PubMed Health⌕ Search

Biomedical subjects

A Hollerweger

Publications and source records attributed to A Hollerweger.

At least 19 recordsLinked to original sources
PubMed2006

Axillary sentinel lymph-node biopsy: gamma probe assisted sonographic localisation.

AIM: To evaluate axillary sentinel lymph-node (SLN) identification and localisation with gamma probe-assisted sonography. PATIENTS AND METHODS: The study comprises 42 patients. Sonographically guided peri-lesional injection of the radiopharmacon was performed on 40 breasts. Two patients with melanoma of the upper extremity underwent intracutaneous injection. After the acquisition of images with the gamma camera, the delineated lymph nodes were marked on the skin. A high-frequency transducer with an adapted gamma probe was then used to identify the SLN. Before surgery, the SLN was localised with a hook-wire. Node activity was controlled intraoperatively. RESULTS: In two out of 42 cases, lymphatic mapping did not reveal SLNs. Multiple SLNs at different sites, all with similar activity, were demonstrated in one patient, while in another patient the sonographically visible lymph nodes were too small for exact correlation. Hook-wire localisation of the SLN was performed in the remaining 38 axillary spaces. Gamma probe-assisted sonography allowed for correct localisation of SLNs in 35/38 patients (92 %). Localisation was not correct in 3 patients (8 %), but in all cases the hook-wire was located next to the SLN. CONCLUSION: Preoperative identification and correct localisation of the SLN is possible in a high percentage of cases. This method allows rapid intraoperative detection of the SLN and could be used for exact correlation of sonographic appearance and histopathological results.

Adult↗
PubMed2006

[Sonographic appearances of subcutaneous and cutaneous oedema -- correlation with histopathology].

PURPOSE: To correlate the sonographic findings of tissue oedema with histopathological changes in order to find an explanation for the different sonographic appearances of oedema. MATERIALS AND METHODS: Subcutaneous and cutaneous tissue of the chest wall, the abdominal wall, and the thigh of 4 human cadavers with clinically evident oedema were examined sonographically. A specimen was then taken from each region for histological examination. RESULTS: Twelve cutis-subcutis-regions underwent sonographic-histological correlation. 9 out of 12 subcutaneous regions exhibited a diffusely increased echogenicity. 5 of the 9 regions with increased echogenicity also showed hypoechoic bands (up to 3 mm) within the subcutaneous tissue. Histologically, all of the 9 sonographically altered subcutaneous regions displayed lentiform or band-like optically empty spaces within the connective tissue between lobules of fatty tissue as well as between groups of fat cells within lobules of fatty tissue corresponding to fluid. Hypoechoic stripes at sonography represented very broad bands of fluid. The cutis appeared hyperechoic in all cases. At histology, 9 of 12 cases exhibited uniformly distributed optically empty spaces between connective tissue fibres of the dermis. Dermal thickness corresponded to the degree of oedema. CONCLUSION: Subcutaneous oedema results in diffusely increased echogenicity, which is caused by the difference in acoustic impedance occurring at the edges of numerous bands of fluid. In addition, hypoechoic bands are observed if broad spaces of fluid are present in severe cases. Encased fluid in the dermis is uniformly distributed between connective tissue fibres. Sonographically, the homogenous hyperechoic appearance of normal dermis remains unaltered in cases of oedema, but dermal thickness increases.

Autopsy↗
PubMed2006

[Differential diagnosis of severe hypoechoic oedema of the small bowel].

