[Diagnostic image (91). A collapsing man with an aortic aneurysm. Ruptured aneurysm of the abdominal aorta]. / Diagnose in beeld (91). Een gecollabeerde man, bekend wegens een aorta-aneurysma. Gebarsten aneurysma aortae abdominalis.

A 73-year-old man had been diagnosed with an abdominal aortic aneurysm. Surgery was impossible due to poor cardiopulmonary condition. The patient collapsed due to rupture of the aneurysm.

A rational approach to dose reduction in CT: individualized scan protocols.

The aim of this study was to demonstrate that dose reduction and constant image quality can be achieved by adjusting X-ray dose to patient size. To establish the relation between patient size, image quality and dose we scanned 19 patients with reduced dose. Image noise was measured. Four radiologists scored image quality subjectively, whereby a higher score meant less image quality. A reference patient diameter was determined for which the dose was just sufficient. Then 22 patients were scanned with the X-ray dose adjusted to their size. Again, image noise was measured and subjective image quality was scored. The dose reduction compared with the standard protocol was calculated. In the first group the measured noise was correlated to the patient diameter (rho=0.78). This correlation is lost in the second group (rho=-0.13). The correlation between patient diameter and subjective image quality scores changes from rho=0.60 (group 1) to rho=-0.69 (group 2). Compared with the standard protocol, the dose was reduced (mean 28%, range 0-76%) in 19 of 22 patients (86%). Dose reduction and constant noise can be achieved when the X-ray dose is adjusted to the patient diameter. With constant image noise the subjective image quality increases with larger patients.

[Diagnostic image (60) Chilaiditi syndrome]. / Diagnose in beeld (60). Syndroom van Chilaiditi.

In a 27-year-old man in whom an X-ray of the thorax was made, Chilaiditi syndrome (interposition of the colon between diaphragm and the liver) was diagnosed.

[Diagnostic image(58). Renal cell carcinoma]. / Diagnose in beeld (58). Niercelcarcinoom.

In a 38-year-old man with flank pain and macroscopic haematuria, CT revealed a renal mass of which the pathology diagnosis was: primary renal cell carcinoma.

Von Hippel-Lindau disease: strategies in early detection (renal-, adrenal-, pancreatic masses).

Von Hippel-Lindau disease (VHL) is a hereditary syndrome characterized by a predisposition for bilateral and multicentric retinal angiomas, hemangioblastomas in the central nervous system (CNS), renal cell carcinomas, pheochromocytomas, islet cell tumors of the pancreas, and endolymphatic sac tumors, as well as cysts in the kidney, pancreas, and epididymis. This review focuses on developments in imaging of renal, adrenal, and pancreatic masses in VHL. Radiology still has a central place in managing of VHL. Radiologists should therefore be aware of the importances of MRI, CT, and US compared with other radiodiagnostic tools for these three organs. Since a conservative approach to the treatment of VHL lesions is now becoming more widely accepted, ongoing follow-up by careful radiological screening with US, and especially with MRI, will play a central role in managing the disease. We also give an overview of recent advances in the molecular biology of VHL, because the combination of imaging with (presymptomatic) DNA analysis has made early detection and screening of lesions possible and led to a reduction in morbidity and mortality.

Management of renal cell carcinoma in von Hippel-Lindau disease.

