PubMed Health⌕ Search

Biomedical subjects

R Smart

Publications and source records attributed to R Smart.

At least 19 recordsLinked to original sources
PubMed1999

Outcomes of transrectal ultrasound scan of the prostate with sector biopsies for 323 New Zealand men with suspicion of prostate cancer.

AIMS: To assess the results and clinical outcomes of the first four years of transrectal ultrasound scanning (TRUS) with sector biopsies of the prostate, as the definitive second-line investigation for men with suspicion of prostate cancer, including comparability with subsequent information from histology of surgical specimens. METHODS: Information was collated from the author's ongoing surgical audit. TRUS and sector biopsies were carried out as a rooms procedure using a Toshiba Sono-Layer SSA-270A ultrasound machine with a PVL 725 RT transrectal probe and biopsy guide. Six or eight sector biopsies were taken with a Manan biopsy gun using 18 French gauge biopsy needles. Prophylactic ciprofloxacin and tinidazole were administered. Men with suspicion of prostate-specific antigen assay or digital rectal examination were considered for the investigation, especially if they were candidates for potentially curative treatments. RESULTS: Of 330 TRUS procedures performed on 323 men, 328 were done in rooms under local anaesthetic. The only significant complication was a transient bacteraemia in one patient not taking the antibiotics. Twenty men had prostate intraepithelial neoplasia or atypia, and 94 (29%) had cancer, of whom 24 (25%) had evidence of metastases. Curative treatment by radical prostatectomy or radiotherapy was attempted in 62 men (66%) and 28 are being managed by surveillance only. Comparisons with subsequent radical prostatectomy in 44 men showed that if only one TRUS biopsy core was involved with cancer (15 men), surgical margins were clear. For those with more cores involved (29 men), one-third (9 men) had positive margins or capsular perforation. The Gleason Score was different, more often higher, for 29 men by histology at radical prostatectomy compared to TRUS. Twenty-eight men had a subsequent transurethral resection of the prostate of which the histology resulted in management changes for ten of the 28, including three who were placed on surveillance and seven who underwent radical prostatectomy. CONCLUSIONS: TRUS and sector biopsy is a tolerable rooms procedure for men with suspician of prostate cancer. Complications are rare if prophylactic antibiotics are taken. The procedure provides information of sufficient quality to advise patients further. No defects in specificity were detected. Defects in sensitivity were demonstrated by comparison with later histology following transurethral resection. Therefore, men with benign results at TRUS need ongoing follow-up. TRUS histology tends to underestimate the extent of cancer present as determined by subsequent radical prostatectomy histology. When used with prostate-specific antigen and digital rectal examination, TRUS and sector biopsy is capable of detecting prostate cancer before it has metastasized, more reliably than if symptoms are awaited before diagnosis is attempted. It may also recognize forms of cancer of apparent low clinical significance which can be managed by surveillance.

Adenocarcinoma↗
PubMed1999

Broad clavicles in trisomy 8 mosaicism: a new sign.

Symmetrical clavicular widening was observed in a boy with mosaic trisomy for chromosome 8. This sign may be considered in conjunction with other clinical and radiographic features as an indication for chromosomal studies.

Adolescent↗
PubMed1999

An assessment of the sensitivity of the Cedars-Sinai quantitative gated SPECT software to changes in the reconstruction of the short-axis slices.

OBJECTIVE: This study assessed whether variations in count density, reconstruction filtering parameters and the short-axis orientation selected for reconstructions of myocardial short-axis slices significantly influenced the left ventricular ejection fraction (LVEF) calculated from a gated myocardial perfusion SPECT study. METHODS: The Cedars-Sinai quantitative gated SPECT software package was used to estimate the LVEF from gated 99mTc-sestamibi and 201TI gated SPECT studies in 20 patients. Oblique slices were reconstructed 12 times for each study, independently varying the filter cutoff and the orientation of the short axis each time. RESULTS: There were no clinically significant changes in the LVEF over the range of cutoff frequencies or orientation for either the 201TI or 99mTc-sestamibi studies. There was excellent agreement between the LVEF calculated from the 201TI and 99mTc-sestamibi studies on the same patients using the default filter (mean difference = 0.25% points). CONCLUSIONS: The Cedars-Sinai quantitative gated SPECT software package for parallel-hole collimators can be used with confidence to obtain an LVEF, and is not sensitive to variations in count density, filtering parameters or short-axis orientation.

Algorithms↗
PubMed1998

The role of latency in mandibular osteodistraction.

