Dual-Energy CT of Material Decomposition Analysis for Detection with Bone Marrow Edema in Patients with Vertebral Compression Fractures.

RATIONALE AND OBJECTIVES: This study investigated detecting bone marrow edema (BME) in patients with vertebral compression fractures. We compared dual-energy material density analysis images to magnetic resonance imaging (MRI), which is considered the gold standard. MATERIALS AND METHODS: In this retrospective study, 260 vertebral bodies from 30 patients (11 males, 19 females, mean age of 81) were assessed by MRI and dual-energy material density analysis. Diagnostic accuracy was assessed using the receiver operating characteristic (ROC) curve. Fifty-two of the 260 vertebral bodies were considered to have BME based on the dual-energy material density analysis images; 50 were deemed to have BME by MRI. RESULTS: ROC analysis of the dual-energy material density analysis values revealed an area under the ROC curve of 0.95 for radiologist 1, 0.97 for radiologist 2, and 0.96 for radiologist 3. A mean cutoff value of 1032.6 mg/cm3 provided an overall sensitivity of 93.0% (95% confidence intervals [CI]: 86.0%-99.9%), specificity of 98.0% (95% CI: 95.5%-99.0%), accuracy of 97.0% (95% CI: 95.2%-99.0%), positive predictive value of 95.0% (95% CI: 81.0%-97.5%), and negative predictive value of 98.0% (95% CI: 93.0%-99.9%). CONCLUSION: BME in patients with vertebral compression fractures can be detected using dual-energy material density analysis images.

SPECT/CT Fusion in the Diagnosis of Hyperparathyroidism.

OBJECTIVES: In this study, we aimed to analyze the relationship between the diagnostic ability of fused single photon emission computed tomography/ computed tomography (SPECT/CT) images in localization of parathyroid lesions and the size of adenomas or hyperplastic glands. METHODS: Five patients with primary hyperparathyroidism (PHPT) and 4 patients with secondary hyperparathyroidism (SHPT) were imaged 15 and 120 minutes after the intravenous injection of technetium99m-methoxyisobutylisonitrile ((99m)Tc-MIBI). All patients underwent surgery and 5 parathyroid adenomas and 10 hyperplastic glands were detected. Pathologic findings were correlated with imaging results. RESULTS: The SPECT/CT fusion images were able to detect all parathyroid adenomas even with the greatest axial diameter of 0.6 cm. Planar scintigraphy and SPECT imaging could not detect parathyroid adenomas with an axial diameter of 1.0 to 1.2 cm. Four out of 10 (40%) hyperplastic parathyroid glands were diagnosed, using planar and SPECT imaging and 5 out of 10 (50%) hyperplastic parathyroid glands were localized, using SPECT/CT fusion images. CONCLUSION: SPECT/CT fusion imaging is a more useful tool for localization of parathyroid lesions, particularly parathyroid adenomas, in comparison with planar and or SPECT imaging.

An unusual unilocular mesothelial cyst of the pleura: a case report.

A 79-year-old woman was found to have an abnormal shadow on chest radiography. Computed tomography demonstrated a pleural mass. The F-18 fluorodeoxyglucose positron emission tomography (FDG PET) was performed to determine whether the pleural mass was benign or malignant. The histologic examination of the resected mass showed a unilocular mesothelial cyst of the pleura. The FDG PET findings of a mesothelial cyst of the pleura have not yet been previously reported. The FDG PET findings of a mesothelial cyst in the pleura reflected the microscopic findings of the resected mass. The FDG PET findings, therefore, seem to be useful in the diagnosis of mesothelial cysts.

Computed tomography-based three-dimensional dosimetry of intracavitary brachytherapy for cervical cancer.

PURPOSE: The aim of this study was to show the results of computed tomography (CT)-based dosimetry of intracavitary brachytherapy for cervical cancer. MATERIALS AND METHODS: A total of 20 patients with cervical cancer underwent intracavitary brachytherapy with external beam radiation therapy. The prescribed dose of brachytherapy was 6 Gy per fraction to point A. In every fraction a CT scan was performed after applicator insertion and three-dimensional (3D) dosimetry was done. The tumor dose was evaluated using D90 (the minimum dose delivered to 90% of the volume), and the doses of risk organs were evaluated using D2cc (the minimum dose in the most irradiated 2 cm3 of the volume). RESULTS: The mean D90 for the clinical target volume (CTV) was 7.0 Gy (range 4.8-9.8 Gy). There was a negative correlation between the volume and the D90 for the CTV. The mean D2cc doses for the rectum and bladder were 6.0 Gy (range 3.9-9.0 Gy) and 6.5 Gy 5 Gy 2.9-9.0 Gy), respectively. CONCLUSION: CT-based 3D dosimetry of intracavitary brachytherapy for cervical cancer was useful for evaluating the doses of the CTV and the organs at risk. In cases with a large CTV, CTV D90 was often lower than the point A dose, and modulation of the prescribed dose might have to be considered.

