Transcalvarial primary lymphoma of bone. A report of two cases.

Primary lymphoma of bone is uncommon, and initial involvement of the calvarium is rare. We describe two cases originating as enlarging skull masses subsequently shown to involve the bony calvarium, extracranial soft tissues, and intracranial structures. Open biopsy revealed non-Hodgkin's lymphoma, large cell type, in both cases. A review of the pertinent literature follows.

Increased signal intensity of T1-weighted MR image of physiologic intracranial calcifications.

Among 1500 MR studies of the brain, performed during 1 year, there were six cases of physiologic calcifications (four in the falx cerebri, two in the deep gray matter) that revealed high signal intensity on T1- and variable signal on T2-weighted images. This phenomenon should be recognized and not confused with entities of clinical significance especially hemorrhage.

Intracavernous carotid artery aneurysm presenting as recurrent epistaxis.

Massive epistaxis from a leaking intracavernous carotid artery aneurysm is a rare occurrence. Such an unusual case is presented with appropriate imaging and a successful treatment program.

Case report 647: Benign osteoblastoma causing spinal cord compression and spastic paresis.

Osteoblastoma is an infrequent but important cause of pain in the back and neurological findings in children and young adults. Its diagnosis may be difficult and often delayed (in one series, 23% of patients had not been diagnosed after 2 years of symptoms). MRI may be useful to noninvasively image the lesion, its soft tissue and bony extent and its relationship, if any, to the spinal cord.

Cysticercosis mimicking brain neoplasm: MR and CT appearance.

The clinical and radiologic manifestation of neurocysticercosis are varied. Since the introduction of anticysticercal drugs, surgery is only rarely needed in treatment. During the last 2 years, we have encountered two patients with minimal symptomatology whose cerebral CT and magnetic resonance studies demonstrated single lesions consisting of an enhancing nodule surrounded by edema. There was ring enhancement of the nodule in one case and homogeneous enhancement in the other. Surgery was performed in both cases, because the primary consideration was brain tumor.

An alternative approach to nonpalpable breast biopsies.

Traditionally, when a negative specimen radiograph is obtained during biopsy of a nonpalpable breast lesion, immediate re-excision is performed in an attempt to successfully remove the lesion. Based on a retrospective study of the biopsy results of 792 nonpalpable breast lesions, the authors suggest delaying the re-excision, despite a negative specimen x-ray, until postoperative mammography confirms the persistence of the lesion. Utilization of this approach was associated with a comparably low incidence of missed lesions (3%) and had the added advantages of preserving breast tissue and decreasing operative time.

Needle localization of nonpalpable breast lesions with a portable dual-grid compression system. Work in progress.

A new device and a geometric algorithm facilitate consistent insertion of a needle tip into nonpalpable breast lesions on a single attempt. With the breast compressed by dual grid plates, two oblique exposures are taken. Three intersecting planes through the lesion referenced to the grid markings permit easy determination of the lesion coordinates. In initial trials for preoperative breast lesion localization in 11 patients, the needle tip was within the lesion in nine patients and was within 0.5 cm of the lesion in two patients. The results indicate that this system is very useful for accurate localization and needle aspiration of breast lesions.

MR imaging of intrasellar meningiomas simulating pituitary adenomas.

Over 3 1/2 years, 401 magnetic resonance studies were performed for suspected sellar-parasellar masses. Twenty-nine pituitary macroadenomas and 12 meningiomas were detected. Among the meningiomas there were three whose MR appearance simulated that of a pituitary tumor. In none of these cases was the diaphragma sellae visualized. Furthermore, in one case the prolactin level was elevated. A preoperative diagnosis of pituitary tumor resulted in an inappropriate surgical approach being used initially for its removal (transsphenoidal). Thus, nonvisualization of the diaphragma sellae and elevated prolactin levels do not exclude a nonpituitary origin of a sellar-parasellar tumor. Other methods for preoperative differentiation are discussed.

Limitations of mammography in the identification of noninfiltrating carcinoma of the breast.

A retrospective study of 321 patients who underwent localizing mammography and excisional biopsy of the breast from 1984 to 1985 was performed. The study was undertaken to refine selection criteria for biopsy in women with nonpalpable mammographic abnormalities by comparing mammographic features and impression with histologic findings. Twenty-eight of 36 (78 per cent) noninfiltrating carcinomas presented with microcalcifications alone; in contrast, 27 of 39 (69 per cent) infiltrating carcinomas presented with a mass alone. As the number of microcalcifications increased, so did the incidence of carcinoma. The size of the mass was not a guide for predicting carcinoma. Although only 11 of 75 carcinomas presented as a mass with microcalcifications, 11 of 21 calcified masses were carcinoma. There were no significant differences in the mammographic presentation between ductal and lobular carcinoma. The sensitivity of the mammographic impression was 48/75 (0.64), and the specificity was 221/246 (0.898). The false-positive rate was 25/73 (0.34), and the false-negative rate was 10/141 (0.07). From this study, we concluded 1, the incidence of noninfiltrating carcinoma was significantly higher and the incidence of positive nodes was significantly lower in nonpalpable abnormalities than in palpable masses; 2, noninfiltrating carcinomas were generally associated with microcalcifications alone, but infiltrating carcinomas were generally associated with a mass alone, and 3, the diagnostic accuracy of mammography was limited by under-interpretation of the subtler signs of noninfiltrating carcinoma and by over-interpretation of mammographic findings generally accepted as criteria for carcinoma.

