Showing papers in "European Radiology in 1997"
TL;DR: Magnetic resonance colpocystctography (MR-CCRG) is presented in the evaluation of patients with pelvic-floor disorders as mentioned in this paper. But, it is not suitable for the diagnosis of enteroceles including a uterovaginal prolapse.
Abstract: Magnetic resonance colpocystorectography (MR-CCRG) is presented in the evaluation of patients with pelvic-floor disorders. Five healthy volunteers and 44 female patients with isolated or combined visceral descent underwent dynamic MRI and dynamic fluoroscopy (DF). MR-CCRG was performed with the patient in a supine position using a True FISP sequence (1 image/1.2 s; in-plane resolution 1.02 mm) during pelvic floor contraction, relaxation, and straining maneuvers. Relevant organs, such as urethra, bladder, vagina, and rectum, were opacified by using a saline solution, Magnevist (Schering AG, Berlin, Germany), and sonography gel, respectively. The clinical evaluation and the intraoperative results (30 cases) were used as reference. MR-CCRG and DF were non-diagnostic in 3 cases each. Most patients had a combined type of visceral prolapse, the most frequent combination being a vaginal vault prolapse and a cystocele. The points of reference were sufficiently outlined by DF and MR-CCRG. In comparison with the clinical and intraoperative results, MR-CCRG proved to be especially beneficial in the diagnosis of different types of enteroceles including a uterovaginal prolapse. MR-CCRG showed an equal or higher sensitivity and specificity for all individual sites when compared with DF. Also, predominant herniation obscuring other concomitant prolapse could be verified in 8 cases. MR-CCRG is superior to DF and accurately depicts pelvic-floor descent and prolapse in women. The possibility of dynamic presentation (see enclosed CD-ROM) allows for a better understanding of the organ movements within a given topographic reference setting.
279 citations
TL;DR: Examining variations in normal splenic size in relation to age, gender and body habitus in vivo, and to determine normative data for splenic volume on CT found that quantitative assessment of splenicVolume might be of value in assessing mild variations insplenic size.
Abstract: The purpose of our study was to examine variations in normal splenic size in relation to age, gender and body habitus in vivo, and to determine normative data for splenic volume on CT. The width (W), length (L), thickness (Th), cross-sectional areas and volume (Vol) of the spleen were obtained from abdominal CT examinations of 140 patients who underwent CT for indications unrelated to splenic disease. Splenic volume did not vary significantly (–0.04 0.10) with the patient's age, gender, height, weight, body mass index or the diameter of the first lumbar vertebra, the latter considered as representative of body habitus on CT. The mean value of the measured splenic volume (S Vol) was 214.6 cm3 with a range from 107.2 to 314.5 cm3. S Vol correlated well with all the linear and the maximal cross-sectional area measurements and could be calculated using the formula: S Vol = 30 + 0.58 (W × L × Th.). Employing the same formula splenic volume was reliably assessed in 47 patients with clinically evident splenomegaly. Quantitative assessment of splenic volume might be of value in assessing mild variations in splenic size, because splenomegaly is the most common manifestation of splenic involvement in many disorders.
238 citations
TL;DR: Initial clinical experience suggests that Gd-EOB-DTPA as a bolus injectable hepatobiliary MR contrast agent may offer useful features for the characterization of focal liver lesions by means of dynamic MR imaging.
Abstract: Our objective was to study Gd-EOB-DTPA for the characterization of focal liver lesions by means of dynamic MR imaging. A double-blind and randomized dose-ranging phase-2 clinical trial was performed in 31 patients (liver metastases n = 23, hepatocellular carcinoma n = 4, and hemangioma n = 4) at a field strength of 1.0 Tesla. Gd-EOB-DTPA (Schering AG, Berlin, Germany) was administered as an IV bolus (12.5, 25, or 50 μmol/kg body weight) with dynamic T1-weighted MRI during the distribution and cellular uptake of the contrast agent at multiple time points up to 45 min post contrast. Dynamic changes in tumor signal intensity, tumor–liver contrast, enhancement patterns, side effects, and adverse events were evaluated. Monitoring of vital signs revealed no significant changes during bolus injection of Gd-EOB-DTPA. Liver metastases demonstrated an inhomogeneous uptake of Gd-EOB-DTPA during the distribution phase with a washout effect on delayed images > 3 min and highest tumor–liver contrast 20 and 45 min post contrast. Hepatocellular carcinomas showed prolonged enhancement as compared with metastases and hemangiomas. Hemangiomas exhibited an early peripheral–nodular enhancement with subsequent partial or complete filling, persisting enhancement < 10 min following injection of Gd-EOB-DTPA, and delayed washout as compared with liver metastases. Initial clinical experience suggests that Gd-EOB-DTPA as a bolus injectable hepatobiliary MR contrast agent may offer useful features for the characterization of focal liver lesions.
174 citations
TL;DR: Evaluating the long-term results of percutaneous ethanol injection for the treatment of hepatocellular carcinoma (HCC) in patients with liver cirrhosis found long- term survival of cirrhotic patients with HCC treated with PEI is comparable to that reported in published series of matched patients submitted to surgical resection.
