Zero Echo Time Magnetic Resonance Imaging; Techniques and Clinical Utility in Musculoskeletal System.

Zero echo time (ZTE) sequence is recent advanced magnetic resonance technique that utilizes ultrafast readouts to capture signals from short-T2 tissues. This sequence enables T2- and T2* weighted imaging of tissues with short intrinsic relaxation times by using an extremely short TE, and are increasingly used in the musculoskeletal system. We review the imaging physics of these sequences, practical limitations, and image reconstruction, and then discuss the clinical utilities in various disorders of the musculoskeletal system. ZTE can be readily incorporated into the clinical workflow, and is a promising technique to avoid unnecessary radiation exposure, cost, and time-consuming by computed tomography in some cases. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 1.

Development of an 123I-metaiodobenzylguanidine Myocardial Three-Dimensional Quantification Method for the Diagnosis of Lewy Body Disease.

OBJECTIVES: We recently developed a new uptake index method for 123I-metaiodobenzylguanidine (123I-MIBG) heart uptake measurements by using planar images (radioisotope angiography and planar image) for the diagnosis of Lewy body disease (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). However, the diagnostic accuracy of the uptake index was approximately equal to that of the heart-to-mediastinum ratio (H/M) for the discrimination of the LBD and non-LBD patients. A simple and pain-free uptake index method using 123I-MIBG SPECT images by modifying the uptake index method may show better diagnostic accuracy than the planar uptake index method. We hypothesized that the development of a new uptake index method for the determination of 123I-MIBG using single-photon emission computed tomography (SPECT) imaging would provide a reliable and reproducible diagnostic tool for clinical application. Regarding this, the purpose of this study was to develop a new uptake index method with a simple protocol to determine 123I-MIBG uptake on SPECT. METHODS: The 123I-MIBG input function was determined from the input counts of the pulmonary artery, assessed by analyzing the pulmonary artery time-activity curves. The 123I-MIBG output function was obtained from 123I-MIBG SPECT counts on the polar map. The uptake index was calculated through dividing the output function by the input function (SPECT uptake method). For the purpose of the study, 77 patients underwent 123I-MIBG SPECT, with an average of 31.5 min after clinical assessment and injection of the tracer. The H/M values, as well as planar and SPECT uptake indices were calculated, and then correlated with clinical features. RESULTS: According to the results, values obtained for LBD were significantly lower than those for non-LBD in all analyses (P<0.01). The overlap of the H/M values between the LBD and non-LBD cases ranged from 2.06 to 2.50. Furthermore, the overlap in uptake index values between LBD and non-LBD cases in planar image analysis was 1.05-1.29. The SPECT uptake index method showed the least overlap of 1.23-1.25, with the highest value for LBD patients clearly distinguished from the lowest value for the non-LBD patients. CONCLUSION: The new 123I-MIBG SPECT quantification method, developed by the input counts of the pulmonary artery, clearly distinguished LBD from non-LBD. Therefore, this method may be appropriate for routine clinical study.

Uptake Index of 123I-metaiodobenzylguanidine Myocardial Scintigraphy for Diagnosing Lewy Body Disease.

OBJECTIVES: Iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy has been used to evaluate cardiac sympathetic denervation in Lewy body disease (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). The heart-to-mediastinum ratio (H/M) in PD and DLB is significantly lower than that in Parkinson's plus syndromes and Alzheimer's disease. Although this ratio is useful for distinguishing LBD from non-LBD, it fluctuates depending on the system performance of the gamma cameras. Therefore, a new, simple quantification method using 123I-MIBG uptake analysis is required for clinical study. The purpose of this study was to develop a new uptake index with a simple protocol to determine 123I-MIBG uptake on planar images. METHODS: The 123I-MIBG input function was obtained from the input counts of the pulmonary artery (PA), which were assessed by analyzing the PA time-activity curves. The heart region of interest used for determining the H/M was used for calculating the uptake index, which was obtained by dividing the heart count by the input count. RESULTS: Forty-eight patients underwent 123I-MIBG chest angiography and planar imaging, after clinical feature assessment and tracer injection. The H/M and 123I-MIBG uptake index were calculated and correlated with clinical features. Values for LBD were significantly lower than those for non-LBD in all analyses (P<0.001). The overlapping ranges between non-LBD and LBD were 2.15 to 2.49 in the H/M method, and 1.04 to 1.22% in the uptake index method. The diagnostic accuracy of the uptake index (area under the curve (AUC), 0.98; sensitivity, 96%; specificity, 91%; positive predictive value (PPV), 90%; negative predictive value (NPV), 93%; and accuracy, 92%) was approximately equal to that of the H/M (AUC, 0.95; sensitivity, 93%; specificity, 91%; PPV, 90%; NPV, 93%; and accuracy, 92%) for discriminating patients with LBD and non-LBD. CONCLUSION: A simple uptake index method was developed using 123I-MIBG planar imaging and the input counts determined by analyzing chest radioisotope angiography images of the PA. The diagnostic accuracy of the uptake index was approximately equal to that of the H/M for discriminating patients with LBD and non-LBD.