BACKGROUND: An evaluation of nephron-sparing surgery (NSS) or radical nephrectomy (RN) for treating renal cell carcinoma (RCC) in patients with von Hippel-Lindau disease (VHL) was carried out. METHODS: Between 1976 and 1997, 10 patients with RCC from four VHL families, of whom seven were from one family, were studied by clinical and histopathological examination. Before 1991, three patients were treated using RN, and thereafter five patients were treated using NSS. Two patients were not operated on. RESULTS: RCCs in our patients showed a slow growth rate (on average 0.3 cm year-1), and asymptomatic patients presented with tumours of low-grade malignancy. In all patients, tumours were surrounded by a fibrous pseudocapsule. In 5 out of 17 tumours, pseudocapsular invasion was observed, and three of these five tumours broke through the pseudocapsule. To date, these patients have not shown a less favourable outcome than those without pseudocapsular involvement by tumour growth. Multicentricity of RCC was relatively low (4.6 lesions per kidney). In two of the three RN patients, only a single satellite lesion, in the direct vicinity of a RCC, was found in one kidney. Six tumours (1.8-5.5 cm) were enucleated by NSS. During a mean follow-up of 30 months, renal function in these patients was well preserved. CONCLUSIONS: In our patients, RCCs grew slowly, were of low grade, had a dense fibrous pseudocapsule and were thus good candidates for NSS.

Added value of CT criteria compared to the clinical SAP score in patients with acute pancreatitis.

BACKGROUND: To assess the added value of established computed tomography (CT) scores versus the Simplified Acute Physiology (SAP) score in predicting outcome in patients with acute pancreatitis. METHODS: Contrast-enhanced CT was performed in 45 patients with acute pancreatitis. The Balthazar score, CT severity index (CTSI), and Schröder score were assessed, and the SAP score was calculated. The predictive values of CT score and SAP score for mortality, need for one or more interventions, and length of hospital stay were compared. The added value of the SAP score to the CT scores was assessed by using ROC (receiver operating curve) analysis. RESULTS: The positive predictive values of the higher Balthazar, CTSI, Schröder, and SAP scores, reflecting severe disease, were 50%, 41%, 41%, and 48%, respectively, for mortality, 85%, 84%, 84%, and 83%, respectively, for need for one or more interventions, and 55%, 66%, 66%, and 65%, respectively, for longer hospital stay. The negative predictive values of the lower Balthazar, CTSI, Schröder and SAP scores were 84%, 92%, 92%, and 42%, respectively, for mortality, 44%, 69%, 69%, and 45%, respectively, for need for one or more interventions, and 44%, 69%, 69%, and 55%, respectively, for longer hospital stay. When CT scores were added to the SAP score, there was no improvement in discriminating power for mortality. CONCLUSION: To identify patients with severe outcome, there is no clear benefit using established CT scores as opposed to the SAP score. However, the Balthazar score and CTSI are better than the SAP score in predicting a favorable outcome.

Digital chest imaging using a selenium detector. The impact of hard copy size on observer performance: a computed tomography-controlled study.

RATIONALE AND OBJECTIVES: The authors compare radiologist detection performance under clinical conditions for assessment of the effect of size reduction on the diagnostic performance of digital chest images obtained with a selenium detector. METHODS: Sixty-five patients were examined with the digital system. The images were acquired without an antiscatter grid. Sixty-five posteroanterior life-size images (35 x 43 cm) and sixty-five posteroanterior minified images (56% of life size) were analyzed by three observers for detection of pulmonary, mediastinal, and pleural pathology, using computed tomography as the reference standard. The diagnostic value of life-size and minified images for the detection of these chest abnormalities was analyzed with receiver operating characteristic (ROC) methods. RESULTS: For the detection of the various abnormalities by all radiologists, the areas under the ROC curves with life-size images versus minified images, respectively, were as follows: pulmonary opacities, 0.78 versus 0.78; interstitial disease, 0.74 versus 0.75; mediastinal disease, 0.70 versus 0.72; and pleural abnormalities 0.72 versus 0.67. CONCLUSIONS: There was no statistically significant difference between the radiologists' performance in detecting pulmonary, mediastinal, and pleural pathology with life-size versus that with minified (56% of life size) digital selenium chest radiography.

Radiation-induced brachial plexopathy: MR imaging.

