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Ann T Sweeney

Publications and source records attributed to Ann T Sweeney.

10 recordsLinked to original sources
PubMed2006

Comparison of the effects of a new conjugated oral estrogen, estradiol-3beta-glucoside, with oral micronized 17beta-estradiol in postmenopausal women.

The objective of this article is to evaluate the pharmacokinetics of serum estrone and estradiol levels in women who were taking either 17beta-estradiol-3beta-glucoside (E(2)-3beta-glucoside) or 17beta-estradiol (E(2)) daily and to examine the effects of E(2)-3beta-glucoside and E(2) on postmenopausal symptoms, gonadotropins, hepatic metabolism, and coagulation factors. Healthy postmenopausal women on estrogen who had undergone a hysterectomy were recruited. Subjects were randomly assigned to receive equivalent doses of either E(2)-3beta-glucoside or micronized E(2) for 28 days. Pharmacokinetic studies of estrone and estradiol were performed on days 1, 2, 28, and 29. Gonadotropin levels and Kupperman Index (KI) scores were determined at baseline and on treatment day 28. Mean serum estradiol and estrone concentrations in those taking E(2)-3beta-glucoside were comparable with those taking E(2). Mean baseline follicle stimulating hormone (FSH) levels were 84 +/- 27 mIU/mL and 71 +/- 24 mIU/mL in the E(2)-3beta-glucoside and E(2) groups, respectively, with significant decreases (P < 0.01) of 54 +/- 21 mIU/mL and 38 +/-18 mIU/mL, respectively, by treatment day 28. Baseline KI scores in the E(2)-3beta-glucoside group were 10 +/- 6 compared with 5 +/- 4 on treatment day 28, which is equivalent to a 50% reduction in menopausal symptoms (P = 0.003). The change in KI scores in the E(2) group was not statistically significant. Total serum estradiol and estrone levels in women taking E(2)-3beta-glucoside are comparable with those in women taking E(2). E(2)-3beta-glucoside reduces serum gonadotropin levels to the premenopausal range and is effective at reducing postmenopausal symptoms. E(2)-3beta-glucoside is a novel synthetic estrogen that is well tolerated and has promise as a hormone replacement therapy.

Administration, Oral↗
PubMed2006

Adrenocortical carcinoma: contrast washout characteristics on CT.

OBJECTIVE: The purpose of this study was to characterize pathologically proven adrenocortical carcinoma by examination of washout attenuation characteristics on contrast-enhanced CT images. CONCLUSION: Adrenocortical carcinoma has relative contrast retention on delayed contrast-enhanced CT. All tumors in this series had a relative percentage washout less than 40%, a finding consistent with malignant disease.

Adrenal Cortex Neoplasms↗
PubMed2005

Distinguishing benign from malignant adrenal masses: multi-detector row CT protocol with 10-minute delay.

PURPOSE: To retrospectively evaluate the accuracy of precontrast attenuation, relative percentage washout (RPW), and absolute percentage washout (APW) in distinguishing benign from malignant adrenal masses at multi-detector row computed tomography (CT). MATERIALS AND METHODS: This HIPAA-compliant retrospective study had institutional review board approval; the need for informed consent was waived. One hundred twenty-two adrenal masses were evaluated in 99 patients (51 men, 48 women; age range, 37-86 years) who had undergone CT performed according to the study protocol and who either were given a pathologic diagnosis or underwent follow-up imaging. Unenhanced images were obtained before administration of 120 mL of an intravenous contrast agent with a 75-second scan delay. Delayed images were obtained after 10 minutes. RPW and APW were computed. Receiver operating characteristic (ROC) analysis was performed to compare mean attenuation and both RPW and APW. Analysis was first performed with the exclusion of pheochromocytomas, myelolipomas, and cysts. Precontrast attenuation criteria specific for benignity or malignancy were determined, and ROC analysis of results for the entire nonpheochromocytoma group was then performed. RESULTS: By using an RPW of 37.5% and excluding cysts and myelolipomas, all malignant lesions were detected with a sensitivity of 100% (17 of 17 lesions) and a specificity of 95% (90 of 95 lesions). Area under the binomial ROC curve (A(z)) values were 0.912, 0.985, and 0.892 for precontrast attenuation, RPW, and APW, respectively. Precontrast attenuation of less than 0 or more than 43 HU indicated benign and malignant entities, respectively. Incorporation of these criteria into the APW analysis yielded a sensitivity of 100% (17 of 17 lesions) and a specificity of 98% (93 of 95 lesions) for a threshold washout value of 52.0%. This attenuation-corrected APW generated the greatest A(z) value (ie, 0.988). Combining all the information available from the protocol yielded a sensitivity of 100% (17 of 17 lesions) and a specificity of 98% (98 of 100 lesions) for differentiating benign from malignant masses. CONCLUSION: Precontrast attenuation of less than 0 HU supercedes the washout profile in the evaluation of an individual adrenal mass. Noncalcified, nonhemorrhagic adrenal lesions with precontrast attenuation of more than 43 HU should be considered suspicious for malignancy.