Reactivation of hepatitis and lamivudine therapy in 11 HBsAg-positive renal allograft recipients: a single centre experience.

BACKGROUND: In hepatitis B virus (HBV) surface antigen (HBsAg) (+) renal allograft recipients, the mortality associated with liver disease reaches 37-78%. An antiviral agent, lamivudine, has recently been reported to be safe and effective for preventing hepatic damage in these patients, although either resurgence of HBV-DNA levels after discontinuation or emerging resistant HBV mutants caused by long-term administration are still unsettled. METHODS: Between July 1976 and December 2003, 555 renal transplantations were performed in our centre. Of these, 11 patients who were HBsAg (+) at the time of transplantation (2.0%) were selected for this study. We investigated the incidence of hepatitis reactivation for three yr after transplantation and their clinical courses, including the efficacy of lamivudine therapy in seven of the 11 patients. RESULTS: Six episodes of hepatitis reactivation developed in five of the 11 patients (45.5%) within three yr after transplantation. Five episodes of six occurred within four months after transplantation. The patient who underwent the most severe reactivation needed intensive care including lamivudine administration and plasma exchange. Lamivudine caused no severe adverse effects and HBV-DNA levels dropped to under measurable levels within four months after lamivudine administration in all patients. Resistant HBV mutant emerged in only one patient, who had the longest lamivudine administration of 49 months. CONCLUSIONS: For HBsAg (+) renal allograft recipients, careful monitoring of HBV-DNA levels and timely administration of lamivudine could prevent hepatic damage caused by reactivation of hepatitis.

Differentiation between hepatic cyst and hemangioma: additive value of breath-hold, multisection fluid-attenuated inversion-recovery magnetic resonance imaging using half-Fourier acquisition single-shot turbo-spin-echo sequence.

PURPOSE: To evaluate the additive value of breath-hold, multisection fluid-attenuated inversion-recovery (FLAIR) magnetic resonance imaging (MRI) using half-Fourier acquisition single-shot turbo-spin-echo (HASTE) sequence as supplements to moderately and heavily T2-weighted fast-spin-echo (FSE) sequences in differentiating hepatic cyst from hemangioma. MATERIALS AND METHODS: A total of 183 lesions (127 hepatic cysts, 56 hepatic hemangiomas) in 117 patients were evaluated in this study. Three radiologists independently reviewed FLAIR MR images using a HASTE sequence and T2-weighted FSE MR images. Each radiologist used a five-point scale to rate his confidence in determination of hepatic cyst and hemangioma. RESULTS: All three reviewers were significantly better able to differentiate hepatic cyst from hepatic hemangioma with the combination of FLAIR imaging using HASTE and moderately and heavily T2-weighted FSE images (area under the receiver operating characteristic (ROC) curve, 0.99 for each reader) than with moderately and heavily T2-weighted FSE images alone (0.82-0.93; P < 0.05). FLAIR-HASTE imaging in addition to T2-weighted FSE sequences improved the diagnostic performance, including the sensitivity, specificity, accuracy, and confident diagnosis in the differentiation between hepatic hemangiomas and cysts. CONCLUSION: FLAIR-HASTE imaging is useful for distinguishing hepatic hemangioma from hepatic cyst without the use of contrast-enhanced MR images.

Severe elevations of FK506 blood concentration due to diarrhea in renal transplant recipients.

BACKGROUND: The rate of metabolism in the intestine of oral administered FK506 decreases as FK506 passes on to the lower intestine. In transplant recipients with diarrhea given oral FK506, the main areas for absorption of FK506 shift to the lower intestine, where the ability to metabolize FK506 is weaker. Therefore it is considered likely that when FK506 is administered to recipients with diarrhea, the blood concentration of FK506 will be higher. MATERIAL AND METHODS: Twenty recipients experiencing episodes of diarrhea were investigated to determine the trough level of FK506 and the time required for the FK506 trough level to return to the level that obtained before diarrhea. AUC0-4h and Cmax of FK506 were investigated in eight recipients. In cases with severe diarrhea, the daily fluctuations of FK506 blood concentration were also investigated. RESULT: The FK506 trough level (p < 0.0001), AUC (p = 0.0173), and Cmax (p = 0.0173) were found to be significantly higher during episodes of diarrhea. In almost all cases, it took between 2 and 4 wk for the elevated FK506 trough level to return to its previous level following a bout of diarrhea. In the daily fluctuations of FK506 concentration, Tmax was prolonged. In some cases, the concentration was highest just before administration of FK506, when it should have been at trough level. CONCLUSIONS: Diarrhea caused significant elevations of trough level, AUC0-4h and Cmax of FK506, and the prolongation of Tmax in renal transplant recipients administered FK506.