Abstract: The objective of our work was to evaluate the long-term results of percutaneous ethanol injection (PEI) for the treatment of hepatocellular carcinoma (HCC) in patients with liver cirrhosis. A total of 184 cirrhotic patients with HCC underwent PEI as the only anticancer treatment over an 8-year period. Patients were followed after therapy by means of clinical examinations, laboratory tests, and US and CT studies performed at regular time intervals. Survival rates were determined according to the Kaplan-Meier method. The overall survival was 67 % at 3 years, 41 % at 5 years, and 19 % at 7 years. The 3-, 5-, and 7-year survival rates of patients with single HCC ≤ 3 cm (78, 54, and 28 %, respectively) were significantly higher (p < 0.01) than those of patients with single HCC of 3.1–5 cm (61, 32, and 16, respectively) or multiple HCCs (51, 21, and 0 %, respectively). Survival of Child-Pugh A patients (79 % at 3 years, 53 % at 5 years, and 32 % at 7 years) was significantly longer (p < 0.01) than that of Child-Pugh B patients (50 % at 3 years, 28 % at 5 years, and 8 % at 7 years). A selected group of 70 patients with Child-Pugh A cirrhosis and single HCC ≤ 3 cm had a 7-year survival of 42 %. Long-term survival of cirrhotic patients with HCC treated with PEI is comparable to that reported in published series of matched patients submitted to surgical resection.
166 citations
TL;DR: Although MR imaging has an important role in the evaluation of breast lesions and, primarily, in ruling out malignancy, one should be aware of the fact that false-negative MR findings do occur.
Abstract: In this study we analyze MR-negative malignant lesions of the breast. A total of 204 patients with palpable and/or mammographic lesions were studied. The MR technique consisted of the turbo FLASH and MP-RAGE subtraction techniques. All patients underwent surgical biopsy and/or mastectomy and all specimens were examined by the correlative radiologic-histologic mapping technique. A total of 208 lesions were evaluated; 145 turned out to be malignant and 63 proved to be benign. Six malignant lesions were misinterpreted as benign on MR imaging; thus, suspicious contrast enhancement was present in 96 % of the lesions detected by mammography, US, or clinical examination. Especially 4 of the 17 ductal carcinoma in situ (DCIS) lesions were misinterpreted (23.5 %). Despite optimal technique, 6 malignant lesions were not identified by MR imaging. The highest prevalence of these MR occult lesions was in the group of DCIS. Although MR imaging has an important role in the evaluation of breast lesions and, primarily, in ruling out malignancy, one should be aware of the fact that false-negative MR findings do occur.
154 citations
TL;DR: After initial growth, spontaneous evolution of desmoids is characterized by shrinking and an increase in low-SI areas on T2-WI, which reveals that SI on T1-WI cannot be explained solely by cellularity.
Abstract: The objective of this study was to evaluate the appearance and the natural evolution of desmoid tumors on MR imaging, given histologic correlation. The MR images of 30 desmoids (20 primary and 10 recurrent) in 26 patients were scored for a multiplicity of morphological parameters, signal intensity (SI) on different pulse sequences, and behavior after contrast administration. Natural evolution was evaluated in 2 primary and 3 recurrent lesions, and correlated with evolution on histologic specimens. Desmoid tumors are mostly found in muscles of shoulder and hip girdle and are often fusiform with partially ill-defined margins. Rare subcutaneous desmoids have a more stellar morphology. Variable amounts of low-SI areas are present on all sequences. On T1-weighted images (T1-WI), most lesions are near homogeneous and isointense to muscle, whereas on T2-WI they are more heterogeneous with an overall SI equal to or slightly lower than fat. Histologic correlation reveals that SI on T2-WI cannot be explained solely by cellularity. After initial growth, spontaneous evolution of desmoids is characterized by shrinking and an increase in low-SI areas on T2-WI. While distal lesions shrink, the more recent lesions in asynchronous multicentric desmoids have a tendency to develop proximally in the same limb, and should not be confused with recurrences. Fast growth, extracompartmental spread, and bone involvement are often seen in recurrences. Follow-up MR imaging of desmoids indicates natural regression of desmoids and more aggressive behavior of recurrences, which may justify a more conservative therapeutic approach.
141 citations
TL;DR: A pulmonary arterial source of haemorrhage is uncommon but should always be considered in a patient who has further haemoptyses shortly after a technically successful embolization of bronchial and non-bronchial systemic arteries.
Abstract: Massive haemoptysis is defined as the expectoration of more than 600 mls of blood in 48 h. Many patients are not surgical candidates because of the presence of severe bilateral pulmonary disease and these individuals are best managed by bronchial artery embolization. Occlusion of both the bronchial arteries and hypertrophied non-bronchial systemic arteries is essential if bleeding is to be controlled. A pulmonary arterial source of haemorrhage is uncommon but should always be considered in a patient who has further haemoptyses shortly after a technically successful embolization of bronchial and non-bronchial systemic arteries. The immediate control of haemorrhage is achieved in the majority of patients although subsequent rebleeding on longterm follow-up is not uncommon.