PURPOSE: To demonstrate the different causes of a marked and hypoechoic edema of the small bowel. MATERIALS AND METHODS: The study comprises patients over a period of 6 years with hypoechoic oedema of the intestinal tract, especially with cystic appearance of the valvulae conniventes. The causes of severe oedema were analysed retrospectively. Examinations were performed with ATL-, Siemens-, and GE-units using convex transducers (2 - 5 MHz) and high-frequency linear transducers (5 - 13 MHz). RESULTS: Hypoechoic oedema of the small bowel with thickening of the valvulae conniventes was observed in 37 patients. The most frequent diagnoses in our series were small-bowel obstruction (n = 8), gastroenteritis (n = 5), peritonitis (n = 5), mesenteric venous thrombosis (n = 4), hereditary angiooedema (n = 3), tumorous infiltration of the mesentery (n = 3), and small bowel ischaemia (n = 2). Other reasons included one case of mesenteritis, renal insufficiency, vasculitis, use of ACE inhibitors, chemotherapy, intravenous drip after surgery, and protein loss in coeliac disease, respectively. CONCLUSION: Severe oedema of the gastrointestinal tract is caused by many different diseases. Hypoechoic thickening of the valvulae conniventes is the typical sonographic sign. Additional clinical, anamnestic and pathohistological data are necessary in order to make a specific diagnosis.

Angioedema↗
PubMed2005

["White bowel". A sonographic sign of intestinal lymph edema?].

AIM: We recently introduced the term "white bowel" to describe the hyperechoic appearance of the bowel wall found in a patient with HIV-associated enteropathy. The aim of this study was to describe changes of the bowel wall and to demonstrate possible causes of this phenomenon. PATIENTS AND METHODS: 10 patients identified as showing this phenomenon were enrolled in this study. The ultrasound examinations of the patients were re-evaluated with special regard to the echogenicity of the different layers of the bowel wall, to mesenteric lymph nodes, and to thrombosis of the mesenteric vein. RESULTS: Diagnosis in these 10 patients included: HIV-associated enteropathy aggravated by Mycobacterium avium-intracellulare infection (n = 3); endemic coeliac disease and complications arising from T-cell lymphoma (n = 2); carcinoma of the small and large intestine (n = 3); Whipple's disease (n = 2). Sonography typically showed echogenic thickening of the wall of the small intestine -- mainly of the mucosal layer. Enlarged mesenteric lymph nodes (with both hypoechoic and occasionally hyperechoic appearance) were present in the majority of cases. In 3 cases, mesenteric vein thrombosis was also demonstrable. CONCLUSION: The "white bowel" was found in patients with different diseases. Most of the patients showed enlargement of the mesenteric lymph nodes. Lymph oedema of the bowel wall probably constitutes the main reason for this phenomenon.

Adult↗
PubMed2003

[Acute left lower quadrant abdominal pain: ultrasonographic differential diagnosis].

Acute left lower quadrant pain is frequently caused by diverticulitis, especially in elderly patients. The most common differential diagnoses include renal colic, urinary tract infection, gynaecologic disorders, epiploic appendicitis, perforated carcinoma, other inflammatory diseases of the colon and diseases of the abdominal wall. Because the clinical impression may lead to a false diagnosis, further evaluation is necessary. Imaging methods are used to establish a correct diagnosis and to differentiate between benign self-limited disorders and those which require immediate intervention. Sonography and CT are the imaging methods of choice for the examination of patients with left lower quadrant pain. Both methods have shown to be accurate in verifying diverticulitis as well as in establishing alternative diagnoses. This review reports the sonographic appearance of the different entities and refers to other imaging methods if necessary.

Abdominal Pain↗
PubMed2002

Sonography of the salivary glands.

