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1.
The hemodynamics in balloon occluded arterial infusion therapy (BOAI) for intrapelvic malignant neoplasms is not totally understood. A new technique to evaluate the perfusion pattern of anticancer drugs under BOAI, which is named Subtraction CT with Low-flow-rate Arterial injection (S-CTLA), has been developed by us. In this technique, spiral CT data were acquired twice, before and after low-flow-rate (0.2 ml/sec) injection of contrast agent. Then, subtraction images were reconstructed. S-CTLA was performed in 3 patients with urinary bladder cancer. Our results provided demonstrable images as well as useful information in predicting the effectiveness of BOAI.  相似文献   

2.
The aim of this study was to develop a standardized non-helical-CT protocol including head, body and proximal extremities in order to achieve a good time efficiency and diagnostic accuracy in the initial radiological evaluation of the multitraumatized patient. A total of 111 circulatory stable blunt trauma patients, brought in to a trauma level II-III hospital, were examined according to a standardized CT protocol. After examining the head with contiguous 10-mm slices without i.v. contrast medium injection, the trunk was examined with 10-mm slices every 30 mm through thorax-abdomen-pelvis with i.v. contrast medium enhancement (occasionally modified). All data in the medical reports were collected and used as "end-point", and the outcome of the CT examination was compared with this final diagnosis. Mean examination time was 20 min (range 12-32 min). In total, 55 head injuries, 89 thoracic injuries, 27 abdominal/pelvic injuries and 62 fractures were found. Computed tomography correctly identified the injuries, except one brain stem injury, one contusion/rupture of the heart, one hepatic injury, two intestinal injuries, eight vertebral injuries and one joint dislocation. A standardized non-helical-CT examination of the head and body may be achieved in 20 min. Its diagnostic accuracy was high, except for vertebral column injuries, which is why we recommend it as the method of choice for initial radiological examination of multitraumatized patients. When available, helical scanning would improve both examination speed and accuracy.  相似文献   

3.
A 53-year-old female was admitted to our hospital after right hydronephrosis was found on the CT scan taken at another hospital. The urinary cytology and culture findings as well as the urinary culture for acid-fast bacilli results were all negative. At our hospital, CT scan revealed a thickening of the right ureteral wall, and right hydronephrosis. In spite of the fact that retrograde pyeloureterography showed a right ureteric obstruction at the ureterovesical junction, cystoscopic examination demonstrated a normal bladder. Since right lower tract carcinoma was suggested, we performed right nephroureterectomy with bladder cuff. Histopathological diagnosis, however, revealed renal and ureteral tuberculosis.  相似文献   

4.
OBJECTIVE: The goals of this study were to define the distinguishing characteristics and frequency of urinary bladder pseudolesions that are produced as opacified urine enters the bladder during contrast-enhanced helical CT of the abdomen and to evaluate the usefulness of delayed imaging in differentiating pseudolesions from true lesions. SUBJECTS AND METHODS: Contrast-enhanced routine CT scans of 184 patients were obtained prospectively. For each patient, we also obtained 5-min delayed images of the bladder. The images were evaluated for apparent focal thickening or polypoid lesions involving the bladder wall, findings that may represent bladder neoplasia, without knowledge of the indications for the scan, the patient's clinical history, or the patient's diagnosis. Apparent lesions that were visible on routine images and entirely absent on delayed images were considered to be pseudolesions. RESULTS: Apparent lesions were identified on 20 (10.9%+/-4.5% [limits of the 95% confidence interval]) of the routine CT scans. Using delayed images, the 21 apparent lesions in these 20 patients were resolved as 13 pseudolesions and eight true lesions. Pseudolesions were present in 6.5%+/-3.6% of patients. CONCLUSION: Pseudolesions of the bladder that are indistinguishable from true lesions pose a significant clinical problem in routine contrast-enhanced helical CT of the abdomen. Delayed imaging of the bladder is useful in distinguishing pseudolesions from true lesions.  相似文献   