112 citations
TL;DR: Ultrasound, which is a non-invasive, portable and even bedside imaging procedure, appears accurate in confirming a SB obstruction and in determining the aetiology of SB obstruction.
Abstract: The purpose of this study was to determine whether sonography provides additional clinical information in patients suspected of small bowel (SB) obstruction. During a period of 30 months, in a prospective setting, we evaluated with sonography 123 patients suspected of SB obstruction. Sonographic examinations of the entire abdomen were performed with state-of-the-art, real-time, grey-scale equipment. Fourteen patients were labelled ’gassy' and no added information was provided following abdominal ultrasound. Sonography confirmed the SB obstruction in 82 cases with 5 false positives, resulting in a specificity of 82.1 %. Sonographic examinations were negative in 27 cases with 4 false negatives and a sensitivity of 95 %. The accuracy was 91.7 % when the ’gassy' patients were excluded and 81.3 % overall. The aetiology of the ileus was detected by sonography in 13 cases of paralytic ileus (54.1 %) and in 57 cases of mechanical ileus (71.4 %). It is concluded that ultrasound, which is a non-invasive, portable and even bedside imaging procedure, appears accurate in confirming a SB obstruction and in determining the aetiology of SB obstruction.
105 citations
TL;DR: The purpose of this essay is to illustrate the use of CT in depicting some unusual locations of HD besides the liver and lung.
Abstract: Hydatid disease (HD), already known by Hippocrates, is prevalent and widespread in most sheep-raising countries in Asia, Australia, South America, Near East, and southern Europe. The disease is most commonly due to Echinococcus granulosus and may occur in any organ or tissue. The location is mostly hepatic (75 %) and pulmonary (15 %), and only 10 % occur in the rest of the body [1]. Imaging modalities such as US, CT, and MR imaging are helpful in diagnosing the disease. The reliability of each method depends on the cyst's location in the body [2-5]. The purpose of this essay is to illustrate the use of CT in depicting some unusual locations of HD besides the liver and lung.
102 citations
TL;DR: The maturation time of myometrial scar tissue in uncomplicated cesarean sections, which can be evaluated by the signal alterations in MRI, is approximately 3 months, whereas the complete involution and the recovery of the zonal anatomy need at least 6 months.
Abstract: The purpose of this study was to examine the healing period of incision scar in myometrial wall and the normal pelvis after cesarean sections by means of MRI. In this study 17 voluntary women were examined after their first delivery with cesarean section in the early postpartum period (first 5 days), and following this, three more times in 3-month intervals. The MRI examinations were performed on a 1.0-T system (Magnetom, Siemens, Erlangen, Germany), and sagittal T1-weighted (550/17 TR/TE) and T2-weighted (2000/80 TR/TE) spin-echo (SE) images of the pelvis were obtained. During follow-up examinations incision scar tissues lost their signals within the first 3 months on both SE sequences, and little alteration was observed in the subsequent tests. Zonal anatomy of the uterus reappeared completely 6 months after cesarean sections. The time for the involution of the uterus was independent of the zonal anatomy recovery, and the maximum involution was inspected within the first 3 months. In conclusion, the maturation time of myometrial scar tissue in uncomplicated cesarean sections, which can be evaluated by the signal alterations in MRI, is approximately 3 months, whereas the complete involution and the recovery of the zonal anatomy need at least 6 months.
101 citations
TL;DR: Catheter thrombolysis of iliofemoral vein thrombosis revealed many anatomical abnormalities which may predispose to thromBosis and are often amenable to stenting.
Abstract: The aim of our study was to evaluate the results of catheter-directed thrombolysis and complementary procedures to treat acute iliofemoral deep vein thrombosis (DVT). A total of 24 consecutive patients with acute iliofemoral DVT underwent intrathrombus drip infusion of alteplase (3 mg/h; mean dosage 86 mg, range 45–174 mg), while intravenous heparin (1000 U/h) was continued. Complementary procedures were hydrodynamic thrombectomy in 3 and primary insertion of a Wallstent in 9 patients. Patency of 19 thrombosed veins (79 %) was restored with prompt symptomatic relief. An underlying anatomical anomaly or lesion was present in 13 patients: iliac vein compression syndrome (n = 8), absent (n = 2) or obstructed (n = 1) vena cava or venous stenosis (n = 2). Ten of the abnormalities were unknown before lysis and eight were relieved by stent deployment. Puncture site bleeding was the only complication but led to transfusion in 6 patients (25 %). Symptomatic reocclusion occurred in 4 patients. Catheter thrombolysis of iliofemoral vein thrombosis revealed many anatomical abnormalities which may predispose to thrombosis and are often amenable to stenting.
TL;DR: Wegener's granulomatosis should be included in the differential diagnosis of patients with low-signal-intensity lesions on T1- and T2-weighted SE sequences of the nasal cavity, paranasal sinuses and orbits, according to diagnostic MRI criteria.