Distribution of cerebello-olivary degeneration in idiopathic late cortical cerebellar atrophy: clinicopathological study of four autopsy cases.

Late cortical cerebellar atrophy (LCCA) is a neurodegenerative disease which presents with slowly progressive cerebellar ataxia as a prominent symptom and is characterized neuropathologically by a limited main lesion to the cerebellar cortex and inferior olivary nucleus. To elucidate the features of lesions in the cerebellar cortex and inferior olivary nucleus, four autopsy cases suffering from idiopathic LCCA without other cortical cerebellar atrophies, such as alcoholic cerebellar degeneration, phenytoin intoxication, or hereditary cerebellar atrophy including spinocerebellar ataxia type 6, were examined. All affected patients had identical distinct features of cerebellar cortical lesions. In all four cases, the most obvious pathological finding throughout the cerebellum was loss of Purkinje cells, but the rarefaction of granular cell layers was observed only where loss of Purkinje cells was very severe, and thinning of the molecular layer was seen only where the rarefaction of granular cell layers was moderate to severe. Two patients presented with vermis dominant cerebellar cortical lesions, but the other two patients showed hemispheric dominant pathological changes. Neuronal loss of the inferior olivary nucleus was observed in the three autopsy cases. Two of the three cases had a prominent lesion in the dorsal part of the inferior olive and the cerebellar cortical lesion disclosed the vermis dominance, but the other patient, showing prominent neuronal loss in the ventral olivary nucleus, had a cerebellar hemisphere dominant lesion. The patient without neuronal loss in the inferior olivary nucleus had suffered from a shorter period of disease than the others and the rarefaction of granular cell layers and narrowing of the molecular layer of the cerebellar cortex were mild. Therefore, it is obvious that there are two types of cerebellar cortex lesions in idiopathic LCCA; one is vermis dominant and the other is cerebellar hemispheric dominant. The lesion of the inferior olivary nucleus occurs as a secondary degeneration after rarefaction of the granular cell layer and thinning of the molecular layer of the cerebellar cortex progresses. Furthermore, the distribution of the degeneration in the inferior olivary nucleus depends on the distribution of the cerebellar cortex lesions.

[An autopsy case of miliary brain metastases].

A 57-year-old man was admitted to our hospital with a diagnosis of psychiatric emergency. His symptoms were similar to encephalitis, metabolic encephalopathy or acute depressive psychosis because of poor focal neurological signs. Laboratory examinations, including routine hematological and biochemical investigations, serum vitamin B1 B12 levels, and cerebrospinal fluid obtained by lumbar puncture, were normal. Brain CT was also normal, therefore it was difficult to make a diagnosis. But, we could clinically diagnose him as having pulmonary adenocarcinoma with numerous metastatic nodules of the brain. Because miliary lesions in the cerebral hemispheres, brainstem and cerebellum were disclosed on brain MRI. Furthermore, chest CT revealed the lung tumor in the left S8 area. In addition, laboratory examination showed a rise of tumor marker and cytologic examination of sputum revealed class V. Fluid-attenuated inversion recovery and contrast-enhanced MR images demonstrated more prominently miliary metastases, in particular lesions in the cerebral cortex, than T1- and T2-weighted images. There was neither edema in the surrounding region of metastatic nodules nor mass effect on all MR images. Spinal MRI showed no metastatic lesions. The patient died of respiratory failure at the age of 58, about eight months after the disease onset. The brain weighed 1,575 g. Neuropathological findings revealed diffuse miliary brain metastases located in all parts of the brain, except for the medulla oblongata. Histological examination disclosed multiple metastases from a well-differentiated adenocarcinoma with a predominant tubular pattern. There was neither edema nor glial reaction in the surrounding area of metastatic lesions. Many pseudorosettes were recognized and carcinoma cells, extending through perivascular spaces into the subarachnoid space, were noticed.

