A connection between neurovascular conflicts within the cerebellopontine angle and vestibular neuritis, a case controlled cohort study.

This retrospective, observer blinded case-control study aims to compare the prevalence of neurovascular conflicts (NVCs) of the vestibulocochlear nerve and the anterior inferior cerebellar artery (AICA) in patients presenting with clinical signs of acute vestibular neuritis with and without subsequent objective vestibular function loss (VFL). 58 acute cases of clinically suspected acute vestibular neuritis were investigated with same day cranial MRI at a tertiary referral centre and compared to 61 asymptomatic controls. The prevalence of NVCs in cases with objective VFL were also compared to cases without VFL. Radiologists described the NVC as "no contact" (Grade 0), "contact < 2 mm" (Grade 1), "contact > 2 mm" (Grade 2) and "vascular loop presence" (Grade 3) without knowledge of neurotological data. Neurotological data was collected without knowledge of MRI findings. Vestibular function was tested by bithermic caloric irrigation. 26 cases (45%) showed caloric VFL (Group A), whereas 32 (55%) exhibited no VFL (Group B). Group A included 13 cases with NVCs (50%), Group B included 26 NVC cases (82%) (p = 0.012) and the control group included 16 individuals (26%) (p < 0.001 for comparison of all 3 groups). Group B had a significantly higher NVC-Grading than Group A (p = 0.009). There was no statistically significant association between NVCs and either SNHL or tinnitus (p > 0.05). Our results suggest that patients presenting with clinical signs of acute vestibular neuritis who show symmetrical caloric vestibular function test results have a significantly higher NVC prevalence in the cerebellopontine angle.

Magnetic resonance imaging of the lower vertebral column in patients with multiple myeloma.

Eighteen patients with multiple myeloma (clinical stages 1-3) and a control group of 21 persons underwent magnetic resonance imaging (MRI) studies of the lower thoracic and lumbar spine. This was done to determine the potential benefit of MRI in addition to conventional radiographs, tomograms, computed tomography and nuclear scans. In addition to focal fatty replacement of normal hematopoietic marrow, which presented as focal hyperintense lesions on T1-weighted images (T1-WI) and on T2-weighted images (T2-WI), two types of myelomatous lesions were found: (1) focal areas with reduced signal intensity when compared with normal bone marrow on T1-WI and enhanced signal intensity on T2-WI, mainly found in untreated myelomas; and (2) focal areas of decreased signal intensity on T1-WI and on T2-WI, which were predominantly detected after previous radiation therapy. MRI surpassed conventional radiography in detecting abnormal focal marrow infiltration in 41 of 247 vertebrae. Radiographs identified only 11 of the 41 as pathologic, based on shape and structure of the vertebral bodies; however, 15 other collapsed vertebrae showed no signal abnormalities of the marrow on MR images. Discrimination of normals and abnormals by statistical analysis of intensity measurements of the bone marrow was not possible.

Gated magnetic resonance imaging for assessment of cardiac function and myocardial infarction.

Gated magnetic resonance imaging (MRI) is a promising noninvasive imaging modality capable of evaluating cardiac function and blood flow in the great vessels. MRI detects acute and chronic myocardial infarctions in experimental animals and in man.

Clinical outcome two years after implantation of a transjugular intrahepatic portosystemic shunt for recurrent variceal bleeding.

OBJECTIVE: Implantation of a transjugular intrahepatic portosystemic shunt (TIPS) is a relatively new therapy for variceal bleeding. The aim of this study was to assess clinical course 2 years after TIPS procedure. DESIGN: The study was designed as a prospective, uncontrolled cohort study. METHODS: Forty-six patients who underwent successful TIPS implantation were followed prospectively by clinical examinations, duplex sonography and portal venography. Mean follow-up in surviving patients was 24.1 +/- 9.0 months. RESULTS: The cumulative rate of survival was 80.4% at 1 year and 70.2% at 2 years. The cumulative rebleeding rate was 12.4% at 1 year and 21.3% at 2 years. The mortality rate of episodes of variceal rebleeding was 22.2%. Variceal rebleeding was associated with shunt abnormalities, and successful shunt revision resulted in control of the bleeding. The cumulative incidence of shunt stenosis or occlusion was 41.2% at 1 year and 54.9% at 2 years. Of those patients without shunt abnormalities after 1 year, 23.3% developed shunt stenosis or occlusion during the second year after TIPS procedure. Shunt revision was successful in 96.6% of cases. Secondary patency rate was 88.1% after 2 years. CONCLUSION: Successful TIPS implantation results in a low rate of morbidity and mortality from variceal rebleeding over 2 years. TIPS creation in combination with careful follow-up examinations represents an effective long-term treatment of recurrent variceal bleeding. Even in patients in whom no shunt abnormality is detected during the first year, routine duplex follow-up examinations should be continued at 3-month intervals.