Even though osteodistraction has been well established in the extremities, the parameters used in craniofacial distraction have been essentially borrowed from orthopaedic experience. Latency is widely practised but its relevance has not been fully investigated. The purpose of this study was to establish the role of latency in mandibular distraction osteogenesis. Twenty-two growing Wethers sheep were allocated to four experimental groups. Six animals were allocated to each of Groups A, B and C and underwent bilateral mandibular corticotomies and attachment of an external lengthening device. Latent periods of 0, 4 and 7 days respectively were observed prior to beginning distraction. The distraction protocol consisted of a rate of 0.5 mm twice daily for 20 days, followed by a consolidation phase of 20 days after which the sheep were killed. Histology, bone densitometry and 3-point mechanical testing were performed on the harvested mandibles. Group D formed the control group (n = 4). Histologically, the distracted bone exhibited bone formation primarily via intramembranous ossification with scattered islands of cartilage. The regenerated bone had mechanical properties significantly weaker than the undistracted control group (P < 0.05), but between the experimental groups no statistically significant differences were demonstrable either in mechanical strength or DEXA density. These data indicate that a change in latency does not alter the properties of the regenerated bone in mandibular distraction osteogenesis and indeed no latent interval may be necessary at all in craniofacial distraction. This has implications for the duration of device fixation in distraction procedures.

Absorptiometry, Photon↗
PubMed1997

Twenty-year birth prevalence of Down syndrome in Cape Town, South Africa.

The 20-year birth prevalence of Down syndrome in Cape Town, South Africa, was determined. All cases delivered to mothers in Cape Town, plus terminations following prenatal diagnosis, between 1 January 1974 and 31 December 1993 were ascertained. There were 784 Down syndrome pregnancies, of which 95% were trisomies. The 32 terminations comprised 18.3% of the white, 5.8% of the coloured (mixed race) and 1.4% of the black cases. The overall prevalence rate was 1.49 per 1000 (white 1.88, coloured 1.54 and black 1.29 per 1000). Analysis for linear trends showed a significant decline in rates for the total population and for whites, a downward trend for coloureds, but no decline for blacks. Over the last 5-year period the prevalence rates in all three population groups were 1.3 per 1000. An increasing risk with advancing maternal age was confirmed, but no maternal age-specific differences in rates by race were demonstrated.

Abortion, Induced↗
PubMed1996

Estrogen replacement may be an alternative to parathyroid surgery for the treatment of osteoporosis in elderly postmenopausal women presenting with primary hyperparathyroidism: a preliminary report.

Parathyroid surgery is indicated in patients presenting with primary hyperparathyroidism (PHPT) and osteoporosis (defined as bone mineral density more than 2 standard deviations below normal). Many are elderly women with complex medical problems, either unwilling or considered unfit for surgery. Estrogen replacement therapy (ERT) may potentially be an alternative form of therapy in this group. We studied 15 consecutive postmenopausal women presenting with PHPT and osteoporosis. Group 1 comprised 5 women who elected to be treated with ERT (conjugated equine estrogen, 0.3-0.625 mg/day). The other 10 women underwent successful parathyroidectomy. These 10 patients were randomly subdivided into group 2 (5 patients who received calcitriol 0.25 micrograms b.i.d. for 12 months following surgery) and group 3 (5 patients who received elemental calcium 1 g/day for 12 months following surgery). Lumbar spine and femoral neck bone mineral density (BMD) were measured prior to and after 12 months of therapy, using a dual-energy X-ray absorptiometer (Lunar DPX-L). The three groups did not differ with respect to their ages (group mean 71.8 years), or baseline serum calcium (group mean 2.77 mmol/l), serum parathyroid hormone (group mean 11.0 pmol/l), lumbar spine BMD (group mean 0.93 g/cm2) and femoral neck BMD (group mean 0.73 g/cm2). Serum calcium normalized in all patients who underwent surgery and none developed hypoparathyroidism. A non-significant decrease in serum calcium was seen in patients treated with ERT only. Lumbar spine (+5.3% per year; 95% CI, 1.1% to 9.6%) and femoral neck BMD (+5.5% per year; 95% CI, -2.1% to 13.2%) increased significantly after 12 months of ERT (p < 0.001 compared with pre-therapy values). These increases in BMD did not differ significantly from those in patients who underwent successful parathyroidectomy followed by either calcitriol therapy or calcium replacement (lumbar spine BMD increase of +6.2% per year, 95% CI 3.1% to 9.4%; and femoral neck BMD increase of +3% per year, 95% CI 0 to 6%). In summary, increases in lumbar spine and femoral neck BMD occur following treatment of PHPT. ERT appeared as effective as parathyroidectomy (combined with either calcitriol or calcium supplements) for the treatment of osteoporosis in elderly postmenopausal women presenting with PHPT.

