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Clinical utility of abdominal CT scanning in patients with HIV disease.

AIM: To evaluate the yield of abdominal computed tomography (CT) in patients with human immunodeficiency virus (HIV) infection and to assess the influence of CT scanning on patient management and diagnosis. METHOD: A retrospective analysis of 216 abdominal CT scans, performed on 156 patients (147 men, nine women; age range 22-57 years), between March 1992 and October 1994 was undertaken. Clinical information, including the indication for performing the scan and the eventual diagnosis, was obtained from the case notes and the contribution of CT scanning to patient management assessed. RESULTS: Indications for CT fell into five main groups: investigation of pyrexia of unknown origin (PUO) (n = 82), staging and response to treatment of previously diagnosed neoplasms (n = 46), investigation of abdominal pain (n = 20), CT undertaken to clarify the results of other imaging investigations (n = 20) and miscellaneous indications (n = 48). An eventual diagnosis thought to account for the clinical presentation was made in 150 cases (68%), reflecting the high level of underlying pathology. CT contributed to patient management in a large proportion of cases (62%), but only led directly to a diagnosis in a minority (12%). CONCLUSION: With the exception of patients presenting with PUO, abdominal CT remains an important investigation in the management of patients with HIV infection. In patients presenting with PUO a thorough infection screen should be undertaken prior to CT scanning. Whilst frequently contributing to patient management, CT rarely leads directly to a diagnosis.

AIDS-Related Opportunistic Infections↗

Indications for surgical treatment of putaminal hemorrhage. Comparative study based on serial CT and time-course analysis.

Serial computerized tomography (CT) scans were correlated with a precise time-course analysis of the neurological condition of 180 patients with hypertensive putaminal hemorrhage. All patients entered the study within 3 hours of the ictus. In this series, 111 patients were treated conservatively and 69 surgically. The neurological condition of each patient was measured by means of a newly proposed grading system for intracerebral hemorrhage-intracranial hemorrhage (ICH grade) which is a modification of the Glasgow Coma Scale. Serial CT scans revealed that most hemorrhages were completed within 6 hours after ictus. Based on the ICH grade at 6 hours postictus, a clinical classification of the severity of putaminal hemorrhage was defined: fulminant, rapidly progressive, slowly progressive, and nonprogressive. According to this classification, precise time courses of the ICH grade were compared between the conservative and surgical treatment groups in a 7-day postictal period. Activities of daily living at 6 months after ictus were also compared. Surgical treatment for a rapidly progressive hemorrhage appears to be beneficial if undertaken in patients under 65 years of age. Surgery in a slowly progressive hemorrhage should be considered only in a small number of patients who deteriorate neurologically with conservative treatment. In this series of patients, surgical treatment of fulminant and nonprogressive hemorrhage was not likely to improve the quality of life or functional recovery. Regardless of treatment modality, CT provided evidence that patients with anterior capsular hemorrhage (16% in this series) showed good recovery of motor and speech function.

Activities of Daily Living↗

Computed tomographic evaluation of the diaphragmatic crura.

The diaphragmatic crura have a variable appearance on CT body scans. They can at times appear quite prominent and be easily confused with other anatomical or pathological structures. Analysis of the CT scans of 100 patients revealed certain characteristic features of the diagphragmatic crura that help distinguish them from other structures, especially enlarged para-aortic lymph nodes.

Diaphragm↗

194 hepatocellular cancers treated by radiation and chemotherapy combinations: toxicity and response: a Radiation Therapy Oncology Group Study.

