Radiological emergency room management with emphasis on multidetector-row CT.

Trauma is the fifth leading cause of death after disease of the cardiovascular system, malignomas and disease of the respiratory and digestive system. The management of severely injured patients, including radiological imaging, is a matter of ongoing development. In particular, as for the imaging modalities, multidetector-row CT represents a substantial refinement in the diagnostic work-up of multitrauma patients. Sufficient therapy within the first hour after trauma increases the patient's chances for survival significantly. Thus, therapeutic procedures and diagnostic evaluation have to be concomitant events, performed by a multidisciplinary team, namely trauma surgeon, anesthesiologist and, last but not least, radiologist. The increased performance of multidetector-row CT leads to increased spatial resolution, which is a prerequisite for sophisticated two- and three-dimensional postprocessing. The increased volume coverage speed allows for comprehensive whole-body CT at still high levels of spatial resolution, resulting in significant spare of time which influences patient's survival. Using this technique conventional imaging such as plane film or angiography may be omitted.

Scaphoid fractures: evaluation with high-spatial-resolution US initial results.

PURPOSE: To evaluate the diagnostic accuracy of high-spatial-resolution ultrasonography (US) in the diagnosis of scaphoid fractures. MATERIALS AND METHODS: In 72 hours after acute wrist trauma, 15 consecutive patients were examined for possible scaphoid fractures clinically and with conventional radiographs, including scaphoid views. Thereafter, high-spatial-resolution US was performed by two experienced radiologists blinded to the results of the previously performed investigations. High-spatial-resolution US of the scaphoid bones was performed from the palmar, lateral, and dorsal directions in the longitudinal and transverse planes. US findings indicative of a scaphoid fracture were cortical discontinuity and/or periosteal elevation. Finally, magnetic resonance (MR) images (short inversion time inversion-recovery, T1- and T2*-weighted) (ie, the standard) of the affected wrist were obtained and evaluated for a possible scaphoid fracture by two radiologists in consensus. RESULTS: Nine of 15 patients had scaphoid fractures. Seven (78%) of nine patients had positive findings at high-spatial-resolution US and five (56%) had such findings at conventional radiography (ie, four occult scaphoid fractures), with an accuracy of 87% and 73%, respectively. Two (50%) of four radiographically occult scaphoid fractures were depicted with high-spatial-resolution US. Sonographic findings of scaphoid fractures were either cortical discontinuity (n = 4), periosteal elevation (n = 2), or a combination of these two findings (n = 1). CONCLUSION: High-spatial-resolution US is a reliable diagnostic tool for the evaluation of occult scaphoid fractures and should be considered an adequate alternative diagnostic tool prior to computed tomography or MR imaging.

[Trauma of the bones of the hand and wrist]. / Knöchernes Hand- und Handgelenktrauma.

Fractures of the distal radius are common counting for 17 percent of all fractures. With conventional radiography they can be classified readily. Magnetic resonance imaging (MRI) is a suitable technique for the detection of occult forms of fractures and of associated soft tissue injuries. In the wrist, fractures are 10 times less common than in the distal radius, with the scaphoid bone to be involved most commonly. Indications for computed tomography (CT) are complex fractures, occult fractures, or dislocations. MRI should be performed to evaluate the soft tissues, to detect occult fractures, or to analyse osteochondral lesions. Indications for arthrography are injuries of the ligaments or of the joint capsule. Fractures and dislocations of the metacarpal, and the phalangeal bones are the most common fractures of the skeletal system. Conventional radiography is the primary imaging technique, followed by sonography and MRI to detect injuries of the ligaments and tendons.

[Necrotizing enterocolitis (NEC) in the newborn]. / Nekrotisierende Enterokolitis (NEC) beim Neugeborenen.

Necrotizing enterocolitis (NEC) is a disease of the premature neonate that requires early therapy, sometimes even surgery and therefore early diagnosis. In general, plain radiography of the abdomen and sonography are valuable imaging techniques for diagnosis of NEC. COURSE OF NEC: The disease starts with distension of small bowel loops. Furthermore the children develop pneumatosis in the bowel wall, which is a nonspecific pattern. If the NEC persists, the air passes into the portal vein system, causing a pneumoportogram. Finally, the disease can lead to perforation. In doubtful cases, the plain radiogram must be repeated within a period of 6 h. With sonography distension of the bowel, thickening of and pneumatosis in the bowel wall, the pneumoportogram and free intraperitoneal fluid can be easily depicted. The most common complications of NEC are intestinal stenosis and strictures that can lead to ileus. DIFFERENTIAL DIAGNOSIS: Focal perforation of ileum, volvulus and Hirschsprung's disease are some of the differential diagnoses.

