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Biomedical subjects

I Fogelman

Publications and source records attributed to I Fogelman.

At least 163 records · Page 9Linked to original sources
PubMed1993

Measurements of postmenopausal bone loss with a new contact ultrasound system.

Measurements of broadband ultrasonic attenuation (BUA) and velocity of ultrasound through the heel (heel velocity, HV) were performed with a Contact Ultrasonic Bone Analyzer (CUBA-Research model) in 229 women. The subjects consisted of 16 healthy young volunteers (Group 1, mean age 26 years), 170 healthy pre- and postmenopausal women (Group 2, mean age 53 years), and 43 osteoporotic women with radiographically defined vertebral crush fracture (Group 3, mean age 66 years). Subjects in Group 1 had 10 repeated measurements in a study of short-term precision. Women in Groups 2 and 3 also had dual X-ray absorptiometry (DXA) scans to measure lumbar spine and femoral neck bone mineral density (BMD). The BUA and HV measurements for all 229 women showed a significant correlation (r = 0.75, P < 0.001). The precision study on the subjects in Group 1 gave a root mean square coefficient of variation of 6.3% for BUA and 1.04% for HV. Linear regression analysis gave the following relationship between BUA and age for the 170 normal women in Group 2: BUA = 83.6-0.86 (age 40) dB/MHz (r = -0.31, P < 0.001, SEE = 16.3 dB/MHz). The relationship between HV and age was as follows: HV = 1614-2:3 (age 40) m/s (r = -0.33, P < 0.001, SEE = 42 m/s). Multivariate regression analysis showed that in addition to age, years since the menopause was also a significant factor in determining both BUA and HV.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Ultrasonic velocity measurements through the calcaneus: which velocity should be measured?

The assessment of skeletal integrity by the measurement of ultrasonic velocity through the calcaneus has only recently become widely available and is usually made in conjunction with the measurement of broadband ultrasonic attenuation. Using data obtained with a contact ultrasonic bone analyser (CUBA) system, this report examines whether ultrasonic studies of the heel require the measurement of true velocity of sound in the calcaneus (Vbone), or whether heel velocity (Vheel, defined as the mean velocity through bone and soft tissue) or time of flight velocity (Vtof, defined as the mean velocity between the two transducers) are adequate surrogates. The populations selected for study were 15 healthy young women (group 1, mean age 26 years), 231 healthy peri- and postmenopausal women (group 2, mean age 52 years) and 33 osteoporotic women with confirmed vertebral fracture (group 3, mean age 66 years). Precision was studied by performing 10 repeated scans on the subjects in group 1 and duplicate scans on 144 women randomly selected in groups 2 and 3. Precision was expressed as the percentage coefficient of variation (CV). Both precision studies yielded similar results. The precisions (and 5% to 95% ranges) for all groups combined were: Vbone 2.71% (1465-1809 m/s); Vheel, 1.10% (1511-1646 m/s): Vtof, 0.70% (1349-1425 m/s). Although the precision data suggest Vtof should be preferred, when the range of clinical values is taken into account the smaller CV is exactly cancelled by the narrower range.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Ablation of mediastinal parathyroid adenomas by superselective embolization of the internal mammary artery with alcohol.

Two young patients (20 and 21 years) had recurrent hyperparathyroidism following neck exploration. Non-invasive investigations failed to localize a parathyroid adenoma. In both cases selective catheterization of the internal mammary arteries combined with digital angiography demonstrated hypervascular mediastinal adenomas. Using a coaxial catheterization technique (Tracker 18 and 10), both branch arteries of the internal mammary supplying the adenoma were selectively catheterized. In one case absolute alcohol and the other a mixture of Lipiodol and absolute alcohol were used to effect the ablation. The procedures were uneventful and serum calcium levels have subsequently returned to within normal limits. The follow-up in these two cases extends to 2 1/2 years in one and 10 months in the other case.

Adenoma↗
PubMed1993

A study of the early and late 99technetium scintigraphic images and their relationship to symptoms in osteoarthritis of the hands.

Thirty-five patients with OA of the hands had an early and late phase isotope bone scan performed at entry and 1 yr later. Simultaneous assessment of symptoms was made by a visual analogue pain score (VAS) and a tender joint articular index (AI) and comparisons were made between the clinical and scintigraphic findings. Sixty-five percent of joints were classed as positive in the late phase compared to 17% in the early phase scan. Thirteen per cent of joints were positive only in the early phase and 49% only in the late phase. There was no significant overall change in either phase of the scan in 1 yr. The pattern of positive joints showed considerable symmetry and wrist involvement. There was a high degree of correlation between AI and the late phase scan but none with the early phase scan. VAS showed no correlation with the late phase scan but did correlate significantly with the early phase scan at 1 yr.

Aged↗
PubMed1993

SPECT imaging in the diagnosis of meniscal tears.