[Cerebral small infarcts of the precentral and postcentral gyri presenting with unilateral monoataxia: a report of two cases].

Two cases of unilateral monoataxia, due to small infarcts in the precentral and postcentral gyri, were reported. A 76-year-old man (case 1), and a 90-year-old woman (case 2) suddenly developed clumsiness of the left upper extremity. Neurological examination revealed cerebellar ataxia in the left upper extremity in both cases. But, the other abnormal neurological findings, including the muscle weakness, abnormal muscle tone, and proprioceptive deficit, were not noted. In case 2, cerebellar ataxia disappeared about ten days after the onset of the disease. On the other hand, ataxia of case 1 remained about two months after the disease onset. Brain magnetic resonance imaging (MRI) of cases 1 and 2, showed small infarcts at the border between the right precentral gyrus and postcentral gyrus. In addition, brain MRI of case 1 disclosed another infarcts in the just medial portion of the precentral knob and the centrum semiovale of central region, respectively. It was suggested that the mechanism of cerebellar ataxia caused by infarct in the central region, was not only due to the interruption of two distinctive neuronal pathways, including the corticopontine tract and cerebellothalamocortical tract, but also due to the disturbance of sensory-motor integrity. In conclusion, etiologies of unilateral monoataxia may be heterogeneous. Furthermore, functional outcome may depend on the mechanism of unilateral monoataxia.

"Forme fruste" of amyotrophic lateral sclerosis with dementia: a report of five autopsy cases without dementia and with ubiquitinated intraneuronal inclusions.

We clinicopathologically investigated five autopsy cases of ALS without dementia and with ubiquitinated intraneuronal inclusions. The age at onset of symptoms ranged from 52 to 81 years and the duration of the disease was from 10 months to 3 years, 3 months. All five patients initially developed lower motor neuron signs, including bulbar signs, and upper motor neuron signs were found in the middle to late clinical stages, but dementia was not observed in all five cases. Thus, the clinical diagnoses of all five patients were ALS without dementia. Neuropathological examination of all five cases revealed not only obvious degeneration of upper motor neurons with neuronal loss of Betz cells, but also lower motor neuron involvement associated with Bunina bodies. In addition, ubiquitin-immunoreactive intraneuronal inclusions in the hippocampal dentate granular cells and degeneration of the substantia nigra were observed in all five cases. Furthermore, neuronal loss with astrocytosis in the dorsomedial portion of the anterior first temporal gyrus was observed in all three cases in which this structure was examined. Neuronal loss with astrocytosis in the subiculum was found in four cases. Neuronal loss of the parahippocampal gyrus was observed in three of the five autopsy cases, and amygdala involvement was encountered in three of four cases in which this structure was investigated. Based on these clinicopathological findings and a review of the published literature, we concluded that our five cases were ALS without dementia, but with pathological hallmarks compatible with ALS with dementia. We also concluded that there is a "forme fruste" of ALS with dementia showing no overt dementia clinically.

[Pure akinesia presenting with antecollis].

We reported a 77-year-old woman having pure akinesia who presented with antecollis induced by L-threo-3, 4-dihydroxyphenylserine (L-DOPS). At the age of 70, she noticed increasing difficulty in standing up from a seat and moving. Afterward, she developed gait disturbance with difficulty in initiating walking, frozen gait, and postural instability. At 73 years of age, she came to our hospital, because she gradually fell down easily. Neurological examination disclosed mild akinesia with freezing symptom and kinésie paradoxale. No evidence of dementia, supranuclear gaze palsy, pseudobulbar palsy, rigidity, or tremor were present. As she developed akinesia, of which L-dopa therapy achieved little improvement, we clinically diagnosed as having pure akinesia. At age 74, L-DOPS was administered at a dose of 300mg per day and gradually increased up to 900mg per day, because her postural reflex was markedly disturbed and gait showed severe unsteadiness. Amelioration of frozen gait and unsteadiness were recognized, but efficacy of L-DOPS was temporal. It is well known that reported cases of pure akinesia were pathologically diagnosed as having progressive supranuclear palsy (PSP) or pallido-nigro-luysian atrophy. Therefore, the present case was suspected as having pathological changes which involved degeneration of the substantia nigra and globus pallidus. After three years of treatment with L-DOPS, at age 77, she was admitted to our hospital for abrupt onset of her dropped head. Hematological examinations were normal, cervical MRI showed no evidence of paracervical muscular atrophy, and electromyography did not demonstrate any abnormal change. In addition, her posterior cervical muscles showed abnormally high tension, so the dropped head was considered due to antecollis. After admission, antecollis disappeared rapidly following discontinuation of L-DOPS. However the mechanism of drug induced dystonia is imperfectly understood on the basis of the clinical course, L-DOPS was considered as possible cause of her antecollis. L-DOPS, artificial precursor of noradrenarine (NA), is thought to increase not only NA level in the CNS, but also inhibit release of acetylcholine. It is suggested that the antecollis of present case results from impairment of a normal dopaminergic-noradorenergic balance caused by increased NA and striatal dopamine deficiency. This is the first case of antecollis induced by L-DOPS in a pure akinesia patient, providing important information on mechanism of drug induced dystonia and indicating caution in the clinical use of L-DOPS.