Contrast MRI in multiple endocrine neoplasia type 1 (MEN) associated with renal cell carcinoma.

The radiologic work-up of a patient with multiple endocrine neoplasia type 1 (MEN 1) syndrome and multiple endocrine nodules, with coincidental renal cell carcinoma, is described. Parathyroid adenoma was differentiated from multiple thyroid nodules by gadolinium-enhanced MRI. Adrenal enlargement due to a nonfunctioning adenoma and a renal cell carcinoma next to a simple renal cortical cyst were identified by typical signal intensities on T1- (pre- and post-Gd-DPTA) and T2-weighted images. Insulinoma was visualized only retrospectively.

Evaluation of pleural and pericardial effusions by magnetic resonance imaging.

MR examinations of 36 patients with pleural and/or pericardial effusions were retrospectively evaluated. The purpose of this study was to determine of MR imaging is capable of differentiating between pleural and pericardial effusions of different compositions using standard electrocardiogram (ECG)-gated and non-gated spin echo pulse sequences. Additional data was obtained from experimental pleural effusions in 10 dogs. The results of this study indicate that old hemorrhages into the pleural or pericardial space can be differentiated from other pleural or pericardial effusions. However, further differentiation between transudates, exudates and sanguinous effusions is not possible on MR images acquired with standard spin echo pulse sequences. Respiratory and cardiac motion are responsible for signal loss, particularly on first echo images. This was documented in experiments in dogs with induced effusions of known composition; "negative" T2 values consistent with fluid motion during imaging sequences were observed in 80% of cases. However, postmortem studies of the dogs with experimental effusions showed differences between effusions with low protein concentrations and higher protein concentrations. We conclude from our study that characterization of pleural and pericardial effusions on standard ECG-gated and non-gated MR examinations is limited to the positive identification of hemorrhage. Motion of the fluid due to cardiac and respiratory activity causes artifactual and unpredictable changes in intensity values negating the more subtle differences in intensity associated with increasing protein content.

Comparison of Duplex sonography and color Doppler imaging in renal allograft evaluation: a prospective study.

A prospective study compared the diagnostic capability of quantitative Duplex sonography (DS) and color Doppler imaging (CDI) in 49 consecutive patients with 50 renal allografts. Sixty five DS examinations and 65 CDI examinations were performed by two independent investigators on two different machines on the same day. The resistive index (RI) was calculated and the color flow of renal arteries was observed up to the arcuate arteries. There was good correlation of RI values obtained by DS and CDI at all vascular sites. Thirty one allografts were functioning stably and 19 were in a state of dysfunction, defined by histology (n = 17). Forty allografts presented with a RI less than 0.9 and normal color flow. All five allografts with a pathologic RI greater than or equal to 0.9 showed abnormal color flow (missing flow in arcuate and/or interlobar arteries). Five allografts had a RI less than 0.9 but abnormal color flow, possibly due to atrial fibrillation, hypertension, heart failure or a combination of these. A normal color flow pattern excludes severe vascular compromise to the allograft. In addition, CDI revealed three biopsy-related vascular lesions; two of them had been missed by DS.

[Magnetic resonance tomography of the heart. Experimental study of a non-invasive characterization of myocardial tissue]. / Magnetische Resonanztomographie (MRT) des Herzens. Experimentelle Studie zur nicht-invasiven Gewebscharakterisierung des Myokards.

In this experimental study (canine heart) a variety of pathologic conditions of the myocardium were studied using ECG-triggered magnetic resonance imaging (MRI). The purpose of this study was to examine the MR appearance and the T2 relaxation times of occlusive and reperfused myocardial infarcts, of hypertrophic cardiomyopathy, and of cardiac transplants with and without acute cardiac allograft rejection. MR images were correlated with the results of histology and tissue water content. MRI identified normal myocardium with T2 values of 38 (+/- 4.3) msec. Myocardial infarcts and acute allograft rejection had significant (p less than 0.05) longer T2 values compared to normal myocardium. On the basis of T2 relaxation times no further differentiation among different pathologic entities was possible. Therefore, it is necessary to include morphologic criteria such as myocardial wall thickness, cardiac chamber size and intracavitary blood flow signal in the interpretation of cardiac MR tomograms.

