Value of computed tomography of the abdomen and chest in investigation of Cushing's syndrome.

Computed tomography (CT) scans were performed on 37 patients with biochemically proved Cushing''s syndrome to evaluate the role of CT in the investigation of this condition. CT rapidly and correctly identified all 15 adrenocortical tumours, distinguishing five carcinomas from the 10 adenomas. In ACTH-dependent Cushing''s syndrome appreciable bilateral adrenal enlargement was common in patients with an ectopic source (6 of 10 cases), while those with a pituitary source usually had normal sized adrenals (9 of 10). Two patients with a history of over seven years had bilateral adrenal nodules. CT was more accurate in locating a primary ectopic source of ACTH (5 of 12 cases) than any other technique and was particularly valuable in detecting small (less than 1.5 cm) peripheral lung carcinoid tumours which may be undetectable by conventional x-ray techniques. Its speed, accuracy, and simplicity make CT the technique of choice both to show the adrenal anatomy and to locate a suspected ectopic ACTH-secreting tumour in patients with proved Cushing''s syndrome.     

Spiral computed tomography in the diagnosis of gunshot wounds of the abdomen and pelvis

Spiral computed tomography (SCT) in combination with SCT angiography with the rapidity and low-invasiveness of the study yields necessary information and minimizes the number of diagnostic measures in severely wounded patients, by substantially reducing the preoperative period of their examination. The assessment of findings, the processing of data, and the construction of additional repairs do not require the presence of the patient and may be made in later periods. If required, repeated studies make it possible to evaluate the time course of postoperative changes, to identify complications of wound disease at the right time, and to optimize surgical treatment policy. Thus, SCT for fighting gunshot abdominal injury may significantly amplify and, in many cases, substantiate for the existing radiation diagnostic techniques.     

Spiral computed tomography in the diagnosis of the abdomen gunshot wounds and their complications

The results of studies by spiral computed tomography (SCT) in 62 patients with abdominal wounds were analyzed at the Main Military Clinical Hospital of Internal Forces, Ministry of Internal Affairs of Russia. The main contingent of the wounded included active servicemen who had been wounded in the areas of local conflicts, military men. The studies were conducted on days 2 to 15 of their receiving a wound. The potentialities of the technique in evaluating damages to abdominal organs, retroabdominal space, bony structures, in assessing the topography of foreign bodies are described. SCT was compared with classical X-ray and ultrasound studies, laparocentesis which are traditionally used in the diagnosis of gunshot injury. In the authors' opinion, SCT has become the method of choice in the diagnosis of gunshot injury to the abdomen and its complications today.     

Elimination of biological and physical artifacts in abdomen and brain computed tomography procedures using filtering techniques

IntroductionMedical images are usually affected by biological and physical artifacts or noise, which reduces image quality and hence poses difficulties in visual analysis, interpretation and thus requires higher doses and increased radiographs repetition rate.ObjectivesThis study aims at assessing image quality during CT abdomen and brain examinations using filtering techniques as well as estimating the radiogenic risk associated with CT abdomen and brain examinations.Materials and MethodsThe data were collected from the Radiology Department at Royal Care International (RCI) Hospital, Khartoum, Sudan. The study included 100 abdominal CT images and 100 brain CT images selected from adult patients. Filters applied are namely: Mean filter, Gaussian filter, Median filter and Minimum filter. In this study, image quality after denoising is measured based on the Mean Squared Error (MSE), Peak Signal-to-Noise Ratio (PSNR), and the Structural Similarity Index Metric (SSIM).ResultsThe results show that the images quality parameters become higher after applications of filters. Median filter showed improved image quality as interpreted by the measured parameters: PSNR and SSIM, and it is thus considered as a better filter for removing the noise from all other applied filters.DiscussionThe noise removed by the different filters applied to the CT images resulted in enhancing high quality images thereby effectively revealing the important details of the images without increasing the patients’ risks from higher doses.ConclusionsFiltering and image reconstruction techniques not only reduce the dose and thus the radiation risks, but also enhances high quality imaging which allows better diagnosis.     

Value of computed tomography in patients with stroke: Oxfordshire Community Stroke Project.

