Roentgen diagnosis of midfacial fractures

The course and configuration of typical maxillofacial fractures (type Le Fort I-III) and lateral maxillary fractures including the zygomatic arch were reconstructed in detail by application of barium paste on a bony skull and radiographs in standard projections were performed and evaluated. It was obvious from the resulting radiographs that for most maxillofacial fractures a half axial or Water's view was most helpful. Lateral views only give additional information when there is a considerable degree of dislocation of fragments. Comparison with a pediatric skull of 8 years of age demonstrated that fractures of the zygomatic arch in this age group cannot be demonstrated by the typical submento-vertical view, but are shown on a Towne projection. The radiographic appearance of important maxillofacial fractures is demonstrated. The necessity of further studies in cases where reconstructive surgery appears necessary is discussed and CT rather then conventional tomography is advocated.     

Inferomedially projecting pneumatised secondary middle turbinate

Secondary middle turbinate (SMT), a rare variation of the nasal cavity, is a bony projection covered by soft tissue that arises from the lateral nasal wall. It is almost always bilateral and usually projects superomedially without any ostiomeatal unit obstruction. Herein, we report a case of bilateral inferomedially projecting secondary middle turbinates, one of which is pneumatised and hypertrophied, resembling a large ethmoid bulla extending into the middle meatus. The recognition of this variation is important since it may predispose to inflammatory sinus disease, by narrowing the ostiomeatal unit.     

The assimilated os sustentaculi

The assimilated os sustentaculi is a projection of bone from the medial aspect of the sustentaculum tali which is surmounted by a similar projection from the medial tubercle of the talus. The accessory joint so formed may develop secondary osteoarthritis changes. This congenital anomaly is very rate. The present report is of 2 additional cases.     

Adaptation of the technique for radiography of the glenohumeral joint in the lateral position

This article emphasizes the importance of obtaining opposing right angle views of the shoulder as a routine part of the examination. It analyses standard projection techniques and presents an adaptation of the transaxillary axial projection that is invaluable to the radiologist in diagnosing that eight per cent of lesions that can be missed by not using this projection.     

Pulmonary angiography for pulmonary emboli: rational selection of oblique views.

In the performance of pulmonary arteriography, the anteroposterior projection may be insufficient for the diagnosis of pulmonary embolism, and additional views, usually oblique, are required. Of 57 positive pulmonary arteriograms which were reviewed, additional views were necessary in 26 cases. The efficacy of the additional views in each case was assessed with regard to the demonstration of the segmental arteries of the various lobes of the lung. Following an inconclusive anteroposterior injection, the best visualization of the arteries of the right lung can generally be obtained with an injection made in the right posterior oblique projection. Similarly, following an inconclusive anteroposterior injection, the left posterior oblique or lateral view is recommended for optimal visualization of the pulmonary vasculature of the left lung.     

Centroid-based maximum intensity projections.

PURPOSE: Maximum intensity projection (MIP) is a three-dimensional visualization technique for tomographic angiograms. While conventional MIPs display contralateral vascular anatomy, this study uses centroid calculations to remove this information. It is necessary to provide accurate, unambiguous vessel depiction and identical projections regardless of slice orientation. METHOD: A mathematical model was formed using parameters from clinical images of the head. The vessel widths from the resulting projections were measured and compared with the model. To test the consistency of the projection process, a clinical image set was reformatted and projections of the same view were compared. RESULTS: The vessel widths were smaller than in the model while varying interpolation and noise. Similar projection views were generated for all slice orientations, but some misalignment was present. CONCLUSION: Vessel width is affected by the ray's path length and interpolation method. Some slight misalignment is present because the reformatting process alters the centroid calculations.     

Focal asymmetric densities seen at mammography: US and pathologic correlation.

The American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) defines four different types of asymmetric breast findings: asymmetric breast tissue, densities seen in one projection, architectural distortion, and focal asymmetric densities. These lesions are frequently encountered at screening and diagnostic mammography and are significant because they may indicate a neoplasm, especially if an associated palpable mass is present. Once these lesions are detected at standard mammography, supplementary breast imaging with additional mammographic views and ultrasonography (US) can be a key aspect of work-up. The role of US in this setting has not been clearly defined. However, a positive US finding such as a solid mass or an area of focal shadowing increases the level of suspicion for malignancy. A thorough knowledge of the patient's clinical history, along with a fundamental understanding of the ACR BI-RADS lexicon and the role and limitations of supplementary breast imaging, will allow more accurate interpretation of these potentially perplexing soft-tissue findings.     