Hepatocellular carcinoma is known to have a doubling time of approximately 41 days. This rapid cell division suggested that hyperfractionated radiation and chemotherapy might add an advantage in gaining remission of this malignancy. One hundred and thirty-five patients (70% with metastasis and/or previous treatment) were prospectively treated with single daily fractions to the liver (3.0 Gy external beam radiation, total dose 21.0 Gy), and chemotherapy for hepatocellular carcinoma. The low dose chemotherapy used in conjunction with the radiation was 2 hr before treatment on days 1, 3, 5, and 7 and consisted of Adriamycin, 15 mg IV and 5-FU, 500 mg IV. These patients were compared to a second group of 59 patients (80% with metastases and/or previous treatment) treated using the same chemotherapy regimen but using hyperfractionated whole liver external beam irradiation (1.2 Gy twice daily, 4 hr between treatments, 5 days per week to 24.0 Gy, 10 MV photons). Response was determined by CT scan tumor volumetric analysis. The response rate for the single daily fraction patient group was 22% and for the new hyperfractionated group, 18% (p = 0.68). Toxicity was evaluated by RTOG criteria. The grade 4 hematologic toxicity noted in the daily fraction patient group was 6%. Among 59 patients treated with the hyperfractionated liver irradiation, 2% experienced grade 4 hematologic toxicity. Esophagitis occurred in 1% of patients in the standard fractionation group and 19% in the hyperfractionated group (p = 0.0001). Grade 1-4 thrombocytopenia occurred in 49% of patients in the conventional group and 68% in the hyperfractionated group (p = 0.03). Normal liver volume changes with treatment were measured with CT scan tumor volumetric analysis. The hyperfractionated group experienced a median of 11 cc increase in liver volume and the conventional group a 46 cc decrease, but the difference was not significant. Hyperfractionated radiation did not demonstrate a significant benefit over standard daily radiation, but acute toxicity appeared to be higher.

Antineoplastic Combined Chemotherapy Protocols↗

[Spontaneous hyperdense intracranial vessels seen on CT scan in polycythemia cases].

PURPOSE: A better understanding of the significance of diffuse hyperdensity affecting the circle of Willis and the dural sinuses on unenhanced CT. MATERIALS AND METHODS: We performed a retrospective study of 19 patients with a neurological manifestation and a CT scan without contrast injection. Among these 19 patients, six had been included because of primary or secondary polycythemia. The analysis of cerebral CT scans was made qualitatively by visual inspection and quantitatively. RESULTS: In patients with a hematocrit percentage exceeding 60%, both circle of Willis and dural sinuses were dense on unenhanced CT scans. A linear relation between the hemoglobin level and the contrast of the dural sinuses compared with the grey matter was observed with an excellent correlation (r = 0.934; n < 0.0001; p = 19). CONCLUSION: Increased density of cerebral vessels on unenhanced CT is a sign of a high hemoglobin level.

Adult↗

Age and duration of illness as predictors of ventricular brain ratio (VBR) size in chronic schizophrenic patients. A stepwise regression analysis study.

The CT scans of 18 chronic schizophrenic patients and 17 controls were evaluated for Ventricular Brain Ratio (VBR) size. A trend for the patient group to have larger VBR than controls was present but did not reach statistical significance at the 5% level. Age was found to be an important correlate of VBR within the patient group but not among controls. In a stepwise multiple-regression model age, among other independent variables, can account for 47% of VBR variance in schizophrenic patients. Linear regression analysis did not reveal significant association between VBR and age in control subjects.

Adult↗

Accuracy and significance of computed tomographic scan assessment of hepatic volume in patients undergoing liver transplantation.