OBJECTIVE: To describe the MR imaging appearance of radiation-induced brachial plexopathy. DESIGN: MR imaging was performed in two patients with the clinical diagnosis of radiation-induced brachial plexopathy and in one with surgically proven radiation fibrosis of the brachial plexus. PATIENTS: Three patients who had had radiation therapy to the axilla and supraclavicular region (two with breast carcinoma and one with Hodgkin's lymphoma) presented with symptoms in the arm and hand. To exclude metastases or tumor recurrence MR imaging was performed. RESULTS AND CONCLUSION: In one patient, fibrosis showing low signal intensity was found, while in two patients high signal intensity fibrosis surrounding the brachial plexus was found on the T2-weighted images. In one case gadolinium enhancement of the fibrosis was seen 21 years after radiation therapy. It is concluded that radiation-induced brachial plexopathy can have different MR imaging appearances. We found that radiation fibrosis can have both low or high signal intensities on T2-weighted images, and that fibrosis can enhance even 21 years after radiation therapy.

Magnetic resonance imaging of the brachial plexus in patients with multifocal motor neuropathy.

We studied whether magnetic resonance (MR) imaging of the brachial plexus is useful to distinguish multifocal motor neuropathy (MMN) from lower motor neuron disease (LMND) and whether abnormalities resemble those of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We compared MR images of the brachial plexus of nine patients with MMN with scans from five patients with CIDP, eight patients with LMND, and 174 controls. In two patients with MMN, and in three patients with CIDP, the MR images showed an increased signal intensity on the T2-weighted images of the brachial plexus. Two other patients with MMN demonstrated a more focal, increased signal intensity on the T2-weighted images, occurring in one patient only in the axilla, and in the other patient in the axilla and in the ventral rami of the roots. MR images of the brachial plexus of eight patients with LMND were normal. The distribution of the MR imaging abnormalities corresponded with the distribution of symptoms of the patients: asymmetrical in MMN and symmetrical in CIDP. These findings demonstrate that MR imaging abnormalities of the brachial plexus in patients with MMN resemble those seen in CIDP and may be useful to distinguish MMN from LMND.

CT prediction of irresectability in esophageal carcinoma: value of additional patient positions and relation to patient outcome.

BACKGROUND: To improve computed tomographic (CT) prediction of local irresectability and to correlate preoperative CT findings with patient outcome. METHODS: Eighty-five patients with esophageal carcinoma underwent CT in supine, left lateral decubitus, and prone positions. CT signs that were indicative of local irresectability included (1) an angle of contact >45 degrees with the aorta; (2) obliteration of triangular fat pad between the tumor, aorta, and spine; (3) tumor contiguous with the aorta in all three positions; and (4) indentation of the airway in all three positions. RESULTS: All CT signs indicative for local irresectability concerning the aorta had comparable percentages of false-positive scans (75%) when correlated with surgical findings. When correlated with pathologic findings, >45 degrees angle of contact with the aorta yielded the fewest false-positive cases (9%). Concerning the airway, additional positions changed the staging correctly in 1 of 18 cases. Median survival was 21 and 8 months, respectively, for tumors considered CT resectable or irresectable. CONCLUSION: Additional patient positions do not improve the CT prediction of aortic invasion. Predicted resectability correlates with a significant longer life expectancy.

Focal liver lesions: characterization with triphasic spiral CT.

PURPOSE: To assess whether triphasic spiral CT enables characterization of a wide range of focal liver lesions. MATERIALS AND METHODS: One hundred five patients with suspected focal liver disease underwent triphasic liver CT. After injection of contrast material, the liver was scanned in arterial (scanning delay, 22-27 seconds), portal (scanning delay, 49-73 seconds), and equilibrium (scanning delay, 8-10 minutes) phases. Enhancement of each lesion in each phase was evaluated, and the lesions were tabulated according to one of 11 enhancement patterns. RESULTS: In 94 patients, 375 liver lesions were detected. The nature of the lesion was confirmed in 326 lesions (87%). Six of 11 enhancement patterns were always due to benign disease and caused by areas with hyper- or hypoperfusion, hemangiomas, cysts, focal nodular hyperplasias, or benign but nonspecified lesions. Two of 11 patterns were always due to malignant disease, and one pattern was due to malignant disease in 38 (97%) of 39 patients with known malignancy elsewhere or with chronic liver disease. The other two patterns were seen in metastases and partly fibrosed hemangiomas. CONCLUSION: Triphasic liver CT enables characterization of a wide range of focal liver lesions, including the benign liver lesions that occur most frequently.

