[Automated breast ultrasound vs. handheld ultrasound: BI-RADS classification, duration of the examination and patient comfort]. / Automatisierter Brustultraschall vs. handgeführter Brustultraschall: BI-RADS-Einstufung, Untersuchungsdauer und Erlebnisqualität der Untersuchung.

PURPOSE: Automated breast ultrasound (ABUS) is a potentially valuable adjunct to mammography in breast cancer screening. The reliability and the inter-observer variability in the BI-RADS classification, compared to handheld ultrasound (US), as well as the duration of the examination and patient comfort have only been investigated in a limited number of papers to date. MATERIALS AND METHODS: In a prospective study, we examined 148 breasts of 76 patients with handheld US and ABUS. The ABUS data were evaluated separately by two investigators. Patient comfort was assessed using a standardized questionnaire. RESULTS: The inter-observer agreement for the BI-RADS classification among the two observers using ABUS was high (κ = 0,750), the agreement with handheld US was moderate. The sensitivity in the detection of breast cancer was 87.5 % for handheld US and 75 % for the ABUS evaluation by observer 1. The sensitivity was 87.5 % for the ABUS evaluation and 83 % for mammography by observer 2. The ABUS examination was rated as completely painless by 64 % of the patients. 25 % of the patients indicated minor pain, and 10 % indicated moderate pain. Handheld US was rated as completely painless by 66 % of the patients. 26 % of the patients indicated minor pain, and 8 % indicated moderate pain. CONCLUSION: ABUS examinations focusing on the BIRADS classification have low inter-observer variability, compared to handheld US. The sensitivity of ABUS did not differ significantly from handheld US.

[Sonography of the liver following CT staging of patients with lung cancer: a retrospective analysis]. / Sonografie der Leber nach CT-Staging von Patienten mit Bronchialkarzinom: eine retrospektive Analyse.

PURPOSE: Liver lesions are frequently detected in the CT staging of lung cancer patients and may require further investigation. The aim of our study was to assess the value of an ultrasound (US) examination of the liver in addition to routine CT staging. MATERIALS AND METHODS: In this retrospective study we included 174 consecutive patients with lung cancer who underwent US of the liver in addition to contrast-enhanced CT of the thorax and upper abdomen. The reports of the examinations were evaluated for the presence of liver lesions. Based on CT and US standard criteria, liver lesions were grouped into unequivocal cysts, hemangiomas, metastases and undefined lesions. RESULTS: With CT, liver lesions were detected in 56 / 174 patients (32 %). These included 24 cysts in 11 patients, 2 hemangiomas in 2 patients and 18 patients with liver metastases. In 31 patients, 66 small (< 1.5 cm) hypodense lesions were detected, which could not be further defined by CT. Using US, 21 of these 66 liver lesions were confirmed as benign (cysts, hemangiomas), and two lesions were diagnosed as metastases. In 2 patients US revealed metastases that were not visible on the CT scans. CONCLUSION: The study demonstrates that a complementary US of the liver in patients with lung cancer may reveal information relevant for treatment. Therefore, liver US may play an important role in the staging of lung cancer. When equivocal small liver lesions are detected with CT, a complementary US examination may help to diagnose these lesions or detect metastases not visible on the single-phase staging CT of the liver.

[Sonographic localization of non-palpable implanon hormone implants]. / Sonografische Lokalisation nicht tastbarer Implanon(R)-Hormonimplantate.

PURPOSE: Implanon is a rod-shaped hormone implant which leads to reliable contraception. The rod is implanted in the subcutis of the upper arm and is usually removed easily after its effective period. In the scenario where the rod is not palpable, the removal of the rod can be difficult or impossible. The purpose of this study was to evaluate the reliability of US in locating non-palpable Implanon implants and to investigate the optimal technical parameters for determining the location. MATERIALS AND METHODS: In a prospective study we evaluated 21 women between June 2004 and June 2008. In 14 patients previous examinations with US, radiography, CT and/or MRI were non-diagnostic. The US evaluation followed a standardized protocol in transverse and longitudinal sections. The technical parameters US frequency, position and number of focal zones and compound imaging were varied to define the optimal parameters for the visualization of the Implanon implant. RESULTS: The Implanon implant was detected in all 21 patients. Reasons for negative palpability were mainly an intramuscular or subfascial location as well as a significant migration of the Implanon implant in 2 patients. The use of a high US frequency, the position of the focal zones in the near field and the deactivation of compound imaging all facilitate visualization of the characteristic US morphology of the plastic rod. CONCLUSION: High resolution US is the method of choice for determining the location of non-palpable Implanon implants. Knowledge of US morphology and optimal technical settings as well as the use of high-resolution scan heads are essential for determining the correct location.

Cervical ultrasound (US) and US-guided lymph node biopsy as a routine procedure for staging of lung cancer.