Use of PCR and PCR-SSP for detection of urinary donor-origin DNA in renal transplant recipients with acute rejection.

OBJECTIVE: To analyze the urine of renal recipients for the presence of donor DNA in an attempt to establish an alternative diagnostic means of acute rejection. METHODS: Sixty-four renal transplant recipients were examined. Thirty-seven were normal after transplantation, while 22 others developed acute rejection, based on serum creatinine levels and/or needle biopsy findings of the graft. Five developed drug-induced renal dysfunction. In female recipients with a male graft, we examined urine for the presence of Y chromosome (SRY and DYZ-1) and in recipients receiving an HLA mismatched graft, we looked for HLA-DR gene (DRB1) using PCR. RESULTS: Among the 14 female recipients with male grafts demonstrating stable renal function, only one was positive for SRY and DYZ-1 on the Y chromosome. However, SRY and DYZ-1 were found in the urine of four female patients with acute rejection, but these DNA fragments were not detected in 3 of the 4 after anti-rejection therapy. The last patient was referred to hemodialysis. Of 23 recipients of a graft from HLA mismatch donors with stable renal function, DRB1 was negative in 21 (91%). Of 18 patients with acute rejection, DRB1 was positive in 16 (89%) and negative in 2. These DNA fragments were no longer found in 13 patients after anti-rejection therapy. In all patients with drug induced renal dysfunction, donor-derived DNA was negative. CONCLUSIONS: Presence of door specific DNA in the urine of the recipient is strongly associated with acute rejection. Analysis of DNA derived from donor cells in urine was an effective and accurate method for the diagnosis of acute rejection of a renal transplant.

Prophylactic deoxyspergualin treatment in living-related renal-transplant recipients transfused with donor-specific blood.

BACKGROUND: Deoxyspergualin (DSG) prophylaxis has improved long-term graft survival in living-related renal-transplant recipients transfused with donor-specific blood (DST). We examined the influence of acute rejection (AR) on graft survival in these patients. METHODS: The study groups consisted of either historic control recipients without DSG (group A, n=64, 1985-1989) and recipients with DSG as the initial immunosuppressive agent (group B, n=76, 1989-1995). Both groups received DST from a one-haplotype identical donor and were treated with cyclosporine-based immunosuppression. Rejection was classified into accelerated rejection (Acc, within 5 days), AR (from 6 days-3 months), and late AR (LAR, from 4 months-1 year). RESULTS: Overall 5-year graft survival rates were significantly higher in group B than group A (89.5 vs. 73.4%, P=0.0070). Each group was then subdivided on the basis of whether or not they had an episode of Acc, AR, or LAR. In group A, 5-year graft survival rate was not affected the presence or absence of Acc (75.0 vs. 73.1%), and it was influenced significantly by the presence or absence of AR (50.0 vs. 85.7%, P=0.0012) or LAR (46.7 vs. 81.6%, P<0.0001). In group B, 5-year graft survival did not change significantly by the presence or absence of Acc (100 vs. 88.7%), AR (81.8 vs. 92.6%), or LAR (81.0 vs. 92.7%). CONCLUSIONS: Prophylactic use of DSG in living-related renal-transplant recipients treated with DST improves long-term graft survival, even in patients with AR episodes.

Analysis of urinary donor-derived DNA in renal transplant recipients with acute rejection.

In renal transplantation we usually diagnose an acute rejection by based on the results of a needle biopsy; however, this takes time and findings in some cases are not definite. We analysed the urine of renal recipients for the presence of donor DNA in an attempt to establish a diagnostic means of acute rejection. Sixty-four renal transplant recipients were examined. Thirty-seven patients had no trouble after transplantation and 22 patients developed acute rejection, diagnosed based on serum creatinine levels and/or needle biopsy findings of the graft. Five patients had drug-induced renal dysfunction. In female recipients with a male graft we examined urine for the presence of Y-chromosome (SRY and DYZ-1) and in recipients receiving a HLA mismatched graft we investigated the HLA-DR gene (DRB1) by the polymerase chain reaction (PCR) method. Among female recipients with a male graft there were 14 patients with stable renal function and SRY and DYZ-1 on Y-chromosome were negative in 13 (93%) and positive in one, whereas SRY and DYZ-1 of urine were positive in the four female patients with acute rejection and these DNA fragments disappeared in three after rejection therapy. One patient was subjected to haemodialysis. Among 23 recipients of a graft from HLA mismatched donors with stable renal function, DRB1 was negative in 21(91%). Among 18 patients with acute rejection DRB1 was positive in 16 (93%) and negative in two. These DNA fragments disappeared in 13 patients after rejection therapy. In all patients with drug-induced renal dysfunction donor-derived DNA was negative. Presence of donor-specific DNA in the urine of the recipient is associated strongly with acute rejection and analysis of DNA derived from donor cells in urine might be an effective and accurate method for the diagnosis of acute rejection of a renal transplant.