Abstract: The purpose of this study was to evaluate diagnostic MRI criteria in Wegener's granulomatosis of the nasal cavity, the paranasal sinuses and orbits Between March 1991 and January 1996, 62 patients with biopsy-proven Wegener's granulomatosis were studied with T1- and T2-weighted spin-echo (SE) sequences In 32 patients coronal postcontrast T1-weighted images were obtained Mucosal thickening of the nasal cavity and paranasal sinuses was demonstrated as high-intensity lesions on T2-weighted SE sequences in 57 patients (92 %) Of this group, inflammatory granulomatous tissue was found on biopsy in 30 patients (48 %) in the nasal cavity and in 4 patients (6 %) in the paranasal sinuses In 23 patients (37 %) biopsy revealed unspecific inflammatory changes without evidence of granulomatous tissue In 14 patients (23 %) granulomas were depicted as low-signal intensity lesions on T1- and T2-weighted SE sequences in the paranasal sinuses and orbits In 5 patients (8 %) osseous destruction was found After gadolinium injection, 12 of 14 granulomas showed inhomogeneous signal enhancement In two granulomas no enhancement was found The MRI technique is helpful in the diagnosis of patients with Wegener's granulomatosis In the initial inflammatory process of Wegener's granulomatosis, it is not possible to differentiate between mucosal inflammation and granulomatous tissue in MRI In the later stage of granulomatous transformation, granulomas can be depicted as low-signal-intensity lesions Therefore, Wegener's granulomatosis should be included in the differential diagnosis of patients with low-signal-intensity lesions on T1- and T2-weighted SE sequences of the nasal cavity, paranasal sinuses and orbits
TL;DR: Radiation risk must always be viewed in context with disease- and therapy-related risks and balanced against the benefit of the diagnostic examination, which should always exceed the risk for a well-indicated procedure.
Abstract: The exposure of the German population to man-made radiation results mainly from diagnostic X-ray and nuclear medical examinations. Data are presented about the annual frequency and the average dose of the various examination types for West Germany in the years 1990-1992. According to these data a yearly average of approximately 1550 diagnostic examinations using ionizing radiation were performed per 1000 inhabitants resulting in an annual per caput effective dose of 1.9 mSv. Despite the frequent use of alternative examination techniques, such as sonography, nuclear magnetic resonance and endoscopy, the frequency of X-ray and nuclear medical examinations is still increasing. If collective risk assessments are done using the per caput effective dose, at least the age distribution of the patients must be considered. This leads to a "risk-modifying factor" of 0.6-0.7 for patients to be applied to the ICRP risk coefficient of 5 % per Sv valid for the general population. However, radiation risk must always be viewed in context with disease- and therapy-related risks and balanced against the benefit of the diagnostic examination, which should always exceed the risk for a well-indicated procedure.
TL;DR: Ultrasound is presently the only means to prevent an unnecessary operation for this condition which is principally self-limiting and innocuous, and its incidence at this moment is grossly underestimated.
Abstract: Yersinia, Campylobacter, and Salmonella are pathological microorganisms which incidentally may specifically infect the ileocecal area (infectious ileocecitis). In such cases pain in the right lower quadrant is the predominant symptom, and diarrhea is absent or only mild. This symptomatology can lead to an unnecessary laparotomy for suspected appendicitis. At surgery a normal appendix is removed, while there is edematous thickening of ileum and cecum, and enlarged mesenteric lymph nodes. These ileocecal abnormalities give rise to a fairly characteristic US image, enabling the radiologist to rapidly differentiate infectious ileocecitis from appendicitis, thus preventing an unnecessary laparotomy. Infectious ileocecitis caused by Yersinia, Campylobacter, and Salmonella is a common mimicker of appendicitis, and its incidence at this moment is grossly underestimated. Ultrasound is presently the only means to prevent an unnecessary operation for this condition which is principally self-limiting and innocuous.
TL;DR: Evaluating the appearance of localized giant cell tumour of the tendon sheath on unenhanced and Gd-enhanced MR images concludes that these characteristic MR features are a valuable diagnostic tool in offering a correct preoperative diagnosis.
Abstract: The objective of this study was to evaluate the appearance of localized giant cell tumour of the tendon sheath (GCTTS) on unenhanced and Gd-enhanced MR images. MR images of 13 histologically proven cases of localized GCTTS were evaluated for mean size, location, homogeneity and signal intensity (SI) on both T1- and T2-weighted images, and enhancement pattern. All lesions except 1 affected young adults. On T1- and T2-weighted images, lesions showed predominantly low SI equal to or slightly higher than skeletal muscle. On Gd-enhanced T1-weighted images, strong homogeneous enhancement was seen. These findings reflect the underlying histological composition of the lesion; haemosiderin deposition in xanthoma cells, shortening T2-relaxation time, and abundant collagenous proliferation are responsible for low SI on T1- and T2-weighted images. Strong homogeneous enhancement originates from numerous proliferative capillaries in the collagenous stroma. We conclude that these characteristic MR features, together with clinical information, are a valuable diagnostic tool in offering a correct preoperative diagnosis.
