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991.
992.

Background

To obtain information on affected vessels in moyamoya disease (MMD), we analyzed the vascular morphological characteristics of MMD using three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance imaging (MRI).

Methods

The population of this 3D-CISS MRI study consisted of 51 patients with MMD: 16 patients with atherosclerotic middle cerebral artery (MCA) stenosis or occlusion, 42 MRI control patients, and 28 control digital subtraction angiography (DSA) patients. We measured the outer diameters of the terminal portion of the internal carotid artery (ICA) and the proximal portion of the MCA (M1 portion). We evaluated the inner diameter as the relative value (%) obtained from magnified DSA images and analyzed these data.

Results

The outer diameters of the ICA and M1 portions were significantly smaller in the MMD group than in the other two groups, while the M1 outer diameter of the atherosclerosis group was not significantly different compared to the control (ICA: MMD, 2.61?±?0.46?mm vs. control, 4.04?±?0.50?mm and M1: MMD, 1.92?±?0.43?mm vs. control, 3.34?±?0.54?mm vs. atherosclerosis, 3.45?±?0.56?mm). Furthermore, in MMD patients, the outer diameter was unrelated to the progression of the luminal stenosis grade estimated by DSA.

Conclusions

This is the first report that the outer diameters of both the ICA and M1 decrease in MMD patients. Our findings suggest that the vascular constrictive changes of the affected arteries are an important phenomenon reflecting MMD pathology.  相似文献   
993.
We report a rare case of mediastinal desmoid tumor in a 17-year-old man. The patient was a 17-year old man who had underwent surgery for mediastinal tumor at our hospital 2 years before. The tumor was diagnosed as a solitary fibrous tumor of the mediastinum. After 2 years, chest computed tomography(CT) and magnetic resonance imaging( MRI) showed a mass at the previously resected site. Surgery was performed again under the diagnosis of recurrent tumor. The tumor densely adhered to the superior vena cava, right innominate vein, pericardium, and the right lung. The tumor was completely resected with the aid of the partial extracorporeal circulation. Finally, both previously resected tumor and the recurrent tumor were diagnosed pathologically as desmoid tumors.  相似文献   
994.
995.
996.
The effects of left ventricular assist system (LVAS) implantation on renal hemodynamics remains to be fully elucidated. We evaluated renal function and intrarenal blood flow in five advanced heart failure patients who had been supported with a Toyobo LVAS for bridge to heart transplantation. Renal function expressed as estimated glomerular filtration rate (eGFR) was calculated using the modified formula of Modification of Diet in Renal Disease. Mean blood velocities in the bilateral segmental arteries during systolic and diastolic perfusion were measured using duplex Doppler sonography, and renal vascular resistance (resistive index [RI]) of the segmental arteries was defined as (peak systolic velocity [PSV]-end-diastolic velocity [EDV])/PSV. All studies were performed before and after implantation (mean duration of support, 15.6±10.9 months). LVAS implantation significantly improved eGFR (42.7±7.9 to 64.1±16.3mL/min, P<0.05). Beat-by-beat measurements of heart rate did not change significantly. Mean PSV decreased significantly (38.2±8.9 to 28.3±2.2cm/s, P<0.05), and mean EDV increased significantly (8.3±3.2 to 11.3±1.3cm/s, P<0.05), and thus, mean RI was significantly improved (0.79±0.06 to 0.60±0.04, P<0.01). In conclusion, in advanced heart failure patients, pulsatile LVAS implantation is associated with improved renal function, and this improvement may be mediated in part through an improvement of intrarenal hemodynamics.  相似文献   
997.

Introduction

Patients aged 60?years and older represent the fastest-growing population with end-stage renal disease worldwide, and the need for a kidney transplant among this population is increasing. Due to the severe shortage of deceased donors in Japan, ABO-incompatible living donor kidney transplantation has been performed since the late 1980s. Excellent long-term outcomes have been achieved, and the rates of graft survival in these patients are currently similar to those in recipients of ABO-compatible grafts. However, the outcomes of ABO-incompatible kidney transplantation in elderly patients over 60?years of age have not been well studied yet.

Patients and methods

We studied 4 elderly kidney transplant patients who received their grafts from ABO-incompatible living donors at our institution between December 2006 and December 2011, focusing on the immunosuppressive protocols, complications and graft survivals. The mean observation period was 21.5?months (range, 8?months to 62?months). Our immunosuppressive protocols were as follows: to remove the anti-A/B antibodies, the patients underwent 4?C8 sessions of double-filtration plasmapheresis and/or plasma exchange prior to kidney transplantation until the anti-A/B titers were less than 1:16. For the patients with low anti-A/B titers (<1:512), the immunosuppressive protocol consisted of a single dose of rituximab (150?mg/m2). The patients with high anti-A/B antibody titers (??1:512) underwent splenectomy and received 2 doses of rituximab. The pretransplant immunosuppressive protocol included B-lymphocyte suppression with 4?weeks of mycophenolate mofetil (0.5?g/day for low-titer protocol and 1?g/day for high-titer protocol).