BACKGROUND: A small liver volume is considered to be a poor prognostic factor in cirrhosis, often indicative of advanced liver disease. Radiologic assessment of liver volume before liver transplant is routinely performed in many transplant centers. We sought to assess the accuracy and significance of computed tomographic (CT) scanning in hepatic volumetric analysis by correlating CT-derived estimation of liver volume with that of corresponding liver explants. METHODS: A chart review of all patients aged 17 years or older undergoing liver transplant at Mount Sinai Medical Center between 1989 and 1995 was performed. Each patient underwent conventional CT scanning with measurement of liver volume (CTLV). Recipient liver volume (RLV) was defined as weight of liver explant after all attached ligaments, portal structures, and gallbladder were dissected free. Expected liver volume was calculated pretransplant based on age, gender, height, and weight. Patients were categorized into three groups based on etiology of liver disease: (1) hepatocellular (e.g., viral hepatitis, alcohol-related), (2) cholestatic (e.g., primary biliary cirrhosis), and (3) cryptogenic. The ratio of CTLV to RLV was used as a measure of the accuracy of CT volumetric analysis. RESULTS: A total of 579 patients was studied (group 1=376, group 2=139, group 3=64). All three groups were statistically similar with regard to age, prothrombin time and total bilirubin. Median CT liver volume was 1308 ml (range: 338-3847), 1651 ml (range: 641-3861), and 1210 ml (range: 348-2575) in groups 1-3, respectively; median ratio of CTLV to RLV was 1.02 (range: 0.50-2.31), 1.05 (range: 0.52-2.22), and 1.05 (range: 0.50-1.56) for groups 1-3, respectively. When RLV was small, it tended to be overestimated by CTLV. In contrast, when RLV was large, it was often underestimated. Clinical features such as history of esophageal variceal bleed, encephalopathy or ascites, and laboratory data did not influence accuracy of CT volumetric analysis. CONCLUSIONS: CT-derived estimation of liver volume appears to correlate closely with actual weight of liver explant regardless of the etiology of chronic liver disease. With extremes in CT volumetric analysis, actual liver volume tends to be under- or overestimated. For patients with end-stage liver disease, both CT-derived and actual liver volume are greater in cholestatic than in hepatocellular disorders.

Adolescent↗

Centralized multiinstitutional postimplant analysis for interstitial prostate brachytherapy.

PURPOSE: To investigate the feasibility and utility of performing centralized postimplant analysis for transperineal interstitial permanent prostate brachytherapy (TIPPB) by conducting a pilot study that compares the results obtained from 125I implants conducted at five different institutions. METHODS AND MATERIALS: Dose-volume histogram (DVH) analysis was performed on 10 postimplant CT scans from each of five institutions. This analysis included the total implanted activity of 125I, ultrasound, and CT volumes of the prostate, target-volume ratios, dose homogeneity quantifiers, prostate dose coverage indices, and rectal doses. As a result of the uncertainty associated with the delineation of the prostatic boundaries on a CT scan, the contours were redrawn by a single, study center physician, and a repeat DVH analysis was performed. This provided the basis for comparison between institutions in terms of implant technique and quality. RESULTS: By comparing total activity to preimplant ultrasound volume we clearly demonstrated that differences exist in implant technique among these five institutions. The difficulty associated with determining glandular boundaries on CT scans was apparent, based upon the variability in prostate volumes drawn by the various investigators compared to those drawn by the study center physician. This made no difference, of course, in the TVR or homogeneity quantifiers that are independent of target location. Furthermore, this variability made surprisingly little difference in terms of dose coverage of the prostate gland. Rectal doses varied between institutions according to the various implant techniques. CONCLUSIONS: Centralized, outcome-based evaluation of transperineal interstitial permanent prostate brachytherapy is viable and appropriate. Such an approach could be reasonably used in the conduct of multiinstitutional trials used to study the efficacy of the procedure.

Brachytherapy↗

Acute deterioration of a woman following acute pancreatitis with pseudocysts.

BACKGROUND: A 49-year-old white female with a history of acute pancreatitis that was complicated by pseudocysts presented with severe acute-onset abdominal pain of a few hours duration with associated vomiting. Physical examination showed a soft abdomen with mild diffuse tenderness and positive bowel sounds. Initial blood work revealed a drop in her hematocrit, and elevated but stable amylase and lipase levels. A CT scan of the abdomen revealed a splenic artery pseudoaneurysm with extravasation of contrast medium into an adjacent pseudocyst. INVESTIGATIONS: Physical examination, blood analysis and a CT scan of the abdomen with contrast medium. DIAGNOSIS: Splenic artery pseudoaneurysm bleeding into an adjacent pseudocyst. MANAGEMENT: Embolization of the splenic artery across the neck of the pseudoaneurysm.

Acute Disease↗

Giant intracranial aneurysms of the anterior circulation: clinical characteristics and diagnosis by computed tomography.