5.
Computed tomography (CT) excretory urography was performed in five adult female dogs after intravenous injection of a bolus of four different doses of water-soluble iodinated contrast medium (100, 200, 400, and 800 mgI/kg). CT images centered over the urinary bladder were performed before injection and 1, 3, 5, 7, 9, 11, 15, 20, 25, 30, 40, 50, and 60 minutes after injection. Opacification of both ureters was evaluated by measuring maximum CT number of individual ureters at each time. Time opacification curves were generated for each dose. Best opacification of the ureters was obtained with 400 and 800 mgI/kg, with a constant peak at 3 minutes and durable opacification for 1 hour. Insufficient opacification was obtained with lower dose of 100 and 200 mgI/kg.  相似文献   

6.
OBJECTIVE: The purpose of this study was to evaluate a recently developed hardware and software system for CT scanning that generates images in real time and switches to helical CT scanning by either a visual cue or a region of interest (ROI) amplitude threshold. SUBJECTS AND METHODS: We randomly and prospectively divided 120 abdominal CT examinations into three groups. Two groups received 75 ml of contrast agent at 1.5 ml/sec. Helical CT scanning began after visualization of the contrast bolus arrival in the hepatic veins (visual cue triggering) (39 patients) or after reaching an ROI threshold (automated ROI threshold triggering) (39 patients). A third group served as a control group (42 patients) and received 150 ml of contrast agent at 1 ml/sec. Quality of hepatic enhancement was assessed objectively and subjectively. Comparisons were made after stratifying each group into three weight classes. RESULTS: Errors occurred in 12 (31%) of 39 examinations in the group with automated ROI threshold triggering. In that group, we found a significantly (p < .04) lower mean hepatic enhancement in two of three weight categories, and a significantly (p < .04) lower mean subjective scan quality in one of three weight categories, than we found in the group with visual cue triggering. CONCLUSION: Optimizing portal venous phase helical CT of the liver after a low-volume bolus of contrast agent and an injection rate of 1.5 ml/sec is best achieved by initiating helical CT scanning after visualizing the contrast bolus arrival within the liver rather than after reaching a preset attenuation threshold.  相似文献   

7.
We applied helical CT to examinations of the clinical image diagnosis. Scanning was performed continuously while the couchtop of the CT scanner was shifted at a constant speed. The entire lung field could be scanned during a single holding of the breath when the couchtop speed was 20 mm/s. Tumors as small as 2 mm were detected. The diagnostic detectability and accuracy of helical CT were far superior to those conventional chest radiography. During abdominal examination, the target organ could be scanned at any specified phase (preferably arterial) during the injection of contrast medium. We detected very small hepatic tumors which could not be detected by conventional CT. Helical CT produced continuous data, which was reconstructed to display three-dimensional image. Helical CT could be used in mass screening for the detection of early lung cancer and in computer-aided diagnosis.  相似文献   

8.
The reliability of helical CT as sole preoperative diagnostic technique for abdominal aortic aneurysms (AAA) and its accuracy in detecting vascular anomalies in the abdominal region was evaluated retrospectively in 42 patients with asymptomatic AAA > 40 mm. A single breath-holding helical scan was performed with 5 mm slice thickness, during a single injection of contrast medium, resulting in a 20 cm z-axis coverage. Axial images were reconstructed and used to generate high quality multiplanar reformatted images. Digital subtraction angiography (DSA) was performed in the first 18 patients and then in case of associated peripheral vascular disease (6 patients). Helical CT exactly showed, in all cases, the proximal and distal extent of the AAA. The visceral vessels as well as the inferior vena cava and renal veins were always clearly depicted, showing anatomical variants or pathological involvement in 19 patients. DSA gave sufficient details on the distal run-off but did not allow a reliable visualization of the visceral branches, venous anomalies and true extent of AAA. In our experience helical CT should be considered as the sole method for preoperative imaging of AAA. It allows a complete and precise evaluation; it is fast, with low doses of radiations and does not require hospitalization.  相似文献   