Sonography of the medial and lateral tendons and ligaments of the knee: the use of bony landmarks as an easy method for identification

OBJECTIVE: Our purpose was to describe the use of bony landmarks in the evaluation of the medial and lateral ligaments and tendons of the knee on sonography and to evaluate the value of this approach in healthy volunteers. MATERIALS AND METHODS: Anatomic slices obtained in cadaveric specimens were inspected for the presence of bony landmarks on the medial and lateral aspects of the knee. Then sonography was performed on 40 knees of 20 healthy volunteers by two musculoskeletal radiologists who independently rated the visualization of bony landmarks and adjacent ligaments and tendons on a 5-point grading scale. RESULTS: Bony landmarks on the lateral aspect of the knee include Gerdy's tubercle on the tibia and the sulcus for the popliteal tendon on the femur. Landmarks on the medial aspect of the knee include the medial epicondyle on the femur and the sulcus for the semimembranosus tendon on the tibia. Visualization of all landmarks was rated in the good to excellent range, and agreement between observers ranged from 92.5% to 100%. CONCLUSION: Bony landmarks can be identified in healthy adults on the medial and lateral aspects of the knee and may serve as reference points for identification of most medial and lateral tendons and ligaments.     

The uterine contents (author's transl)]

The technique used for radiological examination of the uterine contents must be adapted to the reason for which it is being carried out. In particular, a study of bony maturation of the foetal knee may be carried out using a localised film, with compression and in lateral view, of the maternal abdomen. The technique of the large scoit film in ventral decubitus is reviewed; the study of the uterine contents, on lateral projection, which localisation and compression is described.     

MR angiography with oblique gradient-recalled echo technique

Magnetic resonance (MR) angiography with use of an oblique gradient-recalled echo sequence is discussed. The technique was developed for the efficient acquisition of angiographic data when the desired projection direction is already known. The raw data set is acquired directly at the projection angle; thus, a high-resolution projection is created, despite a decrease in the number of phase-encoding views acquired per axial image. Excessive reduction in the number of views acquired causes a loss of contrast in the projection images rather than a loss of resolution. High-resolution, high-contrast MR projection angiograms can be obtained in 2 1/2 minutes, with 50 3-mm sections and 48 phase encodings per section, a repetition time of 50 msec, an echo time of 15 msec, and a flip angle of 45 degrees. This represents one-fifth the time required for a conventional angiographic image. Venous blood is successfully saturated when the saturation band is placed at a fixed distance from the current imaging section. The method is demonstrated in the imaging of the carotid bifurcation in healthy volunteers and of a patient who had undergone carotid endarterectomy.     

Coils of the cochlea.

Abnormalities of the cochlear portion of the bony labyrinth may often be suspected but are inadequately demonstrated by conventional tomography in the antero-posterior position. Further views are necessary. The authors demonstrate this by means of a comparison between tomographic and histological sections of the inner ear of an anencephalic with a unilateral Mundini defect. Submento-vertical tomograms give a good demonstration of the cochlea.     

Bone scintigraphy in metastatic bone disease

Bone scintigraphy has been widely used in the evaluation of metastatic bone disease. It can provide easy performance of whole body evaluation and high sensitivity for the detection of lesions. However, the indication for bone scintigraphy is revised from views of the less specificity and relatively higher cost than newly introduced diagnostic tools such as CT and MRI in Japan. In order to maintain the present state as a screening test for the evaluation of bone metastasis, more appropriate image acquisition and newly developed radiopharmaceuticals which show the specific accumulation to the metastatic bony lesions will be considered in future.     

Computed tomography of the spinal canal and cord.

Selective cases have been presented to demonstrate the usefulness of computed tomography in disorders of the spine and spinal cord. The osseous structures are more readily demonstrated than the soft tissues. The cord is difficult and inconsistently identified. However, cystic lesions (syringomyelia) may, at times, be demonstrated. The transverse projection of the CT scan is an added benefit in demonstrating bony spinal lesions. The use of metrizamide with faster scanners should improve the usefulness of this technique in evaluating intraspinal lesions.     