Due to their superficial position, the parotid, the submandibular, and the sublingual glands can be imaged with high-resolution transducers. In acute inflammatory diseases sonography can differentiate between obstructive or non-obstructive sialoadenitis. Abscess formations may be detected and the maturation of the colliquation may be controlled. Abscesses may be punctured under US guidance. In Sjögren's syndrome the sonographic changes correlate with the histological destruction, and in acute forms hypervascularization is found in color Doppler. In fibrotic cases the stimulation-induced hyperemia is impaired. In sialoadenosis inflammatory and tumorous lesions can be ruled out by sonography. Tumors of the salivary glands can be visualized with high sensitivity. Like other imaging methods the specificity in assessment of the histology of a tumor is low. Multilocular lesions, such as sarcoidosis, lymphoma, metastases, or cystadenolymphoma, are discussed. In deep located, malignant tumors or when the tumor cannot be delineated completely, MR or CT are obligatory to delineate the tumor. Sonography enables the diagnosis of cysts or ranulae. The accuracy of sonography in assessment of sialolithiasis is approximately 90%. Non-opaque stones can be visualized, too; however, small stones of less than 2 mm are difficult to detect since the posterior shadow may be missing. The concrements can be differentiated into intraductal or intraglandular stones. Indirect signs, such as ductal dilatations or inflammatory changes, may be found. Pseudotumorous lesions, such as hypertrophy of the masseter muscle, tuberculosis, sarcoidosis, or lymphoepithelial lesions in AIDS, are discussed. In children the main differential diagnosis of salivary gland pathologies are addressed. In many diseases sonography is the first-line imaging modality in assessment of salivary glands.

Diagnosis, Differential↗
PubMed2002

[Colonic diverticulosis: A comparison between sonography and endoscopy].

AIM: To investigate the ability of sonography to diagnose diverticulosis and to demonstrate the typical appearance of normal diverticula. PATIENTS AND METHODS: Sixty consecutive patients underwent sonography for prospective evaluation of the presence of diverticulosis of the left hemicolon. Diverticula were assessed for number, diameter, echogenicity, and wall thickness. Sonographic results were compared with those of endoscopy. RESULTS: Sonography yielded positive results in 28/33 patients (85 %) with endoscopically proven diverticulosis. Sonography on average could demonstrate less diverticula per patient than endoscopy. Two sonographic results were false positive. Diverticula had a maximum average diameter of 8.7 mm and the diverticular wall measured 1 mm at most. In many cases the diverticular wall could not be demonstrated by sonography. All diverticula except for one were hyperechoic. In 39 % of patients with diverticulosis one or more diverticula showed clear acoustic shadowing indicative of a faecalith. The maximum diameter of the colonic wall was 3.3 mm on average. Sonography could demonstrate the descending colon in all cases. The sigmoid colon was not visible in 3 cases and could rarely be evaluated in its entire length. CONCLUSION: Sonography can diagnose diverticulosis of the left hemicolon in most cases. Normal diverticula present as hyperechoic protuberances of the colonic wall with acoustic shadowing of varying intensity. The diverticular wall is thin and often not demonstrable at sonography.

Adolescent↗
PubMed2002

[Epiploic appendagitis: sonographic findings in 28 cases].

AIM: To investigate the sonographic signs of epiploic appendagitis in a larger number of patients and to add new details. PATIENTS AND METHODS: Over a period of approximately 8 years 28 patients were sonographically diagnosed to have epiploic appendagitis. The following sonographic signs were investigated: echogenicity of the lesion; compressibility; shape of the lesion; adherence to the anterior abdominal wall; peripheral rim; central hypoechoic line; thickening of the colonic wall. In 11 of these patients colour Doppler sonography was performed. In addition all 28 patients underwent CT. RESULTS: In 28/28 cases (100 %) a moderately hyperechoic, ovoid, non-compressible mass adjacent to the colon was demonstrated. The mass was surrounded by a hypoechoic rim in 20 cases (71 %) and was fixed to the abdominal wall in 26/28 cases (93 %). Five cases (18 %) revealed a central hypoechoic line, and slight thickening of the colonic wall was visible in 2 cases (7 %). In those cases where colour Doppler sonography was performed, colour flow was absent in the central part of the lesion. In the peripheral zone slightly increased colour flow was demonstrable in 9/11 cases. CONCLUSION: Epiploic appendagitis has a characteristic sonographic appearance with a moderately hyperechoic, ovoid, non-compressible lesion adjacent to the colon and adherent to the abdominal wall. The mass is frequently surrounded by a hypoechoic rim. Colour Doppler sonography shows a central avascular area and slightly increased colour flow in the peripheral zone.