9.
Endoluminal virtual computed tomographic (CT) cholangiopancreatoscopic views of the pancreatic and common bile ducts were generated in 16 patients by using helical CT data sets and endoscopic three-dimensional reconstruction images. In all patients with ductal dilatation, virtual images were obtained and findings correlated with those at helical CT and endoscopic retrograde cholangiopancreatography. Virtual CT cholangiopancreatoscopy is a feasible technique, and initial experience shows promising results.  相似文献   

10.
OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.  相似文献   

11.
Eighty-one consecutive flexible cystoscopic examinations were performed on 69 patients with spinal cord injury (SCI) at the time of their urodynamic study. The indications for cystoscopy included hematuria, recurrent urinary tract infections, symptoms of bladder outlet obstruction, the presence of an intraurethral sphincter stent requiring evaluation, neurogenic vesical dysfunction requiring endourodynamic study (cystometrogram through the working port of the flexible cystoscope), or bladder calculi. Flexible cystoscopy was accomplished in all patients, whether lying supine or seated in a wheelchair (N = 16). Only 6 of 39 patients with previous episodes of autonomic dysreflexia became hypertensive during cystoscopy. When a urodynamic catheter could not be inserted, the flexible cystoscope was particularly useful in defining the urethral anatomy or obstruction and in performing endourodynamic evaluation. The only complication was the development of febrile urinary tract infection in four patients. The flexible cystoscope is a valuable tool in the urodynamic laboratory caring for patients with SCI and is effective for use in endourodynamics, especially when patient positioning or catheter placement is difficult. The procedure is well tolerated, causes minimal stimulation leading to the development of autonomic dysreflexia, and provides accurate cystometric data.  相似文献   

12.
PURPOSE: To assess the effect of the injection rate of contrast medium on pancreatic and hepatic enhancement at abdominal helical computed tomography (CT). MATERIALS AND METHODS: Sixty-four contrast medium-enhanced abdominal helical CT scans (64 adult patients) were obtained with 150 mL of contrast medium. The injection rate was 2.5 mL/sec for the first 32 scans and 5.0 mL/sec for the remaining 32. Scans were obtained at 5-sec intervals, with an intermediate 8-sec breathing interval. Hepatic and pancreatic enhancement levels were measured and averaged, and time-attenuation curves were plotted for both groups. Differences in weight, age, time to peak pancreatic and hepatic enhancement, and peak enhancement were assessed with the Student t test. RESULTS: Both peak enhancement and time to peak enhancement were significantly different between the two injection rates (P < or = .002), with faster, more intense hepatic and pancreatic enhancement at the higher rate. At 2.5 mL/sec, the pancreas reached a peak attenuation level of 65 HU at 69 sec, and the liver reached a peak of 58 HU at 87 sec. At 5.0 mL/sec, the pancreas reached a peak attenuation of 84 HU at 43 sec, and the liver reached a peak of 75 HU at 63 sec.  相似文献   

13.
The aim of this study was to investigate the incidence of operative injury to the lower urinary tract after retropubic urethropexy. We prospectively evaluated the incidence of lower urinary tract injury in 97 consecutive patients after pelvic surgery, which included primary Burch retropubic urethropexy. None of the subjects sustained intraoperative injury of the bladder or ureters as evidenced by an intact bladder mucosa and prompt efflux of dye from both ureteral orifices. In our experience, the incidence of lower urinary tract injury with retropubic urethropexy is low. We do not support the routine use of intraoperative cystoscopy with Burch retropubic urethropexy.  相似文献   

14.
Since its inception, CT scan has had a dominant role in hepatic imaging. Recent advances including helical CT scan and bolus-triggered scan initiation software packages have had a significant impact. Issues regarding volume, rate of administration, and type of intravenous contrast are being distilled. Workstations for three-dimensional data reconstructions are producing images that compete with conventional angiography in certain areas, while angiographically assisted CT scan is being refined in others.  相似文献   