Correlation of pathology observed in double contrast arthrotomography and arthroscopy of the shoulder.

Correlation of double contrast arthrotomography (DCAT) of the shoulder and arthroscopic surgery diagnostic results have been undertaken in 55 patients with persistent shoulder pain or involuntary shoulder instability. During the period March 1984 to December 1986, 55 patients underwent DCAT followed by videotaped diagnostic shoulder arthroscopy. The primary indication for DCAT was persistent pain in 36 patients and instability in 17 patients. DCAT was performed according to the method of El-Khoury and Albright, and all arthroscopies were performed in a similar fashion by the senior author (HJS). Both tests were reviewed separately, retrospectively, and their results were correlated. For combined (anterior and posterior) labral pathology, the sensitivity/specificity for the instability group was 0.91/0.91, respectively; sensitivity/specificity for the pain group was 0.63/0.94. DCAT accurately depicted the status of 76% of anterior labrums and 96% of posterior labrums. For complete rotator cuff tears, sensitivity/specificity was 1.0/0.94. The status of a complete rotator cuff tear was accurately depicted in 91% of patients. Partial rotator cuff tears were missed in 83% of patients by DCAT. The presence or absence of loose bodies was accurately represented by 96% of DCAT. Arthroscopy showed that 71% of the instability patients had a labral tear, compared with 44% of the pain patients. Rotator cuff pathology was present in 12% of instability patients and 42% of pain patients. These findings indicate that DCAT may be a conditionally reliable test in the diagnosis of shoulder instability. DCAT must be considered inconclusive, however, in the painful shoulder without instability. Its usefulness as a preoperative screening test is discussed, and a diagnostic algorithm is presented. DCAT does not equal the diagnostic accuracy of shoulder arthroscopy.

Magnetic resonance imaging and the diagnosis of avascular necrosis of the femoral head.

Low back pain and/or pain radiating to one or both lower limbs can result from causes other than intervertebral disc disease. Recently three patients presented with low back pain radiating down the legs. When CT examination of the lumbar spine proved unrewarding, magnetic resonance imaging (MRI) was performed. Avascular necrosis (AVN) of the femoral head was diagnosed and subsequently treated before femoral head collapse occurred. In patients with unexplained low back pain, AVN of the hip should be considered and ruled out by MRI, even if conventional plain films, polytomes, and radionuclide scans are negative. The early diagnosis of AVN of the femoral head may be critical in determining whether a surgical revascularization procedure might be successful in treatment, or replacement with an endoprosthesis will be necessary, if femoral head collapse has already occurred.

Laminated radiopaque enteroliths: diagnostic clues to intestinal pathology.

Laminated intestinal calculi were detected during radiographic evaluation of the abdomen in 14 adult patients. These enteroliths had developed in the distal ileum of 12 patients who had either a Meckel's diverticulum (four cases) or a variety of other lesions causing local stasis, including strictures due to Crohn's ileitis, ileocecal tuberculosis, radiation enteritis, and peritoneal adhesions. Only two patients had enteroliths in the colon proximal to strictures complicating ulcerative colitis. The clinical and radiological features of enterolithiasis as well as the mechanism of its formation are herein described.

Hodgkin's disease of spine: computed tomography and magnetic resonance imaging.

Early recognition of spinal block in a young man by magnetic resonance imaging and immediate surgical decompression of the spinal cord by removing the epidural mass, which proved to be Hodgkin's disease, was a determining factor in the complete neurologic recovery of the patient. Postoperative and postchemotherapy repeat magnetic resonance imaging showed complete resolution of the compressing mass. We believe that magnetic resonance imaging has a prominent role in the diagnosis and follow-up studies of spinal lesions without the inherent risks of other neurologic diagnostic procedures.

Separation of the distal humeral epiphysis in the neonate. A combined clinical and roentgenographic diagnosis.

Separation of the distal humeral epiphysis in the neonate or young child can be diagnosed confidently by combining roentgenographic and clinical information. Such diagnosis is critical, as two abnormalities included in the differential diagnosis--irreducible elbow dislocation and fracture to the lateral humeral condyle--often require open reduction, unlike distal humeral epiphyseal separation, which can be treated conservatively. We describe two patients and review the pertinent literature.

Computerized tomography of malignant pleural mesothelioma with spinal canal invasion.

A case malignant pleural mesothelioma is presented. The initial CT scan of the chest showed a left paraspinal pleural mass at T6-T7 level. Subsequently the mass was partially resected by a left thoracotomy. The patient later developed spinal cord findings, and a followup CT scan showed partial destruction of the twelfth dorsal vertebra and intraspinal tumor at T11-T12 level. This is only the second case reporting spinal cord compression by mesothelioma and the first documented by computed tomography.

Detection of pneumoencephaly secondary to mechanical ventilation in neonates.

Two newborn infants with respiratory distress syndrome developed massive systemic air embolisms and pneumoencephaly. These complications occurred during positive-pressure ventilation therapy. Intracranial gas was probably due to the rupture of cerebral vessels secondary to systemic gas embolism. The diagnostic features of plain radiographs, computed tomography, and ultrasonography in the evaluation of this unusual entity are described. The importance of early CT scans of the head is emphasized.