Adult↗
PubMed2001

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

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.

Adolescent↗
PubMed2001

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.

Abdomen↗
PubMed2001

Outer diameter of the vermiform appendix as a sign of acute appendicitis: evaluation at US.

PURPOSE: To evaluate the usefulness and limitations of the outer diameter of the vermiform appendix at cross-sectional ultrasonography to confirm or rule out acute appendicitis. MATERIALS AND METHODS: In a prospective study, outer appendiceal diameters in 240 control subjects and in 278 patients suspected of having acute appendicitis who did (n = 98) or did not (n = 180) have acute appendicitis were measured. RESULTS: Outer appendiceal diameters in the control subjects ranged between 2 and 13 mm, and in 55 (23%) of 240 control subjects, diameters were 6 mm or more. Diameters in the symptomatic patients without acute appendicitis ranged between 2 and 11 mm, and 57 (32%) of 180 patients had diameters of 6 mm or more. Diameters of acutely inflamed appendices ranged between 6 and 30 mm. A diameter of 6 mm or more confirmed acute appendicitis with a sensitivity of 100%; a specificity of 68%; positive and negative predictive values of 63% and 100%, respectively; and an accuracy of 79%. CONCLUSION: The outer appendiceal diameter of 6 mm or more as a sign of acute appendicitis provides high sensitivity but limited specificity. This diagnostic criterion is more useful in excluding acute appendicitis than in confirming it.

Acute Disease↗
PubMed2001

Abdominal wall hernias: cross-sectional imaging signs of incarceration determined with sonography.

OBJECTIVE: The aim of this study was to determine with sonography whether distinct cross-sectional imaging signs exist that may differentiate between incarcerated and nonincarcerated abdominal wall hernias. SUBJECTS AND METHODS: The sonographic appearance of 149 consecutive abdominal wall hernias was prospectively investigated and correlated with subsequent surgical results. Commercially available 4- to 10-MHz linear transducers and 2- to 5-MHz curved transducers were used to evaluate the hernias. RESULTS: Surgery revealed 126 nonincarcerated and 23 incarcerated hernias. The sonographic signs suggestive of incarceration that we identified included free fluid in the hernia sac, which was observed in 91% of the incarcerated hernias and in 3% of the nonincarcerated hernias; bowel wall thickening in the hernia, which was detected in 88% of the incarcerated hernias and in none of the nonincarcerated hernias; fluid in the herniated bowel loop, which was detected in 82% of the incarcerated hernias and in 3% of the nonincarcerated hernias; and dilated bowel loops in the abdomen, which occurred in 65% of the incarcerated hernias and in none of the nonincarcerated hernias. These imaging findings allowed the identification of incarceration in all 23 cases and led to a false-positive result in two of 126 nonincarcerated hernias. CONCLUSION: Cross-sectional imaging signs indicating hernial incarceration included free fluid in the hernial sac, bowel wall thickening in the hernia, fluid in the herniated bowel loop, and dilated bowel loops in the abdomen. Sonography is an appropriate cross-sectional imaging modality for detecting these signs that are helpful in diagnosing patients with atypical clinical presentations.

Abdominal Muscles↗
PubMed2000

[Sonographic diagnosis of thrombosis of the calf muscle veins and the risk of pulmonary embolism].

AIM: To determine the frequency of deep vein thrombosis in the veins of the calf muscles. The risk of embolism in relation to the localisation of thrombosis was also evaluated. METHOD: 357 consecutive patients submitted for colour Doppler sonography of the lower extremities were prospectively examined for deep vein thrombosis (DVT). Both axial and muscular calf veins were investigated. 184 of these patients underwent additional investigation for pulmonary embolism. RESULTS: Diagnosis of DVT was made by means of colour Doppler sonography in 179 patients. Soleal veins (n = 88), peroneal veins (n = 84), the popliteal vein (n = 69), and the superficial femoral vein (n = 53) were the most common sites of thrombosis. Thrombosis of the gastrocnemial veins (n = 49) occurred less frequently. 85 patients (47% of all patients having DVT) showed isolated calf vein thrombosis, in 45 patients (25%) the gastrocnemial and/or soleal veins were the only site of thrombosis. 60% of patients with symptomatic DVT also had pulmonary embolism. The embolic frequency for isolated calf vein thrombosis and muscular calf vein thrombosis was 48% and 50%, respectively. CONCLUSION: The veins of the calf muscles are a common site of acute DVT and a source of pulmonary embolism. They should always be investigated in patients with suspected DVT of the calf, and in patients with pulmonary embolism.