Melorheostosis of the hand with complicating bony spur formation and bursal inflammation: diagnosis and treatment

A 37-year old woman presented with intolerable pain associated with a slowly growing mass on the dorsum of the right hand. The radiographs were characteristic of melorheostosis involving the third and fourth metacarpals, with a cortical bony projection extending from the base of the third metacarpal eroding slightly into the fourth metacarpal, associated with bursal formation. Magnetic resonance imaging (MRI) demonstrated an inflamed bursal collection adjacent to the spur. This region corresponded to the patient's severe clinical, focal pain. To our knowledge, this is the first case report in which melorheostosis of the hand has been associated with bony spur formation and complicated by an inflamed bursa.     

Digital filtering of the bladder in SPECT bone studies of the pelvis

A data processing technique for the removal of bladder activity from single photon emission computed tomographic bone studies of the pelvis has been developed. The method involves the replacement of count values in the bladder on all projection views by data which are representative of the activity in surrounding structures. Reconstruction is then performed using the amended set of projection views. The method was tested by examining a group of 13 patients referred for investigation of avascular necrosis of the femoral head. Significant improvements in image quality were observed, particularly with respect to the level of artifact production, which increased the number of cases in which a confident and correct diagnosis was made.     

Displays for MR angiography

There are several MR imaging procedures that result in three-dimensional data of moving spins. One way to evaluate these data is a sequential observation of 2D slices. A more common and efficient approach is to retrospectively calculate two-dimensional projection images at different angles representing individual views of the tomographic volume. The display of different views from the same data set will allow a realistic visualization of the blood vessel anatomy.     

Utility of posterior oblique views in (99m)Tc-DMSA renal scintigraphy in children

OBJECTIVE: Procedure guidelines suggest that optimal (99m)Tc-dimercaptosuccinic acid (DMSA) planar scintigraphy of the kidney should include right and left posterior oblique views in addition to the posterior projection. However, in a small number of restless children, it is sometimes difficult to get 3 good-quality images. The aim of this study was to evaluate the prevalence of cases in which posterior oblique views were useful for interpreting (99m)Tc-DMSA renal scintigraphy. METHODS: Three nuclear medicine specialists were asked to interpret 40 (99m)Tc-DMSA renal scans twice, first on the basis of the posterior projection only and then by using the posterior and the right and left posterior oblique views. RESULTS: The oblique posterior views were considered useful by observers 1 and 2 for 4 kidneys and by observer 3 for 5 kidneys and were considered somewhat useful for up to 7 kidneys. The addition of oblique posterior views changed the interpretation on 5 occasions for observer 1, on 9 occasions for the observer 3, and on no occasion for observer 2. On average, therefore, changes in interpretation occurred for fewer than 6% of the kidneys. Moreover, no relationship was observed between the opinion of the clinicians that oblique views were useful and changes in the scintigraphic interpretations. CONCLUSION: Oblique views were found useful in only a few cases and, even in these cases, did not significantly modify the interpretations. Therefore, when restless children are being imaged, the focus should be on obtaining a good posterior projection, even at the price of not having oblique posterior views.     

Leg-length determination with biplanar CT scanograms

Computed tomography (CT) scanograms provide an accurate method for evaluation of leg-length discrepancy. Flexion of a leg may be missed on a single frontal projection, and the measurements obtained will be erroneously shortened. When performing CT sonography, lateral views of the limbs may be easily and rapidly obtained without having to change the position of the patient. This permits assessment of limb flexion.     

Evaluation of CT techniques for reducing artifacts in the presence of metallic orthopedic implants

Metallic intramedullary orthopedic implants generate artifacts that can markedly degrade transaxial CT images. The artifacts, typically seen as starburst streaking, result primarily from reconstructions involving missing projection data. Two approaches are clinically available to reduce the artifacts around orthopedic implants. These are (a) the imaging of implants with lower attenuation coefficients or smaller path lengths (less attenuating objects) and (b) the planar reformatting of image data. The sizing accuracy of these two approaches was quantified using phantoms and the efficacy using cadaveric femoral specimens. Results demonstrated that metal artifacts may be reduced and accurate bony dimensional data obtained.     

Radiography of the shoulder after Bristow repair

A radiologic follow-up of 30 shoulders in 29 patients operated upon according to the Bristow procedure is presented. Four projections of the shoulder were found necessary for adequate radiographic evaluation of the surgical results, a.p., lateral, oblique lateral and modified axial views. The two latter projections are appropriate for evaluation of the bony transplant and its relation to the anterior glenoid rim. Radiographic findings relating to bony union of the transplant and to the clinical results are discussed.