Tumoricidal effects of sodium hexachloroiridate on an ascitic tumor in mice.

Sodium hexachloroiridate injected 1 day after i.p. injection of 10(6) mouse ovarian tumor cells prevents the appearance of ascitic tumors in mice. Mice given injections of tumor cells all die at 20 to 30 days after tumor injection. Mice treated with sodium hexachloroiridate after tumor injection either have significant prolongation of life span without ascites or show no evidence of cancer even up to 7 months after tumor injection.

Quantitative bone single-photon emission computed tomography for prediction of pain relief in metastatic bone disease treated with rhenium-186 etidronate.

PURPOSE: To calculate radiation doses of rhenium-186 ((186)Re) etidronate in painful bone metastases using quantitative bone single-photon emission computed tomography (SPECT) and to determine the threshold dose for predicting pain relief. We also wanted to determine whether technetium-99m ((99m)Tc) methylene diphosphonate (MDP) concentrations predict radiation doses of (186)Re etidronate in painful lesions. MATERIALS AND METHODS: Forty-eight patients with breast and prostate cancer were evaluated. Patients received therapeutic doses of (186)Re etidronate. The area under the pain over time curve (AUPC) was measured for 8 weeks after treatment. Response was calculated as the percentage of change in AUPC. Quantitative bone SPECT (QBS)-measured concentration of (186)Re etidronate was used for calculating radiation doses. Receiver operating characteristics curve analysis determined the radiation dose threshold that best separated responders from nonresponders. SPECT-measured concentration of (186)Re etidronate in the urinary bladder was correlated with its concentration in the voided urine. Concentration of (99m)Tc MDP was compared with radiation doses to painful metastases. RESULTS: The radiation dose threshold was 2.10 Gy. For a decrease of 50% in the AUPC, the positive predictive value (PPV) of this value was 75% and the negative predictive value (NPV) was 88%. For a decrease in pain of 33%, the PPV was 84% and the NPV was 81%. In prostate cancer patients only, the PPV was 81% and the NPV was 92%. The correlation between in vivo/in vitro measured urine concentration was 0.90. The correlation between (99m)Tc MDP concentration and radiation doses of (186)Re etidronate was 0.92. CONCLUSION: QBS-measured radiation doses of (186)Re etidronate in painful metastases are a good predictor of pain relief. Bone SPECT using (99m)Tc MDP predicts radiation doses delivered by (186)Re etidronate.

Single-photon emission computed tomography quantitation of gallium citrate uptake for the differentiation of lymphoma from benign hilar uptake.

PURPOSE: To assess the role of quantitative gallium citrate (Ga 67) single-photon emission computed tomography (SPECT) in differentiating lymphoma from benign hilar uptake, concentrations of Ga 67 in 29 sites of documented lymphoma and in 75 benign lesions were compared. PATIENTS AND METHODS: One hundred seven thoracic Ga 67 SPECT studies obtained in 101 consecutive lymphoma patients were reviewed. Fifty-nine studies detected Ga 67 uptake in the hilar and or mediastinal regions. Forty-eight studies showed no such abnormality. The concentration of Ga 67 in the thoracic lesions was measured using a quantitative SPECT technique and its nature was determined by correlation with computed tomographic (CT) scans and follow-up evaluation of the sites. RESULTS: In 20 of 59 abnormal studies (34%), there was lymphoma in the hilar and or mediastinal regions. In the remaining 39 abnormal studies (66%), Ga 67 uptake was benign. There were 29 sites of lymphoma and 75 benign lesions. The concentration of Ga 67 in lymphoma was significantly higher than in benign hilar uptake (13.2 +/- 5.4 %ID/mL x 10(-3) v 5.6 +/- 1.5 % injected dose (ID)/mL x 10(-3); P < .001). A concentration value of 8.3 %ID/mL x 10(-3) was found to best separate lymphoma and benign uptake, with a sensitivity of 90%, a specificity of 93%, a positive predictive value of 84%, and a negative predictive value of 96%. CONCLUSION: Lymphoma and benign hilar uptake differ significantly in their concentration of Ga 67. The present study shows that quantitative Ga-67 SPECT reliably differentiates lymphoma and benign uptake.

Utility of gallium-67 scintigraphy in low-grade non-Hodgkin's lymphoma.

