Ultrasound-guided fine-needle aspiration biopsy of thyroid masses.

The purpose of this study was to determine the impact of ultrasound-guided fine-needle aspiration biopsy (USFNA) in the cytological diagnosis of nodular thyroid disease. It remains unclear exactly what role USFNA should play in the cytological diagnosis of nodular thyroid disease. All patients who underwent fine-needle aspiration (FNA) for nodular thyroid disease at Stanford University Medical Center from 1991 to 1996 were included in the study.

Isoflurane alters shivering patterns and reduces maximum shivering intensity.

Background: Shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase with further core hypothermia), and maximum response intensity. Isoflurane produces a clonic muscular activity that is not a component of normal shivering. To the extent that clonic activity is superimposed on normal thermoregulatory shivering, the gain of shivering might be increased during isoflurane anesthesia.

Epidural anesthesia reduces the gain and maximum intensity of shivering.

Background: Shivering can be characterized by its threshold (triggering core temperature), gain (incremental intensity increase), and maximum intensity. The gain of shivering might be preserved during epidural or spinal anesthesia if control mechanisms compensate for lower-body paralysis by augmenting the activity of upper-body muscles. Conversely, gain will be reduced approximately by half if the thermoregulatory system fails to compensate.

Dual-phase helical CT of locally invasive pancreatic adenocarcinoma.

Dual-phase helical CT permits imaging of the pancreas and the peripancreatic structures in the arterial dominant and portal venous phases of enhancement, providing information crucial in the assessment of the local extent of pancreatic adenocarcinoma. This essay reviews the dual-phase helical CT findings of local extension that preclude potentially curative surgery, including vascular involvement, ligamentous or mesenteric invasion, extension of the tumor to involve the stomach or duodenum, and invasion of adjacent solid organs.

Dexmedetomidine does not alter the sweating threshold, but comparably and linearly decreases the vasoconstriction and shivering thresholds.

Background: Clonidine decreases the vasoconstriction and shivering thresholds. It thus seems likely that the alpha2 agonist dexmedetomidine will also impair control of body temperature. Accordingly, the authors evaluated the dose-dependent effects of dexmedetomidine on the sweating, vasoconstriction, and shivering thresholds.

Power Doppler imaging in preoperative planning and postoperative monitoring of muscle flaps.

Purpose: We assessed the utility of power Doppler imaging (PDI) in preoperative planning and postoperative evaluation of microvascular tissue transfers.

Methods: Twenty-five PDI studies were performed on 23 patients using a 5-10-MHz linear-array transducer. Thirteen patients were assessed preoperatively for patency of the desired donor vessel; 8 of them had surgical scars overlying the desired vascular territory.

Preliminary experience with power Doppler imaging of solid breast masses.

Objective: The purpose of our study was to assess the potential of power Doppler imaging (PDI) to differentiate benign from malignant solid breast masses.

Materials And Methods: Sixty-nine biopsy-proven solid breast masses were evaluated with PDI using 7- to 10-MHz transducers optimized for low-volume flow sensitivity. The extent of flow on PDI was estimated as a percentage of the lesion area on multiple longitudinal and transverse static sonographic images.

Reduced pregnancy rates following the transfer of human embryos frozen or thawed in culture media supplemented with normal serum albumin.

Over a 26 month period 17% of couples having treatment in our clinical programmes selected a commercially available protein (normal serum albumin, NSA) prepared from pooled human sera instead of using their own serum as a supplement for their embryo culture media. In a retrospective analysis of >2000 gonadotrophin-stimulated cycles and 1000 cycles where frozen/thawed embryos were transferred, fertilization, embryo quality and pregnancy rates following in-vitro fertilization (IVF), gamete intra-Fallopian transfer (GIFT) or intracytoplasmic sperm injection (ICSI) were unaffected by the type of protein used to supplement the culture medium. When embryos were thawed in medium containing NSA, both pregnancy (PR) and implantation rates (IR) were significantly lower (P <0.

Acalculous cholecystitis in patients undergoing bone marrow transplantation.

Objective: To evaluate factors associated with acalculous cholecystitis in patients undergoing bone marrow transplantation and the role of repeat ultrasound examinations.

Design: Retrospective study.

Setting: University hospital, United States.

p53, c-erbB-2 and nm23 expression have no prognostic significance in primary pulmonary adenocarcinoma.

Objective: We analysed nm23, c-erbB-2 and p53 protein expression in lung adenocarcinoma in relation to clinicopathological status and patient survival, to elucidate any potential prognostic value. Published reports suggest that high p53 and c-erbB-2 protein expression and loss of nm23 protein expression are associated with poor prognosis.

Methods: A total of 162 pulmonary adenocarcinomas resected between 1980 and 1991 were stained using monoclonal antibodies to nm23 (NCL-nm23), c-erbB-2 (NCL-CB11) and p53 (DAKO Do7).

