Mariko Yoshida

A preliminary diffusional kurtosis imaging study of Parkinson disease: comparison with conventional diffusion tensor imaging

IntroductionDiffusional kurtosis imaging (DKI) is a more sensitive technique than conventional diffusion tensor imaging (DTI) for assessing tissue microstructure. In particular, it quantifies the microstructural integrity of white matter, even in the presence of crossing fibers. The aim of this preliminary study was to compare how DKI and DTI show white matter alterations in Parkinson disease (PD).MethodsDKI scans were obtained with a 3-T magnetic resonance imager from 12 patients with PD and 10 healthy controls matched by age and sex. Tract-based spatial statistics were used to compare the mean kurtosis (MK), mean diffusivity (MD), and fractional anisotropy (FA) maps of the PD patient group and the control group. In addition, a region-of-interest analysis was performed for the area of the posterior corona radiata and superior longitudinal fasciculus (SLF) fiber crossing.ResultsFA values in the frontal white matter were significantly lower in PD patients than in healthy controls. Reductions in MK occurred more extensively throughout the brain: in addition to frontal white matter, MK was lower in the parietal, occipital, and right temporal white matter. The MK value of the area of the posterior corona radiata and SLF fiber crossing was also lower in the PD group.ConclusionDKI detects changes in the cerebral white matter of PD patients more sensitively than conventional DTI. In addition, DKI is useful for evaluating crossing fibers. By providing a sensitive index of brain pathology in PD, DKI may enable improved monitoring of disease progression.

Inguinal hernia repair in children using single-incision laparoscopic-assisted percutaneous extraperitoneal closure

BACKGROUND/PURPOSE There are numerous techniques of minimally invasive surgery for pediatric inguinal hernia. However, laparoscopic percutaneous extraperitoneal closure (LPEC) is one of the most simple and reliable methods. Single-incision laparoscopic surgery has recently been developed to reduce the invasiveness of traditional laparoscopy. This study aimed to assess the safety and feasibility of the single-incision approach for LPEC. MATERIALS AND METHODS Between June 2009 and March 2010, 117 conventional LPEC and 60 single-incision LPEC (SILPEC) procedures were performed. A laparoscope was placed through a transumbilical incision. A 3-mm grasping forceps was inserted in the lower abdomen in LPEC and through the same transumbilical incision with a different entrance in SILPEC. Using the LPEC needle, the hernia sac was closed extraperitoneally. We compared the short-term outcomes of 177 children operated on using either technique. RESULTS Visualization and tissue manipulation were good in both methods. There were no complications or evidence of early recurrence. Cosmetically, SILPEC proved to be superior to LPEC because the scar resulting from surgical incision is hidden within the umbilicus. CONCLUSION Single-incision LPEC proved to be as successful an operative procedure as LPEC and produced excellent cosmetic results. Single-incision LPEC for inguinal hernia in children is safe and feasible.

Utilization of diffusion tensor tractography in combination with spatial normalization to assess involvement of the corticospinal tract in capsular/pericapsular stroke: Feasibility and clinical implications.

To investigate the feasibility of using spatial normalization in combination with diffusion tensor (DT) corticospinal tractography to assess corticospinal tract (CST) involvement in capsular or pericapsular stroke.

NUT midline carcinoma: report of 2 cases suggestive of pulmonary origin.