PURPOSE: To assess the value of routine ultrasound evaluation and US-guided fine-needle aspiration biopsy of supraclavicular lymph nodes for the diagnosis, staging and treatment of patients with lung cancer. MATERIALS AND METHODS: 300 consecutive patients with lung cancer were evaluated with high-resolution ultrasound for the presence of pathological lymph nodes (criteria: short-axis >or= 5 mm, rounded shape, missing echogenic hilum). Suspicious lymph nodes were biopsied under ultrasound guidance if the result could influence further patient management RESULTS: In 41 of 257 NSCLC patients (16 %) and 15 of 43 (35 %) SCLC patients, enlarged lymph nodes were detected, in particular in patients with a CT stage N2 or N3 (NSCLC) or extensive disease (SCLC). 16 lymph node biopsies were positive for malignancy, 4 biopsies were negative for malignancy or not diagnostic. US had a higher sensitivity for the detection of pathological lymph nodes than CT. CONCLUSION: Routine ultrasound evaluation of supraclavicular lymph nodes reveals suspicious lymph nodes in a high number of patients with lung cancer. High-resolution US is superior to CT in the detection of pathological lymph nodes. Ultrasound-guided biopsy proves malignancy and thereby a N3 or M1 stage. Thus, more invasive and expensive diagnostic procedures can be avoided.

Ultrasound of the kidney: obstruction and medical diseases.

Ultrasound has emerged as the primary imaging modality in conditions where either renal obstruction or renal medical disease is suspected on the basis of clinical and laboratory findings. In urinary tract obstruction, pathophysiologic changes affecting the pressure in the collecting system and kidney perfusion are well understood and form the basis for the correct interpretation of real-time US and color Doppler duplex sonography (CDDS). Ultrasound is very sensitive for the detection of collecting system dilatation ("hydronephrosis"); however, obstruction is not synonymous with dilatation, as either obstructive or nonobstructive dilatation may be present. To differentiate these conditions, CDDS with measurement of the resistive index (RI) in the intrarenal arteries is extremely helpful, as obstruction (except in the peracute stage) leads to intrarenal vasoconstriction with a consecutive increase of the RI above the upper limit of 0.7, whereas nonobstructive dilatation does not. Diuretic challenge to the kidney may further enhance these differences in RI between obstruction and dilatation. Based on these findings, the present value of US and CDDS in the assessment of the patient with flank pain or renal colic is suggested, especially with respect to promising results for spiral CT and based on cost analysis. In renal medical disease, distinguishing different pathologic conditions using gray-scale US and CDDS (RI) criteria is still very difficult. Nevertheless, US is the fist-line imaging modality in the patient with renal insufficiency.

Role of Doppler sonography in the evaluation of accessory spleens after splenectomy.

OBJECTIVE: Splenectomy influences the Doppler blood flow pattern in the splenic artery. Blood flow in this vessel might return to normal if an accessory spleen increases in size after splenectomy. Our objective was to evaluate the resistive index of the splenic artery depending on the presence or absence of a hypertrophic accessory spleen in splenectomized patients. METHODS: The resistive index of the splenic artery was evaluated by duplex Doppler sonography in 19 splenectomized patients (8 with a hypertrophic accessory spleen) and in 8 healthy volunteers. The resistive index was measured within 3 cm of the origin of the splenic artery, and 3 different measurements were averaged. The presence or absence of a hypertrophic accessory spleen was diagnosed on the basis of sonography, computed tomography, magnetic resonance imaging, or scintigraphy, as well as by the presence or absence of Howell-Jolly bodies on a peripheral blood smear. RESULTS: The resistive index of the splenic artery in the splenectomized patients without a hypertrophic accessory spleen (mean +/- SD, 0.82 +/- 0.06; n = 11) was significantly (P < or = .0001) higher than in splenectomized patients with a hypertrophic accessory spleen (0.63 +/- 0.06; n = 8) and in control subjects (0.63 +/- 0.05; n = 8). CONCLUSIONS: In the splenectomized patient, a hypertrophic accessory spleen is associated with a normal resistive index in the splenic artery.

Spiral CT of the lung in children with malignant extra-thoracic tumors: distribution of benign vs malignant pulmonary nodules.