TL;DR: It is concluded that MRI and US are both sensitive in detection of abnormalities of the rotator cuff and should be the primary diagnostic method in screening of shoulder pain because it is economic and fast.
Abstract: An experimental study was performed on cadaveric joint specimens of the shoulder to determine the accuracy of US and MRI in diagnosis of abnormalities of the rotator cuff. The value of different morphological criteria was evaluated for discrimination of degeneration as well as partial and complete disruption. A total of 38 surgically exposed specimens of the shoulder joint were examined by US, MRI and pathological methods visualising the tendons of the rotator cuff in same axial and longitudinal orientations. The three imaging modalities were reviewed separately by experienced examiners, respectively, who were blind to other results. Evaluation criteria consisted of signs of shape (thinning, thickening, discontinuity and absence of rotator cuff) and structure (changes in echogenicity in US, increased signal intensity in MRI, tissue changes in pathology). Findings in US and MRI were finally compared with pathology to assess sensitivity and specificity. Pathology demonstrated 4 full-thickness tears, 6 partial-thickness tears, 16 cases with degeneration and 12 normal rotator cuffs. Ultrasound showed pathological signs in all abnormal cuffs, and one MRI report was false negative. Specificity was 67 % in US (4 of 12 cases were false positive) and 100 % in MRI (no abnormal findings in healthy tendons). Discrimination of different pathological disorders of the rotator cuff was reduced in both methods. Using US only 10 of 16 cases of degeneration, 2 of 6 partial tears and 3 of 4 complete tears were correctly defined. Using MRI 13 of 16 degenerations, 3 of 6 partial tears and 3 of 4 complete tears were detected. The MRI technique failed to visualise intratendinous calcifications in all 3 cases. We conclude that MRI and US are both sensitive in detection of abnormalities of the rotator cuff. Ultrasound should be the primary diagnostic method in screening of shoulder pain because it is economic and fast. The MRI technique should be used secondary because it provides more information about extent of tendons and has lower risk of artefacts.
TL;DR: The MRI criteria may be helpful in the diagnosis of Arrhythmogenic right ventricular dysplasia and may be effective in the assessment of ARVD.
Abstract: Arrhythmogenic right ventricular dysplasia (ARVD) is a heart disease characterized by a total or partial fat replacement of the myocardium. A total of 30 patients were studied with a suspected diagnosis of ARVD. Clinical criteria used for evaluation of ARVD were: (a) ventricular origin arrhythmias with a left bundle branch block configuration, (b) T-wave inversion in the anterior precordial leads, (c) ventricular kinetic alterations observed using echocardiography and angiography and (d) cardiac failure when there are no pathologies attributable to other heart diseases. All patients had serial EKG and echocardiography tests. One third of patients underwent angiocardiography; 7 of 30 had Holter; 7 of 30 had exercise test just to evaluate the effectiveness of the anti-arrhythmic therapy. All patients underwent MRI examination. The following MRI criteria were used: (a) high-intensity areas indicating the fatty substitution of the myocardium, (b) ectasia of the right ventricular outflow tract, (c) dyskinetic bulges, (d) dilation of the right ventricle and (e) enlargement of the right atrium. The diagnosis of ARVD was classified as highly probable for patients manifesting at least three positive criteria, probable with two positive criteria, dubious with one and negative in the absence of all criteria. Highly probable diagnosis of ARVD was made in 8 patients, probable in 4, dubious in 7 and negative in 11. The MRI technique is very effective in the assessment of ARVD. The MRI criteria may be helpful in the diagnosis of this condition.
TL;DR: The signal behavior of contrast-enhanced MR mammography is not related to established histopathological prognostic parameters as subtyping, grading, nodal status, and the expression of certain oncogenes/tumor suppressor genes.
Abstract: The objective of this study was to evaluate the prognostic value of contrast-enhanced MR mammography in patients with breast cancer. A total of 190 patients with breast cancer (37 noninvasive carcinomas, 153 invasive carcinomas) underwent dynamic contrast-enhanced MR mammography preoperatively. Using 1.5-T unit, T1-weighted sequences (2D FLASH) were obtained repeatedly one time before and five times after IV administration of 0.1 mmol gadopentetate-dimeglumine per kilogram body weight. The findings on MR imaging were correlated with histopathologically defined prognostic factors (histological type, tumor size, tumor grading, metastasis in lymph nodes). In addition, immunohistochemically defined prognostic factors (c-erbB-1, c-erbB-2, p53, Ki-67) were correlated with the signal increase on MR mammogram in 40 patients. There was no significant correlation between the findings on MR mammography and the histopathological type of carcinoma, the grading, and the lymphonodular status. Noninvasive carcinomas showed a higher rate of moderate (38 %) or low (27 %) enhancement on MR imaging than invasive carcinomas (6 and 3 %). The results on MR mammography and the results of immunohistochemical stainings did not correlate significantly. Noninvasive carcinomas showed significantly lower enhancement than invasive carcinomas. However, the signal behavior of contrast-enhanced MR mammography is not related to established histopathological prognostic parameters as subtyping, grading, nodal status, and the expression of certain oncogenes/tumor suppressor genes.