In this study, we report 2 pediatric cases of nuclear protein of the testis (NUT) midline carcinoma (NMC) suggestive of pulmonary origin: case 1 was a 14-year-old Japanese boy and case 2 was a 7-year-old Japanese girl. Initial symptoms of both cases were prolonged cough and chest pain, and the case 2 patient also complained of lumbago and lumbar mass due to bone metastases. Imaging studies revealed that pulmonary tumors from both patients were located at the hilar region of the lower lobe. Biopsies of the tumors showed undifferentiated carcinoma in case 1 and combined undifferentiated and squamous cell carcinoma in case 2. Despite intensive treatment with chemotherapy and radiation, progression of neither tumor was controlled, and both patients died of the tumors at 1 year (case 1) and 4 months (case 2) after onset of disease. Both tumors were diffusely positive for p63 and NUT expression and were partially positive for various cytokeratins. Reverse transcription polymerase chain reaction analysis and subsequent direct sequencing revealed that the bromodomain-containing protein 4-NUT chimeric gene was present in tumor tissue of both patients, leading to a diagnosis of NMC. The tumor cells of case 1 were also positive for thyroid transcription factor-1 expression, but those of case 2 were negative. Histologic examination of the surgically removed lung tumor of case 1 indicated that the origin of the tumor was basal cells of the bronchiolar epithelia.

Diffusion tensor tract-specific analysis of the uncinate fasciculus in patients with amyotrophic lateral sclerosis

IntroductionThe uncinate fasciculus (UF) consists of core fibers connecting the frontal and temporal lobes and is considered to be related to cognitive/behavioral function. Using diffusion tensor tractography, we quantitatively evaluated changes in fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) of the UF by tract-specific analysis to evaluate the damage of the UF in patients with amyotrophic lateral sclerosis (ALS).MethodsWe obtained diffusion tensor images of 15 patients with ALS and 9 age-matched volunteers.ResultsPatients with ALS showed significantly lower mean FA (P = 0.029) compared with controls. No significant difference was seen in mean ADC.ConclusionThe results suggest that damage of the UF in patients with ALS can be quantitatively evaluated with FA.

Residual fistula after laparoscopically assisted anorectoplasty: is it a rare problem?

PURPOSE Although various urologic complications have been reported after abdominoperineal pull-through and posterior sagittal anorectoplasty for the treatment of high-type imperforate anus, reports regarding complications after laparoscopically assisted anorectoplasty (LAARP) are surprisingly rare. Here, we discuss the potential complications of LAARP. METHODS A retrospective study was conducted of 24 patients treated with LAARP from 2000 to 2006. The clinical and operative records were reviewed. Of the 24 patients, 18 were evaluated postoperatively by screening magnetic resonance imaging (MRI). RESULTS The 24 participants are composed of patients with rectoprostatic urethral fistula (n = 15), rectal agenesis (n = 3), rectovesical fistula (n = 2), rectovaginal fistula (n = 2), and cloaca (n = 2). Defecatory function after LAARP was satisfactory. None of the patients had dysuria or urinary infection postoperatively. Cystic formations posterior to the urethra were demonstrated in 9 of the 18 cases examined by MRI. Postoperative voiding cystourethrography failed to demonstrate the lesion in 6 of 9 patients. The types of imperforate anus in this subgroup were rectoprostatic urethral fistula (n = 7), rectovesical fistula (n = 1), and rectal agenesis without fistula (n = 1). Average cyst diameter was 22 +/- 19 mm. Two patients with large cysts (62 and 42 mm) underwent surgical resection. CONCLUSIONS Although satisfactory fecal continence could be achieved by LAARP, we experienced 2 cases with a large residual fistula that required surgical resection. In addition, screening MRI demonstrated the presence of cystic formations in 9 of 18 patients. We recommend that MRI be performed routinely during follow-up of patients treated with LAARP.

Tract-specific analysis of the superior occipitofrontal fasciculus in schizophrenia

Diffusion tensor imaging has been highlighted as a non-invasive tool to explore neural connectivity in vivo. Several studies have suggested disorganization of the neural network (circuitry) including the thalamo-prefrontal connection in schizophrenia. Recent research using post-mortem brains showed that the superior occipitofrontal fasciculus (SOFF) fibers extended to the thalamus. We postulated that the SOFF has some relationship with the anatomical structural components of the thalamo-prefrontal circuitry. We quantitatively assessed the diffusion abnormalities of the SOFF using diffusion tensor tractography (DTT) in schizophrenia. Nineteen male patients with schizophrenia and 20 age-matched normal controls were studied. DTT of the SOFF (DTT-SOFF) was visualized using free software (dTV II/VOLUME-ONE), and we performed tract-specific measurement of the fractional anisotropy (FA), then calculated the apparent diffusion coefficient (ADC) of the DTT-SOFF. Tractography and tract-specific analysis of the SOFF were successfully performed in all subjects. All tracts appeared to be connecting the prefrontal area to the thalamus. The mean FA value of patients with schizophrenia [0.376 (S.D. 0.030)] was significantly lower than that of controls [0.432 (S.D. 0.032)], and the ADC value of patients with schizophrenia [0.771 (x10(-3) mm(2)/s) (S.D. 0.041)] was significantly higher than that of controls [0.726 (x10(-3) mm(2)/s) (S.D. 0.027)]. Our results suggest that the so-called SOFF may be a structural component connecting the prefrontal area to the thalamus and that it is deteriorated in schizophrenia.

Laparoscopic spleen-preserving distal pancreatectomy for solid pseudopapillary tumor with conservation of splenic vessels in a child

Laparoscopic spleen-preserving distal pancreatectomy (LSDP) with conservation of the splenic vessels is gaining acceptance as a reliable treatment for selected patients with low-grade malignant tumors of the pancreas in adults. The operation requires advanced laparoscopic skills to safely divide the fine branches of the splenic vessels. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels is rarely reported in children. We describe a 12-year-old girl with solid pseudopapillary tumor in the body of the pancreas that was successfully treated with LSDP, preserving the splenic vessels. The postoperative course was uneventful, and the functional and aesthetic results were satisfactory. Laparoscopic spleen-preserving distal pancreatectomy with conservation of splenic vessels may be a safe and feasible treatment option for children with pancreatic disease.

Development of bilateral wearable device “kento” for control robots using muscle actuator modules

A method of giving intelligence to control robots by human navigations is one of appropriate solution to respond to a lot of unforeseeable situations, and making movement of complicated robots in contact condition with surroundings is not easy. In this research, a bilateral wearable device using stiffness adjustable muscle actuator modules is developed in order to control robots, feel external force of robots and teach motion that contact on surroundings. For an experiment it was realized maneuvering a musculo-skeletal humanoid, it could feedback humanoids external force to manipulator and its force feedback by bilateral control leads manipulator to do safety contact motion.

Assessing Blood Flow in an Intracranial Stent: A Feasibility Study of MR Angiography Using a Silent Scan after Stent- Assisted Coil Embolization for Anterior Circulation Aneurysms

BACKGROUND AND PURPOSE: Blood flow in an intracranial stent cannot be visualized with 3D time-of-flight MR angiography owing to magnetic susceptibility and radiofrequency shielding. As a novel follow-up tool after stent-assisted coil embolization, we applied MRA by using a Silent Scan algorithm that contains an ultrashort TE combined with an arterial spin-labeling technique (Silent MRA). The purpose of this study was to determine whether Silent MRA could visualize flow in an intracranial stent placed in the anterior circulation. MATERIALS AND METHODS: Nine patients treated with stent-assisted coil embolization for anterior circulation aneurysms underwent MRAs (Silent MRA and TOF MRA) and x-ray digital subtraction angiography. MRAs were performed in the same session on a 3T unit. Two neuroradiologists independently reviewed the MRA images and subjectively scored flow in a stent as 1 (not visible) to 4 (excellent) by referring to the latest x-ray digital subtraction angiography image as a criterion standard. RESULTS: Both observers gave MRA higher scores than TOF MRA for flow in a stent in all cases. The mean score for Silent MRA was 3.44 ± 0.53, and for TOF MRA, it was 1.44 ± 0.46 (P < .001). CONCLUSIONS: Silent MRA was able to visualize flow in an intracranial stent more effectively than TOF MRA. Silent MRA might be useful for follow-up imaging after stent-assisted coil embolization, though these study results may be only preliminary due to some limitations.