The purpose of this paper is to clarify the distribution of benign vs malignant pulmonary nodules which are seen on spiral CT in children with malignant extra-thoracic solid tumors. Seventy-four children with known solid, extra-thoracic tumors underwent spiral CT of the chest. According to the initial and follow-up (interval 9.2+/-4.7 months) findings, the children were graded into four groups: I = normal; II = solitary nodule unchanged at follow-up; III = multiple nodules with one or more than one unchanged at follow-up; and IV = solitary or multiple nodules all changed at follow-up. Nodules without change at follow-up were regarded as benign. Forty-nine children did present with normal pulmonary CT exams. In 7 cases solitary pulmonary nodules were found unchanged (group II) at follow-up and in 2 cases (group III) some of the nodules were stationary. Thus, 12% (9 of 74) presented with at least one pulmonary nodule that did not change at follow-up. Solitary nodules (in groups II and IV) with a diameter <5 mm were in 70 % (7 of 10) unchanged at follow-up and regarded as benign. In children with known solid extra-thoracic tumors at initial presentation, 70% of solitary nodules ( <5 mm) may be benign. To avoid overstaging, smaller solitary nodules must not automatically be regarded as metastases.

Randomized in vitro and in vivo evaluation of different biopsy needles and devices for breast biopsy.

In an experimental study (in vitro and in vivo) we evaluated the efficacy of various biopsy needles/devices for breast biopsy. In vitro, biopsies of five human cadaveric breast specimens were performed using 33 different needles/devices ranging from 14 to 20-gauge. Of these 33 needles/devices, 22 optimally performing needles were selected for the in vivo study. In the clinical part of the study, 44 breast lesions were randomly biopsied with each of the 22 needles/devices under stereotactic guidance. Tissue specimens were analysed quantitatively and qualitatively. Several automatic long-throw guns (Acecut, Asap, Biopty, Magnum) obtained greater tissue areas and had a better histopathologic score than the conventional type of a side-notch needle like Trucut, an aspiration needle like Surecut, or an end-cut needle like Autovac. The automatic long-throw guns performed better than the short-throw Monopty gun. Regardless of needle size (14-20-gauge), breast biopsies should be routinely performed with automated long-throw side-notch guns (Acecut, Asap, Biopty, Magnum).

The postoperative spine.

During the last decade, magnetic resonance imaging (MRI) mostly has replaced computed tomography for evaluation of spinal surgery patients. The inherent advantages of MRI are obvious for this particularly difficult field of imaging. With MRI, it is possible to demonstrate anatomic as well as pathological and iatrogenic changes in three different imaging planes and countless neighboring planes and to obtain a superior view of the complex postoperative situation regardless of the spinal level imaged. Soft-tissue masses in particular can be identified more readily and located within three-dimensional space. One of the major advantages is that the nature and histology of the mass can be estimated precisely using different MR sequences in combination with intravenous contrast media. The most important benefit may be demonstration of inflammatory and hemorrhagic masses in the early postoperative periods (with special emphasis on alterations visible in the spinal cord itself) as well as repair processes and ongoing degeneration in later stages. This visualization is possible even when their extent is limited. In the postoperative spine, the application of MRI was facilitated with the advent of new materials, such as titanium alloys, used for surgical instrumentation. These new materials limit the amount of artifacts visible on MR images. Earlier implants made of other metallic material prohibit the use of computed tomography in the spine. This article provides a brief overview of the progress in spinal surgery and focuses on the developments in MRI techniques during the last decade. Technical questions about imaging of spinal instrumentation are discussed. "Normal" postoperative findings needed for interpretation of pathologic conditions are also discussed. Finally, the most important frequently asked questions from referring surgeons that radiologists must be able to answer by MRI are presented.

Pulmonary and aortic blood flow measurements in normal subjects and patients after single lung transplantation at 0.5 T using velocity encoded cine MRI.

PURPOSE: It is the purpose of this study to compare pulmonary and aortic blood flow measurements obtained in patients after single lung transplantation (SLTX) with those in volunteers. METHODS/MATERIAL: In nine patients after SLTX (three male, six female) and nine volunteers (seven male, two female), double oblique phase contrast cine-MRI sequences perpendicular to the direction of blood flow were obtained in the ascending aorta, main, right, and left pulmonary artery on a 0.5-T unit (Philips Gyroscan; Best, the Netherlands) (repetition time, 600 to 800 ms; echo time, 8 ms; alpha=30; field of view=280 mm matrix, 128x256, ECG gating, temporal resolution 16 time frames/RR interval). An initial in vitro study using the same sequence on a nonpulsatile flow phantom showed excellent correlation (r=0.99) between MRI measurements of flow velocity and flow volume and true velocity and flow volume. Measurements of blood flow volume (mL/min), peak mean systolic velocity, resistive index, and distensibility index were obtained in each vessel. RESULTS: We found excellent correlations between left and right cardiac output as measured by velocity encoded cine-MRI (VEC-MRI) in the ascending aorta and main pulmonary artery both in normal volunteers (r=0.95) and in patients (r=0.91). Differential pulmonary blood flow measurements in volunteers showed that 55% of the right cardiac output was directed to the right and 45% to the left lung. Differential pulmonary blood flow in patients showed that most of the blood flow (81%) reaches the transplanted lung and only 19% reaches the patient's own lung (SLTX: 4.5+/-1.8 L/min, patient's own lung: 1.2+/-0.8 L/min). There were significant differences (p<0.05) in peak mean systolic velocity and resistive index obtained in the pulmonary arteries, both between normal volunteers and patients and between measurements obtained in the patient's own lung and the transplanted lung. CONCLUSION: VEC-MRI blood flow measurements are a promising noninvasive tool to monitor the hemodynamic changes of pulmonary blood flow after SLTX.