[Diagnosis of acute subarachnoid hemorrhage--MRI with 0.5 Tesla with FLAIR sequence]. / Diagnostik der akuten Subarachnoidalblutung--MR bei 0,5 Tesla mit der FLAIR-Sequenz.

PURPOSE: Evaluation of MR imaging in patients with acute subarachnoid hemorrhage (SAH) at 0.5 Tesla using the FLAIR (Fluid Attenuated Inversion Recovery) sequence. Additionally, the value of MR angiography (MRA) in the diagnosis of intracranial aneurysms was assessed. MATERIALS AND METHODS: 19 patients with suspected acute SAH were included in this study. MR imaging was performed using an axial FLAIR sequence and axial T1, T2 and PD weighted sequences. In 16 patients an additional MRA (3D-TOF) was performed. 10 patients without SAH were examined as a control group. At the end of the study the 29 MR examinations were randomised and the images were read by two experienced radiologists; subsequently a consensus interpretation was made. RESULTS: In 16 patients an acute SAH was verified with the FLAIR sequence, in 13 cases the origin of hemorrhage was found during surgery. In the consensus interpretation of the MR images all cases were diagnosed properly. 12 of the 16 MRA studies were of diagnostic quality, but only 6 cases were interpreted correctly. CONCLUSION: The FLAIR sequence at 0.5 Tesla proved effective in the diagnosis of acute SAH. MRA at 0.5 Tesla failed in the detection of intracranial aneurysms.

[Radiologic and endoscopic correlation in Crohn's disease of the colon]. / Radiologisch-endoskopische Korrelation bei Crohnscher Erkrankung des Kolons.

A comparative assessment was carried out in 47 patients with double-contrast irrigoscopy (DCI), colonoscopy and endoscopy, the confirmed diagnosis being Crohn's disease in each of the patients. However, the histological finding of Crohn's disease was established in 19% only of the endoscopic biopsies. DCI enabled a more comprehensive assessment of the entire colon than was possible via endoscopy, since the right half of the colon could be visualized in less than 50% of the patients by the endoscopic method, whereas roentgenologic visualization of this part of the colon was possible in more than 90% of the patients. There was good agreement in respect of parts of the colon visualized both via endoscopy and via x-ray examination. As far as the assessment of deeper mucosal lesions was concerned, radiology proved superior, whereas endoscopy offered advantages in respect of changes on the level of the mucosa.

[Sonography of the thyroid gland with high-resolution real-time equipment]. / Sonographie der Schilddrüse mit hochauflösenden real-time-Geräten.

The results of sonography of thyroid glands in 131 patients were compared with the findings on palpation and from scintigrams. High resolution sonography is the most accurate method of examination for demonstrating changes in the thyroid. In 40% cases sonography demonstrated lesions additional to the single abnormality found clinically. In 10% cases a suspected thyroid abnormality on palpation proved to be due to extra thyroid disease. Evaluation of the number, size and localisation of space-occupying lesions by means of sonography is superior to all other kinds of investigation. It is, however, not possible to determine whether a lesion is benign. An attempt has been made to define the usefulness of thyroid sonography and its place during routine diagnosis.

[Sonographic problems in the assessment of abdominal aortic aneurysms]. / Sonographische Probleme bei der Beurteilung von Aneurysmen der Aorta abdominalis.

Ultrasound has taken a solid position in the diagnostic management of aneurysms of the abdominal aorta as it is a non-invasive, simple and quickly practicable method with a low expenditure. After clinical examination ultrasound holds the second place in the sequence of various diagnostic procedures in the case of an aneurysm of abdominal aorta. Diagnostic problems are demonstrated in the sonographic judgement of aortic aneurysms. 42 patients with an abdominal aortic aneurysm have been evaluated in relation to the sonographic features of the aneurysm.

[Hypertrophic pyloric stenosis--an indication for sonography]. / Hypertrophe Pylorusstenose--eine Indikation zur Sonographie.

