Radiographic findings of spontaneous subluxation of the sternoclavicular joint.

Eight middle-aged women with spontaneous atraumatic subluxation of the sternoclavicular joint were evaluated with radiography and computed tomography. All patients were employed in occupations involving moderate to heavy physical labour, and no patients could recall a specific traumatic incident associated with onset of symptoms. In seven of the eight patients, the displacement of the medial clavicle was in a cranial direction; in four of the eight patients, there was an associated anterior subluxation, and in one patient, the subluxation was purely anterior. All five patients with an anterior component to the sternoclavicular subluxation had associated condensing osteitis of the clavicle. The sclerosis of the medial clavicle is possibly the result of chronic abrasion on the sternum and first costal cartilage in association with normal respiration and with upper extremity motion.

Mammographic follow-up of low-suspicion lesions: compliance rate and diagnostic yield.

All recommendations for mammographic follow-up of low-suspicion lesions seen at mammography during a 6-month period were reviewed to establish compliance rate and eventual outcome. One hundred forty-four of 2,650 mammograms (5%) showed minimal abnormalities that warranted short-term and periodic mammographic follow-up. Rates of compliance at 4 months and at 1, 2, and 3 years were 88%, 71%, 60%, and 47%, respectively. Progressive mammographic change was found in 10 patients, only one of whom had a carcinoma. It was concluded that mammographic follow-up of low-suspicion lesions is a reasonable alternative to surgical biopsy, although patient compliance remains a significant problem.

Fine needle aspiration biopsy of the breast. Influence of the number of passes and the sample size on the diagnostic yield.

The sensitivity of fine needle aspiration (FNA) biopsy of the breast as a function of the number of aspirations performed on any given lesion was investigated. Four separate aspirations each were performed on over 400 lesions of the breast, 93 of which yielded a cytologic diagnosis. The incremental diagnostic yields of each subsequent aspiration were tabulated. The first aspirate of the sequence gave the greatest yield, with smaller incremental yields on the second through the fourth aspirates. Benign and malignant lesions gave similar results, as did palpable and nonpalpable lesions (the latter being usually smaller in size). A mathematical extrapolation of the data indicates that three or four aspirations of any given lesion provide the optimal yield within the limits of practicality. This performance of multiple FNA biopsies is particularly important when the pathologist does not perform the biopsy, or is unable to assist in the immediate interpretation of the specimen to assess its adequacy.

Anterior cruciate ligament: oblique sagittal MR imaging.

Optimal visualization of the anterior cruciate ligament with magnetic resonance imaging requires oblique sagittal imaging planes. Between 10 degrees and 20 degrees of external rotation of the knee is considered ideal. While the knee may normally assume this amount of obliquity in the relaxed position, the orientation of the imaging plane is not guaranteed. Many imagers can perform oblique sagittal imaging, but the operator must set the proper degree of obliquity for the examination. A simple template was devised to facilitate this process, resulting in more consistently oriented imaging planes. The template can be reproduced by photocopying the diagram provided onto a transparency.

Paraffin tissue block radiography: adjunct to breast specimen radiography.

Radiography of specimens is an essential step in confirming excision of nonpalpable breast lesions. On occasion, however, the pathologist may not identify the lesion histologically. The authors report five cases in which suspicious microcalcifications were included in the excised tissue but were not identified by the pathologist. In all five, paraffin tissue block radiography enabled identification of the specific blocks containing the microcalcifications. The correct tissue blocks were then sectioned again, and the microcalcifications were identified histopathologically. In one case, the initial diagnosis of intraductal hyperplasia was changed to intraductal carcinoma with focal invasion. When the pathologist cannot identify the calcifications on initial histopathologic sections, this technique may assist in identification of the mammographic abnormality.

Computed arthrotomography of the shoulder: comparison of examinations made with internal and external rotation of the humerus.