Radiologic measurement of the scapholunate joint: implications of biologic variation in scapholunate joint morphology.

To determine the optimal location for measurement of the scapholunate (SL) joint intercortical width, normal biologic variation in SL joint morphology was evaluated in 40 normal, skeletally mature wrists (16 volunteers, 24 cadavers) using thin-section 1.5T magnetic resonance imaging performed in the axial and coronal planes. The integrity of the SL ligaments was confirmed by magnetic resonance imaging and verified with anatomic dissection of the cadaver wrists. Patterns of SL articular morphology were qualitatively determined using similarity grouping. Scapholunate interval measurements were made at 3 locations each on the mid-SL joint image from both the axial and coronal planes: the articular margins (dorsal-palmar and proximal-distal) and midjoint. Three patterns of midjoint space cortical conformation were observed: parallel congruent (78%), inverted Y (15%), and point-like (8%). The most consistent and narrowest distance between the scaphoid and lunate was found at midjoint: coronal 1.45 mm (44% coefficient of variation) and axial 1.00 mm (22% coefficient of variation). This study demonstrated that measurement of the apparent SL joint interval in an inappropriate site, as with extended or flexed clenched fist views, may provide inaccurate SL joint interval distance assessments. Regardless of SL joint configuration, the midportion of the SL joint shows only moderate biologic variation and the least absolute measurement variance in width and should be the most precise part of the joint to measure. On magnetic resonance imaging, the normal SL joint interval measures less than 2 mm.

MR imaging in children with nonperforated acute appendicitis: value of unenhanced MR imaging in sonographically selected cases.

OBJECTIVE: The aim of this study was to describe the MR appearance of acute appendicitis and to determine the value of MR imaging for diagnosis of acute appendicitis. SUBJECTS AND METHODS: Forty-five children (28 girls, 17 boys), 7-16 years old (mean age, 13 years old), with clinically diagnosed acute appendicitis underwent independently graded compression sonography by two radiologists. MR imaging was performed when sonography revealed acute appendicitis (observer 1, 16 [36%] patients; observer 2, 18 [40%] patients), was inconclusive (observer 1, two [4%] patients; observer 2, one [2%] patient), and was interpreted as normal (observer 1, two [4%] patients; observer 2, one [2%] patient) (n = 20). Axial T1-weighted turbo spin-echo sequences, T2-weighted turbo spin-echo sequences in the axial and coronal planes, and fat-suppressed short inversion time inversion recovery turbo spin-echo sequences in the axial plane (4-mm slice thickness) were obtained and evaluated independently by two radiologists. The ability to see acute appendicitis with MR imaging was evaluated, the appearance and morphologic changes were described, and the most accurate sequence was determined. All children in whom MR imaging was performed underwent surgery. RESULTS: MR imaging revealed acute appendicitis in all cases (100%) by both observers. On T2-weighted ultra turbo spin-echo images, acute appendicitis appeared with a markedly hyperintense center, a slightly hyperintense thickened wall, and markedly hyperintense periappendiceal tissue. Unenhanced axial T2-weighted spin-echo imaging was the most sensitive sequence. CONCLUSION: In this study group, MR imaging was a valuable technique for depiction of acute appendicitis.

Ligamentous instabilities of the wrist.

Carpal ligament instabilities are conditions in which the individual carpal bones have become unstable due to abnormal ligament support. Early diagnosis of ligamentous wrist instabilities is important because late diagnosis or failed diagnosis may lead to severe complications such as osteoarthritis. This article reviews the most common ligamentous instability patterns of the wrist and focuses on how to perform and obtain radiograms which will allow reliable diagnosis of wrist instabilities.

Diaphragmatic dysfunction after heart or lung transplantation.