The usefulness of computed tomography (CT) was assessed in 325 consecutive patients with a "clinically definite first stroke" from a community stroke register. CT detected five "non-stroke" lesions (two cerebral gliomas, one cerebral metastasis, and two subdural haematomas), a frequency of 1.5%. Five patients were identified with cerebellar haemorrhage, but only one survived long enough to have a CT scan. CT was useful in excluding intracranial haemorrhage as the cause of the stroke in four patients receiving anticoagulants and seven receiving antiplatelet treatment; it showed intracranial haemorrhage in one patient taking aspirin. Forty six patients were in atrial fibrillation at the time of their stroke; four had intracranial haemorrhages and three had haemorrhagic cerebral infarcts. Nineteen patients with presumed ischaemic minor stroke were considered suitable for carotid endarterectomy; CT showed small haemorrhages in two. The CT scan provides very useful information in a minority (up to 28%) of patients with first stroke, who can be selected on quite simple criteria: (a) doubt (usually because of an inadequate history) whether the patient has stroke or a treatable intracranial lesion; (b) the possibility of cerebellar haemorrhage or infarction; (c) the exclusion of intracranial haemorrhage in patients who either are already taking or likely to need antihaemostatic drugs or are being considered for carotid endarterectomy; (d) if the patient deteriorates in a fashion atypical of stroke.     

Cranial computed tomography in infants and children.

Cranial computed tomography has been performed in adults for the past 2 years but relatively few children have undergone this procedure. The specific uses in children are in detecting intracranial mass lesions and identifying the character of the lesion, and evaluating congenital cranial diseases such as cerebral dysplasia, tuberous sclerosis and leukodystrophies. This safe, rapid, noninvasive technique will soon replace or supplement standard neuroradiologic techniques in infants and children.     

The immunological hazard of Cushing's syndrome.

A 24-year-old woman was found to have cryptococcal meningitis and Cushing''s syndrome due to an adrenal adenoma. Her meningitis was successfully arrested with fluorouracil. Treatment with metyrapone decreased her cortisol production and produced clinical remission of Cushing''s syndrome. On admission her peripheral T lymphocytes were few and hyporeactive. When the overproduction of cortisol ceased the numbers of T lymphocytes and their reactivity returned to normal and she developed in-vitro lymphocyte responsiveness to the cryptococci.     

The role of perfusion computed tomography in the prediction of cerebral hyperperfusion syndrome

Background

Hyperperfusion syndrome (HPS) following carotid angioplasty with stenting (CAS) is associated with significant morbidity and mortality. At present, there are no reliable parameters to predict HPS. The aim of this study was to clarify whether perfusion computed tomography (CT) is a feasible and reliable tool in predicting HPS after CAS.

Methodology/Principal Findings

We performed a retrospective case-control study of 54 patients (11 HPS patients and 43 non-HPS) with unilateral severe stenosis of the carotid artery who underwent CAS. We compared the prevalence of vascular risk factors and perfusion CT parameters including regional cerebral blood volume (rCBV), regional cerebral blood flow (rCBF), and time to peak (TTP) within seven days prior to CAS. Demographic information, risk factors for atherosclerosis, and perfusion CT parameters were evaluated by multivariable logistic regression analysis. The rCBV index was calculated as [(ipsilateral rCBV - contralateral rCBV)/contralateral rCBV], and indices of rCBF and TTP were similarly calculated. We found that eleven patients had HPS, including five with intracranial hemorrhages (ICHs) of whom three died. After a comparison with non-HPS control subjects, independent predictors of HPS included the severity of ipsilateral carotid artery stenosis, 3-hour mean systolic blood pressure (3 h SBP) after CAS, pre-stenting rCBV index >0.15 and TTP index >0.22.

Conclusions/Significance

The combination of severe ipsilateral carotid stenosis, 3 h SBP after CAS, rCBV index and TTP index provides a potential screening tool for predicting HPS in patients with unilateral carotid stenosis receiving CAS. In addition, adequate management of post-stenting blood pressure is the most important treatable factor in preventing HPS in these high risk patients.     

The discriminatory value of the low-dose dexamethasone suppression test in the investigation of paediatric Cushing's syndrome