TL;DR: Investigation of the time course of contrast enhancement in bile ducts and the gallbladder after injection of gadolinium-ethoxybenzyl-DTPA found hyperintense visualization of normal extrahepatic biles ducts as well as the GB is regularly achieved with the hepatobiliary contrast agent Gd-EOB- DTPA.
Abstract: The purpose of this study was to investigate the time course of contrast enhancement in bile ducts and the gallbladder (GB) after injection of gadolinium-ethoxybenzyl-DTPA (Gd-EOB-DTPA). In a clinical phase-I study, MR imaging at 1.5T was performed in 16 healthy volunteers with four different doses of Gd-EOB-DTPA (10, 25, 50, and 100 micro;mol/kg b. w., four volunteers per dosage). The study protocol comprised a heavily T1-weighted fast multiplanar gradient-echo (GE) sequence before and at increasing intervals for up to 360 min after injection of Gd-EOB-DTPA. The signal enhancement was evaluated in extra- and intrahepatic bile ducts as well as in the GB. In all 16 volunteers the common bile duct showed intense signal enhancement beginning 5-16 min after injection (mean 10 min) and persisting for at least 120 min in 4 subjects and for 360 min in 12 subjects. The duration of signal enhancement was significantly (p < 0.05) longer for higher doses (50, 100 micro;mol/kg) than for lower doses (10, 25 micro;mol/kg). Intrahepatic bile ducts were hyperintense as compared with liver parenchyma in all subjects receiving 10 micro;mol/kg from approximately 50-120 min after contrast agent application. Intrahepatic bile ducts were not displayed using the higher doses, probably because of the strong enhancement of the liver parenchyma. Gallbladder contrasting was achieved in all cases beginning 7-33 min after injection (mean 19 min) and remained visible for up to 360 min in 94 %. Hyperintense visualization of normal extrahepatic bile ducts as well as the GB is regularly achieved with the hepatobiliary contrast agent Gd-EOB-DTPA. The dosage for hyperintense visualization of intrahepatic bile ducts is 10 micromol/kg.
TL;DR: The limitations of gray-scale US in the assessment of an acute scrotum and in particular of testicular torsion have now been overcome by color-coded duplex sonography and power Doppler.
Abstract: Ultrasound is the mainstay for imaging of the scrotum. It is used primarily for determining the location and nature of palpable lesions and to demonstrate nonpalpable lesions. Scrotal US is characterized by high sensitivity in the detection of intrascrotal abnormalities and is a very good mode for differentiating testicular from paratesticular lesions. However, scrotal US is limited in determining whether a focal testicular lesion is benign or malignant. The limitations of gray-scale US in the assessment of an acute scrotum and in particular of testicular torsion have now been overcome by color-coded duplex sonography and power Doppler.
TL;DR: Reduced bone mass is a useful predictor of increased fracture risk and therefore bone mineral density (BMD) is the single most important determinant as to whether or not a fracture occurs.
Abstract: Osteoporosis is the most common of the metabolic disorders of bone. The condition is characterised by reduced bone mass and easy (fragility) fracture. Such fractures can occur in any site but are most frequent in the wrist, spine (vertebral body) and hip — areas of the skeleton rich in trabecular bone. Such fractures, and particularly those in the hip, result in considerable morbidity (pain, deformity, loss of height with vertebral fractures) and even mortality, with enormous socio-economic consequences. Treatment of established osteoporosis is difficult and often unsatisfactory, although in recent years diphosphonates (etidronate, alendronate) have been introduced which show encouraging results in increasing bone mass and reducing fracture incidence [1, 2]. Previously treatment strategies favoured prevention of osteoporosis by maximising peak bone mass, minimising age related and postmenopausal bone loss (hormone replacement therapy), avoiding risk factors, and ensuring adequate dietary intake of calcium and appropriate exercise. There is a growing demand from patients, general medical practitioners and specialists (obstetricians, orthopaedic surgeons, rheumatologists and endocrinologists) for clinical services that provide for the detection, assessment and management of osteoporosis [3, 4]. Whether a fracture is sustained depends on a variety of factors including the propensity to fall and the response to falling [5, 6]. However, bone mineral density (BMD) is the single most important determinant as to whether or not a fracture occurs [7,8] (Fig. 15-1). Reduced bone mass is therefore a useful predictor of increased fracture risk [9–11].
TL;DR: Power Doppler imaging is superior to conventional color doppler sonography in the depiction of the intratumoral flow characteristics of HCA and FNH, and enables a more accurate differential diagnosis than color Dopplers sonography.