The computed tomography (CT) characteristics and clinical features of giant (globoid) aneurysms of the anterior circulation are reviewed. These lesions appear on the CT scan as smoothly encapsulated ovoid masses, within which a partially patent lumen is seen after the infusion of iodinated contrast material. With careful analysis of the CT scan it may be possible to differentiate giant internal carotid artery, anterior cerebral artery, and middle cerebral artery aneurysms from other parasellar and hemispheric lesions.

Adult↗

Dosimetric consequences of tumor mobility in radiotherapy of stage I non-small cell lung cancer--an analysis of data generated using 'slow' CT scans.

BACKGROUND: The target coverage for radiotherapy of early-stage lung cancer was evaluated using two different CT techniques. MATERIALS AND METHODS: A conventional planning CT scan and two limited scans of the tumor region were performed in seven patients with peripheral tumors. Three 'slow' scans (slice thickness 4mm, index 3mm, revolution time 4s/slice) were then performed, followed by three-dimensional image registration. Planning target volumes (PTV) were generated using these GTV-PTV margins: (a) 1cm (PTV1.0); (b) 1.5 cm (PTV1.5); and (c) 0.9, 1.0, and 0.9 cm ('PTV(clinical)') when set-up errors are avoided. RESULTS: PTVs derived from three 'slow' scans missed 1.9% of the volume derived from three planning scans for an immobile tumor and 9.3% in the case of a mobile tumor. For an immobile tumor, PTV1.5 achieved comparable coverage to that achieved using PTVclinical, which was generated from three 'slow' scans and a planning scan. For a mobile tumor, PTV(1.5) covered only 89% of the volume captured by PTVclinical. PTV1.0 resulted in inadequate target coverage in all the patients. Reductions in potential lung toxicity (V20) were achievable in six patients despite the larger GTVclinical when treatment set-up errors were minimized. CONCLUSIONS: PTVs derived using 'slow' CT scans consistently produce superior target coverage than that using conventional scans. This may account for the poor local control observed in stage I lung cancer.

Carcinoma, Non-Small-Cell Lung↗

Tumor location cannot predict the mobility of lung tumors: a 3D analysis of data generated from multiple CT scans.

PURPOSE: There is limited information available on the three-dimensional (3D) motion of lung tumors. Data derived from multiple planning computed tomographic (CT) scans were used to characterize the 3D movement of small peripheral lung tumors. METHODS AND MATERIALS: A total of 29 data sets from patients with Stage I non-small-cell lung cancer (NSCLC), each of which consisted of three "rapid" and three "slow" planning CT scans, were analyzed. All six scans were coregistered, and contoured gross tumor volumes (GTVs) were expanded by 5 mm to derive clinical target volumes (CTVs). Two-dimensional and 3D displacement vectors of the individual CTVs, relative to an "optimal" CTV derived from all six scans, were generated. Tumor mobility was correlated with location. Three-dimensional margins, which had to be added to individual CTVs to ensure coverage of "optimal" CTVs, were determined. RESULTS: No significant correlation was observed between the anatomic location of tumors and the extent of mobility in the x, y, and z axes. However, supradiaphragmatic lesions exhibited more mobility, particularly in the craniocaudal direction. The addition of a 3D margin of 5 mm to a single slow CTV ensured full coverage of the "optimal CTV". CONCLUSIONS: Lung tumors demonstrate significant mobility in all directions, and this did not closely correlate with anatomic location. Individualized assessment of tumor mobility remains necessary, and is possible when the CTV derived from a single slow scan is used for radiotherapy planning.

Carcinoma, Non-Small-Cell Lung↗

[An analysis of findings EEG and brain CT scans in patients with primary hypoparathyroidism].

10 cases of primary hypoparathyroidism showed abnormal findings on EEG. Among them 9 cases were also verified by CT scans. It was considered that the severity of abnormalities in primary hypoparathyroidism was not only influenced by the serum concentration of calcium, but also related with the severity and extent of calcification in the brain. These findings would be of significance with regard to the diagnosis, treatment and prognostic evaluation of primary hypoparathyroidism.

Adolescent↗

CT scanning for functional endoscopic sinus surgery: analysis of 200 cases with reporting scheme.

