 points were of IDH-wt. Composite diagnosis using all parameters, including MRI and PET findings with significant differences, may help guide treatment decisions for early-stage gliomas.

Survival rate in autotransplanted premolars with complete root formation: a retrospective clinical survey.

The purpose of this study was to analyze the survival rate in autotransplanted premolars with complete root formation in dental clinics. Participating dentists were requested to provide information on transplantations they had undertaken between 1 January 1990 and 31 December 2010. Data on a total of 708 teeth from 637 patients were collected. Data for other tooth types and for teeth with incomplete root formation were eliminated. In this study, data on 40 teeth in 35 patients were analyzed. Participants consisted of 17 men and 18 women ranging from 24 to 79 years in age (mean age, 43.7 years). The cumulative survival rate was 100% at the 5-year mark and 72.7% at 10 years, as calculated by the Kaplan-Meier method. Single-factor analysis revealed that "transplanted to the molar regions" was a significant risk factor (p<0.05) influencing the survival of transplanted teeth. However, a Cox regression analysis showed no significance. The results of this study suggest that, in cases where there is a suitable donor tooth and the oral condition is good, premolar autotransplantation is a viable treatment option, even when there is complete root formation in the donor teeth.

Procedures for treating spaces vacated by loss of transplanted teeth.

The main reasons for loss of autotransplanted teeth are different from those involved in natural teeth loss. The aim of this study was to investigate which procedures were employed to treat spaces vacated when autotransplanted teeth were lost. Participating dentists were requested to provide information on transplantations they had undertaken. A total of 614 teeth in 552 patients (37 dentists) ranging in age from 17 to 79 years (mean age: 44.1 years) were examined. A total of 102 transplanted teeth were lost during the observation period. Procedures for treatment of spaces vacated were not influenced by main reason for transplanted tooth loss. The procedure used to treat depended on the original prosthodontic treatment of the transplanted teeth. For single crowns, the spaces were left empty (33.9%) or replaced by bridge work (30.5%), implants (20.3%), or dentures (10.2%). For single crowns in the upper and lower second molar regions, the spaces were usually left empty (upper 100%, lower 71.4%), while for those in the upper and lower first molar regions, the spaces were often replaced by bridge work (upper 41.7%, lower 50.0%). For bridge abutments, spaces were replaced by dentures (42.9%), implants (33.3%), or left empty (14.3%), and in the lower second molar region, they were mostly replaced by implants (5 cases, 41.7%). For most denture abutment cases, the spaces were replaced by dentures (88.9%). During the survival period of the transplanted teeth, the masticatory burden on the other teeth is reduced and the adjacent teeth are supported by the transplanted tooth. Even if transplanted teeth are eventually lost, traditional procedures can be performed to fill the vacated space.

Brainstem volume, diffusion, and metabolism are associated with chronic consciousness disorders after traumatic brain injury.

BACKGROUND AND PURPOSE: We aimed to identify reliable neuroradiological features of the brainstem reflecting the neurological symptoms of patients with chronic disorders of consciousness (DOCs) due to severe traumatic brain injury (TBI). METHODS: We retrospectively examined 86 patients with chronic DOCs due to severe TBI caused by automobile accidents. We studied the relationships among (1) neurological symptoms, including consciousness level, (2) integrated cognitive/physical condition, and (3) neuroradiological features of the brainstem (brainstem volume on MRI, fractional anisotropy [FA] value in the brainstem, and standardized uptake value [SUV] of 18F-fluorodeoxyglucose [FDG] on positron emission tomography in the brainstem). RESULTS: Brainstem volume was significantly larger and FA values were significantly higher in patients with a better level of consciousness. However, brainstem volumes were significantly decreased and the maximum SUV (SUVmax ) of FDG significantly increased at 2 years following admission regardless of the level of consciousness at admission. The brainstem volume was significantly larger and the FA value and SUVmax of FDG were significantly higher in patients with better National Agency for Automotive Safety and Victims' Aid (NASVA) scores at admission. The decrease in the brainstem volume was significantly minimized and the SUVmax of FDG significantly increased in patients with more improvement in the NASVA score 2 years after admission. CONCLUSIONS: The volume, FA value, and SUVmax of FDG of the brainstem are important neuroradiological features associated with the neurological conditions of patients with chronic DOCs due to severe TBI.

Methionine-PET to differentiate between brain lesions appearing similar on conventional CT/MRI scans.

BACKGROUND AND PURPOSE: 11 C-Methionine (MET)-PET is a useful tool in neuro-oncology. This study aimed to examine whether a combination of diagnostic variables associated with MET uptake could help distinguish between brain lesions that are often difficult to discriminate in conventional CT and MRI. METHODS: MET-PET was assessed in 129 patients with glioblastoma multiforme, primary central nervous lymphoma, metastatic brain tumor, tumefactive multiple sclerosis, or radiation necrosis. The accuracy of the differential diagnosis was analyzed using five diagnostic characteristics in combination: higher maximum standardized uptake value (SUV) of MET in the lesion/the mean normal cortical SUV of MET ratio, overextension beyond gadolinium, peripheral pattern indicating abundant MET accumulation in the peripheral region, central pattern denoting abundant MET accumulation in the central region, and dynamic-up suggesting increased MET accumulation during dynamic study. The analysis was conducted on sets of two of the five brain lesions. RESULTS: Significant differences in the five diagnostic traits were observed among the five brain lesions, and differential diagnosis could be achieved by combining these diagnostic features. The area under the curve between each set of two of the five brain lesions using MET-PET features ranged from .85 to 1.0. CONCLUSIONS: According to the findings, combining the five diagnostic criteria could help with the differential diagnosis of the five brain lesions. MET-PET is an auxiliary diagnostic technique that could help in distinguishing these five brain lesions.