Abstract: The aim of our study was to compare the diagnostic efficacy of power Doppler imaging and conventional color Doppler sonography for differentiating between hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) of the liver. Thirty-one focal liver lesions (in 29 patients) with histologic proof of HCA (n = 9) or FNH (n = 22) were studied with power and color Doppler sonography according to a standardized examination protocol. The size of the lesions ranged between 1.5 and 14.5 cm (HCA, 3.5-14.5 cm, mean +/- SD 7.3 +/- 3.3 cm; FNH, 1.5-9.1 cm, mean +/- SD 5.1 +/- 2.1 cm). Intratumoral vessels with a venous Doppler spectrum, associated with either pulsatile or continuous peripheral flow, were detected in HCA (eight of nine lesions by power Doppler imaging and six of nine by color Doppler imaging) but not in FNH. In contrast, color signals with an arterial Doppler spectrum, radiating from the center to the periphery of the lesion, were depicted in FNH (20 of 22 cases by power Doppler imaging and 15 of 22 by color Doppler sonography) but not in HCA. Differentiation of HCA and FNH was achieved in 28 of 31 cases (90 %) by power Doppler imaging and in 21 of 31 (68 %) by color Doppler sonography (p < 0.01). Power Doppler imaging is superior to conventional color Doppler sonography in the depiction of the intratumoral flow characteristics of HCA and FNH, and enables a more accurate differential diagnosis than color Doppler sonography.
TL;DR: Radiological findings should be carefully correlated with clinical features such as patient age, family history, symptoms, physical findings, and renal functional status before a diagnosis is attempted.
Abstract: Renal cystic disease comprises a mixed group of heritable, developmental, and acquired disorders. Because of their diverse etiology, histology, and clinical presentation, no single scheme of classification has gained acceptance. Conditions include autosomal dominant polycystic kidney disease, acquired renal cystic disease, medullary sponge kidney, autosomal recessive polycystic kidney disease, multicystic dysplastic kidney, medullary cystic disease, tuberous sclerosis, cysts of the renal sinus, and von Hippel-Lindau's disease. An awareness of the pathology of each cystic disease is helpful in the understanding of the corresponding radiological images. Imaging techniques used in evaluating renal cystic disease include intravenous urography, sonography, CT, MRI, nuclear medicine, and renal angiography. Many types of cystic disease show similar imaging features. Meticulous attention to subtle radiological findings is therefore essential for reaching a correct diagnosis. Imaging features requiring analysis include whether the cysts are unilateral or bilateral, renal size and functional status, cyst distribution in the kidneys, and the presence of hemorrhagic and calcified renal cysts, solid renal masses, renal sinus cysts, and cysts in adjacent organs. Radiological findings should be carefully correlated with clinical features such as patient age, family history, symptoms, physical findings, and renal functional status before a diagnosis is attempted.
TL;DR: Simulations of the inner walls of the airways were of good quality in 27 of 29 patients and evaluation of the length of stenoses and surrounding tissues required simultaneous display of multiplanar reformations, providing a valuable road map for bronchoscopy, in an image format familiar to bronchoscopeists.
Abstract: The purpose of this study was to determine the feasibility of using virtual bronchoscopy simulations to depict stenoses of the tracheobronchial tree. Virtual bronchoscopy simulations, based on ray casting, were applied to spiral-CT data sets of 29 patients presenting 41 stenoses of the central airways, proved with fiberoptic bronchoscopy. Simulations of the inner walls of the airways were of good quality in 27 of 29 patients. Airway stenoses were depicted in 39 of 41 cases. Evaluation of the length of stenoses and surrounding tissues required simultaneous display of multiplanar reformations. Virtual bronchoscopy provides a valuable road map for bronchoscopy, in an image format familiar to bronchoscopists.
TL;DR: ProHance remains today still the only commercial MRI agent that is both macrocyclic and nonionic, and to date it has been used safely in over a million patients.
Abstract: The four gadolinium chelates currently in clinical use as magnetic resonance imaging (MRI) contrast agents differ in two structural features: linear vs macrocyclic cores, and ionic vs nonionic charge types While all are equivalent in relaxation effectiveness, the nonionic molecules have lower osmolality and viscosity and may be formulated safely at greater concentrations, and delivered confidently at greater doses and as a faster bolus The macrocyclic molecules are more stable and show less tendency to dissociate free Gd ProHance was conceived well over a decade ago, based upon a unique structure It was first marketed in the USA in 1992, and was the first nonionic agent It remains today still the only commercial MRI agent that is both macrocyclic and nonionic To date it has been used safely in over a million patients
TL;DR: Magnetic resonance imaging (MRI) of the breast brings the advantages of high resolution cross-sectional imaging to breast cancer diagnosis, treatment and research: improved cancer detection, staging, selection of therapy, evaluation of therapeutic response in vivo, detection of recurrence, and even the development of new therapies.
