Search PubMed⌕ Search

Biomedical subjects

S Walton

Publications and source records attributed to S Walton.

At least 91 records · Page 5Linked to original sources
PubMed1988

Roberts syndrome: antenatal ultrasound--a case report.

There is obvious confusion and overlap involving these various syndromes, i.e., Roberts syndrome, SC phocomelia, and TAR syndrome. However, the patient reported here seemed to exhibit the features of shortened upper extremities, clefting, and microbrachycephaly characteristic of Roberts syndrome. Antenatal detection of Roberts syndrome may be important in that early neonatal death can be expected. Other similar syndromes may have much longer survival. Cytogenetic abnormalities may be detected as well. It appears that routine ultrasonographic assessment of humerus length in addition to femur length may yield certain diagnoses that otherwise would be missed. The parents can be counselled concerning antenatal management including the possibility of not performing a cesarean section for some abnormal presentations.

Abnormalities, Multiple↗
PubMed1987

Stress induced right ventricular dysfunction: an indication of reversible right ventricular ischaemia.

Stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. This study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. This study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. Mean normal resting right ventricular ejection fraction (RVEF) was 0.40 (SD 0.118), and all normal subjects increased RVEF with stress (mean delta RVEF + 0.13 SD 0.099). Mean delta RVEF in the subjects with coronary artery disease was significantly lower at 0.00 (SD 0.080), but there was overlap between the two groups. The largest falls in RVEF were seen if the right coronary artery was occluded without retrograde filling. In this subgroup with the most severely compromised right ventricular perfusion (nine subjects), RVEF always fell with stress, and mean delta RVEF was -0.08 (SD 0.050). There was no significant correlation between delta LVEF and delta RVEF, implying that the right ventricular dysfunction was due to right ventricular ischaemia, rather than secondary to left ventricular dysfunction. Stress induced right ventricular ischaemia can therefore be detected readily by radionuclide ventriculography.

Adult↗
PubMed1987

Early imaging of the infarct.

Radionuclide techniques for the detection of acutely infarcted myocardium have been available for several years, but they are rarely used. Recent advances, such as the introduction of single-photon emission computed tomography and the introduction of novel radiopharmaceuticals, have suggested new clinical and research applications for them.

False Positive Reactions↗
PubMed1987

Antenatal detection of hypoplastic right ventricle with fetal M-mode echocardiography. A report of two cases.

Two cases of hypoplastic right ventricle were identified using fetal M-mode echocardiography. Follow-up studies and autopsies confirmed these findings. Both lesions were detected in women without antenatal risk factors. The indication for M-mode examination was an abnormal four-chambered view of the fetal heart obtained during ultrasound examination for common obstetric indications.

Adult↗
PubMed1986

Age and sex incidence of allergic contact dermatitis.

A retrospective study of patients patch tested between 1968 and 1970 was undertaken and case records of 200 patients with unequivocal positive patch tests were studied for age and sex distribution. There was an overall female preponderance (61%), with 2 peaks of incidence in the 10-20 and 40-50 year age groups in females, but only 1 peak of incidence in the 40-50 year age group in males. There was a steady decline in all sensitivities after the 6th decade of life in both sexes. Nickel sensitivity was more common in females (92%), whereas dichromate sensitivity predominated in males (64%). Of the 200 patients, only 5(2.5%) were atopics, all of whom were females.

Adolescent↗
PubMed1986

Antepartum ultrasonographic evaluation and management of placental chorioangioma. A case report.

Chorioangiomas are usually small and found by careful sectioning of the placenta. In recent years ultrasonography has been used in antenatal diagnosis. Multiple and large tumors (greater than 5 cm) are associated with increases in fetal morbidity and mortality. We treated a woman who had severe polyhydramnios and a large chorioangioma with vascular channels in the tumor confirmed by Doppler studies. Daily fetal breathing was used to monitor fetal well-being.

Adult↗
PubMed1985

Gated blood-pool emission tomography: a new technique for the investigation of cardiac structure and function.

ECG-gated single-photon emission-computed tomography of the intracardiac blood pool is a new technique that has not previously been widely applied. It involves the acquisition of ECG-gated images of the intracardiac blood pools labelled with sodium pertechnetate Tc 99m in 32 projections around the left-anterior hemithorax using a rotating gamma camera. From these images, tomographic sections are reconstructed orthogonal to the long axis of the left ventricle. The heart is therefore imaged three dimensionally, and more extensive information is obtained than in planar radionuclide ventriculography where imaging is usually restricted to only a single projection. Both structure and function can be studied, and the left-ventricular volume and ejection fraction, and wall motion are obtained. Of 50 patients studied, 7 cases are illustrated in order to show normal findings, examples of wall motion that were not shown by planar-contrast and radionuclide ventriculography, examples of the localisation of ventricular hypertrophy, and a comparison between blood-pool and 201TI myocardial tomography.

Adult↗
PubMed1985

Beckwith-Wiedemann syndrome: prenatal ultrasound diagnosis using standard kidney to abdominal circumference ratio.

Enlarged fetal kidneys are characteristic of more than one possible diagnosis. Though infantile polycystic kidney disease is probably the most well known entity and is associated with oligohydramnios, Beckwith-Wiedemann syndrome should be considered in the differential diagnosis especially if a normal or increased amount of amniotic fluid is present. The presence of an omphalocele with a normal karyotype should also arouse suspicion. This constellation of findings carries potential morbidity including macrosomia, fetal hypoglycemia, mental retardation, microcephaly, increased risk of subsequent neoplasia, and even neonatal death. Beckwith-Wiedemann syndrome may not be obvious in the newborn period.

Beckwith-Wiedemann Syndrome↗
PubMed1985

Left ventricular volume and ejection fraction determined by gated blood pool emission tomography.

Electrocardiogram gated single photon emission computed tomography of the intracardiac blood pools is a recent development that involves the acquisition of images in multiple projections after in vivo erythrocyte labelling with technetium-99m and reconstruction of these images into tomographic sections in any desired plane. The technique was used in 25 subjects to measure left ventricular volume, by summing the areas of the ventricle in each of the tomographic sections, and the results compared with those using a counts based (non-geometric) technique from planar radionuclide ventriculography. Endocardium was defined with the aid of a contour at 43% of maximum left ventricular counts, and this contour was validated for a left ventricular phantom. Correlation between tomographic and counts based left ventricular volume was close. Similarly, ejection fraction correlated well. The technique is therefore an accurate method for determining left ventricular volume and ejection fraction, avoiding the assumptions about shape made by other geometric methods.

Cardiac Output↗