The pyloric region of 58 infants who presented with vomiting was examined by real-time ultrasound. Transverse diameter of the pylorus and single wall thickness were measured. In 18 patients sonographic diagnosis of hypertrophic pyloric stenosis (HPS) was made and subsequently confirmed by surgery. The mean (+/- one standard deviation) of the transverse diameter and of the pyloric wall thickness in patients with HPS was 15 (+/- 1) mm. and 5.5 (+/- 0.7) mm., respectively. Forty infants matched for age and sex distribution without gastrointestinal symptoms served as controls. The measurements for the transverse diameter were 9.6 (+/- 1.8) mm. and for the wall thickness 1.9 (+/- 0.5) mm. Diameter values of patients with HPS were significantly (p less than 0.001) higher than those of the control group and those of the remaining 40 patients without HPS. Real-time sonography proved a reliable tool in the diagnosis of HPS.

[The role of chest X-rays in the diagnosis of thoracic aortic aneurysms]. / Die Rolle des Thoraxröntgens in der Diagnose des thorakalen Aortenaneurysmas.

OBJECTIVE: To evaluate the role of routine chest radiographs in the diagnosis of thoracic aortic aneurysms (TAA). METHODS: An electronic full-text search was performed in our radiological information system for all patients who underwent chest radiograph under standard conditions between 1998 and 2000 and who had suspected widening or aneurysm of the thoracic aorta as a diagnosis. Computed tomography (CT) of the thorax was used as the gold standard and had to be performed within a period of 30 days. Two independent and blinded observers evaluated different morphologic and morphometric parameters in the diagnosis and correlated the results with those of CT. RESULTS: 28 patients were included in the present trial. With almost perfect interobserver correlation (r = 0.95) both investigated morphometric parameters correlated well (r = 0.85 and 0.83) with the diameter of the aorta as evaluated with CT. While a low subjective over-all probability for TAA had a negative predictive value of 100 %, we found that, despite an almost perfect interobserver variability (Kappa > 0.8), none of the investigated morphologic parameters (discrepancy between the ascending and descending aorta, displacement of the trachea to the right and caudal displacement of the left main bronchus) was significantly correlated with the final diagnosis. CONCLUSION: The investigated morphometric parameters help to estimate the diameter of the aorta in the arch and in the descending section, but none of the morphologic criteria can be used for the diagnosis of TAA.

[Extended field-of-view sonography in Achilles tendon disease: a comparison with MR imaging]. / Panorama-Ultraschall in der Abklärung symptomatischer Achillessehnenerkrankungen: ein Vergleich zur MRT.

PURPOSE: To evaluate the role of real-time extended field-of-view sonography (EFOVS) in symptomatic Achilles tendon disease in comparison with MR imaging (MRI). MATERIALS AND METHODS: Twenty-three symptomatic tendons were examined by conventional grayscale sonography, EFOVS and MRI, which served as the gold standard. RESULTS: The median tendon thickness in MRI was 7.8 mm (IQR 3.1) and correlated significantly to the results of EFOVS (7.0 mm, IQR 2; r = 0.74, P < 0.01). In total, MRI detected 24 lesions in 18 tendons and EFOVS 21 hypoechoic lesions in 15 tendons, corresponding to a sensitivity of 87.5 % and specificity of 100 %. The additional usage of conventional grayscale sonography improved sensitivity to 95.8 %. The median distance of the largest lesion to the calcaneal tuberosity was 10.4 mm (IQR 3.4) in MRI and 8.5 mm (IQR 5.1) in EFOVS (r = 0.64; P < 0.05). The sensitivity and specificity of EFOVS for the detection of a peritendinitis were 63.6 % and 66.7 %, respectively. Corresponding values for the detection of a bursitis were 68.8 % and 28.6 %. The additional usage of conventional grayscale sonography improved the specificity to 85.7 %. CONCLUSION: The combination of EFOVS and grayscale sonography has the potential to challenge MRI as the preferred imaging method in diagnosing symptomatic Achilles tendon disease, especially with respect to saving time and cost and the absence of any contraindications.

[Hepatic and splenic abscesses in immunosuppressed patients]. / Hepatale und lienale Abszesse bei immunsupprimierten Patienten.

