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991.
992.

Background

To diagnose sputum smear-negative pulmonary tuberculosis (PTB) is difficult and the ability of high-resolution computed tomography (HRCT) for diagnosing PTB has remained unclear in the sputum smear-negative setting. We retrospectively investigated whether or not this imaging modality can predict risk for sputum smear-negative PTB.

Methods

We used HRCT to examine the findings of 116 patients with suspected PTB despite negative sputum smears for acid-fast bacilli (AFB). We investigated their clinical features and HRCT-findings to predict the risk for PTB by multivariate analysis and a combination of HRCT findings by stepwise regression analysis. We then designed provisional HRCT diagnostic criteria based on these results to rank the risk of PTB and blinded observers assessed the validity and reliability of these criteria.

Results

A positive tuberculin skin test alone among clinical laboratory findings was significantly associated with an increase of risk of PTB. Multivariate regression analysis showed that large nodules, tree-in-bud appearance, lobular consolidation and the main lesion being located in S1, S2, and S6 were significantly associated with an increased risk of PTB. Stepwise regression analysis showed that coexistence of the above 4 factors was most significantly associated with an increase in the risk for PTB. Ranking of the results using our HRCT diagnostic criteria by blinded observers revealed good utility and agreement for predicting PTB risk.

Conclusions

Even in the sputum smear-negative setting, HRCT can predict the risk of PTB with good reproducibility and can select patients having a high probability of PTB.  相似文献   
993.
Patients with mild cognitive impairment (MCI) represent a risk population for progressing to dementia of the Alzheimer type (DAT). However, clinical criteria do not ensure reliable individual prognosis in these patients. The objective of this longitudinal, prospective study was to examine the value of (18)F-FDG PET of cerebral glucose metabolism and of genetic susceptibility, as defined by an APOEepsilon4-positive genotype, with regard to the early diagnosis of DAT in patients with MCI. METHODS: In 30 patients with the diagnosis of MCI (16 female, 14 male; age, 70 +/- 8 y), baseline and follow-up examinations (mean observation period, 16 mo) were performed. In all patients, the APOE genotype was assessed and cerebral glucose metabolism was evaluated at baseline using cranial (18)F-FDG PET. Individual PET data were screened for findings suggestive of Alzheimer's disease (AD), with the help of an automated computer program. After stereotactical normalization of the PET images, this program performs an observer-independent statistical comparison with an age-matched reference database (n = 22). RESULTS: In 43% of all MCI subjects, a PET scan suggestive of AD pathology according to our predefined criteria was observed at baseline (PET+); 57% of all MCI patients were carriers of the APOE epsilon4 allele (e4+). In 40% of all patients, progression of symptoms within the observation period justified the clinical diagnosis of probable DAT at the time of follow-up reevaluation. Statistical evaluation revealed the best results for PET with regard to early diagnosis of DAT in MCI patients (sensitivity, 92%; specificity, 89%). Classification according to the APOE genotype was significantly less successful (sensitivity, 75%; specificity, 56%). However, a combination of both diagnostic tests allowed early diagnosis with either very high specificity (PET+ AND e4+: sensitivity, 67%; specificity, 100%) or very high sensitivity (PET+ OR e4+: sensitivity, 100%; specificity, 44%). CONCLUSION: (18)F-FDG PET of cerebral glucose metabolism is a valuable diagnostic tool for the prediction of clinical outcome in individual MCI patients. Results are superior to the exclusive assessment of the APOE genotype. A combination of both functional imaging and genotyping may allow an early high-risk or low-risk stratification of patients with either very high sensitivity or very high specificity. This may be valuable, for example, for patient selection in scientific studies.  相似文献   
994.
Laryngeal and hypopharyngeal cancer, in particular T4a disease associated with cartilage invasion and extralaryngeal spread, needs to be evaluated accurately because treatment can impact heavily on a patient's quality of life. Reliable imaging tools are therefore indispensible. CT offers high spatial and temporal resolution and remains the preferred imaging modality. Although cartilage invasion can be diagnosed with acceptable accuracy by applying defined criteria for combinations of erosion, lysis and transmural extralaryngeal spread, iodine-enhanced tumors and non-ossified cartilage are sometimes difficult to distinguish. MR offers high contrast resolution for images without motion artifacts, although inflammatory changes in cartilage sometimes resemble cartilage invasion. With dual-energy CT, combined iodine overlay images and weighted average images can be used for evaluation of cartilage invasion, since iodine enhancement is evident in tumor tissue but not in cartilage. Extralaryngeal spread can be evaluated from CT, MR or dual-energy CT images and the routes of tumor spread into the extralaryngeal soft tissue must be considered; (1) via the thyrohyoid membrane along the superior laryngeal neurovascular bundle, (2) via the inferior pharyngeal constrictor muscle, and (3) via the cricothyroid membrane. Radiologists need to understand the advantages and limitations of each imaging modality for staging of laryngeal and hypopharyngeal cancer.  相似文献   