BACKGROUND: The aim of this study was to evaluate the incidence and outcome of diaphragmatic dysfunction in patients after heart or lung transplantation and to assess the value of bedside sonography for the detection of diaphragmatic dysfunction. METHODS: We prospectively evaluated 33 heart transplant recipients and 27 lung transplant recipients by use of sonography of the diaphragm and fluoroscopy. RESULTS: Diaphragmatic dysfunction, diagnosed with ultrasonography and confirmed with fluoroscopy, was present in four heart transplant recipients (12.1%) and two lung transplant recipients (7.4%) and such dysfunction led to a statistically significant higher incidence of pneumonia during hospitalization and a nonstatistically significant increased length of intubation compared with patients with normal diaphragmatic function. CONCLUSION: Diaphragmatic dysfunction, which can be reliably diagnosed with bedside sonography, is common after heart and lung transplantation and seems to have a negative influence on patient recovery.

Radiographically occult scaphoid fractures: value of MR imaging in detection.

PURPOSE: To evaluate the diagnostic value of magnetic resonance (MR) imaging in patients with clinical suspicion of scaphoid fractures and normal initial plain radiographs. MATERIALS AND METHODS: MR imaging was performed within 7 days after trauma in 42 patients with clinical suspicion of scaphoid fractures and normal plain radiographs. T1-weighted spin-echo, T2*-weighted gradient-echo, and short inversion time inversion-recovery (STIR) sequences were performed. MR images were evaluated independently by two radiologists. Six-week follow-up radiographs were used as a standard to diagnose fractures. RESULTS: MR imaging depicted occult fractures of the scaphoid bone in 14 patients (33%), the capitate bone in four (10%), the trapezium in one (2%), and the distal radius in two (5%). All wrist fractures were detected with a combination of STIR and T1-weighted spin-echo sequences. The sensitivity and specificity for detection of radiographically occult fractures of the wrist were 100% each for the first and 95% and 100%, respectively, for the second radiologist with an almost perfect interobserver agreement (K = 0.953). CONCLUSION: MR imaging has a high sensitivity for detection of fractures of the scaphoid bone and wrist not evident on plain radiographs and may enable early diagnosis and treatment.

Intraoperative and early postoperative colour Doppler sonography after carotid artery reconstruction: follow-up of technical defects.

We studied 50 patients with intraoperative colour-coded Doppler sonography (CCDS) after carotid artery reconstruction. Technical defects could be detected in 19 cases (38 %): residual plaques in 9, flaps in 8 and strictures in 2. In 9 cases (18 %) the carotid endarterectomy was revised. One residual plaque and one residual stricture caused thrombosis at the operative site a few hours postoperatively. One of the patients with residual plaques developed a high-grade stenosis within the follow-up period. Of the patients with residual plaques two had a medium-grade stenosis at follow-up. Six flaps decreased in size or disappeared within 1 week after operation. No patient with a flap developed a stenosis within the follow-up period. Our findings seem to indicate that correction of intimal flaps less than 10 mm in size is not necessary.

Pseudopericardial effusions in heart transplant recipients.

BACKGROUND: The objective of this study was to determine the nature of sonographically observed band-shaped, homogeneous, almost echo-free structures located ventral to the right ventricle of the heart in heart transplant recipients. METHODS: A total of 212 consecutive heart transplant recipients was evaluated sonographically. RESULTS: In 18 of the 212 patients (8.5%) band-shaped structures were detected, and these structures were proved with computed tomography or magnetic resonance imaging to be caused by mediastinal fat. CONCLUSIONS: A sonographically demonstrable, almost echo-free band-shaped structure located ventral to the heart should not be misinterpreted as localized pericardial effusion.

Update on imaging techniques of the wrist and hand.

Several imaging techniques are available and necessary for evaluation and treatment of hand and wrist pathology. Conventional radiography is still the imaging technique of first choice for evaluation of abnormalities of the wrist and hand. Bone scintigraphy is an important diagnostic tool with a high sensitivity but low specificity. Arthrography should be performed if abnormality of ligamentous or triangular fibrocartilaginous pathology is suspected; however, using arthrography, all three major compartments and both wrists should be examined arthrographically. In selected cases, such as occult fractures, fracture healing, and early detection of avascular necrosis, advanced imaging techniques, such as magnetic resonance imaging and computed tomography, may be necessary and are helpful to achieve correct diagnosis.

[Functional anatomy and biomechanics of the ankle joint]. / Funktionelle Anatomie und Biomechanik des Sprunggelenks.