Aged↗
PubMed1995

Colon transit scintigraphy using oral indium-111-labeled DTPA. Can scan pattern predict final diagnosis?

Colon transit scintigraphy (CTS) was performed in 100 consecutive patients with idiopathic constipation using oral indium-111-labeled DTPA. Criteria were defined to allow classification of studies as normal, slow transit constipation (STC), or obstructed defecation (OD). Results were compared with final clinical diagnosis in 100 and findings of defecating proctography in 70. Of those with a scintigraphic diagnosis of STC, this was also the final diagnosis in 75% (33 of 44), and the scintigraphic diagnosis of OD was confirmed in 61% (17 of 28). Of 28 normal or equivocal scans, the final diagnosis was STC in only two (4%) but OD in 10 (21%). Fifty-four percent of patients with STC and 71% with OD had abnormal proctograms. The correlation between CTS and proctography was mediocre, occurring in 54% of patients. CTS has a valuable role in the diagnostic work-up of patients with idiopathic constipation.

Aged↗
PubMed1994

A variety of genetic mechanisms are associated with the Prader-Willi syndrome.

An extensive set of chromosome 15 DNA polymorphisms and densitometric analysis with four markers mapping to the Prader-Willi chromosome region (PWCR) of chromosome 15 have been used to characterize a cohort of 30 subjects with classical Prader-Willi syndrome (PWS). Molecular analysis enabled the classification of the PWS subjects into four groups: (A) 18 subjects (60%) had deletions of paternal 15q11-13 involving a common set of DNA markers. Two subjects had differently sized deletions, one larger and one smaller than the other cases. (B) Eight (27%) had maternal uniparental disomy for chromosome 15. (C) One (3%) had a marker chromosome carrying an extra copy of the PWCR. The marker chromosome was demonstrated to be of paternal origin and the two intact chromosomes were maternally derived. This case represents an apparent exception to the generally held view that PWS is associated with an absence of paternally inherited gene(s) located in the PWCR. (D) The remaining three cases (10%) had none of the above abnormalities. This last subgroup of patients has not previously been well characterized but could represent limited deletions not detectable with the markers used or abnormalities in the imprinting process. These cases represent potentially valuable resources to elucidate more precisely the fundamental disorders responsible for PWS.

Adolescent↗
PubMed1994

Thyrotoxic bone disease in women: a potentially reversible disorder.

OBJECTIVE: To measure changes in spinal and femoral neck bone mineral densities in patients treated for Graves thyrotoxicosis. DESIGN: Cohort study. SETTING: Tertiary care center. PATIENTS: Fifteen women with active Graves thyrotoxicosis. Six patients were premenopausal and nine were postmenopausal. All patients had evidence of thyrotoxicosis as indicated by a raised total serum thyroxine, suppressed serum thyroid-stimulating hormone, and an elevated technetium-99m pertechnetate thyroid scan. A control group of 15 healthy volunteers matched for age, sex, and menopausal status were followed during the same period. MEASUREMENTS: Bone mineral density was measured by dual-energy x-ray absorptiometry at baseline and after 12 months of antithyroid therapy when euthyroidism had been achieved. RESULTS: After 12 months of therapy, total serum thyroxine, total serum triiodothyronine, serum alkaline phosphatase, and serum bone Gla-protein activities had returned to normal in all patients (P < 0.001 for all comparison between initial and final biochemical measurements). During this interval, the mean lumbar spine bone mineral increased from an initial value of 1.01 g/cm2 to 1.07 g/cm2, an increase of 6.6% per year (95% CI, 3.6% to 9.6%) (P < 0.001 compared with controls). Increases in femoral neck (1.2%/y; CI, -2.1% to 4.5%; P = 0.2 compared with controls) and femoral trochanter bone mineral (3.2%/y; CI, 2.4% to 8.7%; P = 0.2 compared with controls) were not statistically significant. Using forced-entry multiple regression analysis, the severity of the thyrotoxicosis was independently associated with the percentage increment in lumbar spine bone mineral density after 12 months of antithyroid therapy. CONCLUSION: Effective treatment of Graves thyrotoxicosis was associated with increases in lumbar spine and femoral neck bone mineral. Although the changes in bone mineral were modest, our data suggest that thyrotoxic bone loss may be a reversible disorder.

Absorptiometry, Photon↗
PubMed1994

A comparative study of the safety and efficacy of dysprosium-165 hydroxide macro-aggregate and yttrium-90 silicate colloid in radiation synovectomy--a multicentre double blind clinical trial. Australian Dysprosium Trial Group.