995.
AIM: To evaluate the image quality of MR angiography (MRA) with a peripheral vascular coil. MATERIALS AND METHODS: A peripheral vascular coil, a technical coil used in MRA of the pelvis and lower extremities, has 12 individual coil elements arranged in six pairs. We evaluated the performance of a peripheral vascular coil for image quality, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and visual evaluation by comparing it to a body coil using a phantom. RESULTS: SNR with the peripheral vascular coil was 1.5-2.2 times higher than that with the body coil in vertical distance, and 1.6-1.8 times higher in horizontal distance. CNR with the peripheral vascular coil was 2.1-3.8 times higher than that with the body coil. Visual evaluation with the peripheral vascular coil was 1.1-1.2 times higher than with the body coil in spin echo sequences, and 1.2-1.9 times higher in 3D fast spoiled GRASS (3D-FSPGR) sequences. CONCLUSION: The peripheral vascular coil for peripheral MRA is robust and accurate in evaluating peripheral vascular diseases.  相似文献   
996.
997.
Aims/IntroductionWe investigated the association between gestational diabetes mellitus (GDM) and perinatal outcomes stratified by pre‐pregnancy body mass index (BMI) and/or gestational weight gain (GWG).Materials and MethodsData from the national birth cohort in the Japan Environment and Children''s Study from 2011 to 2014 (n = 85,228) were used. Japan uses the GDM guidelines of the International Association of Diabetes and Pregnancy Study Groups. The odds ratios (ORs) of perinatal outcomes were compared between women with and those without GDM.ResultsThe OR (95% confidence interval) of having a small for gestational age infant in the GDM group with a pre‐pregnancy BMI of ≥25.0 kg/m2 and insufficient GWG (<2.75 kg) was 1.78 (1.02–3.12). The OR of having a large for gestational age infant of the same BMI group with excessive GWG (>7.25 kg) was 2.04 (1.56–2.67). The OR of hypertensive disorders of pregnancy was higher in women with a BMI ≥18.5 kg/m2 in the GDM group than in the non‐GDM group.ConclusionsLarge for gestational age and hypertensive disorders of pregnancy were associated with pre‐pregnancy BMI and GWG in either normal weight or overweight/obese women, and the relationship was strengthened when GDM was present. Women with GDM and a BMI of ≥25.0 kg/m2 are at risk of having small for gestational age and large for gestational age infants depending on GWG.  相似文献   
998.
Solid-pseudopapillary tumors of the pancreas(SPTs) are comparatively rare and have low malignancy,with a predilection for young women.Diagnosis is difficult when a SPT develops in a boundary region with other organs.Here,we report a 42-year old woman with a SPT of the pancreas mimicking a submucosal tumor of the stomach on imaging.She was admitted to our hospital complaining of abdominal pain.We suspected a submucosal tumor of the stomach from the f indings of endoscopy,endoscopic ultrasonography and abdominal computed tomography.However,angiography showed that some of the tumor vessels arose from the pancreas.Intraoperative f indings revealed the tumor originated from the pancreas.Therefore,distal pancreatectomy was performed.The pathological diagnosis was SPT of the pancreas.  相似文献   
999.
Although radiation enteritis is a well-recognized sequel of therapeutic irradiation, the standard surgical method is not universally agreed upon. Not only the short-term effect but also the long-term effect after a surgical intervention has been fairly well reported. To reassess the surgical therapy for radiation enteritis, we retrospectively analyzed 48 patients (5 males and 43 females, mean age 58.6 years) who had been operated on in our department. These patients were divided into two types according to the time of surgery or the clinical manifestation, and operative methods were analyzed. Patient’s status such as bowel movement, body weight, and serum albumin value after surgery were analyzed, together with the patients survival. Our surgical methods were small intestinal resection for the intestinal obstruction, and pull-through reconstruction for proctitis. Two patients died of multiple organ failure caused by perforated peritonitis irrespective of emergent operation. Although the overall morbidity was 21.7%, there was no leakage when bowels were anastomosed. Overall survival after radiation-related complication in patients without previous neoplastic disease recurrence was 89%, 79%, and 69%, at 1, 3, and 5 years after surgery, respectively. Bowel motility, serum albumin level, and body weight recovered gradually soon after the operation and reached satisfactory levels within 6 months. Our analysis showed that small bowel injury should be treated by generous resection of the affected bowel followed by careful anastomosis of the disease-free ends, while rectal resection is best dealt with by restorative proctectomy. This may provide a good quality of life and minimize major postoperative complications such as leakage.  相似文献   
1000.
We herein describe the case of a 48-year-old man who presented to our hospital with abdominal distension and pain. Preoperative studies including abdominal ultrasonography and computed tomography failed to determine the cause of the pain. At laparotomy, a giant cystic tumor of the small bowel mesentery was found. Histologically, the tumor was diagnosed as a cystic lymphangioma. Although mesenteric lymphangiomas are rare, especially in adults, they should be considered as a possible cause of acute abdomen. Received: August 8, 2001 / Accepted: January 8, 2002  相似文献   
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