15.
An 8-year-old boy presented with dysuria and acute retention of urine. Rectal examination showed a hard mass arising from the prostate. CT scan of the pelvis confirmed the presence of a large prostatic tumor causing bladder outflow obstruction. A provisional diagnosis of pelvic sarcoma was initially made. Biopsy of the tumor mass however, revealed non-Hodgkin's lymphoma of T-cell type. The tumor showed very good response to chemotherapy and the urinary obstruction significantly improved with a week after starting therapy.  相似文献   

16.
PURPOSE: The aim of this study was to evaluate the role of a fast whole body helical CT scanner for primary diagnosis in trauma patients. METHODS: 27 severely injured patients (9 women, 18 men; mean age 43 years) were first examined with a helical CT scanner allowing for digital radiograms up to a length of 1024 mm and continuous helical scans of up to 70 seconds (slice thickness 3 to 10 mm, pitch factor up to 2). The primary CT diagnosis was verified either by x-ray after the CT examination or during the subsequent days, by abdominal ultrasound, by additional CT scans in the following days, and by clinical follow-up. RESULTS: CT showed all clinically relevant injuries of the head, spine, chest, abdomen and pelvis. The diagnosis and classification of vertebral fractures was performed immediately. 4% of the fractures of the extremities and the ribs were not seen primarily. 6% of the injuries were outside the CT scan field. CONCLUSION: Helical CT is a reliable and fast method to obtain vital information and to improve management planning in severely injured patients. It reduces the number of conventional x-ray examinations. In certain cases, additional x-rays of extremity fractures may be required.  相似文献   

17.
Efforts are being made to develop a new type of CT system that can scan volumes over a large range within a short time with thin slice images. One of the most promising approaches is the combination of helical scanning with multi-slice CT, which involves several detector arrays stacked in the z direction. However, the algorithm for image reconstruction remains one of the biggest problems in multi-slice CT. Two helical interpolation methods for single-slice CT, 360LI and 180LI, were used a starting points and extended to multi-slice CT. The extended methods, however, had a serious image quality problem due to the following three reasons: (1) excessively close slice positions of the complementary and direct data, resulting in a larger sampling interval; (2) the existence of several discontinuous changeovers in pairs of data samples for interpolation; and (3) the existence of cone angles. Therefore we have proposed a new algorithm to overcome the problem. It consists of the following three parts: (1) optimized sampling scan; (2) filter interpolation; and (3) fan-beam reconstruction. Optimized sampling scan refers to a special type of multi-slice helical scan developed to shift the slice position of complementary data and to acquire data with a much smaller sampling interval in the z direction. Filter interpolation refers to a filtering process performed in the z direction using several data. The normal fan-beam reconstruction technique is used. The section sensitivity profile (SSP) and image quality for four-array multi-slice CT were investigated by computer simulations. Combinations of three types of optimized sampling scan and various filter widths were used. The algorithm enables us to achieve acceptable image quality and spatial resolution at a scanning speed that is about three times faster than that for single-slice CT. The noise characteristics show that the proposed algorithm efficiently utilizes the data collected with optimized sampling scan. The new algorithm allows suitable combinations of scan and filter parameters to be selected to meet the purpose of each examination.  相似文献   

18.
OBJECTIVE: To compare the Bard BTA (bladder tumour antigen) test with voided urine cytology (VUC) in the diagnosis of recurrent bladder cancer (BC). METHODS: Urine specimens for the BTA test and VUC were collected on the same day as before cystoscopy from patients undergoing routine surveillance cystoscopy for recurrent BC. The pathologists performing VUC were blinded to the results of the BTA test. RESULTS: BC was identified by cystoscopy and biopsy in 39 of 164 study participants. The overall sensitivities of the BTA test and VUC were 54 and 28%, respectively (p < 0.05). The BTA test was more sensitive than VUC for all tumour stages and grades. For > or = T2 tumours and grade 3 tumours, respectively, the difference was statistically significant (p < 0.05). The specificities of the BTA test and VUC were 92 and 97%, respectively. Both a false-positive BTA test and VUC were found to predict recurrence. CONCLUSION: The BTA test is equal or superior to VUC in the detection of BC in patients undergoing routine surveillance for recurrent BC.  相似文献   

