Biomedical subjects

C F Hess

Publications and source records attributed to C F Hess.

76 records · Page 5Linked to original sources

PubMedDate not supplied

MR characteristics of prostatic carcinoma and benign prostatic hyperplasia at 1.5 T.

Sixty-one patients with histologically proven disorders of the prostate [prostatic carcinoma (PC), 41; benign prostatic hyperplasia (BPH), 9; PC and BPH, 11] underwent magnetic resonance imaging at 1.5 T. Using single [spin echo (SE) 400/30] and dual (SE 1,600/30, 90) SE sequences, multislice contiguous scans were obtained in transverse, sagittal, and coronal planes through the prostate. In 27 patients (PC 14, BPH 6, PC and BPH 7) multiecho sequences with eight echoes (SE 1,600/30, 60, 90, 120, 150, 180, 210, 240) were acquired and T2 images were calculated in the planes with best depiction of circumscribed prostatic pathology. In these patients the Bhattacharyya coefficient, a quantitative criterion for the discrimination between normal and pathological tissue, derived by means of mathematical decision theory, was applied. This analysis showed the best discrimination between PC and normal prostate with echo time (TE) 90 and 120 ms [error rate (ER) for confusing these tissues 20-30%]. There was no significant difference between the signal intensities of PC and BPH at any parameter setting, but PC could be discriminated from the compressed peripheral glandular regions that often accompany BPH [minimal ER (20-30%) at TE 90 and 120 ms]. This distinction is of clinical value, since PC usually arises in the periphery of the prostate. Calculated T2 images did not show advantages for the detection of PC.

Adenocarcinoma↗

PubMedDate not supplied

Dynamic sequential MR imaging of focal liver lesions: initial experience in 22 patients at 1.5 T.

The feasibility of dynamic sequential magnetic resonance (MR) imaging of focal hepatic lesions using Gd-diethylenetriamine pentaacetic acid (DTPA) was evaluated in this study. Three patients with hepatocellular carcinoma, 12 patients with metastases, and 7 patients with hemangiomas were studied with pre- and postcontrast multislice spin echo (SE) images using a repetition time of 500 ms and an echo time of 15 ms. The dynamic distribution phase of Gd-DTPA (0.1 mmol/kg) was investigated by using a sequential, transverse partial flip imaging sequence [fast low angle shot (FLASH)] before and after intravenous administration of Gd-DTPA. The lesion-liver contrast-to-noise ratio showed a great variability in patients with metastases and was significantly improved following administration of Gd-DTPA in patients with hemangiomas, two patients with hepatocellular carcinoma, and eight patients with metastases both on FLASH and SE images. Hemangiomas appeared darker than liver parenchyma on precontrast SE and FLASH images, increasingly enhanced over 5 min postinjection (pi) on FLASH images, and were still greatly enhanced at 10 min pi on SE images. During the dynamic sequential image acquisition the contrast enhancement of hemangiomas was significantly different from the enhancement observed in malignant lesions. The results of this study indicate the clinical potential of dynamic sequential imaging for the MR assessment of focal hepatic lesions.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

Hypoechoic lesions without halo in echogenic liver. A frequent sonographic dilemma.

Sonographic evaluation for the presence of hypoechoic hepatic lesions without halo was carried out in 365 consecutive patients with echogenic livers. In 115 patients (31%) such lesions could be demonstrated. Computed tomography of the liver was performed in 52 of these patients, a long term sonographic follow-up in 76, and a biopsy in 3 cases. In 103 patients the hypoechoic lesions were due to sonographic pseudolesions (PL's), probably representing normal liver tissue in otherwise diffusely fatty infiltrated livers. The PL's showed characteristic sonographic appearances such as a missing mass effect, a 'landscape'-like configuration with angulated margins and slender extensions of hypoechoic tissue. The PL's were located below the capsule, near the gallbladder (41%), and ventral to the portal vein (37%). In 75 per cent they occurred in a liver with considerably increased echogenicity. In 12 patients hypoechoic lesions were caused by circumscribed malignant or infectious involvement of the liver. They could be discriminated from PL's by their mass-like appearance in 8 subjects. In 4 of these 12 cases the foci were of PL-typical appearance, but not of PL-typical location. In the light of these results and of recently published reports a rational diagnostic approach to hypoechoic lesions without halo in echogenic livers varies, depending on such factors as known primary malignancy or site of the lesion.

Diagnosis, Differential↗

PubMedDate not supplied

Adjuvant radiotherapy in the treatment of breast cancer.

Recent studies on the impact of adjuvant radiotherapy on local control, survival and quality of life in patients with breast cancer have been evaluated. Following these studies, breast conserving surgery with subsequent radiation therapy is the standard treatment for early breast cancer. In advanced disease, radiation is indicated for patients with T3- or T4 and/or with four or more positive lymph nodes. In general, radiotherapy leads to a 2-4 fold reduction of local relapse. In addition, there is considerable evidence that radiotherapy is associated with a higher overall survival. In elderly women postoperative radiotherapy should not be withheld. An extensive intraductal component (EIC) or multicentric disease can be compatible with breast conserving therapy if surgery has been completed. Self assessment of patients rated the cosmetic results of breast conserving therapy higher than mastectomy and breast reconstruction.

Breast Neoplasms↗