BACKGROUND: Low- and high-dose dexamethasone suppression tests (LDDST, HDDST) are used in the investigation of Cushing's syndrome (CS). In adults with Cushing's disease (CD), cortisol suppression during LDDST predicts suppression during the HDDST. METHODS: We reviewed the results of the LDDST (0.5 mg 6 hourly x 48 h), HDDST (2.0 mg 6 hourly x 48 h) and corticotrophin-releasing hormone (CRH) test in 32 paediatric patients with CS: 24 had CD, 1 ectopic ACTH syndrome, 5 nodular adrenal hyperplasia and 2 adrenocortical tumours. Results: In CD, LDDST suppressed cortisol from 590.7 +/- 168.8 (mean +/- SD) to 333.7 +/- 104.0 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 45.1%; CI (30.8, 59.4%); 16/24 (66%) suppressed >30%; mean suppression 68.1%, CI (58.1, 77.9%)). The HDDST suppressed cortisol from 596.3 +/- 174.5 to 47.1 +/- 94.8 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 93.5%; CI (88.2, 98.8%) with 17/24 (71%) suppressing to <50 nmol/l and 100% to <50% of baseline). In the LDDST, suppression correlated with that during the HDDST (r = +0.45, p < 0.05) with >30% suppression predicting that in the HDDST and hence CD. CRH increased cortisol by +100.3% (CI 62, 138.5%), 22/24 (91.7%) showing a >20% increase. In the other CS pathologies (n = 8) the LDDST induced no significant decrease in cortisol. CONCLUSION: The LDDST was of diagnostic value by discriminating between CD and other CS aetiologies. In our view the HDDST is redundant in the investigation of paediatric CS.     

Five cases of cyclical Cushing's syndrome.

Reported cases of cyclical Cushing''s syndrome are rare. Of 14 successive patients with Cushing''s syndrome nine collected sequential urine samples for the estimation of cortisol:creatinine ratio. Five had cyclical Cushing''s syndrome while two had considerable variation in urinary cortisol excretion without a cyclical pattern being established. Two of the five patients with a cyclical syndrome had paradoxical responses to dexamethasone. In only one patient with a cyclical pattern did the cortisol:creatinine ratio fall after treatment with bromocriptine or cyproheptadine, or both. The high incidence of the cyclical form of Cushing''s syndrome has important clinical implications. A high index of suspicion of the syndrome is required in patients with symptoms or signs of Cushing''s syndrome but with normal cortisol values, in patients with fluctuating cortisol values, and in patients with anomalous responses to dexamethasone. Because of possible variations in steroidogenesis the results of drug studies in Cushing''s syndrome must be interpreted cautiously.     

Cushing's syndrome in childhood

A patient with Cushing''s syndrome whose clinical manifestations began at approximately 9 years of age was followed for a period of four years. Initial laboratory studies revealed urinary 170HCS and 17 KS levels which were elevated for her age, with a normal diurnal variation of plasma cortisol and normal suppression of urinary 170HCS by 1.5 mg. of dexamethasone daily. It was not until four years after the onset of the disease that laboratory studies unequivocally supported the diagnosis of Cushing''s syndrome resulting in definitive therapy. Clinical features consisted primarily of cessation of growth, obesity, and hirsutism, with no evidence of protein depletion. It is suggested that the clinical and laboratory features of Cushing''s syndrome in childhood may present differences from those found in the adult. Failure to recognize these differences may result in delay in therapy with subsequent persisting stigmata of the disorder.     

Computed tomography of abdomen in staging and clinical management of lymphoma.

During July 1976 to Demember 1977, 150 patients with Hodgkin''s disease and 138 with non-Hodgkin''s lymphoma were examined by computed tomography (CT). In 45 cases 50 repeat examinations were conducted. Concurrent laparotomy and lymphography were performed on 68 and 56 patients respectively. The overall incidence of false-positive CT examinations as confirmed by laparotomy was 7.4%. In 18 patients with non-Hodgkin''s lymphoma in the abdomen there was good correlation between the two techniques. Of the 50 patients with Hodgkin''s disease who underwent laparotomy, 17 had splenic disease and 14 minimally enlarged lymph nodes in 20 areas; CT, however, detected only four diseased spleens and five minimally enlarged lymph nodes. Nevertheless, CT often detected enlarged lymph nodes missed by lymphography and was 23% more efficient than lymphography in detecting unsuspected disease. CT also detected unsuspected disease in patients with relapse of lymphoma. CT may replace other non-invasive investigations of abdominal disease in patients with lymphoma and give a reliable guide to prognosis. It does not, however, eliminate the need for laparotomy in staging Hodgkin''s disease.     

Computed tomography in the investigation of dementia.

To assess the value of computed tomography in investigating patients with dementia, 500 consecutive patients presenting with a provisional clinical diagnosis of dementia of recent onset were reviewed and the results analysed in a computer. Most patients had either cerebral atrophy or infarction, but 82 patients had a normal scan and 42 others had tumours. More than 10% of all patients, including 5% with no other symptoms or signs, had a treatable lesion. Various associated symptoms and signs were useful pointers to such a treatable lesion and clearly indicated computed tomography. Accurate diagnosis is the cornerstone of proper management, and if a few patients with treatable lesions can be identified then the benefits to all concerned may be incalculable.