[An autopsy case of dementia lacking distinctive histology showing semantic dementia].

We report an autopsy case of dementia lacking distinctive histology (DLDH) showing semantic dementia. At age 47, a Japanese man developed aspontaneity, followed by semantic dementia a few months after the onset. Thereafter he developed disinhibition and the language disturbance, which progressed transcortical sensory aphasia and terminally mixed transcortical aphasia. At age 48, about 10 months after the disease onset, neurological examination revealed frontal signs and hyperreflexia in the four extremities and 4 months later, the patient presented with mild rigidity in the right upper and lower extremities. At age 49, 1 year and 8 months after the onset of the disease, he could not walk by himself. At age 50, 2 years and 8 months after the onset, he died of pneumonia. The brain weighed 1350 g. Macroscopically, atrophy of the frontal lobes and temporal lobes, predominant in the left, was evident. The caudate nucleus was severely atrophic, in addition to the depigmentation of the substantia nigra. Neuronal loss and astrocytosis was obvious in the cerebral cortex, prominently in the frontotemporal lobes, amygdala, caudate nucleus, putamen, pallidum, thalamus, and substantia nigra. In the caudate nucleus, prominent neuronal loss with fibrillary gliosis was obvious. Senile plaques, neurofibrillary tangles, Pick bodies, astrocytic plaques, and tufted astrocytes were not found by Gallyas and tau staining. Ubiquitin-immunoreactive intracytoplasmic inclusions were not encountered in the hippocampal dentate gyrus and superficial layers in the frontotemporal cortex. On the basis of meticulous perusal of the literature, we believe that our case is the first autopsy case of DLDH reported in Japan.

[A trial of biweekly paclitaxel administration in consideration of QOL for advanced or recurrent gynecologic cancer].

At present there is no oral medicine available which is effective for advanced or recurrent case of elderly patients with gynecologic cancer. We report that a low-dose biweekly paclitaxel administration preserves quality of life (QOL) and seems to be "tumor dormancy like" therapy of good compliance with few side effects. A total of 11 cases were in ovarian cancer (5), uterine cancer (3), cervical cancer (2), and uterine sarcoma (1). The median age was 68 years old and the age range was 50 to 79 years old. We performed a standard treatment as a first time treatment. Afterwards, we obtained complete informed consent from the patients for progressive or recurrent cancer and administered biweekly paclitaxel 70 mg/m2 (80-100 mg/body) on an outpatient basis. We reviewed the effect, side effect and compliance of the medication. We judged the side effect based on the Japanese cancer treatment society common toxicity criteria. The result was only one patient death from PD and the other 10 patients were PR or a state of NC without side effect. An ovary cancer case patient lived for 67 months at best, an endometrial cancer case patient lived for 62 months at best, a cervical cancer case patient lived for 74 months at best, and a recurrent uterine sarcoma case patient lived for 76 months after recurrence and the QOL was good. In addition, there was no onset of side effect more than grade 2 in all of the cases and a compliance of medical administration was good. In these cases, we thought that a low-dose of biweekly paclitaxel administration was regarded as a therapy to preserve QOL without a serious side effect and a good compliance of medication. Furthermore, we intend to increase more cases and would like to report them in the future.

A novel L266V mutation of the tau gene causes frontotemporal dementia with a unique tau pathology.

We report a novel mutation of tau (L266V missense mutation in exon 9) which may cause a type of familial frontotemporal dementia. The brain of a patient showed Pick body-like inclusions and unique tau-positive, argyrophilic astrocytes with stout filaments and naked, round, or irregular argyrophilic inclusions with deposits of both three-repeat and four-repeat tau. Recombinant tau with a L266V mutation showed a reduced ability to promote microtubule assembly, which may be the primary effect of the mutation.