Spontaneous intramural small bowel haemorrhage: importance of non-contrast CT.

The purpose of this study was to evaluate the abdominal CT findings in patients with spontaneous intramural small bowel haemorrhage. We retrospectively reviewed the abdominal CT scans of six patients with known intramural small bowel haemorrhage. All of the patients had an underlying coagulopathy.

Do arterial phase helical CT images improve detection or characterization of colorectal liver metastases?

Our goal was to determine if arterial phase images from dual phase helical CT improve either the detection or the characterization of hepatic metastases in patients with colorectal carcinoma. Sixty-two patients with known colorectal cancer underwent 65 dual phase helical CT examinations to evaluate for possible liver metastases. Three blinded reviewers independently evaluated the portal venous phase images alone to determine if hepatic metastases were present or absent.

Renal hypoperfusion: value of power Doppler imaging.

The improved depiction of renal parenchymal vascularity with power Doppler imaging facilitates the sonographic detection of hypovascular lesions such as pyelonephritis, renal abscesses, and infarction. However, the finding of diminished or absent lobar perfusion may be present in all of these entities; thus, the abnormalities shown on power Doppler imaging are often nonspecific. Clinical and laboratory data are often essential to establish the correct diagnoses.

The infraconal compartment: a multidirectional pathway for spread of disease between the extraperitoneal abdomen and pelvis.

Purpose: The space below the kidneys where the anterior and posterior pararenal spaces converge has been defined only vaguley in the past. We describe observations on clinical CT cases and studies on cadavers that lead to a refinement in the terminology for this extraperitoneal compartment.

Method: Abdominal/pelvic CT scans from 18 patients and the scans of 2 cadavers injected in the femoral region with iodinated contrast material were reviewed concerning the location and distribution of fluid or gas collections relative to the renal fascial enclosure.

Power versus color Doppler sonography of the normal cystic artery: implications for patients with acute cholecystitis.

Objective: The purposes of this investigation were to compare prospectively the pattern and extent of cystic artery flow revealed by power Doppler sonography and color Doppler sonography in patients with normal gallbladders and to analyze the potential implications of these findings for power Doppler sonography in diagnosing acute cholecystitis.

Subjects And Methods: The cystic arteries of 142 patients (79 women and 63 men) with normal gallbladders were imaged with both power Doppler sonography and color Doppler sonography using 5-MHz transducers and settings optimized to reveal low-volume flow. The presence or absence of cystic artery flow and the anatomic extent of its visualization were recorded for each patient.

Unenhanced helical CT for suspected acute appendicitis.

Objective: The purpose of this study was to determine the diagnostic accuracy of unenhanced helical CT scans in patients with a suspected acute appendicitis.

Subjects And Methods: Over a 20-month period, 109 adult patients with suspected acute appendicitis were referred by the emergency department for an unenhanced helical CT scan. Each scan was obtained in a single breath-hold from the T12 vertebral body to the public symphysis using a 5-mm collimation and a pitch of 1.

Perspective volume rendering of CT and MR images: applications for endoscopic imaging.

Purpose: To use perspective volume rendering (PVR) of computed tomographic (CT) and magnetic resonance (MR) imaging data sets to simulate endoscopic views of human organ systems.

Materials And Methods: Perspective views of helical CT and MR images were reconstructed from the data, and tissues were classified by assigning color and opacity based on their CT attenuation or MR signal intensity. "Flight paths" were constructed through anatomic regions by defining key views along a spline path.

Diagnosis of pancreatic injury after blunt abdominal trauma.

Expeditious diagnosis and treatment of pancreatic injury continues to elude the trauma surgeon and radiologist. Missed or underestimated pancreatic injury is responsible for a high level of morbidity and mortality after blunt or penetrating trauma. Unfortunately, inappropriate therapy can lead to devastating consequences such as severe endocrine or exocrine insufficiency.

Normal variations in the lateral contour of the head and neck of the pancreas mimicking neoplasm: evaluation with dual-phase helical CT.

Objective: The purpose of this study was to analyze variations in the lateral contour of the head and neck of the pancreas that can mimic pancreatic masses on CT imaging.

Materials And Methods: We retrospectively reviewed dual-phase helical CT examinations of 119 patients who had no clinical or CT evidence of pancreatic disease. Contour variations of the head and neck of the pancreas were analyzed and were classified according to their anatomic orientation.

Screening for deep venous thrombosis in asymptomatic postoperative orthopedic patients using color Doppler sonography: analysis of prevalence and risk factors.

Objective: The purpose of our study was to assess the prevalence and risk factors for sonographically detectable lower extremity deep venous thrombosis (DVT) in asymptomatic patients following major orthopedic surgery.

Subjects And Methods: We performed color Doppler sonography of the lower extremities in 474 asymptomatic patients following major hip or knee surgery. We determined the prevalence of lower extremity DVT and used stepwise logistic regression to identify factors predictive of DVT.