We assessed the best positioning of the humerus for CT scans obtained after air-contrast shoulder arthrography by performing 54 examinations with both external and internal rotation of the humerus. Of the 30 abnormalities of the anterior portion of the labrum, 27 (90%) were identified on the scans obtained with the arm in internal rotation. The other three (10%) were shown best or solely on the scans obtained with the arm in external rotation. All 22 abnormalities of the anterior capsule were shown on the scans obtained with internal rotation. In no case were scans obtained in external rotation superior. Five posterior labral and capsule abnormalities were found; two of them were identified best or only on scans obtained with external rotation. The other three were shown equally well with the arm in either position. The results show that a modest (9%) increase in diagnostic yield can be expected when CT scans obtained with the arm in external rotation are added to studies performed solely with the arm internally rotated.

Direct coronal CT of the scaphoid bone.

A simple technique is described for the acquisition of coronal computed tomographic images of the wrist without positioning or immobilizing devices. The technique was used in four cases in which the radiographs were equivocal, to assess healing after scaphoid bone fracture or grafting. The greater resolution of the images provided more definitive information about healing.

Breast microcalcifications after lumpectomy and radiation therapy.

Ten of 152 (7%) consecutive breast cancer patients who underwent excisional biopsy and radiation therapy developed suspect microcalcifications at the biopsy site. All ten patients underwent reexcision. Seventeen other patients developed scattered, coarse, benign macrocalcifications that have remained stable as determined with mammographic follow-up. Of the ten patients who underwent reexcision, six had clusters of calcifications that were benign, and four had malignant calcifications. The morphologic appearance of the microcalcifications was similar in both malignant and benign disease, although the malignant calcifications tended to appear earlier than the benign ones. Three of the four patients with recurrent carcinoma had had calcifications in the original cancer. The mammographic features of the microcalcifications were not specific enough to distinguish recurrent malignancy from benign disease. Unless calcifications that occur in the breast after lumpectomy and radiation therapy have an unequivocally benign appearance (ie, scattered, round, homogeneous-appearing macrocalcifications), they should be viewed with suspicion and subjected to excisional biopsy.

Combination gel-inflatable mammary prosthesis: appearance at CT.

The combination gel-inflatable prosthesis is commonly used in breast reconstruction surgery following mastectomy for cancer. Since patients with this type of implant may be examined with computed tomography (CT) for possible pulmonary metastatic disease, recognition of the CT appearance is important in order to avoid the erroneous diagnosis of an infected prosthesis. A case is presented in which the CT appearance of a double-lumen prosthesis was misinterpreted as an infected prosthesis.

Evolution of skeletal hyperostoses caused by 13-cis-retinoic acid therapy.

Seven patients with disorders of keratinization (ichthyosis in six and Darier disease in one) were treated with 13-cis-retinoic acid and followed with annual skeletal surveys for 4-6 years. Six of the seven patients developed hyperostoses attributable to the retinoid therapy, manifested as multifocal entheseal calcifications or ossifications in both the axial and appendicular skeletons. In general, the earliest appearing hyperostoses became the largest with time, although in some instances, growth ceased at some foci and progressed at others. The severity of skeletal involvement was seemingly independent of dose, and may have been related to the patient's age at time of therapy. Involvement of the spine was earlier and more pronounced than the appendicular involvement, consisting of tiny hyperostoses arising from the corners of the vertebral bodies, primarily in the cervical and thoracic spine; these later matured into either discrete ossific spurs, or focal or flowing ossification of the anterior longitudinal ligament. The most prominent appendicular hyperostoses were at the tendinous or aponeurotic insertions on the calcaneus, were often unilateral or asymmetric when small, and became bilateral with time. Appendicular hyperostoses occurring at locations besides the calcanei were much smaller, often unilateral, and occurred later (generally between the third and fifth years of therapy). Our findings indicate that the earliest hyperostoses occurring in patients with 13-cis-retinoic acid occur in the spine and feet, and become the most prominent with time. Most appendicular hyperostoses occur later, are smaller, and frequently are asymmetric or unilateral.

Long-term radiographic follow-up after isotretinoin therapy.