Chest imaging with a selenium detector versus conventional film radiography: a CT-controlled study.

PURPOSE: To compare radiologist detection performance under clinical conditions for assessment of conventional radiographs and digital chest images obtained with a selenium detector. MATERIALS AND METHODS: One hundred four patients were examined with the digital and conventional systems under near identical technical conditions. The digital images were acquired without an antiscatter grid. Two hundred eight images were analyzed by three radiologists for detection of pulmonary, mediastinal, and pleural abnormalities; computed tomography was used as the reference standard. The diagnostic value of both techniques for the detection of these chest abnormalities was analyzed with receiver operating characteristic (ROC) methods. RESULTS: For detection of the various abnormalities by all radiologists, the areas under the ROC curves with conventional imaging versus digital imaging, respectively, were as follows: pulmonary opacities, 0.81 versus 0.79; interstitial disease, 0.69 versus 0.73; mediastinal disease, 0.79 versus 0.74; and pleural abnormalities, 0.73 versus 0.68. CONCLUSION: There was no statistically significant difference between the radiologists' performance in detecting pulmonary, mediastinal, and pleural abnormalities with conventional radiography versus that with digital selenium chest radiography.

Effects of dose reduction on digital chest imaging using a selenium detector: a study of detecting simulated diffuse interstitial pulmonary disease.

OBJECTIVE: The purpose of this study was to evaluate the effect of dose reduction on the diagnostic performance of a new digital chest imaging system in which amorphous selenium is used as the X-ray detector. Diagnostic performance was assessed for the detection of simulated diffuse interstitial pulmonary disease (DIPD). MATERIALS AND METHODS: DIPD was simulated by superimposing plastic sheets that contained small radiopaque objects (birdseed) on an anthropomorphic chest phantom. We varied the number of sheets from zero to four to simulate the degree of abnormality. We made 80 images with a standard X-ray dose, 80 images with 55% of the standard dose, and 80 images with 35% of the standard dose. Six observers were asked to indicate the presence of DIPD using a five-level scale of confidence. Two hundred forty chest images were then analyzed using receiver operating characteristic (ROC) curves. RESULTS: The area under the ROC curve was 87.2 for all readers with standard-dose imaging (95% confidence interval [CI], 83.7-90.7), 91.7 with 55% of the standard dose (95% CI, 88.8-94.6), and 90.0 with the 35% dose (95% CI, 87.1-92.9). The area under the ROC curve for subtle DIPD (one superimposed sheet) was 75.3 for all readers with standard-dose imaging (95% CI, 67.1-83.5), 79.7 with 55% of the standard dose (95% CI, 71.9-87.5), and 70.3 with the 35% dose (95% CI, 61.7-78.9). For each dose, we observed a gradual improvement of the ROC curves with each additional sheet superimposed on the chest phantom (p < .001). CONCLUSION: We found no significant difference in diagnostic performance among images made with standard X-ray dose, those made with a 55% dose, and those made with a 35% dose (95% CI).

From medical history and biochemical tests to presymptomatic treatment in a large MEN 2A family.