[Ewing sarcoma. Diagnostic imaging]. / Das Ewing-Sarkom. Bildgebende Diagnostik.

Ewing's sarcoma is a highly malignant neoplasm of the bone whose origin is still uncertain. A strong relationship exists between Ewing's sarcoma and tumors of neural origin (Ewing family of tumors). Ewing's sarcoma must be distinguished from other round-cell tumors like lymphoma and neuroblastoma and also must be differentiated from osteogenic sarcomas. On plain radiographs, Ewing's sarcoma appears as a lytic or mixed lytic-sclerotic, rarely as predominantly sclerotic lesion with margins Lodwick grade III. It is located primarily in the diaphyseal and metadiaphyseal regions of the long bones of the lower extremities. A large soft tissue tumor is usually present. Magnetic resonance imaging is the imaging modality of choice to evaluate the extent of the primary lesion, to monitor the response to neoadjuvant chemotherapy and to follow up non-resected Ewing's sarcomas. Bone scintigraphy is necessary to detect skeletal metastasis, and 201thallium scanning has been shown to be sensitive in the monitoring of treatment response. Today, computed tomography is not longer used to image the tumor site; however, spiral CT of the lungs plays a central role as a staging and follow-up tool.

Evaluation of needle size for breast biopsy: comparison of 14-, 16-, and 18-gauge biopsy needles.

OBJECTIVE: The purpose of our study was to compare the quantity and quality of tissue harvested from breast biopsy when using 14-, 16-, and 18-gauge "long-throw" needles. SUBJECTS AND METHODS: We performed a prospective randomized study in 64 patients with 66 breast lesions. Under stereotactic guidance, passes were made in random order with each of the three biopsy needles in each lesion. Samples were measured for tissue area and scored for their quality. All lesions, including benign and malignant lesions and lesions with and without microcalcifications, were analyzed. Findings of the biopsy samples were compared with the final diagnoses made at surgical excision. RESULTS: In all 66 lesions, 14-gauge biopsy needles obtained significantly larger specimens (14-gauge, 13.14 mm2; 16-gauge, 9.6 mm2; 18-gauge, 6.41 mm2; p < .05) and scored significantly better (14-gauge, 8.37; 16-gauge, 7.56; 18-gauge, 7.14; p < .016) than either of the smaller needles. The results for malignant and benign lesions and for lesions with and without microcalcifications were similar but not equal to the overall results. However, benign lesions and areas with microcalcifications seem to be more problematic for both smaller needles than for 14-gauge needles. CONCLUSION: Our results indicate that the quantity and quality of breast biopsy specimens depend on the needle size. Of the three needle sizes tested, only 14-gauge long-throw biopsy needles can be recommended for breast biopsy.

Central nervous system disease in Langerhans cell histiocytosis.

Central nervous system (CNS) disease in Langerhans cell histiocytosis (LCH) is a poorly understood complication of yet unknown frequency. By far the most common manifestation is in the hypothalamic-pituitary system with diabetes insipidus as the leading sign, followed by other endocrinopathies and hypothalamic dysfunction. However, essentially all other parts of the CNS may be involved. On the one hand, space-occupying histiocytic infiltrates may lead to size- and site-depending symptoms, extending from adjacent bone lesions or arising from the meninges or choroid plexus. On the other hand, a progressive neurological deterioration can occur with mainly cerebellar-pontine symptoms. In this article, these clinical patterns are described in correlation with the morphology on MR imaging and histopathology. Further, the therapeutic strategies are reviewed critically, and guidelines for the management of patients with LCH-related CNS disease are presented.

Overuse edema in the bone marrow of the hand: demonstration with MRI.

In MRI of the skeleton, marrow edema is a frequent finding that can be caused by avascular necrosis, fracture, bone bruises, transient osteoporosis, osteomyelitis, primary tumors, metastases, and altered biomechanical properties. We examined a 29-year-old woman golfer with mild pain and swelling of the proximal phalanx II of the left hand. No signs of a stress fracture were seen on the MR images or plain radiographs. MRI revealed increased signal intensity on T2-weighted images in the metacarpal and proximal phalanx II in the left hand. We concluded that bone marrow edema may be the result of physiologic bone response to stress and may not necessarily correspond with severe trauma. Our case complements recent observations outlining the influence of altered biomechanics as a reason for marrow edema.