An analysis of the computed tomograms of the paranasal sinuses from 200 patients with sinonasal complaints is presented. The results of our study are similar to those of other reported series despite a different patient selection. We have developed a simple systematic reporting scheme which includes all of the relevant abnormalities, and which allows a much more detailed picture of the disease pattern to be generated for both clinical use and for analytical studies.

Adolescent↗

[Computerized tomography of the brain in diagnosis of neuroinfections--personal observations].

An analysis of CT-scans of the brain in 55 patients with suspected neuroinfections is presented. All patients were treated at the I Department of Infectious Diseases of the Silesian Academy of Medicine in 1983-1992. Patients were divided into 3 groups. The first group included patients with suppurative meningitis and encephalitis, the second--with aseptic meningitis, and the third group--patients with other CNS diseases. An analysis has shown that CT-scans of the brain are very useful in an early detection of neuroinfections complications and sequelae, especially brain abscess. The author suggests that CT-scans of the brain may also play an important role in differential diagnosis of neuroinfections and other CNS diseases together with clinical symptoms.

Adolescent↗

Clinical utility and cost-effectiveness of routine preoperative computed tomography scanning in patients with colon cancer.

BACKGROUND: The aims of this study were to assess the clinical utility of the practice of routine preoperative CT scanning and to determine its cost-effectiveness in colon cancer patients. METHODS: A 6-year database of colon cancer patients treated at a veterans affairs medical was reviewed to determine the influence of preoperative CT scanning on clinical management. Cost analysis involved comparison of the institutional cost of CT scanning with the cost savings provided by avoiding nontherapeutic operations. RESULTS: CT scans were obtained in 130 consecutive patients. CT scans provided information that was used in treatment planning in 43 (33%) patients and definitively altered the mode of treatment in 21 (16%) patients. The practice saved the institution $24,018 over 6 years. CONCLUSION: Routine preoperative CT scanning definitively alters treatment in a small number of cases and is cost-effective.

Aged↗

[CT scan and clinical diagnosis of parasellar lesions--analysis of 91 cases].

Ninety-one patients with parasellar lesions proved by pathology and surgery from July 1982 to May 1987 and 22 patients misdiagnosed clinically or by CT are reported. The authors found that: 1. Besides the main group of parasellar lesions such as pituitary tumor, meningioma, and craniopharyngioma, some rare disease like glioma, pituitary carcinoma, chordoma, olfactory neuroblastoma, Rathke's pouch and tuberculoma of optic nerve were also found which comprised 12% (11/91) in this series. They should be considered in differential diagnosis; 2. Correct diagnosis was made when CT findings conformed well with the clinical features. Over-emphasis of clinical features or neglect of CT findings should be discouraged as they may lead to erroneous diagnosis; 3. In this series, the highest correct diagnosis rates were: pituitary tumor (95%), parasellar meningioma (78%) and craniopharyngioma (50%). It is difficult to make a correct diagnosis for these rare disease entities before operation; and 4. CT scan cannot completely replace angiography and ventriculography when they are needed for differential diagnosis.

Adult↗

[Neuroimaging characteristics of cerebral infarcts].

Over the last years, technical advances in neuroimaging have allowed drastic improvements in the assessment of acute ischemic cerebral events. Beyond conventional morphological analysis, diffusion-weighted and perfusion-weighted MRI now enable routine functional assessment of brain tissue; spectroscopy and diffusion tensor imaging still remains in the domain of clinical research. During acute ischemia events, diffusion-weighted MRI can detect the movements of water molecules and cytotoxic edema related to cell injury enabling rapid diagnosis and early assessment of cerebral ischemia. In conjunction with perfusion imaging, which detects hypoperfusion areas, diffusion-weighted MRI provides a means to identify areas of penumbra ischemia. More recent multislice computed tomographic (CT) scans with multimodal analysis are also very competitive for assessment of cerebral ischemia (non-enhanced CT, CT angiography and perfusion CT). The purpose of this paper is to describe the CT and MRI patterns during the different stages of cerebral infarcts.

Acute Disease↗