Functional anatomy is fundamental for understanding motion in the ankle joint. Biomechanical studies try to evaluate the forces and torque affecting biological tissue under various conditions and therefore the cause and effects of disorders of joint structures. Conclusions based on this research permit preventive arrangements to reduce force and risk of injury to the joints. Biomechanical models describe the function of joint movements. A knowledge of biomechanical models may affect therapy management of patients with joint disorders. For the radiologist the results of this basic research are of major importance. Knowledge of pathological joint movements allows more accurate diagnosis of complex disorders or injuries of the ankle joint and structural alterations in bony or soft tissue structures, as demonstrated by MRI. In this article, we summarize the results of functional anatomy and biomechanics of the ankle joint reported in the literature.

Wide scapholunate joint space in lunotriquetral coalition: a normal variant?

The radiologic appearances of 70 lunotriquetral coalitions in 52 patients were evaluated to determine whether a wide scapholunate joint space in subjects with this congenital abnormality reflects a scapholunate ligament disruption or is a normal variant. When the middle of the scapholunate joint space was larger than the capitolunate or third carpometacarpal joint space widths, it was considered to be abnormally wide. In 32 of 70 wrists (46%), a wide scapholunate joint space was detected. Results of instability radiographic series (n = 28) and arthrography (n = 11) were normal with respect to the scapholunate ligament in all cases, but the scapholunate joint space was markedly widened in six cases (55%) in which arthrography was performed. Arthroscopy, performed in one case, showed an intact scapholunate ligament. Because of the high prevalence of a wide scapholunate joint space and because of negative arthrographic and arthroscopic examinations, the authors conclude that widening of the scapholunate joint space is a normal variant that is common in patients with lunotriquetral coalition.

Is this scapholunate joint and its ligament abnormal?

There is confusion in the literature with respect to evaluation of the scapholunate joint space and ligament. Because routine x-ray films of the wrist commonly do not profile the scapholunate joint perfectly, determination of the joint space width often is inaccurate. One method that invariably will allow a good profile of the scapholunate joint involves the use of fluoroscopically controlled views in different positions of the wrist. However, when abnormal width is suspected, in all examinations the wrist in question should be compared with the opposite wrist and the findings carefully correlated with clinical symptoms. Additional arthrographic findings, which have not been discussed in the literature before, are described. Midcarpal arthrography identifies and illustrates a variety of appearances of the scapholunate ligament. The reason for these different appearances and whether they are normal variations or pathologic findings is not known. This article is designed to stimulate further clinical and x-ray research to clarify normal and abnormal features of the scapholunate joint and ligament.

Lack of correlation between site of wrist pain and location of noncommunicating defects shown by three-compartment wrist arthrography.

OBJECTIVE: Communicating defects shown by wrist arthrography often correlate poorly with the location of the patient's symptom(s). No study of wrist arthrography in which noncommunicating defects have been isolated, described, and correlated with the site of patients' symptoms has been reported. The aim of this study was to correlate the site(s) of patients' pain and the location(s) of noncommunicating defects shown by wrist arthrography. MATERIALS AND METHODS: One hundred noncommunicating capsular defects and incomplete defects of the interosseous ligaments and triangular fibrocartilage in 82 patients were identified from 462 three-compartment wrist arthrograms. Correlation between the sites of pain and sites of the noncommunicating defect was described as: (1) exact correlation, (2) ulnar/radial side correlation, (3) ambiguous correlation, or (4) no correlation. Statistical analysis was performed for each type of defect separately, in aggregate for patients who had more than one defect, and by separate analysis using patients' age (less than or greater than 30 years old). RESULTS: Capsular defects were detected in 65 patients, incomplete perforations of the triangular fibrocartilage in 28 patients, and incomplete defects of the scapholunate and lunotriquetral ligament in three patients each. No statistically significant correlation was found between individual defects and symptoms or between the site(s) of symptoms and patterns of multiple noncommunicating defects. Further, age did not influence the degree of correlations (chi 2 = 0.000-0.476, p values = 0.49-1.00). CONCLUSION: Attribution of patient's symptoms to noncommunicating defects shown by wrist arthrography is not reliable. Cases in which site-specific arthrographic defects directly correlate may be fortuitous. Additional studies will be necessary to determine the future role of wrist arthrography in the evaluation of the painful wrist.

Imaging techniques for distal radius fractures and related injuries.

