Evaluation of surgical outcomes and gallbladder characteristics in patients with biliary dyskinesia.

Introduction: This study was designed to compare symptomatic outcomes following cholecystectomy in patients with biliary dyskinesia.

Materials And Methods: From 1999 to 2006 at New York University Medical Center, 197 adults underwent hepatobiliary scintigraphy with cholecystokinin administration to evaluate gallbladder ejection fraction (GBEF). Biliary dyskinesia was demonstrated in 120 patients based on decreased GBEF of View Article and Find Full Text PDF

Improving specificity of breast MRI using prone PET and fused MRI and PET 3D volume datasets.

Unlabelled: MRI is a sensitive method for detecting invasive breast cancer, but it lacks specificity. To examine the effect of combining PET with MRI on breast lesion characterization, a prototype positioning device was fabricated to allow PET scans to be acquired in the same position as MRI scans--that is, prone.

Methods: To test the hypothesis that fusion of (18)F-FDG PET and MRI scans improves detection of breast cancer, 23 patients with suspected recurrent or new breast cancer underwent a routine whole-body PET scan, a prone PET scan of the chest, and a routine breast MRI scan.

What causes diminished corticomedullary differentiation in renal insufficiency?

Purpose: To investigate whether the loss of corticomedullary differentiation (CMD) on T1-weighted MR images due to renal insufficiency can be attributed to changes in T1 values of the cortex, medulla, or both.

Materials And Methods: Study subjects included 10 patients (serum creatinine range 0.6-3.

Prone mammoPET acquisition improves the ability to fuse MRI and PET breast scans.

Purpose: This study compared prone acquisition of PET scans with traditional supine acquisition to improve fusion of PET scans with MRI scans and improve evaluation of enhancing breast lesions detected on MRI.

Materials And Methods: MRI breast scans are acquired in the prone position using a breast coil to allow the breasts to hang pendant. An apparatus was fabricated to allow prone acquisition of PET scans.

Renal function measurements from MR renography and a simplified multicompartmental model.

The purpose of this study was to determine the accuracy and sources of error in estimating single-kidney glomerular filtration rate (GFR) derived from low-dose gadolinium-enhanced T1-weighted MR renography. To analyze imaging data, MR signal intensity curves were converted to concentration vs. time curves, and a three-compartment, six-parameter model of the vascular-nephron system was used to analyze measured aortic, cortical, and medullary enhancement curves.

Enhancing the utility of prostascint SPECT scans for patient management.

This project investigated reducing the artifact content of In-ill ProstaScint SPECT scans for use in treatment planning and management. Forty-one patients who had undergone CT or MRI scans and simultaneous Tc-99m RBC/In-111 ProstaScint SPECT scans were included. SPECT volume sets, reconstructed using Ordered Set-Expectation Maximum (OS-EM) were compared against those reconstructed with standard Filtered Back projection (FBP).

Diffuse FDG shoulder uptake on PET is associated with clinical findings of osteoarthritis.

Objective: Our objective was to examine the degree and pattern of (18)F-FDG uptake within the shoulder as a potential marker of joint inflammation or injury.

Subjects And Methods: Twenty-four patients undergoing (18)F-FDG PET for clinical oncologic assessment completed questionnaires regarding history of shoulder disease, trauma, pain, and/or functional impairment. Thorough physical examination of the shoulder was performed.

Fluorodeoxyglucose (FDG) uptake in pulmonary rheumatoid nodules.

A 60-year-old female patient with a 5-year history of rheumatoid arthritis (RA) presented with pulmonary nodules on chest radiograph and computed tomography (CT) scan. The positron emission tomography (PET) demonstrated mild fluorodeoxyglucose (FDG) uptake in these nodules, which is characteristic of benign lesions. Histopathological correlation confirmed this.

FDG uptake in tumor thrombus in inferior vena cava from rectal cancer on positron emission tomography.

A 74-year-old woman with a history of rectal carcinoma underwent whole body combined positron emission tomography/computed tomography (PET/CT) scanning for staging. Diffuse intense FDG uptake was seen in the distended infrarenal inferior vena cava (IVC) extending to the bilateral common iliac and left external as well as internal iliac veins. Heterogeneous hyperdense material was seen on the corresponding CT scan, suggesting tumor thrombus.

Lymphoscintigraphy: defining a clinical role.