The aim of our study was to compare the safety and efficacy of a new preparation, Dysprosium-165 Hydroxide Macroaggregate (165Dy) with Yttrium-90 Silicate (90Y) for radiation synovectomy of the knee in patients with RA and OA. A multicentre double blind clinical trial with subjects randomized to receive 165Dy or 90Y was undertaken in Sydney, Melbourne and Perth. Seventy knees of 59 patients were studied, using as clinical end point measurements, pain in the knee on walking, pain in the knee at rest and stiffness in the knee after rest. Cytogenetic damage, knee retention and extra-articular spread of the radionuclide to regional lymph nodes, liver, urine and blood were evaluated. There was no significant difference in clinical response in the two treatment groups for either RA or OA. Chromosomal changes occurred with equal frequency and the knee retention and extra-articular leakage of radiocolloids to regional lymph nodes and liver were comparable in the two groups. For radiation synovectomy of the knee, 165Dy is at least as safe and as effective as 90Y and has the advantage of a short half-life (2.334 h) and hence requires a shorter period of post-injection immobilization and hospitalization.

Aged↗
PubMed1993

Novel patterns of inheritance of genetic disease are illustrated by the Angelman syndrome.

OBJECTIVE: To characterise the molecular abnormalities present in a cohort of patients with the Angelman syndrome. METHODS: DNA samples from 10 patients with the Angelman syndrome were investigated with molecular probes. Family studies were performed by means of DNA polymorphism analysis and densitometric estimation of allele copy number to determine the underlying mutation and its parental origin. RESULTS: Nine probands were shown to have molecular (DNA) deletions involving chromosome 15q11-q13. Polymorphism analyses demonstrated that all deletions were maternal in origin. Five of the nine had normal karyotypes, with deletions only detected after DNA study. One patient had inherited both chromosomes 15 from her father. This represented an example of paternal uniparental disomy of chromosome 15. CONCLUSIONS: Development of the Angelman syndrome can result from either deletion of the maternally-derived copy of chromosome 15q11-q13 or the presence of two paternally derived copies of chromosome 15, that is, uniparental disomy. DNA testing allows the identification of deletions that are not seen on cytogenetic analysis and can provide additional information regarding the parental origin of the deletion. Uniparental disomy is most readily established by DNA studies.

Adolescent↗
PubMed1993

Re-evaluating the need for hospitalization following synovectomy using Yttrium-90 silicate.

In 51 patients treated with Yttrium-90 (Y-90) synovectomy for rheumatoid (inflammatory) arthritis (IA) and OA of the knee we found that decreased retained knee activity (RKA) and increased extra-articular activity in lymph nodes and liver are more likely to be found in IA than OA and following bilateral knee injections. Joint inflammation, as assessed by radionuclide blood pool scan but not by SF white cell count, correlates with decreased RKA and increased activity in lymph nodes. Intra-articular steroid had no significant effect on retention or extra-articular uptake. Strict hospital immobilization improves RKA of Y-90 in IA but not in OA. Y-90 synovectomy in OA shows good RKA and low extra-articular uptake. We recommend strict immobilization following Y-90 synovectomy, particularly in IA patients and/or those with high joint blood flow.

Adult↗
PubMed1993

Split-foot anomaly, microphthalmia, cleft-lip and cleft-palate, and mental retardation associated with a chromosome 6;13 translocation.

The split-hand/split-foot anomaly is a component of several disorders which may occur sporadically or be transmitted as autosomal dominant or autosomal recessive traits. We describe a severely mentally handicapped patient with ectrodactyly of both feet in association with extreme microphthalmia, central cleft-lip and palate and mental retardation. She has an apparent de novo 46,XX,t(6;13) (q21;q12) unbalanced translocation. Either of these breakpoints may be the locus for the ectrodactyly-ectodermal dysplasia-facial cleft (EEC) syndrome.

Abnormalities, Multiple↗
PubMed1992

Putative monosomy 21 in two patients: clinical findings and investigation using fluorescence in situ hybridization.

Complete monosomy 21 is claimed to be a rare chromosomal disorder in which the cytogenetic investigation is bedevilled by technical difficulties. We describe the disparate clinical features in two patients in whom an initial diagnosis of monosomy 21 was made by routine karyotyping. Fluorescence in situ hybridisation (FISH) confirmed a translocation of chromosome 21 material to the short arm of chromosome 5 and to the X chromosome, respectively. The usefulness of FISH in the investigation of subtle chromosomal rearrangements is hereby demonstrated. These findings also cast doubt on the existence of "pure" monosomy 21 as an entity, and suggest that partial monosomy 21 is a more likely occurrence.

Abnormalities, Multiple↗