In patients with distal radius fractures, routine roentgenographic examination in at least two or three planes should be performed first and is usually sufficient for correct diagnosis and adequate treatment. A careful examination of the soft tissues of the forearm and wrist on conventional roentgenograms may be key for correct diagnoses. Routine roentgenographic examination of the wrist, preferable in four views, should be performed in every patient with a distal radius fracture acutely as well as at follow-up. The technique is easy to perform, universally available, and inexpensive. Advanced imaging techniques such as radionuclide bone imaging, CT, or MR imaging should not be first choice modalities in patients with distal radius fractures and should be used only when conventional roentgenograms are inconclusive. Scintigraphy can be helpful for diagnosing occult fractures, for documenting fracture healing and ligamentous or cartilaginous post-traumatic disorders, as well as for diagnosis and follow-up of reflex sympathetic dystrophy. A disadvantage of scintigraphy is its poor specificity. Indications for CT include the confirmation of occult fractures suspected on the basis of the findings of physical examination and focally hot bone scintigrams when plain films are normal or inconclusive. In comparison with conventional radiography, CT is superior for the preoperative evaluation of complex comminuted distal radius fractures, depicting the distal radial articular surface and size and position of fracture fragments, as well as for the assessment of fracture healing. Additionally, CT is the imaging technique of choice for the correct diagnosis of subluxations of the distal radioulnar joint. Magnetic resonance imaging is an important diagnostic technique for the evaluation of suspected injuries of soft tissues related to distal radius fractures, such as to the flexor and extensor tendons or the median nerve, and for the early diagnosis of necrosis of the scaphoid or lunate. Other indications include identification of triangular fibrocartilage complex perforations, ruptures of carpal ligaments, and demonstration of contents of the carpal tunnel.

Three-compartment wrist arthrography: correlation of pain site with location of uni- and bidirectional communications.

OBJECTIVE: Our objective was twofold: (1) to determine whether the site of patients' pain correlates with abnormal findings on three-compartment wrist arthrograms and (2) to determine whether the directional nature (uni- vs bidirectional) of communication(s) between adjacent wrist joint compartments shown on three-compartment wrist arthrograms correlates with the presence and site of pain. MATERIALS AND METHODS: We retrospectively studied 462 three-compartment wrist arthrograms of 458 patients. The patients were divided into four groups according to the site of pain, the correlation of that site with the site of the communication, and the directional characteristics of communications shown on the arthrogram: (1) exact correlation between site of pain and arthrographic findings, (2) correlation only between side of pain (ulnar or radial) and arthrographic findings, (3) ambiguous correlations (e.g., multifocal, midline, or diffuse pain), and (4) no correlation between site of pain and arthrographic findings. RESULTS: In 191 patients (42%), 226 intercompartmental communications were detected (51 uni- or 173 bidirectional). One hundred sixty-one patients had only one communication (uni- or bidirectional), and 30 patients had more than one (uni- and/or bidirectional) communication for a total of 65 defects. Regardless of the directional nature of the communication, no positive association between sites and/or the side of symptoms and sites of communications was demonstrable. However, a potential association appears to exist between ulnar-sided pain and combined lunotriquetral and triangular fibrocartilage tears. CONCLUSION: Our results suggest that the directional nature of interjoint communications has little or no clinical significance. Thus, with the exception of seeking the cause of ulnar-sided pain, our results question the usefulness of routine arthrography for correlating sites of patients' symptoms and individual interjoint communications.

Age-associated changes of the triangular fibrocartilage of the wrist: evaluation of the diagnostic performance of MR imaging.

To define the appearance of degenerative changes of the triangular fibrocartilage (TFC) of the wrist on magnetic resonance (MR) images, the TFCs in one wrist of each of 30 healthy subjects in three age groups (20-35, 36-50, and greater than 50 years) and six TFCs from fresh cadavers were examined by means of coronal T1-weighted spin-echo sequences. Histologic findings were compared with findings on MR images in the cadaveric TFCs. It was proved that patches or lines of signal hyperintensity within the cadaveric TFCs were caused by degenerative changes and tears. Similar changes of the TFCs on MR images of the healthy subjects may have been caused by degeneration. In the healthy subjects, degenerative changes of the TFC, usually well defined on MR images, occurred at a very early age. The TFC appears to undergo stages of degeneration comparable to those of the menisci of the knee, but differentiation between traumatic and degenerative tears may be difficult.