Radionuclide lymphoscintigraphy is a useful technique for differentiating lymphedema from other causes of swelling, and may sometimes be useful for delineating collateral lymphatics, the level of obstruction, and the presence of lymphoceles or abnormal collections of lymphatic vessels, if they communicate sufficiently with normal lymphatic vessels. Standardization of technique is important to provide better intrapatient and even interpatient comparison. Symmetry, numbers, and locations of lymphatic vessels, lymph nodes, abnormal collections, and dermal collaterals are helpful in the qualitative assessment of lymphoscintigraphy.

Spectrum of thymic uptake at 18F-FDG PET.

Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has emerged as a strong diagnostic tool for the diagnosis and staging of neoplasms. Uptake in the thymus at (18)F-FDG PET complicates the assessment of mediastinal involvement by tumor in children and young adults. Increased thymic (18)F-FDG uptake may represent normal physiologic uptake but may also indicate the presence of thymic hyperplasia, lymphomatous infiltration, primary thymic neoplasm, or metastatic disease.

Procedure for unmasking localization information from ProstaScint scans for prostate radiation therapy treatment planning.

Purpose: To demonstrate a method to extract the meaningful biologic information from (111)In-radiolabeled capromab pendetide (ProstaScint) SPECT scans for use in radiation therapy treatment planning by removing that component of the (111)In SPECT images associated with normal structures.

Methods And Materials: We examined 20 of more than 80 patients who underwent simultaneous (99m)Tc/(111)In SPECT scans, which were subsequently registered to the corresponding CT/MRI scans.A thresholding algorithm was used to identify (99m)Tc uptake associated with blood vessels and CT electron density associated with bone marrow.

Impact of fusion of indium-111 capromab pendetide volume data sets with those from MRI or CT in patients with recurrent prostate cancer.

Objective: Our goal was to evaluate the impact of image fusion on the interpretation of indium-111 Prosta-Scint SPECT scans.

Materials And Methods: Sixty-seven consecutive patients referred for rising prostate-specific antigen (PSA) levels after initial therapy for primary prostate cancer underwent SPECT 96 hr after infusion of (111)In Prosta-Scint, with simultaneous technetium-99m blood pool imaging. Volume data sets from the SPECT scans were then fused with those from CT and MR images of the pelvis using a 3D landmark-based warping program.

Limitations of technetium 99m sestamibi scintigraphic localization for primary hyperparathyroidism associated with multiglandular disease.

Successful surgical treatment of primary hyperparathyroidism requires the localization and excision of the parathyroid tissue responsible for excessive parathyroid hormone secretion while ensuring that the patient will have sufficient endogenous parathyroid hormone production to maintain eucalcemia. In selecting patients with primary hyperparathyroidism for unilateral parathyroidectomy the surgeon should be able to diagnose multiglandular disease either preoperatively or intraoperatively. We performed a retrospective review of 123 patients who underwent surgical treatment for primary hyperparathyroidism to determine the potential feasibility of selecting patients for minimally invasive surgery based on preoperative imaging studies.

Dynamic three-dimensional MR renography for the measurement of single kidney function: initial experience.

A three-dimensional magnetic resonance (MR) renographic method to measure single kidney glomerular filtration rate (GFR) and split renal function was developed that is based on renal signal intensity measurements during 2-3 minutes after intravenous injection of a low dose (2 mL or 0.01 mmol/kg) of gadopentetate dimeglumine. In nine subjects, single kidney MR GFR indices correlated well with technetium 99m (99mTc) diethylenetriaminepentaacetic acid (DTPA) clearance (r = 0.

Stratifying differences on ictal/interictal subtraction SPECT images.

Purpose: Subtraction of interictal from ictal single-photon emission computed tomography (SPECT) yields numerous foci that encompass a range of pixel values scattered in the brain. This preliminary study evaluated the significance of this range of values.

Methods: Subtraction images were obtained by registering, normalizing, and subtracting interictal from ictal SPECT for 13 patients.

Evaluation of a segmentation procedure to delineate organs for use in construction of a radiation therapy planning atlas.

Objectives: This paper evaluates a semi-automatic segmentation procedure to enhance utilizing atlas based treatment plans. For this application, it is crucial to provide a collection of 'reference' organs, restorable from the atlas so that they closely match those of the current patient. To enable assembling representative organs, we developed a semi-automatic procedure using an active contour method.

Tumor localization and image registration of F-18 FDG coincidence detection scans with computed tomographic scans.

Purpose: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management.

Methods: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice.