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S A Sohaib

Publications and source records attributed to S A Sohaib.

29 records · Page 2Linked to original sources
PubMed2000

Primary hyperaldosteronism (Conn syndrome): MR imaging findings.

PURPOSE: To describe the magnetic resonance (MR) imaging features of the adrenal glands in primary hyperaldosteronism and assess MR imaging in the detection and characterization of aldosterone-producing adenoma (APA). MATERIALS AND METHODS: The authors retrospectively reviewed the cases of 20 patients (13 female and seven male patients; age range, 14-67 years; median age, 46 years) with primary hyperaldosteronism who underwent 1.5-T MR imaging between 1995 and 1998. All patients underwent transverse T1- and T2-weighted imaging, and chemical shift imaging was performed in 17 patients. Imaging results were correlated with findings at biochemical testing, venous sampling, or surgery. RESULTS: Among the 20 patients, 10 (50%) had APA and 10 (50%) bilateral adrenal hyperplasia (BAH). In the detection of APA, MR imaging had a sensitivity of 70%, specificity of 100%, and accuracy of 85%. APAs (mean size, 20 x 16 mm) were iso- or hypointense relative to the liver on T1-weighted images and slightly hyperintense on T2-weighted images. With chemical shift imaging, the signal intensity decreased on the out-of-phase images in six of seven (86%) patients with APA and in eight of nine (89%) patients with BAH. CONCLUSION: MR imaging has a high specificity in the detection of APA. As with nonhyperfunctioning adenoma, APA and BAH show evidence of intracellular lipid at chemical shift imaging.

Adenoma↗
PubMed2000

CT assessment of tumour response to treatment: comparison of linear, cross-sectional and volumetric measures of tumour size.

Changes in cross-sectional area are currently used to assess tumour response to treatment. The aims of this study were to validate a helical CT technique for volume determination using a series of phantoms and to compare tumour responses indicated by one-, two- and three-dimensional measures of tumour size change in patients treated for germ cell cancer or lymphoma. All studies were performed on an IGE HiSpeed Advantage helical CT scanner with an Advantage Windows workstation. Phantom volumes were calculated using volume reconstruction software and compared with reference volumes determined by water displacement. 20 lymph node masses were studied on serial CT scans in 16 patients treated with chemotherapy for germ cell cancer or lymphoma. For each lesion the maximum diameter, maximum cross-sectional area and volume were determined before and after treatment. Tumour response was assessed using the standard World Health Organisation criteria (i.e. changes in cross-sectional area) and the newly proposed unidimensional response evaluation criteria in solid tumour (RECIST). The CT volume measurement error was 1.0-5.1% for regularly shaped phantoms larger than 35 cm3. In the assessment of treatment response there was 90% agreement between one-dimensional (1D) and two-dimensional (2D) measurements and 100% agreement between 2D and three-dimensional (3D) measurements. CT volume measurements are accurate and reproducible, particularly for larger structures. Assessment of tumour response using 1D, 2D and 3D measures had limited influence on the classification of treatment response. However, the impact of CT assessment of tumour response using 1D, 2D and 3D measurements on clinical decisions and patient outcome remains to be determined.

Adult↗
PubMed1999

Adrenal enlargement and failure of suppression of circulating cortisol by dexamethasone in patients with malignancy.

The aim of this study was to further elucidate the activity of the hypothalamo-pituitary-adrenal (HPA) axis in patients with malignancy and to correlate this with the size of the adrenal glands. Fourteen patients with a variety of malignancies were studied prior to receiving cytotoxic chemotherapy. During routine staging computerized tomographic (CT) scans, the size of the body, medial and lateral limbs of the adrenal glands were measured and compared with those of a normal group of patients studied previously. Measurements of 09:00 h serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels were made before and after the administration of dexamethasone (0.5 mg 6-hourly for 48 h) in addition to the peak cortisol response to i.v corticotropin releasing hormone (CRH). Overall, patients with malignancy had significantly larger adrenal glands than patients without malignancy; those with non-haematological malignancies had larger glands than patients with haematological malignancies. Following dexamethasone to suppress circulating cortisol levels, nine patients (64%) demonstrated abnormal resistance with cortisol levels > 50 nmol l(-1): mean value 294 nmol l(-1) (range 67-1147). Those patients who failed to suppress after dexamethasone had significantly larger adrenal glands than those that did suppress and tended to have non-haematological malignancies. ACTH levels were undetectable or low in three patients in whom it was measured and who did not suppress with dexamethasone. Following CRH, the cortisol levels were highest (823 and 853 nmol l(-1)) in two of these patients. Malignancy is associated with diffuse enlargement of the adrenal glands and resistance to dexamethasone-induced suppression of the HPA axis, which is not due to ectopic ACTH secretion. This disturbance of the normal control of the HPA axis is unexplained and its functional significance remains uncertain.

Adrenal Glands↗
PubMed1999

Computed tomography appearance of the thymus and anterior mediastinum in active Cushing's syndrome.

Computed tomography (CT) evaluation of the thymus and anterior mediastinum is an important aspect of the investigation of patients with ACTH-dependent Cushing's syndrome in order to exclude an ACTH-secreting carcinoid tumor. We have reviewed the CT imaging of the thymus and anterior mediastinum in a series of 85 patients (55 females; median age 41, range 7-77 yr) with active Cushing's syndrome as there are few data on the range of appearances in hypercortisolemic states. One patient had a thymic carcinoid tumor (24 x 18 mm). Of the others, 28/84 (33%) patients showed thymic remnant tissue, consisting of either nodule(s) at least 5 mm diameter (n = 21, mean diameters 12.5 +/- 5 x 9.6 +/- 4 mm), or triangular bilobed glands (n = 7, mean thickness of the body, right and left limbs 25 +/- 7, 14 +/- 3, and 12 +/- 5 mm). Thymic involution appeared in 56/84 (67%) patients, ranging from small nodule(s) of less than 5mm diameter to linear soft tissue strands and complete fatty replacement. Patients with thymic remnant tissue were younger than those with thymic involution (P < 0.05). The thymic carcinoid tumor could be distinguished from remnant tissue on the basis of age and size. The presence of anterior mediastinal nodule(s) in hypercortisolemia need not imply the presence of a thymic carcinoid tumor, although in older patients this should arouse suspicion.