An extensive study was published in 1959 in the Netherlands on a large family, which initially attracted attention because of a family history of attacks of shaking. Clinical investigation revealed phaeochromocytomas in four family members. In 1975, the family was identified to be a MEN 2A family, and since then, the members were examined annually using measurement of catecholamine metabolites in 24-h excreted urine and C-cell stimulation tests. In 1993, the RET proto-oncogene on chromosome 10q11 was found to be associated with MEN 2A and a specific mutation in this gene was identified in the family. In this family, 32 MEN 2A patients were detected. Since screening started in 1975, no patient died of phaeochromocytoma; however, two patients died of metastasized medullary thyroid carcinoma (MTC) (mean age 46 years). Twelve patients were operated on for phaeochromocytoma, and 13 for MTC. The results of DNA-analysis revealed the failures of the biochemical tests to identify affected family members. Six disease gene carriers with normal C-cell stimulation test results appeared to have small multifocal MTCs. Two carriers with normal excretion levels of catecholamines had a small phaeochromocytoma. DNA-analysis enables the unambiguous diagnosis of MEN 2A gene carrier-ship, allowing presymptomatic surgery for MTC.

Digital chest imaging with a selenium detector: comparison with conventional radiography for visualization of specific anatomic regions of the chest.

OBJECTIVE: The purpose of this study was to compare a new digital chest radiography system that uses amorphous selenium as the X-ray detector with conventional radiography for the visualization of various anatomic regions of the chest as a first phase of testing image quality. MATERIALS AND METHODS: Six observers analyzed pairs of posteroanterior chest radiographs of 40 patients. One radiograph in each pair was obtained with a conventional chest film changer, and the other was obtained with the digital selenium chest radiography system. Each observer rated the visibility and the radiographic quality of 12 different anatomic regions. RESULTS: The observers rated visualization obtained with the digital system as better than that obtained with the conventional system in four regions (right lower lobe, upper lobes, ribs, and soft tissue), as better than or equal to that obtained with the conventional system in four regions (retrocardiac, retrodiaphragmatic, hilum, and upper mediastinum), and as equal to that obtained with the conventional system in four regions (horizontal fissure, carina, azygoesophageal recess, and thoracic spine). Some observers had a strong preference for the digital images, whereas others showed no preference. The conventional system was not ranked high for any region (2880 observations, p < .01, sign test). CONCLUSION: The digital selenium chest radiography system performs well in a clinical setting, providing visualization of anatomic structures that is better than or at least equal to that provided by standard screen-film images.

Planning of liver surgery using three dimensional imaging techniques.

In the simplified Couinaud classification, in which the liver is divided into eight segments, each supplied by a central vasculo-biliary sheath, little attention is given to the high prevalence of anatomical variations which occur, especially in the right hemiliver. Using volumetric acquisition techniques, such as magnetic resonance imaging or spiral computed tomography scanning, detailed insight into the individual segmental anatomy can now be obtained in a non-invasive manner. The significance of this anatomical insight lies in the planning of anatomical resections, whereby the relationship between tumour and individual segmental anatomy can be depicted in a three-dimensional format. As such, three dimensional (3D) liver imaging helps to design an individualised resection, tailored to the topographical relationship between individual segmental anatomy and tumour tissue present. Three dimensional liver imaging is of most practical value if a resection of one or more segments or sectors is considered, especially in the right hemiliver. In these cases, 3D liver imaging can demonstrate the precise location of the scissuras to the surgeon pre-operatively.

Portal venous and segmental anatomy of the right hemiliver: observations based on three-dimensional spiral CT renderings.

