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C M Tempany

Publications and source records attributed to C M Tempany.

60 records · Page 4Linked to original sources

MRI of the renal veins: assessment of nonneoplastic venous thrombosis.

Nonneoplastic renal vein thrombosis (RVT) is a clinical dilemma that poses a problem both from a clinical and diagnostic imaging perspective. An accurate noninvasive study to diagnose nonneoplastic RVT would be desirable. Magnetic resonance flow imaging is a noninvasive method of assessing vascular patency and depiction of thrombus. Its use for detection of nonneoplastic RVT is reviewed and our experience illustrated. We reviewed retrospectively the MRI studies in 41 patients evaluated for RVT and correlated them with other imaging studies where possible. Twenty patients had either ultrasound or venography. There were no correlative imaging studies done in 21 patients, 19 of whom had normal MRI, with normal clinical follow-up. In others there was good agreement between MRI and ultrasound in 16 of 19 cases. There were five patients with renal venography, of which the MRI agreed with the results in 3 of 5. Magnetic resonance imaging offers a noninvasive approach to the difficult diagnostic dilemma of RVT.

Adolescent↗

Accuracy of in-vivo assessment of prostatic volume by MRI and transrectal ultrasonography.

More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume.

Adenocarcinoma↗

Effect of slice acquisition direction on image quality in thoracic MRI.

OBJECTIVE: We tested the basic observation that imaging the heart and pericardium in systole improves image quality compared with that in diastole. MATERIALS AND METHODS: Twenty consecutive patients and two volunteers underwent sequential ECG-gated short TE transaxial prospective multislice SE MRI with both caudocranially and craniocaudally directed slice prescriptions, keeping other imaging parameters constant. Images of the heart and pericardium were obtained in systole and diastole and examined by three independent reviewers for image quality. RESULTS: In the lower mediastinum, cardiac structures and the pericardium were better seen in 49 of 57 individual evaluations when imaged in systole, 15 of which were judged markedly better. Vascular structures and the pericardium in the upper mediastinum were imaged equally well with both prescriptions. CONCLUSION: The findings suggest that in systole, the more mobile heart can maintain a more consistent shape during the acquisition of successive phase-encoding steps and preserve luminal flow void, factors critical to optimizing image quality in the transaxial plane.

Adolescent↗

Spiral CT in the evaluation of flank pain: overall accuracy and feature analysis.

PURPOSE: Our goal was to assess test reliability and identify those features that have the strongest positive and negative predictive values in the diagnosis of renal colic using spiral CT. METHOD: Fifty non-contrast-enhanced CT scans (5 mm slice thickness) obtained in patients presenting with flank pain were reviewed by three radiologists blinded to the final diagnoses. The sensitivity, specificity, and positive and negative predictive values for nine pertinent findings were determined as compared to clinical follow-up. RESULTS: Twenty-nine cases had findings of ureteral obstruction. Findings with the strongest positive predictive values (> 0.90) were ureteral stone, hydronephrosis, hydroureter, periureteral stranding, and ureterovesical junction edema. Findings with the strongest negative predictive values (> 0.89) were absence of hydronephrosis and hydroureter. The areas under the receiver operating curves for Readers 1, 2, and 3 were 0.970 +/- 0.030, 0.942 +/- 0.036, and 0.982 +/- 0.020. CONCLUSION: Absence of hydroureter and hydronephrosis on spiral CT images should prompt a search for a diagnosis other than an obstructing ureteral stone.

Adult↗

MR detection of breast implant rupture.

Breast implant rupture can be difficult to diagnosis. Various modalities including direct clinical palpation, ultrasound, CT, and mammography have been used to evaluate for the presence of prosthesis rupture. We report a case in which the presence of breast implant rupture was determined using MR with characterization of the inflammatory reaction in the soft tissues around the implant. The absence of ionizing radiation with MR makes it especially well suited for evaluating implant rupture in younger patients in whom breast irradiation should be minimized.

Breast↗