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991.
Pigmented villonodular synovitis of the temporomandibular joint: MR findings in four cases 总被引:1,自引:0,他引:1
Kim KW Han MH Park SW Kim SH Lee HJ Jae HJ Kang JW Chang KH 《European journal of radiology》2004,49(3):229-234
OBJECTIVE: Although it is a rare condition, pigmented villonodular synovitis (PVNS) may involve temporomandibular joint (TMJ). The purpose of this study was to describe magnetic resonance (MR) findings of PVNS of the TMJ. METHODS AND MATERIAL: Between April 1992 and August 2000, four patients (two men and two women, 22-58-year-old) who had histologically proven diagnoses of PVNS in their TMJ were found in our institution. Their MR findings were reviewed retrospectively, and were correlated with pathologic findings. RESULTS: In all four patients, MR images invariably showed profound hypointensity on both T1- and T2-weighted sequences. This finding was seen diffusely and homogeneously throughout the lesion, and was considered to be due to paramagnetic effect attributed to heavy hemosiderin pigmentation, which was revealed by histopathological examination. MR images also showed aggressive nature of the lesions with adjacent skull base destruction and intracranial extension in two of them. CONCLUSION: As is the case in the other anatomic site, PVNS of the TMJ can be confidently diagnosed on MR imaging on the basis of the presence of hemosiderin. MR imaging also plays a pivotal role in surgical planning by precise and detailed localization of the lesion. 相似文献
992.
Won JH Kim BM Kim CH Park SW Kim MD 《Journal of vascular and interventional radiology : JVIR》2004,15(6):595-600
PURPOSE: To evaluate the efficacy of percutaneous image-guided sclerotherapy of lymphangiomas with use of acetic acid. MATERIALS AND METHODS: Twelve patients with lymphangiomas were treated with acetic acid as the sclerosant. There were eight male patients and four female patients, ranging in age from 1 to 29 years (mean, 11 years). The lymphangiomas were located at the neck (n = 5), upper extremity (n = 3), axilla (n = 1), cervicomediastinum (n = 1), anterior chest wall (n = 1), and retroperitoneum (n = 1). Two patients had recurrent lymphangiomas after surgery and two patients had undergone failed sclerotherapy with another sclerosant. The acetic acid used as the sclerosant was 40%-50% in concentration, and the amounts used ranged from 2 mL to 70 mL (mean, 11.3 mL), which was equivalent to 4.6%-50% (mean, 30.6%) of the aspirated lymphatics. All procedures were performed under ultrasonographic and fluoroscopic guidance. The sclerosant was removed after sclerotherapy. All patients except one underwent one treatment session. RESULTS: Complete resolution of the lymphangioma was achieved in eight patients (66.7%), good resolution (>50% reduction) was achieved in three (25.0%), and poor resolution (<50% reduction) was seen in one (8.3%). Complications encountered included pneumonitis adjacent to the lymphangioma (n = 1), pain (n = 2), hematuria (n = 1), and tingling sensation in the forearm (n = 1). CONCLUSION: Percutaneous sclerotherapy of the lymphangiomas with use of acetic acid is an effective method without serious complications. 相似文献
993.
PURPOSE: Increasing clinical importance is being placed on the role of differential renal function (DRF) in the management of congenital ureteropelvic junction obstruction. Supranormal DRF of the hydronephrotic kidney on renal scan is a puzzling phenomenon and is hypothesized to be due to an increase in single nephron filtration or nephron volume without sound evidence. We studied the histopathological changes of hydronephrotic kidneys to determine whether glomerular hypertrophy underlies supranormal DRF. MATERIALS AND METHODS: We retrospectively evaluated the records of 3 females and 32 males with unilateral congenital hydronephrosis who underwent pyeloplasty. Mean patient age at operation was 12.6 months (range 0.1 to 144). Needle biopsies from 3 different sites at the lower pole of the kidney were performed during surgery. To evaluate the presence of glomerular hypertrophy, the maximal planar area of glomeruli was measured under light microscopy using an image analyzer. Tissue samples obtained from kidneys without a history of urinary tract disease at autopsy were used as controls. The mean glomerular areas of the patient and control groups were evaluated according to DRF and age. RESULTS: The mean glomerular area values of the patient group were smaller than those of the control group, except for 4 patients. The glomerular areas of the hydronephrotic kidneys with supranormal DRF were not significantly different from those of the control group. Instead, the probability of larger renal glomeruli increased with decreasing DRF (p = 0.1155). CONCLUSIONS: Increased nephron volume can be discounted as a cause of supranormal DRF. 相似文献
994.
We report a diabetic renal transplant recipient who experienced an episode of acute allograft rejection in the 6th month posttransplant when there was an attempt at steroid withdrawal. The acute rejection was steroid resistant. Furthermore calcineurin inhibitor nephrotoxicity was exacerbated by rescue therapy with tacrolimus conversion. The allograft dysfunction ultimately stabilized upon institution of sirolimus and minimization of tacrolimus. 相似文献
995.
The aim of this study was to evaluate the role of osteopontin (OPN) in cyclosporine (CsA) nephrotoxicity of the human kidney. Renal biopsy samples obtained before and after 1–2 years of CsA treatment were evaluated in 18 children (2.2–13.0 years, 14 males, 4 females) diagnosed with minimal change nephrotic syndrome. The changes in tubular OPN expression between pre- and post-treatment samples were correlated with interstitial macrophage infiltration, transforming growth factor- (TGF-) expression, interstitial fibrosis, and microvascular density. OPN, TGF-, CD68, and CD34 positivity were quantitatively assessed by immunohistochemical staining. Light microscopy showed that interstitial fibrosis developed in two-thirds of patients after CsA treatment. However, CD68-positive macrophages infiltrated minimally in fibrotic areas and were found in only one-third of patients. OPN expression was significantly increased in the glomerular mesangium (P=0.001) and tubules (P=0.025) after CsA treatment, whereas the number of CD34-positive peritubular capillaries decreased (P=0.022). An inverse relationship was observed between tubular OPN expression and microvascular density (r=–0.644). However, tubular OPN expression was not related to proteinuria, interstitial fibrosis, or interstitial or tubular TGF- expression. This study indicates that increased OPN expression may be related to microvascular injury in human CsA nephrotoxicity. It also shows that OPN expression may be used as an early but non-specific marker of CsA toxicity before the manifestation of interstitial fibrosis. 相似文献
996.
Yang KH Yoon CS Park HW Won JH Park SJ 《Archives of orthopaedic and trauma surgery》2004,124(3):169-172
Introduction Adduction of the ipsilateral hip joint is necessary to facilitate closed hip nailing for trochanteric fracture. Even though positioning the patient supine with the perineal post against the ipsilateral medial thigh can change the course of the neurovascular structure in the proximal thigh, there have been no reports regarding the position of the femoral artery in the hip nailing position.Materials and methods We studied the position of the superficial femoral artery in 59 thighs using color-flow duplex scanning method in three hip nailing positions.Results The mean of the distance between the superficial femoral artery and the femur in 48 normal limbs was 20.28 mm in neutral position (D1), 11.85 mm in 20o adduction (D2), and 9.53 mm in 20o adduction plus 20o internal rotation of the foot plate (D3). The distances D2 and D3 were always shorter than D1 (p<0.001). D3 was less than 10 mm in 30 of the normal limbs (62.5%) and less than 5 mm in 4 (8%). In 11 patients who sustained a trochanteric fracture, the mean of D1, D2, and D3 in the injured limbs was 25.28 mm, 17.98 mm, and 14.38 mm, respectively. The mid-thigh circumference and D3 of the injured limbs were always greater than those of the normal limbs (p<0.001). However, D3 of both sides was less than 10 mm in 3 patients.Conclusion To lessen the vascular injury during hip nailing, we recommend that the limb be placed in neutral position during preparation of the interlocking holes. 相似文献
997.
Delayed hemorrhage after pancreaticoduodenectomy 总被引:11,自引:0,他引:11
Choi SH Moon HJ Heo JS Joh JW Kim YI 《Journal of the American College of Surgeons》2004,199(2):186-191
BACKGROUND: Postoperative hemorrhage, particularly delayed hemorrhage after pancreaticoduodenectomy, is a serious complication and one of the most common causes of mortality after pancreaticoduodenectomy. STUDY DESIGN: The medical records of 500 patients who underwent pancreaticoduodenectomy between October 1994 and December 2002 were analyzed with regard to postoperative hemorrhagic complications. Delayed hemorrhage was defined as bleeding at the operation site after 5 or more postoperative days. RESULTS: Delayed hemorrhage occurred in 22 patients (4.4%), with a median time of 13 days (range 7 to 32 days) after pancreaticoduodenectomy, and developed more frequently (9/77 versus 13/423, p = 0.003) in patients with preceding intraabdominal complications such as pancreatic fistula, bile fistula, and intraabdominal abscess. In 17 of these 22 patients, angiography and laparotomy revealed bleeding foci at 14 arterial and 3 anastomotic sites. In nine patients, hemorrhage developed from pseudoaneurysms of the major arteries around the pancreaticojejunostomy. Hemostatis was attempted by transcatheter arterial embolization in 14 patients and with laparotomy in 4 patients. Four of 14 patients who received transcatheter arterial embolization eventually required laparotomy. Overall, 4 of the 22 delayed hemorrhage patients died (18.2%) of complications related to massive bleeding or transcatheter arterial embolization. CONCLUSIONS: Delayed hemorrhage after pancreaticoduodenectomy is associated with a high mortality. Intraabdominal complications after pancreaticoduodenectomy should be evaluated properly and guidelines for the diagnosis and treatment of delayed hemorrhage should be established in advance. Clinicians must be alert to the possibility of pseudoaneurysm hemorrhage. 相似文献
998.
Relationship of plasma Dendroaspis natriuretic peptide-like immunoreactivity and echocardiographic parameters in chronic haemodialysis patients 总被引:1,自引:0,他引:1
BACKGROUND AND AIMS: The Dendroaspis natriuretic peptide (DNP), which was recently isolated from the venom of the green Mamba snake, Dendroaspis angusticeps, is a 38 amino acid peptide containing a 17 amino acid disulfide ring structure. The purpose of this study was to evaluate the effect of haemodialysis (HD) on the plasma concentration of DNP, and to investigate the relationship between the 2-D echocardiographic parameters and the changes in the plasma DNP levels during HD. METHODS: Forty-five haemodialysis patients and 22 healthy individuals underwent a measurement of plasma DNP-like immunoreactivity, serum creatinine, haematocrit, blood pressure and bodyweight before and after each HD session. Echocardiography was performed before and after HD. The peak early diastolic transmitral flow velocity (E), peak late diastolic transmitral flow velocity (A), and E/A ratio were measured by using a pulsed Doppler echocardiogram. RESULTS: The plasma DNP-like immunoreactivity of those in the pre-HD state was significantly higher (235.6 +/- 45.8 pg/mL) than those of the healthy subjects (105.3 +/- 31.1 pg/mL). In addition, the plasma DNP-like immunoreactivity was significantly decreased after HD (204.4 +/- 55.4 pg/mL). The left atrial diameter, left ventricular diameter at end diastole and end systol, E velocity, A velocity, E/A ratio and inferior vena cava diameter were significantly decreased after HD. There were significant correlations between the changes of plasma DNP-like immunoreactivity and the changes in the bodyweight and inferior vena cava diameter, respectively. CONCLUSION: These results suggest that the plasma DNP-like immunoreactivity might be involved in the regulation of the blood volume in patients undergoing HD. 相似文献
999.
Persistent pulmonary hypertension of the newborn infant (PPHN), is a clinical syndrome characterized by elevated pulmonary vascular resistance, resulting from reactive vasoconstriction or structural remodeling of the pulmonary vasculature. Although inhaled nitric oxide (iNO) has emerged as a novel selective treatment of PPHN, responses to iNO are variable according to the etiologies or the clinical situation. A retrospective chart review of 51 newborn infants with PPHN and treated with iNO, was undertaken to evaluate the factors affecting response to iNO. Response to iNO was defined as a reduction in the oxygenation index (OI) of more than 20%, or disappearance of the difference in oxygen saturation between preductal and postductal circulation after iNO therapy. The patients were divided into two groups; the responder group and the non- responder group. Respiratory distress syndrome (RDS) was more commonly associated with PPHN in the responder group than in the non-responder group (p < 0.05), while there were many more patients with congenital diaphragmatic hernia (CDH) in the non-responder group than in the responder group (p < 0.05). Infants with meconium aspiration syndrome (MAS) were similar in both of the two groups. Initial OI, initial mean airway pressure (MAP), and initial and peak NO concentration were significantly lower in the responder group compared to the non-responder group (p < 0.05). Rapid response (response to iNO within the first hour) was shown in 74% of the responder group and 33% of the nonresponder group (p < 0.05). There was no significant differences in the initial chest radiographic findings, such as normal, focal or bilateral diffuse infiltration, with the exception of CDH, between each group. Lower initial OI, lower initial MAP and significant response within the first hour were shown to be favourable factors in response to iNO therapy. Patients with RDS associated with PPHN responded much better to iNO than those with other diseases. 相似文献
1000.
Altered expression of KCNK9 in colorectal cancers 总被引:3,自引:0,他引:3
Kim CJ Cho YG Jeong SW Kim YS Kim SY Nam SW Lee SH Yoo NJ Lee JY Park WS 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(9):588-594
K(+) channels have been reported to be involved in the proliferation of many types of cells, including some human carcinoma and tumor cell lines. KCNK9, a TASK channel, is amplified and overexpressed in several types of human cancer. In the present study, we examined the expression and somatic mutations of KCNK9 in 124 colorectal cancers by immunohistochemistry using tissue microarray and PCR-SSCP. Immunopositivity was observed in 57 (46.0%) of 124 colorectal cancers. Clinically, KCNK9 was immunopositive in 4 (30.7%) of 13 cases which were stage A, 26 (55.3%) of 47 which were stage B, 23 (41.1%) of 56 which were stage C, and 4 (50%) of 8 which were stage D. Statistically, KCNK9 protein expression was not related to tumor stage (Bartholomew test, p>0.05) and lymph node metastasis (Chi-Square test, p=0.8338). In the mutation study of the KCNK9 gene, we found only one sequence variation (ACG-->ACC, Thr-->Thr) at codon 170 both in corresponding normal and tumor DNAs. These results indicate that overexpression rather than mutation of the KCNK9 gene may contribute to the development of colorectal cancers and suggest that the development of KCNK9-targeted agents may provide new possibilities in the treatment of colorectal cancer. 相似文献