OBJECTIVE: The purpose of this study was to evaluate the segmental anatomy of the right hemiliver and to assess whether the right hepatic vein and right portal trunk are accurate indicators of the position of the right and transverse scissurae, respectively. SUBJECTS AND METHODS: We examined 26 patients with spiral CT using 5-mm slices, reconstructed at 2-mm intervals. Three-dimensional renderings of the portal and hepatic venous structures were created. The portal ramification pattern and relationship between the hepatic veins and portal system were evaluated. RESULTS: In the right hemiliver, an anterosuperior sector and a posteroinferior sector were present in all patients. In addition, in nine patients, a total of 15 accessory portal sectors were present, each arising directly from the portal bifurcation or the right portal trunk. Further subdivision of the portal sectors showed marked individual variability, with no prevailing branching pattern. The scissura between the anterosuperior and posteroinferior sectors showed an angled orientation--its cranial part was tilted posteriorly (average, 58.4 degrees) and its caudal part was tilted anteriorly (average, 2.8 degrees)--relative to the coronal plane. In 24 patients, portal branches crossed the plane of the right hepatic vein. No transverse scissura could be seen in the anterosuperior or posteroinferior sector. CONCLUSION: The right hemiliver could be divided into anterosuperior and posteroinferior sectors in all patients studied. Many patients have accessory sectors. Further subdivision into portal segments can be described only after the individual portal branching pattern has been studied. The right hepatic vein is an inaccurate indicator of the position of the right scissura. No clear transverse scissura can be seen in the right hemiliver.

Von Hippel-Lindau disease: new strategies in early detection and treatment.

UNLABELLED: Von Hippel-Lindau disease is an autosomal dominant inherited disorder causing hemangioblastomas of the central nervous system (CNS), retinal hemangiomas, renal cell carcinomas, pheochromocytomas, pancreatic and liver cysts, and epididymal cystadenomas. PURPOSE: Since 1976, we have periodically screened for the lesions in a large affected family and were able to evaluate new strategies in detection and treatment. PATIENTS AND METHODS: A total of 23 individuals underwent the screening program. A multidisciplinary team of physicians was involved. RESULTS: In 13 patients (7 females and 6 males), a total of 31 tumors was detected; hemangioblastoma of the CNS (9), retinal angioma (4), renal involvement (8), pheochromocytoma (4), pancreatic lesions (4), and liver lesions (2) were diagnosed by periodic family screening. On the basis of more than 10 years of experience and current literature, new criteria for diagnosis and treatment have been proposed. CONCLUSION: The von Hippel-Lindau disease gene appears to be a tumor suppressor gene, and its absence or a defect in its structure is responsible for the predisposition to the disease. Tumor development depends on a somatic second mutation in the homologous allele. That means, in disease-gene carriers, tumor growth may begin at any age. Most of the lesions can be treated successfully when diagnosed in time. Periodic screening by a multidisciplinary team has to be continued lifelong.

Variations in venous and segmental anatomy of the liver: two- and three-dimensional MR imaging in healthy volunteers.

OBJECTIVE: The purpose of this study was to use two- and three-dimensional analysis of thin-slice MR imaging data to study the anatomic variations in the segmental anatomy of the liver. It is important to recognize these anatomic variations in order to ensure accurate localization of hepatic lesions and preoperative delineation of resection planes. SUBJECTS AND METHODS: T1-weighted MR images of contiguous 4-mm sections were obtained in 10 healthy subjects. We measured the orientations of external and internal hepatic landmarks that indicated segmental boundaries and created three-dimensional renderings of hepatic veins, intrahepatic portal branches, liver surface, and gallbladder. RESULTS: Variations in the portal branching pattern were seen in eight of 10 subjects. Most variations occurred in the right hemiliver and consisted of the absence of a right portal trunk or the presence of accessory portal branches. The division between right anterior and right posterior segments was inclined posteriorly (average, 31.2 degrees) relative to the right hepatic vein. The landmarks indicating the position of the umbilical fissure showed marked variability. Only two of 10 subjects had three hepatic veins, with the left and middle veins sharing a common trunk. In the remaining eight subjects, nine accessory veins were present: three left, one middle, and five right. CONCLUSION: Planes of resection in liver surgery are largely determined by the precise position of tumor relative to the individual segmental anatomy. Consequently, localization of liver lesions and preoperative delineation of resection planes requires consideration of the significant anatomic variations in the segmental anatomy of the liver. These anatomic variations can be depicted on two- and three-dimensional displays of T1-weighted MR images of contiguous 4-mm sections.