James H. Scatliff

Closed Spinal Dysraphism: Analysis of clinical radiological, and surgical findings in 104 consecutive patients

We reviewed 104 consecutive cases of closed dysraphism in patients seen at one institution between December 1984 and June 1987. All patients had myelographic studies, and 43 had associated CT examinations. Clinical and surgical findings (64 patients) were correlated with myelographic information. Twenty-three patients (22%) with clinical or plain film findings compatible with dysraphism had normal-appearing cords on conventional myelography, movement between supine and prone positions, and no lesions in the spinal canal. Cerebellar tonsillar ectopia (majority of tonsils between foramen magnum and C1) was found in 17 patients (16%). Six patients (6%) exhibited varying degrees of hydromyelia. In the supine position, CT-myelography of meningoceles, meningomyeloceles, or lipomeningomyeloceles may limit demonstration of the neural placode and nerve roots because of compression of the CSF-containing sac. In the decubitus position, CT scans improved demonstration of neural tissue-CSF space relationships. CT scans were useful in demonstrating anomalous paraspinal bones, diastematomyelia spurs, and spinal and sacral bone deficiency. Axial CT-myelography of intradural lipomas showed apparent neural tissue extension into the lipomas.

Varied CT appearance of aneurysms of the vein of Galen in infancy

SummaryAn aneurysm of the vein of Galen can have a varied CT appearance in infancy. The classical picture is a spherical posterior third ventricular mass with the density of circulating blood contiguous with a dilated straight sinus and with uniform contrast enhancement. With varying degrees of thrombosis of the aneurysm which may occur in late infancy, the mass can change in density and the dilated straight sinus disappear. With total thrombosis, a precontrast hyperdense rim develops with a low density center. The rim enhances but the low density center does not change with contrast infusion. Our experience in three patients with this spectrum of CT findings will be demonstrated and correlated with clinical findings and angiography.

From Röntgen to Magnetic Resonance Imaging The History of Medical Imaging

Medical imaging has advanced in remarkable ways since the discovery of x-rays 120 years ago. Todays radiologists can image the human body in intricate detail using computed tomography, magnetic resonance imaging, positron emission tomography, ultrasound, and various other modalities. Such technology allows for improved screening, diagnosis, and monitoring of disease, but it also comes with risks. Many imaging modalities expose patients to ionizing radiation, which potentially increases their risk of developing cancer in the future, and imaging may also be associated with possible allergic reactions or risks related to the use of intravenous contrast agents. In addition, the financial costs of imaging are taxing our health care system, and incidental findings can trigger anxiety and further testing. This issue of the NCMJ addresses the pros and cons of medical imaging and discusses in detail the following uses of medical imaging: screening for breast cancer with mammography, screening for osteoporosis and monitoring of bone mineral density with dual-energy x-ray absorptiometry, screening for congenital hip dysplasia in infants with ultrasound, and evaluation of various heart conditions with cardiac imaging. Together, these articles show the challenges that must be met as we seek to harness the power of todays imaging technologies, as well as the potential benefits that can be achieved when these hurdles are overcome.

Evolution of pyloric stenosis in the first week of life.

The evolution of antral spasm into classic infantile hypertrophic pyloric stenosis is described and illustrated in two patients.

Transcatheter Embolization of the Spleen for Control of Splenic Hemorrhage and In Situ Splenectomy: An Experimental Study Using Silicone Spheres

Silicone spheres were used for the transcatheter arterial embolization of dogs. This material successfully stops splenic hemorrhage in the lacerated organ, and also reduces spleen size. Use of silicone emboli to produce in situ splenectomy is not associated with morbidity or mortality in dogs. The authors discuss the value of using these methods in treating the high-surgical-risk patient.

Magnetic resonance imaging and spectroscopy of small ring-enhancing lesions using a rat glioma model.

RATIONALE AND OBJECTIVES.We sought to demonstrate the usefulness of proton and fluorine magnetic resonance spectroscopy (MRS) techniques in characterizing small ring enhancing lesions produced by experimental malignant gliomas. METHODS.The growth characteristics of a rat glioma model (RT2) were studied using contrast-enhanced magnetic resonance imaging scans of the tumors and histologic correlates obtained at various times. Changes in tumor metabolite levels were monitored on a serial basis using water-suppressed proton spectroscopy. The existence of tumor hypoxia was established using I9F MRS in combination with a fluorinated nitroimidazole and subsequently confirmed by immunohistochemical staining of tumor sections. RESULTS.Ring-enhancing lesions are produced by RT2 rat brain gliomas approximately 7 days after intracerebral implantation. Beginning at day 5, marked deviations in brain metabolite levels are observed on proton MR spectra. However, while the signal from the fluorinated nitroimidazole is first detected by 19F MRS at day 7, immunohistochemical staining of tissue sections reveals bound drug as early as day 5, when the first histologic signs of necrosis become apparent. CONCLUSIONS.Magnetic resonance imaging of RT2 rat brain glioma exhibits ring-enhancing characteristics similar to those observed in clinical studies. The appearance of the ring enhancement corresponds with the development of central necrosis and could serve as an indicator for rapid growth. Proton and fluorine MRS may be useful in confirming that a small ring-enhancing lesion represents an active tumor process early in its development.

Unusual abdominal manifestations of sacrococcygeal teratoma. A report of two cases.

The majority of sacrococcygeal tumours are visible or palpable buttock masses. Two cases of sacrococcygeal tumour are reported with prominent associated abdominal distension. The first case exhibited an unusually large intra-abdominal cystic component, as well as a large external cystic mass. Both cysts appeared to arise from a common origin on the sacrum. The abdominal enlargement in the second case was due to the presence of marked urinary ascites secondary to obstructive uropathy caused by the tumour. An incidental observation is offered concerning the recognition of destruction of the sacrum by this tumour. Non-visualization of osseous segments of the sacrum of neonates and infants may be due to defective development of the sacrum caused by the presence of a benign sacrococcygeal tumour, and not necessarily be associated with malignant transformation of this lesion.

The echogenic ependymal wall in intraventricular hemorrhage: Sonographic-pathologic correlation

Fifty-one patients with ultrasound diagnosis of intraventricular hemorrhage (Grades III and IV) were studied retrospectively for the presence of ependymal echogenicity. The sonographic findings were then correlated with histologic findings in six autopsy cases. Forty-one out of fifty-one newborns with intraventricular hemorrhage developed ependymal echogenicity on serial ultrasound studies. This echogenicity appeared approximately seven days after the hemorrhagic event and ulsually disappeared in about six weeks. Histologic examination revealed disruptions in the ependyma with proliferation and extension of subependymal glial cells onto the ventricular surface in those cases in which ependymal echogenicity was present at the time of death. This layer of proliferating subependymal glial cells may account for the ependymal echogenicity.

Computed tomography and spinal dysraphism: Clinical and phantom studies

SummaryTwo cases illustrating the value of CT in the assessment of spinal dysraphic tissue are presented. In one case, the configuration and origins of two osseous diastematomyelic spurs were shown well; in the second case, the CT recognition of a sacral lipoma led to air myelographic confirmation of the tumor and tethered cord. CT phantom studies indicated that dysraphic tissues, such as fat, cartilage, and fibrous tissue, are better identified and quantitated in the spinal canal when surrounded by air. Varying degrees of image degradation occur with water (simulating CSF) or metrizamide.

Pulmonary valve calcification

Abstract Two patients with radiographically demonstrable pulmonary valve calcification are reported on and the literature is reviewed.