Biomedical subjects

S D Wing

Publications and source records attributed to S D Wing.

16 recordsLinked to original sources

PubMed1979

Hemodynamic studies using a CT scanner.

New CT software programs allow rapid-sequence images to be obtained. During a period of 12 sec, multiple CT images can be produced, so that the progression of contrast flow at intervals of 1 sec or less can be followed. In addition, as many as 16 consecutive 3-sec scans can be performed, or arbitrary time intervals inserted between scans. The rapidity with which the contrast medium enters and leaves a specific tissue may be a valuable, non-invasive diagnostic tool in differentiating enhancing lesions. Other potential applications are mentioned.

Hemodynamics↗

PubMed1979

Complete and partial trisomy of different segments of chromosome 8: case reports and review.

This report describes some of the clinical, chromosomal and radiological findings in three unrelated patients with trisomy 8 mosaicism syndrome (T8ms), two first cousins with trisomy 8q and a patient with trisomy 8p. On the basis of the phenotypic and cytogenetic findings seen in our six patients and those noted in previous reports, we concur with Riccardi & Crandall (1978) that most physical malformations seen in T8ms are associated with trisomy for the long arm of chromosome 8.

Abnormalities, Multiple↗

PubMed1979

CT scans in Menkes disease.

The clinical courses and serial computerized tomography (CT) scans of four patients with Menkes disease are described. Although the initial clinical presentations were similar, head growth and serial CT scans showed striking individual differences. The CT scans varied from showing no abnormalities early in the disease to showing diffuse cortical atrophy, subdural accumulation of fluid, or multifocal areas of ischemic infarction. The pathologic findings in one patient showed only cerebral and cerebellar atrophy, whereas the findings in another patient showed areas of ischemic infarction, probably secondary to abnormal vessels. Menkes disease should be suspected in male infants with psychomotor deterioration and seizures, or when trauma is suspected from subdural hematoma and multiple fractures.

Brain↗

PubMed1979

Direct sagittal computed tomography in Graves' ophthalmopathy.

Standard axial transverse orbital computed tomography scans show the medial and lateral rectus muscles very well but section the superior and inferior rectus muscles obliquely. Determining enlargement of the superior and inferior recti in Graves' disease can therefore be difficult on axial transverse scans. We have obtained sagittal, coronal, and axial transverse orbital scans in a series of patients with Graves' ophthalmopathy and have compared the images in each plane. Direct sagittal and coronal scans were obtained without image regeneration from axial transverse sections by using a wide-aperture Varian body scanner and a special accessory table. Sagittal and coronal scans can demonstrate enlargement of the superior or inferior muscles even in cases in which the medial and lateral recti are normal. Since scans performed at approximately 20 degrees to the sagittal plane are parallel to the long axis of the orbit, they demonstrate orbital anatomy better than scans in the true sagittal plane.

Graves Disease↗

PubMed1979

A comparison of computed tomographic techniques in the diagnosis of Graves' ophthalmopathy.

We performed CT scans on 24 patients with clinically typical Graves' ophthalmopathy to compare the advantages of various scanning techniques. Scans were performed before and after intravenous contrast material infusion, and the contrast-enhancement of abnormal muscles was compared with that of known orbital tumors. Images were also obtained using 5-mm and 8-mm collimators, and the diagnostic value of these collimators was compared. Sagittal and coronal scans were performed in some of the cases, using a new direct technique for the sagittal plane. In general, the 5-mm collimators provided sharper definition of the ocular muscles and optic nerves. Contrast-enhancement alone was not helpful in differentiating enlarged muscles from orbital tumors because of the great overlap of attenuation coefficients. Sagittal and coronal images were helpful in confirming muscle enlargement suspected from axial scans, and were most useful in showing enlarged superior and/or inferior recti in cases with normal medial and lateral recti. The advantages of our method of obtaining sagittal scans through the long axis of the orbit and the potential application of this technique to orbital CT scanning are discussed.

Adult↗

PubMed1978

Low attenuation lesions in the midline posterior fossa: differential diagnosis.

A wide variety of cystic appearing or low attenuation lesions in the midline posterior fossa can so closely resemble one another as to render specific histologic diagnosis from CT scans alone fraught with error. Absorption coefficients often overlap and are too nonspecific to infer consistently accurate histologic diagnosis. It is virtually impossible to separate cystic from noncystic, benign from malignant, and neoplastic from non-neoplastic lesions by absorption coefficients alone.

Brain↗

PubMed1978

Direct sagittal scans in computed tomography of the orbits.

Sagittal scans of the brain and orbits can be performed with the Varian body scanner and an accessory table. These scans are obtained directly, with no image reconstruction from scans in other planes. A case of Graves' ophthalmopathy is presented which demonstrates the potential advantage of sagittal images in showing abnormalities near the orbital roof and floor. Sagittal scans complement coronal and axial views in CT evaluation of the orbits.