Morphologic characteristics of hepatosplenic abscesses using ultrasound and CT examinations in 13 immunosuppressed patients are presented. Additionally, the results of diagnostic ultrasound and CT guided biopsy procedures (n = 13) are reported. On sonograms, bacterial abscesses were exclusively hypoechoic lesions whereas patients with mycotic abscesses showed additionally target lesions and lesions presenting a "wheels-within-wheels" appearance. Thus, with some limitations, us might help to differentiate between fungal and bacterial abscesses. On CT, all patients presented uniformly with hypodense lesions. Follow-up ultrasound studies showed these abscesses over periods as long as 24 months; biopsy proved some of these as fibrotic lesions without vital bacteria or fungi.

[MRT using Gd-DTPA in the diagnosis of tumor and pseudotumor intracardiac masses]. / MRT mit Gd-DTPA in der Diagnostik tumoröser und pseudotumoröser intrakardialer Raumforderungen.

Magnetic resonance examinations were performed in 15 patients suffering from echocardiographically detected intracardiac masses. All patients were examined with a 1.5 T superconducting machine, using spin echo technique, including Gd-DTPA, and gradient echo sequences. The MR findings were confirmed partially by histology and angiography, otherwise by good correlation to clinical findings. MR results were divided into three groups: 1. tumour, 2. thrombosis, 3. pseudotumorous mass, and corresponded well with the final diagnosis: in 8 patients tumour, in 5 patients thrombosis, and in two patients pseudotumorous masses, including one hydatid cyst and one case of lipomatosis. Tumours showed in contrast to thrombosis marked enhancement after gadolinium injection, whereas the hydatid cyst and the lipomatosis demonstrated characteristic signal behaviour. Problems existed in differentiation mass vs slow flow, in the detection of very small masses, and in the assessment of wall-fixation and motion of a mass during cardiac cycle. The results demonstrate that MRI with Gd-DTPA can give important additional information in the differential diagnosis of echocardiographically detected intracardiac masses.

[Vascular kidney transplant rejection--is a duplex sonographic diagnosis possible?]. / Vaskuläre Nierentransplantatabstossung--Ist eine duplexsonographische Diagnose möglich?

The diagnostic value of quantitative Duplex Doppler sonography (DS) in renal allograft evaluation is being viewed increasingly critically. We undertook a retrospective analysis of DS in 51 consecutive patients to assess the capability of DS in the diagnosis of vascular rejection. At the time of renal allograft biopsy, a mean resistive index (RI) was calculated from Doppler measurements within main, segmental, interlobar and arcuate arteries and correlated with histological diagnosis. Our results indicate a low specificity (36% for RI greater than 0.7), low sensitivity (35% for RI greater than 0.9) as well as a low positive predictive value (54% for RI greater than 0.7) for the diagnosis of vascular rejection. Therefore, elevation of the RI is an unspecific finding in different causes of allograft dysfunction. Thus, renal biopsy to establish specific histologic diagnosis of allograft dysfunction remains mandatory.

[Bedside chest x-rays and extravascular lung water determination in intensive care patients]. / Die Thoraxbettaufnahme und extravaskuläre Lungenwasserbestimmung bei Intensivpatienten.

Radiological staging of pulmonary oedema was compared with the determination of extra-vascular lung water by means of a double indicator dilution technique. One hundred and forty-six ward chest radiographs were evaluated and compared with the results of simultaneous measurements of lung water. Seventy-seven cases could be evaluated statistically. Chest x-rays regarded as normal corresponded to extra-vascular lung water of 5 to 9 ml./kg. body weight. Interstitial oedema (radiological stage I and II) corresponded to extravascular lung water levels of 8 to 12 ml./kg. Differentiation of stages I and II was not possible. During stage III, extra-vascular lung water was 15 to 21 ml./kg. A comparative analyses of these findings revealed a discrepancy of 34%. The reasons for this are discussed.

[Diagnostic imaging of hemangiopericytomas]. / Bildgebende Diagnostik bei Hämangioperizytomen.

Eight patients with histologically verified hemangiopericytomas were examined by conventional radiographic techniques (plain films, angiography including cavography) as well as by duplex sonography, CT and MRI. These imaging techniques detected solid tumors with cystic compartments. A typical computed tomographic finding was intensive contrast enhancement within the tumor. Duplex sonography revealed blood flow in the periphery of the tumor. In contrast to reports by other authors no tumor calcification was found by plain film radiography.