Thomas Rettenbacher

Colonic diverticulitis: diagnostic value and appearance of inflamed diverticula–sonographic evaluation

Abstract. Acute bowel inflammation frequently originates from thin-walled diverticula of the colon. Not the presence of diverticula, but the demonstration of an inflamed diverticulum, is diagnostic of diverticulitis in cases of bowel wall thickening and pericolic inflammation. The aim of this study was to investigate the sonographic appearance and detectability of inflamed diverticula. One hundred seventy-five consecutive patients with clinically suspected diverticulitis underwent sonographic examination. Outpouchings from the colonic wall centred in the pericolic inflammation were considered inflamed diverticula. Depending on the sonographic appearance they were divided into four groups: hypoechoic; predominantly hyperechoic; hyperechoic with surrounding hypoechoic rim; and hyperechoic with acoustic shadowing. Sonography showed inflamed diverticula in 79 (77%) of 102 patients with diverticulitis. Inflamed diverticula were hypoechoic in 37%, predominantly hyperechoic in 4%, hyperechoic with surrounding hypoechoic rim in 41% and hyperechoic with acoustic shadowing in 18% of patients. In 23 (23%) of 102 patients no inflamed diverticulum was demonstrable. This group included 17 patients with complicated diverticulitis and 6 false-negative cases. An inflamed diverticulum as a sign of diverticulitis yielded an overall sensitivity of 77% and a specificity of 99%. Sensitivity in uncomplicated disease was 96%. In patients with uncomplicated diverticulitis an inflamed diverticulum is a sign of diverticulitis with excellent sensitivity and specificity, usually with solitary and less frequently with more than one inflamed diverticulum being demonstrable. In patients with complicated diverticulitis an inflamed diverticulum is often not detectable.

SONOGRAPHY OF THE THYROID AND PARATHYROID GLANDS

Sonography is the first line modality for assessment of thyroid and parathyroid pathologies. Sonographic and color Doppler patterns of diffuse and focal pathologies of the thyroid are presented in this article. The accuracy of sonography in the localization of enlarged parathyroid glands is also discussed. The limitations of sonography in specifying focal thyroid diseases and the problems in localizing ectopic parathyroid adenoma are addressed.

New signs of breast cancer: High resistance flow and variations in resistive indices evaluation by color Doppler sonography

In a prospective study, color Doppler sonograms (CDS) were performed in 142 patients with solid breast lesions (64 carcinomas, 53 fibroadenomas, 25 miscellaneous breast diseases). Exclusively intratumoral RI were determined, with only the highest and lowest value in the various vessels of a tumor being considered. We found that an RI < 0.80 is typical for benign breast conditions, but also frequently occurs in malignant lesions. A significant difference was seen for higher RIs. An RI > or = 0.80 was seen to be an indicator of malignancy with high specificity (96%) and a sensitivity of 55%. Moreover, RI differences in malignant lesions were markedly greater than in benign lesions. An RI difference > or = 0.20 among vessels of one tumor was a malignancy indicator with very high specificity (97%) but relatively low sensitivity (39%). An RI > or = 0.80 and RI differences > or = 0.20 are specific Doppler ultrasound (US) malignancy indicators.

Transabdominal sonography of the gastrointestinal tract

Abstract. Like other cross-sectional imaging methods, transabdominal sonography is increasingly used for evaluation of gastrointestinal diseases. The potentials and limitations of sonography in evaluation of the gastrointestinal tract are discussed. Transabdominal sonography proved to be of clinical value in assessment of appendicitis, diverticulitis, bowel obstruction, chronic inflammatory bowel diseases, intussusception and infantile hypertrophic pyloric stenosis. The sonographic morphology of the most common gastrointestinal diseases is discussed. In experienced hands sonography can be used as primary imaging in several gastrointestinal diseases. The gastrointestinal tract should be included in the sonographic examination of the abdomen, especially if symptoms could be related to the intestine.

Suture granulomas: sonography enables a correct preoperative diagnosis

The purpose of this study was to examine if suture granulomas display distinct sonographic signs and if these signs enable an accurate preoperative diagnosis. In a retrospective and prospective study, the sonographic findings of 22 consecutive suture granulomas were investigated and correlated with subsequent operative results. The sonographic appearance of various surgical sutures in a water bath was also investigated. Sonography was performed with commercially available 5- to 13-MHz linear transducers. The sonographic findings of the suture granulomas included hypoechoic lesions in all cases and hyperechoic double or single lines within the hypoechoic lesions in 20 of 22 cases. Sonography enabled the correct preoperative diagnosis for the investigating radiologists in 20 cases. The sonographic appearance of sutures in a water bath was that of hyperechoic double or single lines. The sonographic signs of suture granulomas (hyperechoic double or single lines within hypoechoic lesions) indicate the correct preoperative diagnosis in a high percentage of cases.

Schwannoma of the brachial plexus: cross-sectional imaging diagnosis using CT, sonography, and MR imaging.

Abstract. Primary brachial plexus tumors are rare, usually benign, and in general have a good prognosis after surgical excision. We present a case of a schwannoma in which sonography enabled the correct diagnosis of a probably benign brachial plexus tumor. Key to the diagnosis was the demonstration of a smooth-bordered, longish, and well-defined nodule along a brachial plexus nerve root. Cross-sectional imaging modalities that provide a high degree of soft tissue contrast and spatial resolution, such as sonography and MR imaging, were suitable methods to establish the correct preoperative diagnosis. Findings at CT, sonography, MR imaging, and surgery are discussed.

Color Doppler sonography of normal breasts: detectability of arterial blood vessels and typical flow patterns

In a prospective study, 200 healthy female breasts were examined using color Doppler sonography to study the detectability and the resistive indices (RIs) of arterial vessels. In each breast, we attempted to detect two to three vessels and recorded the frequency spectrum with RI of each vessel. Blood vessels (n = 522) could be demonstrated in 196 (98%) breasts. Continuous diastolic flow (RI < 1) was found in 520 (99.6%) vessels. The mean RI of premenopausal women was 0.64; that of postmenopausal women was 0.70. This difference is highly statistically significant (p < 0.0001), but there is a marked overlap between the RIs of both groups. The variation in RI values of all women (up to 0.45), as well as in the breasts of the same woman (up to 0.31), was considerable. We conclude that modern color Doppler devices permit the detection of blood flow in the breast with regularity. Continuous diastolic flow (RI < 1) is a typical flow pattern. The variations of RI between women, and even for the same woman, are remarkable. The mean RI of premenopausal women is lower than the value for postmenopausal women.