Results

All 4 patients underwent successful transplantation. At the end of follow-up, their mean serum creatinine was 1.18?mg/dl. No patient experienced antibody-mediated rejection or acute cellular rejection. Late-onset neutropenia occurred in two cases. Two cases experienced cytomegalovirus reactivation by cytomegalovirus antigenemia. In one patient, diffuse hemorrhage required surgical intervention. However, there were no severe complications.

Conclusions

Although a careful evaluation of patients is needed, ABO-incompatible kidney transplantation may become a viable treatment option for elderly patients with end-stage renal disease.  相似文献   
998.
Relapsing polychondritis (RP) is a rare, generalized autoimmune disorder that is characterized by recurrent inflammation of various cartilaginous structures. Involvement of the central nervous system is rarely observed in RP. Here we report a case of encephalitis associated with RP. A 60-year-old man presented with headache and bilateral ear swelling. Three weeks later, he came to our hospital because of the acute onset of a speech impediment. A non-contrast computed tomography scan of the head showed slight high-density areas in his left frontal lobe, but he refused to be admitted and went home. On the next day, he developed acalculia, agraphia, right-left disorientation, and mild right hemiparesis. Brain MRI revealed hyperintensity areas in the left frontal sulcus on fluid-attenuated inversion recovery (FLAIR) images, and these hyperintensity areas were enhanced by gadolinium. Therefore, the patient's symptoms were diagnosed as focal epilepsy caused by meningoencephalitis. Other examinations, including laboratory blood tests, cerebrospinal fluid tests, and a cerebral angiography, were all negative. Therefore, a brain biopsy of the left frontal cortex was performed 5 days after the patient's admission. Pathological findings revealed chronic inflammation of the meninges, so prednisone was administered. After receiving oral prednisone, the patient's bilateral ear swelling dramatically improved and the lesions apparent on cranial MRI gradually subsided. The patient was diagnosed with RP by a neurologist after discharge from the hospital. In this study, early diagnosis and steroid treatment is recommended for patients with neurological complications due to RP.  相似文献   
999.
We sought to clarify the controversial issue of whether detecting low‐level anti‐donor‐specific HLA antibody (HLA‐DSA) by single‐antigen flow‐bead assay (SAFB) may have a potential role in reducing acute and chronic antibody‐mediated rejection (AMR). We retrospectively studied the preoperative serum of ABO‐compatible living kidney transplantation recipients transplanted between 2001 and 2004 by SAFB using a Luminex platform. HLA‐DSA was detected only by SAFB in 24 patients, although all of them showed negative T‐cell and B‐cell complement‐dependent cytotoxicity (CDC) crossmatches. The HLA‐DSA patients went on to have surprisingly high levels of acute and chronic AMR despite being only weakly sensitized (acute AMR, 33.3%; chronic AMR, 41.7%). After 2005, we implemented SAFB routinely and any patient having a positive HLA‐DSA was considered to be a desensitization candidate. The 52 patients found to have HLA‐DSA underwent kidney transplantation after prior treatment with a single dose of rituximab (RIT) and three or four sessions of double‐filtration plasmapheresis (DFPP) in addition to regimens commonly used between 2001 and 2004. After 2005, there was a significant reduction in the occurrence of acute and chronic AMR (acute AMR, 4.7%, P < 0.001; chronic AMR, 4.7%, P < 0.001). The 5‐year graft survival rate also improved after implementing SAFB (83.3–98.1%, P = 0.032). The RIT/DFPP‐induction protocol may improve graft survival even in patients with low‐level DSA.  相似文献   
1000.
Interstitial, angular, and cornual pregnancies and intrauterine pregnancies in an anomalous uterus are separate entities, and the impact of each condition on obstetric outcomes is completely different. However, there is considerable confusion in understanding and managing the natural course of each condition due to a lack of uniform terminology. The single most important factor for differentiating these types of pregnancies is to make an early diagnosis. The differences between interstitial, angular, and cornual pregnancies on 2‐dimensional (2D) sonography are subtle. Although magnetic resonance imaging can be used to differentiate these conditions, it is not preferred as the initial assessment tool because of its limited availability and cost‐effectiveness. Three‐dimensional (3D) sonography has the advantage of providing views of the uterus that cannot be obtained with conventional 2D sonography. We describe 3 cases of interstitial, angular, and intrauterine pregnancies in a septate uterus that were clearly differentiated by 3D sonography. We demonstrate the differences in diagnostic imaging findings and emphasize the importance of 3D sonography in differentiating these entities.  相似文献   
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