Graves Disease↗

PubMed1978

The evaluation of ependymal and subependymal lesions by cranial computed tomography.

Lesions of the ventricular ependyma and its derivatives can be visualized by CT scans, and their nature and extent can be determined. Generalized enhancement of the ependyma following the administration of intravenous contrast media can be seen with spendymoma, medulloblastoma, metastatic dysgerminoma, glioblastoma multiforme, and ependymitis. Localized ependymal enhancement can often be identified in the presence of acute ventriculitis, vascular anomalies or malformations, cerebral infarctions with luxury perfusion, and vascular neoplasms.

Adolescent↗

PubMed1978

Quantitative aspects of contrast enhancement in cranial computed tomography.

The temporal relationship of blood iodine levels to tumor enhancement in cranial computed tomography was studied in a series of patients. Both the bolus and biphasic techniques were evaluated. Peak tumor intensity may not develop immediately, but may be more pronounced on a 20-minute scan. The low-density centers seen in malignant gliomas show delayed enhancement. These low-density centers represent a second compartment which equilibrates with the intravascular and interstitial contrast material at a much slower rate. Patients with malignant gliomas can be scanned up to one hour following contrast injection without significant loss of information.

Blood-Brain Barrier↗

PubMed1978

Diagnosis of ascending transtentorial herniation by cranial computed tomography.

The secondary effects of large infratentorial masses may include ascending transtentorial herniation. Rostral displacement of the superior vermis through the tentorial incisura can be accurately detected by cranial computed tomography. Signs of early or impending upward herniation are compression and slight posterior flattening of the quadrigeminal plate cistern. Progressively more severe herniation produces amputation of the peritcetal cerebrospinal fluid diamond, leading to a triangle or "squared off" appearance of the confluent quadrigeminal and superior cerebellar cisterns. When the disorder is severe, the herniated vermis plugs the incisura, completely effacing these cisterns and flattening the posterior third ventricle. Obstructive hydrocephalus may also occur with moderate or severe herniation.

Aged↗

PubMed1978

The vertex scan: an important component of cranial computed tomography.

Physicians who monitor cranial computed tomography occasionally omit the most superior aspects of the brain and calvarium because of time limitations and overloaded scanning schedules. In addition, standardized CT reporting forms as well training literature distributed by some manufacturers support the concept that a complete CT series consists of three scan pairs. Omission of a vertex scan pair results in failure to visualize 10%-15% of the brain volume. We have reviewed the results of 2,000 consecutive CT studies to determine the number and variety of pathologic entities that would have been missed had a vertex scan not been obtained. The most significant or sole abnormality was present on the vertex scan alone in 3% of the cases. Examples are presented. A true vertex levels should be obtained in every routine CT examination.

Adult↗

PubMed1978

Coexisting pituitary adenomas and partially empty sellas.

seventeen cases of coexisting secreting pituitary adenomas and partially empty sellas are presented. The location of the cisternal invagination into the sella was not helpful in predicting the location of the tumor. In patients with endocrine indication of a secreting pituitary neoplasm, the finding of a partially empty sella should not contradict the diagnosis.

Adenoma↗

PubMed1978

Intracranial air on computerized tomography.

Intracranial gas may be epidural, subdural, subarachnoid, parenchymal, or intraventricular. Intracranial air can be easily diagnosed and its location correctly assessed by computerized tomography. Potentially serious complications of intracranial air, such as tension pneumocephalus, can be rapidly and accurately identified, facilitating appropriate clinical therapy.

Adolescent↗

PubMed1977

Computed tomography of angiographically occult cerebral vascular malformations.

Although some cerebral vascular malformations are angiographically occult, the correct diagnosis may be suggested by their appearance on computed tomography (CT). The authors advise caution in assuming that angiographically avascular lesions which show contrast enhancement on CT represent neoplasms rather than vascular malformations.

Adolescent↗

PubMed1977

Thin-section computed tomography in the evaluation of third ventricular colloid cysts.

The computed tomographic (CT) scan findings in 4 cases of third ventricular colloid cyst are presented, and the importance of thin-section CT in the evaluation of this lesion is discussed. Overlapping 8-mm sections are helpful in differentiating normal vasculature adjacent to the foramen of Monro from a third ventricular colloid cyst.

Cerebral Ventricles↗

PubMed1976

Contrast enhancement of cerebral infarcts in computed tomography.

Approximately 60% of cerebral infarcts between 1 and 4 weeks old may be enhanced by contrast material. A recent infarct can be missed if contrast material is not used; however, recent infarcts can also be partially obscured by the contrast medium, so that a precontrast scan is necessary. Infarcts, arteriovenous malformations, and gliomas may appear similar on the CT scan. Recent infarcts can have a significant mass effect (seen in 22% of cases), and their anatomical location and morphology may or may not be helpful in the differential diagnosis. Ipsilateral ventricular dilatation, homogeneous low-density areas, and sharp margins are usually found in older infarcts.

Adult↗