ACTH Syndrome, Ectopic↗
PubMed1999

CT appearance of the adrenal glands in adrenocorticotrophic hormone-dependent Cushing's syndrome.

OBJECTIVE: The purpose of this study was to describe the size and appearance of the adrenal glands on CT in patients with adrenocorticotrophic hormone (ACTH)-dependent Cushing's syndrome and to correlate gland dimensions with circulating cortisol and ACTH levels. MATERIALS AND METHODS: We retrospectively analyzed clinical, biochemical, and imaging data for 53 patients referred for CT of the adrenals as part of an investigation for ACTH-dependent Cushing's syndrome at our institution between 1988 and 1997. Two observers, who were unaware of the endocrine data, measured the body and limb widths of the adrenal glands using an electronic cursor. RESULTS: Of the 53 patients, 37 (70%) were shown to have enlarged adrenal glands on CT. The mean width of the adrenal limbs positively correlated with the circulating cortisol and ACTH levels. The adrenals were larger in patients with ectopic ACTH syndrome than in patients with Cushing's disease (p < .02). Ten patients (19%) had nodules that were 10 mm or greater in diameter. CONCLUSION: The adrenal glands were often enlarged in patients with ACTH-dependent Cushing's syndrome, and the enlargement could be quantified on CT. However, having normalsized adrenals (observed in 30% the patients in our study) did not preclude such a diagnosis. We found that adrenal limb width positively correlates with ACTH and cortisol levels.

ACTH Syndrome, Ectopic↗
PubMed1998

Orbital rhabdomyosarcoma--the radiological characteristics.

We reviewed computed tomography (CT) studies in 30 patients with histologically confirmed orbital rhabdomyosarcoma. There were 17 male and 13 female patients, mean age 8.8 years (median age 7 years, age range 1 month to 51 years). The tumour occupied the intra and extraconal compartments in 14 (47%) cases; it was solely extraconal in 11 (37%) and intraconal in five (16%). Within the orbit the upper inner quadrant was the most common site, 20 (67%) of the tumours lying in this region. More than one quadrant was involved in 16 (53%) cases. The epicentre of the tumour was in the eyelids of three (10%) patients. At presentation the mean size of the mass was 25 x 17 mm in long and short axis diameters, respectively. The tumours were of soft tissue density with moderately well defined margins and an irregular shape. They showed mild to moderate contrast enhancement. Calcification was seen in one case. Changes in the adjacent bone were seen in at least 12 (40%) patients. Intracranial extension was present in one (3%) patient and invasion of the paranasal sinuses was also seen in one (3%) patient. The intraorbital structures were displaced or encased by the tumour mass. The globe was displaced and distorted but not invaded by the tumour. Magnetic resonance imaging (MRI) studies were also reviewed in five patients. On T1-weighted images the tumour gave a similar signal to muscle but on T2-weighted images it gave a higher signal.

Adolescent↗
PubMed1997

The significance of hepatic lesions associated with small adrenocortical tumours in childhood.

Small adrenocortical tumours in children are rarely associated with hepatic pathology. We present two case reports of children with hepatic pathology associated with small adrenal tumours on computed tomography. One child had multiple granulomatous lesions due to toxocariasis and the other had focal nodular hyperplasia. Hepatic lesions seen in association with small adrenal tumours in childhood may represent coincidental rather than metastatic pathology.

Adenoma↗
PubMedDate not supplied

Routine computerized tomography scanning, groin ultrasound with or without fine needle aspiration cytology in the surgical management of primary squamous cell carcinoma of the vulva.

We set out to study whether computerized tomography (CT) scanning of the vulva and the groin and groin ultrasound scanning (USS) alone or with fine needle aspiration cytology (FNAC) (USS/FNAC) influenced or could influence the surgical management of primary squamous cell carcinoma of the vulva (SCCaV). Forty-four patients underwent surgery for primary SCCaV following radiologic imaging by one or more modalities. Patient details included the clinical assessment of the carcinoma, radiologic findings, the operation performed, and whether the decision regarding the type and extent of surgery for the vulval carcinoma and, in particular, for the groin node dissection was or could be influenced by the radiologic findings. The age range was 38-87 years, with a median of 74 years. A total of 75 groin dissections were performed. Twenty-five of the 44 patients (56.8%) did not have groin node metastasis, 14 had unilateral metastasis (31.8%), and 5 (11.4%) had bilateral metastasis. All cases with histologically proven nodal status were analyzed to compare the preoperative imaging status with the histology. The calculated sensitivity, specificity, negative predictive value, and positive predictive value for CT were 58%, 75%, 75%, and 58%, for USS alone-87%, 69%, 94%, and 48%, and for USS-guided FNAC-80%, 100%, 93%, and 100%, respectively. There was no patient in whom surgical planning for the vulval carcinoma or the groin nodes was or could be altered by the CT findings. The data do not support the routine use of CT scanning in patients with primary SCCaV, either in assessment of the primary vulval carcinoma or in detecting groin nodal metastases. For the groin nodes, USS/FNAC is superior to CT in assessing disease status. In contrast to CT, USS/FNAC may have a useful clinical role in the management of the groin nodes in vulval carcinoma.

Adult↗