Adrenal Gland Diseases↗
PubMed2004

Pheochromocytoma: an imaging chameleon.

Pheochromocytomas are rare catecholamine-secreting tumors with many clinical and imaging manifestations. They may produce overwhelming cardiovascular crises if the diagnosis is not made or if appropriate treatment is delayed. It is thus important to recognize both their characteristic and atypical imaging appearances. Pheochromocytomas are encountered, sometimes unexpectedly, across a range of imaging modalities. They are characteristically solid, hypervascular masses with high signal intensity on T2-weighted magnetic resonance (MR) images. A wide spectrum of imaging appearances is seen, however, and pheochromocytomas may mimic other adrenal lesions, both benign and malignant. They may be dark on T2-weighted MR images, in contrast to their more classic bright T2-weighted appearance. Other atypical features include fatty, hemorrhagic, cystic, and calcific changes. Pheochromocytomas may contain sufficient fat to be mistaken for an adenoma at computed tomography (CT) or MR imaging. They may also demonstrate rapid contrast material washout and be mistaken for an adenoma owing to their deenhancement profile; however, their washout pattern can be inconsistent. The appearance of pheochromocytomas at radionuclide imaging is also unpredictable. These characteristics at CT, MR imaging, and scintigraphy pose diagnostic challenges, since they allow pheochromocytomas to mimic many other adrenal masses. Pheochromocytoma is an important, often clinically occult neoplasm with devastating consequences if overlooked. Radiologists must be aware of the various forms that pheochromocytomas can assume at imaging.

Adrenal Gland Neoplasms↗
PubMed2003

Low-density pheochromocytoma on CT: a mimicker of adrenal adenoma.

OBJECTIVE: Attenuation values on CT of less than 10 H are considered characteristic of adrenal adenomas. Adrenal pheochromocytomas can infrequently contain fat that could result in low attenuation on CT. The purpose of our study was to determine if pheochromocytomas could be confused with adenomas by virtue of their attenuation values on unenhanced CT. MATERIALS AND METHODS: CT attenuation and size of nine adrenal nodules producing pheochromocytoma syndrome were measured on unenhanced CT in nine patients. For five patients who received IV contrast material, washout profiles were also calculated. RESULTS: Two of the nine patients had adrenal lesions with attenuation values of less than 10 H; one had a pheochromocytoma with an attentuation of 9.0 H, and the other had a medullary hyperplasia with an attenuation of 1.8 H. These two nodules showed evidence of microscopic fat at histologic examination. No macroscopic fat was seen on the CT scans. The remaining seven patients had lesions with attenuation values exceeding 10 H (mean value, 25.6 H; range, 1.8-41 H). Mean diameter of the nine tumors (including the hyperplastic nodule) was 3.2 cm (range, 0.8-6.7 cm; SD, +/- 2.3 cm). The two low-attenuation lesions also mimicked adenomas by displaying more than 60% contrast washout on 10-min-delayed contrast-enhanced scans, unlike the other three pheochromocytomas for which we had washout data. CONCLUSION: On CT, pheochromocytomas may have attenuation values less than 10 H and also may display more than 60% washout of contrast agents on delayed scanning. Adrenal pheochromocytomas should be included with adenomas in the differential diagnosis both for masses with low attenuation on unenhanced CT and for lesions exhibiting a high percentage of contrast washout.

Adenoma↗
PubMed2002

Bone mineral density assessment: comparison of dual-energy X-ray absorptiometry measurements at the calcaneus, spine, and hip.