19.
OBJECTIVE: The aim of this study was to compare the diagnostic accuracy of two-dimensional (2D) CT colonography and three-dimensional (3D) virtual colonoscopy with conventional colonoscopy in patients who have suspected colorectal neoplasms. SUBJECTS AND METHODS: Twenty patients were studied (eight women and 12 men; mean age, 53 years; range, 42-85 years). All patients had findings on conventional colonoscopy suggestive of colorectal carcinoma and underwent colonic CT within 3 hr of endoscopy. Two-dimensional CT colonography and 3D virtual colonoscopy images were generated from the same data set that was obtained from thin-section helical CT of the abdomen and pelvis after rectal insufflation of room air. Three-dimensional virtual colonoscopy images were obtained by downloading CT data to a workstation equipped with commercially available software. Volume- and perspective-rendering techniques were used to achieve interactive, 3D virtual "fly-through" examinations of the colonic mucosa. The results of 2D CT colonography and 3D virtual colonoscopy were compared with the findings of conventional colonoscopy and correlated with surgical and pathologic outcome where possible. RESULTS: Twenty masses (defined as intraluminal projections 2 cm or larger in diameter) and 15 polyps (defined as projections smaller than 2 cm in diameter) were identified in our study group. All masses and 14 of 15 polyps were successfully shown on 2D colonography. Three findings of polyps on 2D colonography were false-positive, and one was false-negative. Three-dimensional virtual colonoscopy revealed 19 of 20 masses and 13 of 15 polyps. On conventional colonoscopy, all 20 masses and 13 of 15 polyps were identified, with one false-positive finding of a malignant stricture in a normal colon. Complete examination of the colon was possible in 18 of 20 patients using the 2D technique and in 17 of 20 patients using 3D virtual colonoscopy, whereas conventional colonoscopy showed the entire colon in only 12 of 20 patients. CONCLUSION: Two-dimensional CT colonography and 3D virtual colonoscopy are complementary and effective techniques for examining the colon in patients with suspected colorectal carcinoma. CT techniques offer several advantages over conventional colonoscopy including the ability to detect abnormalities proximal to obstructing carcinomas, accurate localization of abnormalities within the colon, and good patient tolerance. These CT techniques may play an important role in future diagnosis of colorectal cancer and for screening patients at risk.  相似文献   

20.
With faster CT scanners, asymmetric/heterogeneous enhancement (ASHE) of the internal jugular veins (IJVs) is frequently encountered in the absence of pathology. We investigated the frequency, side, pattern and significance of ASHE in 200 patients with various head and neck lesions. Non-ionic contrast medium (300 mgI/ml) was infused into a forearm vein (right, n = 100); left, n = 100). Forty seconds after contrast medium injection, contiguous 5-mm-thick sections were obtained craniocaudally from the skull base to the aortic arch. CT machines with two different scanning cycle times (3 s, n = 100; 2 s, n = 100) were used. ASHE of the IJVs was observed in 51 patients (25.5%); the patient group receiving a right-sided injection with a 2-s scan cycle machine, showing a higher frequency (44%). ASHE was divided into four patterns: homogeneous low density, focal low density, heterogenous opacification and fluid-fluid level formation. ASHE was frequently observed in routine contrast-enhanced CT of the head and neck. Frequency of ASHE increased when the scanning cycle was shorter. We should be aware of this phenomenon to avoid its misinterpretation as venous thrombosis or other pathology.  相似文献   

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