We evaluated the effects of long- and short-term isotretinoin therapy on the skeletons of patients. Eight patients who were treated with isotretinoin for disorders of keratinization received frequent radiographic evaluations for 4 to 9 years. Seven patients developed multiple hyperostoses at the spine and extremities. Hyperostoses increased in size and number over the course of therapy, although relatively few sites were symptomatic. Hyperostoses typically developed first in the spine and later in the extremities, where both bilaterally symmetric and asymmetric involvement was observed. After 5 years of therapy one patient did not develop hyperostosis. In a group of nine patients who received a relatively high dose of isotretinoin in 1982 for the treatment of acne, two patients developed tiny, asymptomatic hyperostoses. One patient had hyperostoses 1 year after isotretinoin therapy, which remained unchanged 3 years later, whereas the other patient had one hyperostosis 4 years after therapy had been stopped. Although we suspect that these hyperostoses were retinoid induced, they should not be of concern for the patient needing routine isotretinoin therapy for the treatment of cystic acne.

Disappearing breast masses caused by compression during mammography.

Two cases are described in which a palpable mass and a nonpalpable mass disappeared during the performance of mammography. The disappearance is presumed to be caused by cyst rupture, resulting from the firm compression used to perform the examination. This occurrence can create confusing clinical and radiographic situations, and radiologists should be aware that occasional cyst rupture may occur.

Two-view specimen radiography in surgical biopsy of nonpalpable breast masses.

Nonpalpable, low-density, noncalcified lesions sometimes can be difficult to see on an initial specimen radiograph. In 57 consecutive wire localizations, 37 patients had obvious microcalcifications and did not require a second specimen radiograph. Twenty-six patients had nonpalpable, noncalcified lesions, and a second specimen radiograph was obtained in 24 of these. In four of these cases the initial specimen radiograph failed to show the suspected lesion, and a second specimen radiograph orthogonal to the original plane of orientation of the specimen showed the lesion to be contained within the biopsied material. Although it is seldom necessary to use this technique, it may obviate a second biopsy specimen as well as reduce operative time. We found that a second orthogonal specimen radiograph provided important information in 7% of cases.

Accessory breast tissue in the axilla: mammographic appearance.

Mammographic features of normal accessory axillary breast tissue were analyzed in 13 women, 54% of whom had positive findings on physical examination. Radiographically the accessory tissue resembled the remaining normal glandular tissue but was separate from it. The mean radiographic dimension of the accessory tissue, which was best seen on oblique or exaggerated craniocaudal views, was 3.9 cm. In most cases the accessory tissue was either bilateral or confined to the right side. When found on mammography, accessory axillary breast tissue should be recognized as a normal developmental variant rather than considered a pathologic lesion, although carcinoma can develop in the accessory tissue. A specific, radiography-aided diagnosis of accessory axillary breast tissue can eliminate unnecessary biopsy.

CT evaluation of mediastinal masses.

CT is an important modality for imaging mediastinal masses, and certain CT attenuation features (fat, calcium, or water attenuation, contrast enhancement) are well known to suggest specific diagnoses. In a series of 132 consecutive patients with tissue-proven mediastinal masses, these specific CT features were present in only 16. We evaluated the ability of CT to differentiate soft tissue mediastinal masses based on morphology and distribution of disease. Metastatic disease and lymphoma accounted for 69% of masses in this series, and CT could not generally differentiate them. However, CT was helpful in differential diagnosis in certain settings. CT demonstration of multiple mediastinal masses when conventional radiographs showed a single mass generally excluded diagnoses such as thymoma and teratoma. CT demonstration of a single middle mediastinal mass, frequently missed by conventional radiography, made metastatic disease a much more likely diagnosis than lymphoma. Finally, CT demonstration of certain ancillary findings strongly favored a diagnosis of lymphoma (axillary adenopathy) or metastatic disease (solitary pulmonary mass, focal liver lesions, bone lesions).

Failed first trimester pregnancy termination: uterine anomaly as etiologic factor.

Failure of first trimester pregnancy termination is an uncommon, although potentially serious complication of attempted therapeutic abortion. We report our experience in four patients with unsuspected congenital uterine anomalies in whom attempted pregnancy termination procedures failed to completely ablate the products of conception. When dilatation and curettage fails to produce embryonic tissue, sonography is indicated to exclude ectopic gestation or uterine anomaly. In patients who are known to have anomalous uteri, intraoperative real-time guidance may increase the success of pregnancy termination procedures and decrease the incidence of retained products of conception.