It is widely accepted that bone mineral density (BMD) measurements obtained by dual-energy X-ray absorptiometry (DXA) at the spine, hip, and calcaneus predict fracture risk. Few published studies to date have examined the relationship between pDXA measurements at the calcaneus to those at the hip and spine. It has been demonstrated that T-score-based criteria cannot be universally applied to all skeletal sites and measurement technologies. Our goal was to define the calcaneal T-score threshold equivalent to low bone mass at the hip or spine. A total of 119 female patients between the ages of 33 and 76 yr of age were recruited at Boston University Medical Center for bone densitometry screening. Bone density measurements were obtained at the calcaneus using the portable Norland Apollo Densitometer (Norland Medical Systems, Fort Atkinson, WI) and at the hip and spine using the Norland Eclipse densitometer. By defining a pDXA T-score < or =-1 as a positive test and DXA scores < or =-1 as the presence of low bone mass, we obtained a specificity of 100% and a sensitivity of 73% (positive predictive value 100% and negative predictive value 80%) in detecting low bone mass at the femoral neck in women over age 65 yr. In women between 40 and 65 yr of age, we obtained a sensitivity of 50% and a specificity of 93% (positive predictive value 93% and negative predictive value 50%) in detecting low bone mass at the femoral neck. In women less than 40 yr of age, we obtained a sensitivity of 13% and a specificity of 100% (positive predictive value 100% and negative predictive value 75%) in detecting low bone mass at the femoral neck. From receiver operating characteristic curves, a calcaneal T-score < or =0.0 detects those with a T-score < or =-1 at the femoral neck and lumbar spine with 100% and 85% sensitivity, respectively. Peripheral DXA of the calcaneus is a sensitive and specific test to diagnose low bone mass in women over 65 yr of age. In women under 65 yr of age, this modality, though not as sensitive, is specific in detecting low bone mass. We conclude that a pDXA calcaneal T-score < or =0 is highly sensitive in predicting osteopenia and osteoporosis at the femoral neck and lumbar spine.

Absorptiometry, Photon↗
PubMedDate not supplied

State of the art in adrenal imaging.

The purposes of this article were to outline the current state of adrenal imaging, to highlight new developments, and to review the current radiologic advances that provide improved functional and structural information about adrenal disorders.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Pituitary apoplexy precipitating diabetes insipidus.

OBJECTIVE: To describe a case of pituitary apoplexy complicated by diabetes insipidus and to review management of patients with pituitary apoplexy and water excretion disturbances associated with transsphenoidal surgery. METHODS: We describe clinical, laboratory, and radiologic findings in a patient with pituitary apoplexy and central diabetes insipidus. RESULTS: A 74-year-old woman presented with severe headache and sudden loss of vision for 12 hours, accompanied by thirst and frequent urination. Visual field examination demonstrated bitemporal hemianopsia. Her laboratory findings were significant for a serum sodium level of 152 mEq/L and urine specific gravity of <1.005. A magnetic resonance imaging scan of her pituitary gland identified a 3.5-cm suprasellar mass compressing the optic chiasm. She subsequently underwent transsphenoidal pituitary surgery with subtotal resection of this mass. Microscopic evaluation of tumor tissue revealed a pituitary adenoma with evidence of recent infarct and hemorrhage. Her clinical and biochemical course was consistent with the triphasic response that may occur after pituitary surgery related to damage to the hypothalamus and supraopticohypophyseal tract. CONCLUSION: Pituitary apoplexy may be rarely associated with diabetes insipidus.

Adenoma↗
PubMedDate not supplied

A malignant aldosteronoma.

OBJECTIVE: To describe a case of primary aldosteronism due to an adrenocortical carcinoma (ACC) and highlight the need for thorough long-term follow-up. METHODS: We present the clinical, laboratory, radiologic, and pathologic findings in a patient with ACC and review the related literature. RESULTS: A 52-year-old woman with a history of hypertension and hypokalemia was referred for evaluation of a 6-cm adrenal mass. Her biochemical studies revealed a serum aldosterone-to-renin ratio of 52 without evidence of cortisol, catecholamine, or androgen excess. She underwent surgical resection of this mass, and histologic analysis showed a focally brisk mitotic rate but no evidence of capsular or vascular invasion. In light of these findings, the biologic nature of the tumor was difficult to predict. Thus, it was thought to be an adrenocortical neoplasm. The patient underwent follow-up clinically, biochemically, and with interval computed tomography. Nine years later, hypertension and hypokalemia redeveloped, and she was found to have metastatic ACC. CONCLUSION: ACC can generally be reliably diagnosed; however, in some cases, the true biologic behavior is difficult to predict. We emphasize the importance of careful clinical, biochemical, and radiologic surveillance in these difficult cases because surgical resection provides the best opportunity for cure in patients with adrenal cancer.

Adrenal Cortex Neoplasms↗