Abstract: Magnetic resonance imaging (MRI) of the breast brings the advantages of high resolution cross-sectional imaging to breast cancer diagnosis, treatment and research: improved cancer detection, staging, selection of therapy, evaluation of therapeutic response in vivo, detection of recurrence, and even the development of new therapies. Until now breast cancer treatment and research has been impeded by the limited means of evaluating the breast cancer in vivo: primarily clinical palpation and mammography of the breast tumor. A review of the initial studies shows that with the use of paramagnetic contrast agents, MRI has a sensitivity of 96 % for detecting breast cancers. MRI detects multicentric disease with a sensitivity of 98 %, superior to any other modality. The ability of MRI to detect recurrent local breast cancer in the conservatively treated breast is nearly 100 %. MRI is capable of monitoring tumor response to chemotherapy and actually guiding therapeutic interventions such as interstitial laser photocoagulation.
TL;DR: A positive CT finding of abdominal wall hernia is reliable, while a negative finding does not exclude the diagnosis, and the interobserver variation of the CT diagnoses is acceptable.
Abstract: The aim of the study was to estimate the value of CT in the diagnosis of abdominal wall hernias and at the same time to create a standard for this CT investigation. Twenty-four patients with suspected hernia of the abdominal wall were examined. All were operated on. The CT scans were assessed by two radiologists to estimate the interobserver variation. The CT diagnoses made by the two radiologists were correct in 83 % and 79 % of cases, respectively. The sensitivity was 0.83 in both CT evaluations and the specificity was 0.83 and 0.67, respectively. The predictive value of a positive CT finding was 0.94 and 0.88, while the predictive value of a negative CT finding was 0.63 and 0.57, respectively. The interobserver variation (kappa) was 0.87. The study therefore indicates that a positive CT finding of abdominal wall hernia is reliable, while a negative finding does not exclude the diagnosis. The interobserver variation of the CT diagnoses is acceptable. To achieve the highest diagnostic accuracy, it is recommended to always use the Valsalva manoeuvre, oral intake of contrast and 10/10 mm CT slices.
TL;DR: Because MRCP provides sufficient diagnostic information in a wide range of benign and malignant biliary and pancreatic disorders, it could obviate diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in many clinical settings.
Abstract: The objective of this article is to review technical aspects, discuss potential clinical indications for MR cholangiopancreatography (MRCP) and demonstrate the spectrum of diagnostic findings in benign, postoperative, and malignant conditions. We describe our current imaging protocol in comparison with other available techniques. Using a non-breath-hold, heavily T2-weighted fast-spin-echo (FSE) sequence with or without respiratory gating we obtained coronal and axial source images and maximum intensity projections (MIPs) in 102 patients with suspected abnormalities of the biliary or pancreatic ducts. Based on this series we demonstrate the diagnostic appearance of a variety of benign, postoperative, and malignant conditions of the biliary and pancreatic ducts and discuss potential clinical indications for MRCP. The non-breath-hold FSE technique enables a consistent image quality even in patients who cannot cooperate well. Respiratory gating increased the rate of diagnostic examinations from 79 to 95 %. Acquisition of coronal and axial source images enables detection of bile duct stones as small as 2 mm, although calculi that are impacted and not surrounded by hyperintense bile may sometimes be difficult to detect. The MIP reconstructions help to determine the level of obstruction in malignant jaundice, delineate anatomical variants and malformations, and to diagnose inflammatory conditions, e. g., sclerosing cholangitis, the Mirizzi syndrome and inflammatory changes in the main pancreatic duct. The MRCP technique also correctly demonstrates the morphology of bilio-enteric or bilio-biliary anastomoses. Because MRCP provides sufficient diagnostic information in a wide range of benign and malignant biliary and pancreatic disorders, it could obviate diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in many clinical settings. The ERCP technique may be increasingly reserved for patients in whom nonsurgical interventional procedures are anticipated.
TL;DR: The technical aspects of contrast-enhanced 3D MRA are described, existing and potential future clinical applications are reviewed, and the prospect of extending clinical indications of MRI to diseases affecting other vascular structures of the thorax is reviewed.
Abstract: Magnetic resonance angiography (MRA) has become a useful non-invasive imaging technique for the assessment of vascular disease. Due to limitations such as respiratory motion artefacts, saturations problems, and long acquisition times, applications of MRA in the thorax have largely been restricted to imaging of the aorta. The recent introduction of breath-hold three-dimensional (3D) contrast-enhanced MRA promises not only to enhance conventional MR protocols for aortic imaging, but to extend the clinical indications of MRI to diseases affecting other vascular structures of the thorax, most notably the pulmonary arteries. This article describes the technical aspects of contrast-enhanced 3D MRA and reviews existing and potential future clinical applications.
TL;DR: Iiopathic herniation of the spinal cord is an extremely rare disorder which may cause progressive myelopathy and CT myelography using thin slice sections is useful in the diagnosis of this disease.
Abstract: Idiopathic herniation of the spinal cord is an extremely rare disorder which may cause progressive myelopathy. Two cases of this entity reported herein were both examined using MRI and CT myelography. The typical appearance of this disease with or without a dorsal intradural arachnoid cyst is focal ventral displacement of the mid-thoracic spinal cord, mimicking an isolated intradural spinal arachnoid cyst on MRI. CT myelography using thin slice sections is useful in the diagnosis of this disease.