Sixty patients scheduled for arthroscopy of a knee because of suspected meniscal tears had preoperative planar and single photon emission computed tomography (SPECT) radionuclide scans. A crescentic pattern of uptake on the SPECT transaxial view was used as a criterion for diagnosing a tear of a meniscus. The sensitivity of the investigation was 77%, specificity 74%, negative predictive value (NPV) 65%, positive predictive value (PPV) 83%, and accuracy 76%. Tears of the posterior horn of the cartilage were also associated with intense focal uptake on the transaxial view as well as increased equilibrium activity in the adjacent femoral condyle. When these appearances were included as additional criteria the sensitivity rose to 90%, NPV 81%, and accuracy 84%. This study confirms the usefulness of SPECT imaging in identifying meniscal tears.

Adolescent↗
PubMed1993

Total body studies in normal British women using dual energy X-ray absorptiometry.

We report dual energy X-ray absorptiometry (DXA) studies of total body bone mineral and body composition performed in 111 normal caucasian women (aged 42-61). Conventional DXA scans of the lumbar spine and femoral neck were also obtained and each woman completed a detailed questionnaire. Significant correlations were found between total body BMD and BMD in the lumbar spine (r = 0.76) and femoral neck (r = 0.72). We present reference range data for BMD in the total body and in seven subregions of the skeleton. Multiple linear regressions of total body BMD and BMC on weight, height and age showed that the inclusion of height compared with weight and age alone was not statistically significant. The dependence of total body BMD on weight and age was: total body BMD (g cm-2) = 1.043 + 0.0042 x weight (kg) - 0.0039 x age (years) (R = 0.46, SEE = 0.074 g cm2). Body mass derived from DXA scans correlated well with weight measured on scales (r = 0.996, SEE = 0.77 kg). Body composition measurements agreed closely with % body fat estimated from skinfold measurements (r = 0.93), body fat mass estimated from a predictive equation based on weight, height and age (r = 0.91) and % body fat estimated from a predictive equation based on body mass index (r = 0.76). Study precision gave coefficients of variation of 0.6% for total body BMD and 0.7% for % body fat.

Absorptiometry, Photon↗
PubMed1993

Dual X-ray absorptiometry: a comparison between fan beam and pencil beam scans.

The recent introduction of dual X-ray absorptiometry (DXA) systems with fan beam instead of conventional pencil beam scanning geometry represents a significant technical advance in bone densitometry. This report describes phantom and in-vivo studies of the effect of the change in beam configuration on DXA measurements. Fan beam and pencil beam measurements acquired on one of the new generation scanners, the Hologic QDR-2000, were compared with scans performed on an earlier pencil beam model, the Hologic QDR-1000. The variation with height above the scanning table of fan beam measurements of an anthropomorphic spine phantom were: bone mineral content (BMC): -3.1% cm-1; projected area (AREA): -2.8% cm-1; bone mineral density (BMD): -0.2% cm-1. For pencil beam scans the magnitude of height variation was less than 0.1% cm-1. QDR-2000 fan and pencil beam scan results for 20 volunteers correlated closely with QDR-1000 pencil beam data (r = 0.966-0.998). For BMD measurements on the spine and hip, differences between fan and pencil beam data were consistent with the errors expected from measurement precision. For AREA and BMC data, however, larger differences were observed with individual deviations which correlated with body habitus of the subjects. Although the change from pencil to fan beam geometry significantly affected AREA and BMC data, the effect on the clinically more important BMD measurements was negligibly small.

Absorptiometry, Photon↗
PubMed1993

A comparison of reference bone mineral density measurements derived from two sources: referred and population based.

The construction of reference ranges for bone mineral density (BMD) is of importance when defining risk of osteoporosis in an individual. This study examined lumbar spine BMD from two different populations of women aged 40-69 years, both measured by dual X-ray absorptiometry (DXA) using Hologic QDR-1000 machines. Results were compared with the manufacturer's reference range. At one site (Centre 1) women were referred by general practitioners for BMD measurement to aid decisions regarding long term hormone replacement therapy (HRT). At the other (Centre 2), women were drawn from the age/sex register of a London general practice (population 11,000) and invited to attend a screening examination at their local hospital. The BMD for both groups did not differ significantly from the manufacturer's reference range. The BMD at Centre 1 was lower than Centre 2 by 0.0175 g cm-2 but this did not reach significance and after calibration of both DXA machines with a spine phantom the difference in BMD of the two groups was reduced to only 0.0034 g cm-2. Population based sampling carries no advantage over a GP referral based method for the construction of spinal BMD reference ranges. Although local BMD reference ranges may be required for sites outside the spine the comparable results in this study of the two UK reference ranges and those of the USA manufacturer suggest that local reference ranges for lumbar spine BMD using DXA may be unnecessary in the UK.

Absorptiometry, Photon↗
PubMed1993

Bone scintigraphy: Part 2. Orthopedic bone scanning.

Bone scanning provides a functional assessment of skeletal pathology not available with conventional radiography or special radiographic techniques such as CT and MRI. Bone scanning detects osteoblastic activity associated with many forms of orthopedic skeletal disease. Several of the more common orthopedic applications of bone scanning have been described above, while equally important topics such as prothesis loosening, avascular necrosis, and the reflex sympathetic dystrophy syndrome were not considered. Thus, for a great range of benign skeletal pathology, bone scanning can provide the orthopedic surgeon with practical information concerning the cause of the patient's pain, the true significance of otherwise questionable radiographic findings, the extent of disease and the results of orthopedic surgical treatment.