Adolescent↗
PubMed2000

Presence or absence of gas in the appendix: additional criteria to rule out or confirm acute appendicitis--evaluation with US.

PURPOSE: To investigate whether the presence or absence of gas in the appendix may be considered as additional ultrasonographic (US) criteria to rule out or confirm acute appendicitis. MATERIALS AND METHODS: The appendices in 239 control subjects, 138 patients with lower right quadrant pain without acute appendicitis, and 80 patients with acute appendicitis were prospectively evaluated for intraluminal gas with US. RESULTS: The appendices in 206 (86%) control subjects showed gas at US, and those in 33 (14%) did not. The appendices in 109 (79%) symptomatic patients without acute appendicitis showed gas, and those in 29 (21%) did not. The appendices in 12 (15%) patients with acutely inflamed appendices showed gas, and those in 68 (85%) did not. The absence of gas as a criterion for acute appendicitis had a sensitivity of 85%; specificity, 79%; positive and negative predictive values, 57% and 94%, respectively; and accuracy, 81%. Gas was useful to exclude acute appendicitis in 64 (46%) symptomatic patients because the established criteria were misleading. In 19 (24%) patients, the absence of gas was useful for diagnosis of acute appendicitis because the other criteria were not convincing. CONCLUSION: US-based detection of gas in the appendiceal lumen helps to rule out acute appendicitis, whereas the absence of gas further confirms its presence, especially in cases where established US criteria are either insufficiently present or misleading.

Acute Disease↗
PubMed2000

Sigmoid diverticulitis: value of transrectal sonography in addition to transabdominal sonography.

OBJECTIVE: Overlying intestinal gas often impairs transabdominal sonographic assessment of the lower sigmoid colon. The aim of this study was to investigate the usefulness of transrectal sonography in addition to transabdominal sonography for the evaluation of sigmoid diverticulitis. SUBJECTS AND METHODS: Eighty-six consecutive patients with clinically suspected acute sigmoid diverticulitis were referred for transabdominal sonography as the initial imaging method. In 46 patients, transrectal sonography was performed in addition to transabdominal sonography if pain was localized to the mid lower abdomen and if a disease process could not be visualized or could be only partially visualized on transabdominal examination. An end-firing 5-9-MHz endocavitary probe was used for transrectal sonography. RESULTS: Thirty-four of 50 patients with a final diagnosis of sigmoid diverticulitis underwent both transabdominal and transrectal sonography. In 20 patients, transrectal sonography showed relevant additional information: six diagnoses of diverticulitis were established on transrectal sonography alone. Transrectal sonography revealed one perforation, five abscesses, and three fistulous complications that were not shown on transabdominal sonography. In the remaining five patients, correct diagnoses were supported on transabdominal examinations, but only transrectal sonography could show an inflamed diverticulum. In 10 patients, transrectal sonography revealed signs of diverticulitis but no relevant information in addition to the results from transabdominal sonography. Four false-negative and two false-positive results were revealed with transrectal sonography. CONCLUSION: Transrectal sonography is accurate for confirming clinically suspected acute colonic diverticulitis when the lower sigmoid colon is affected. It helps avoid false-negative results and defines the severity of disease in the lower sigmoid colon better than transabdominal sonography alone. Transrectal sonography can increase the sensitivity of sonography for diagnosing sigmoid diverticulitis.

Abdomen↗