Arthrodesis↗
PubMed1992

Osteoporosis and chronic back pain: a study with single-photon emission computed tomography bone scintigraphy.

A group of 26 patients aged 47-81 years (average 67) with spinal osteoporosis and back pain for more than 6 months were investigated with planar and SPECT bone scintigraphy and anterior and lateral x-rays of the thoracolumbar spine. Abnormal activity on bone scintigraphy was found in all patients, of whom 22 had multiple lesions. A total of 17 (65%) patients had abnormal activity associated with collapsed vertebral bodies, 5 (19%) had degenerative disk disease, and 21 (81%) had facetal joint disease. Of 112 lesions identified by SPECT, 60 (54%) were localized to the apophyseal joints. Facetal lesions were commoner in those patients with more collapsed vertebrae, and 32 facetal lesions (54%) were associated with collapse of the vertebra immediately above or below. Bone scintigraphy findings suggest that in some individuals with osteoporosis and chronic back pain, collapse of the vertebral body or degenerative disk disease are causes of pain. However, the high frequency of increased apophyseal joint activity suggests that the facet joint may also be an important site of origin of pain in these individuals. Bone scintigraphy may identify a subgroup of osteoporotic patients with chronic back pain who would benefit from treatment to the facet joints.

Aged↗
PubMed1992

Measurements of broadband ultrasonic attenuation in the calcaneus in premenopausal and postmenopausal women.

We report a study of broadband ultrasonic attenuation (BUA) in the calcaneus in 248 women. Measurements were performed with a Walker-Sonix UBA-575 ultrasonic bone analyser. The populations studied were 15 healthy young volunteers (group 1, mean age 26 years), 200 healthy pre- and postmenopausal women (group 2, mean age 53 years) and 33 osteoporotic women with vertebral crush fractures (group 3, mean age 66 years). Subjects in group 1 each had 10 repeated measurements of their right heel. Duplicate BUA measurements in the right heel were performed in 96 subjects and bilateral scans in a further 87 women in group 2. The remaining 17 subjects in group 2 and those in group 3 had a single scan of the right heel. All women in groups 2 and 3 had dual X-ray absorptiometry (DXA) scans of the lumbar spine and femoral neck. The precision study on the women in group 1 gave a root mean square (RMS) coefficient of variation (CV) of 4.2%. Individual CV results showed statistically significant differences (range 1.3%-7.6%). Duplicate scans in subjects in group 2 gave a RMS CV of 4.6% while the bilateral measurements showed no significant difference between the two heels. Linear regression analysis gave the following relationship between BUA and age: BUA = 87.1 - 0.76 (Age - 40) dB/MHz (r = -0.31, p less than 0.001, SEE = 14.0 dB/MHz). Multivariate regression analysis showed that, in addition to age, years since the menopause was also a significant factor in predicting BUA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Gonadotropin-releasing hormone agonists and the skeleton.

OBJECTIVE: To review and evaluate published studies that have assessed the effect on the skeleton of treatment with gonadotropin-releasing hormone agonists (GnRH-a). The effects on bone biochemistry and bone density are presented. DATA IDENTIFICATION: Major studies reporting on bone and GnRH-a use were identified through Excerpta Medica and Medline searches. STUDY SELECTION: Those that have reported on GnRH-a treatment in patients where data relating to skeletal metabolism or bone density were obtained. RESULTS: Changes in bone biochemistry during GnRH-a therapy indicate that there is altered skeletal metabolism associated with GnRH-a use. The data on changes in bone density after a 6-month course of GnRH-a therapy generally indicate some bone loss. The magnitude of any detected change in bone density depends on the skeletal site assessed and the method of assessment. No significant bone loss has been documented in cortical bone; any bone loss occurring is usually associated with trabecular bone and is partially or completely reversible on withdrawal of GnRH-a treatment. CONCLUSIONS: A 6-month course of GnRH-a therapy may result in a small reduction in trabecular bone density that is partially or completely reversible on withdrawal of treatment. The magnitude of any persistent residual bone loss is unlikely to be of clinical relevance and the benefits of a single 6-month course of GnRH-a therapy should not be withheld on the basis of a possible effect on bone.

Bone Density↗
PubMed1992

Tamoxifen protects against steroid-induced bone loss.

As part of a clinical trial of adjuvant endocrine treatment in postmenopausal women with operable breast cancer serial bone density measurements have been performed by dual photon absorptiometry. Tamoxifen alone was given to 26 women, and 20 received additional prednisolone. By 24 months after entry there was no significant difference between mean bone density of the two groups, nor any significant change from baseline levels. There was a mean gain of 0.46% in the tamoxifen group and 1.95% in those given additional prednisolone. Thus the predicted steroid-induced bone loss was inhibited by tamoxifen. This may be of more general use in prevention of osteoporosis in patients requiring long-term steroid treatment.

Aged↗