PURPOSE: Low-grade non-Hodgkin's lymphoma (LGNHL) has traditionally been considered non-gallium-avid. The sensitivity of gallium 67 (67Ga) scintigraphy when using modern equipment and techniques in patients with LGNHL was investigated. MATERIALS AND METHODS: Fifty-seven consecutive patients with LGNHL underwent 67Ga scintigraphy at initial presentation (n = 40), when tumor progression occurred during treatment (n = 3), and at suspected disease recurrence after continuous clinical remission (CCR) (n = 14). Planar and tomographic images were obtained with either a very large field-of-view or a dual-head digital camera. Of 45 patients with Ga-avid LGNHL, 30 underwent 93 follow-up scans (one to six studies per patient). Scan findings were correlated with clinical and computed tomographic (CT) findings and with patient outcomes. RESULTS: 67Ga scintigraphy was positive in 45 of 57 patients (sensitivity, 79%) and in 113 of 164 disease sites (sensitivity, 69%). The sensitivity was higher in the more common types of LGNHL: follicular, predominantly small cleaved cell (FSC), and follicular, mixed small cleaved and large cell (FM) (84% and 91% in patients and 72% and 71% in disease sites, respectively). Sensitivity was lower in patients with mucosa-associated lymphoid tissue lymphoma (MALT) and small lymphocytic lymphoma (SL). Among 28 patients with disease recurrence after CCR (14 with and 14 without baseline studies), 67Ga scan was positive in 25, for a sensitivity of 89% for detection of disease recurrence. CONCLUSION: When modern technology is used, 67Ga scintigraphy has good sensitivity in patients with LGNHL. It therefore can be used to monitor response to therapy and to provide early detection of disease recurrence in these patients.

Intracoronary thallium-201 scintigraphy after thrombolytic therapy for acute myocardial infarction compared with 10 and 100 day intravenous thallium-201 scintigraphy.

Thallium-201 imaging has been utilized to estimate myocardial salvage after thrombolytic therapy for acute myocardial infarction. However, results from recent animal studies have suggested that as a result of reactive hyperemia and delayed necrosis, thallium-201 imaging may overestimate myocardial salvage. To determine whether early overestimation of salvage occurs in humans, intracoronary thallium-201 scans 1 hour after thrombolytic therapy were compared with intravenous thallium-201 scans obtained approximately 10 and 100 days after myocardial infarction in 29 patients. In 10 patients with angiographic evidence of coronary reperfusion, immediate improvement in thallium defects and no interim clinical events, there was no change in imaging in the follow-up studies. Of nine patients with coronary reperfusion but no initial improvement of perfusion defects, none showed worsening of defects in the follow-up images. Six of these patients demonstrated subsequent improvement at either 10 or 100 days after infarction. Seven of 10 patients with neither early evidence of reperfusion nor improvement in perfusion defects had improvement of infarct-related perfusion defects, and none showed worsening. In conclusion, serial scanning at 10 and 100 days after infarction in patients with no subsequent clinical events showed no worsening of the perfusion image compared with images obtained in acute studies. Therefore, there is no evidence that thallium-201 imaging performed early in patients with acute myocardial infarction overestimates improvement.

Left ventricular pressure-volume diagrams and end-systolic pressure-volume relations in human beings.

Assessment of left ventricular pressure-volume relations serially in response to altered loading conditions and heart rate has been difficult to achieve with contrast ventriculography. Accordingly, to study changing pressure-volume relations during altered loading and heart rate, left ventricular pressure and radionuclide absolute volume curves (obtained using a counts-based method with attenuation factor corrections) were recorded in 20 patients. Ventricular pressure and radionuclide volume curves were digitized and synchronized to end-diastole, and pressure-volume plots were subsequently constructed from 32 pressure-volume coordinates throughout the cardiac cycle. In all patients, the correlation between radionuclide absolute volumes and angiographic ventricular volumes was r = 0.92. In 10 patients in whom both radionuclide and angiographic pressure-volume diagrams were constructed, the agreement between the two methods was excellent. With this method, end-systolic pressure-volume relations were examined during altered left ventricular loading conditions, pacing-induced incremental increases in heart rate and pacing-induced ischemia. Using pharmacologically induced changes in left ventricular loading conditions, the slope and volume intercept of the end-systolic pressure-volume line could be calculated as a means of assessing basal contractility. During pacing-induced tachycardia, the slope and volume intercept of the end-systolic pressure-volume line could be calculated to quantify the Treppe effect and assess negative inotropic changes secondary to ischemia. This study supports the validity of using serial recordings of left ventricular pressure and radionuclide volumes to assess left ventricular pressure-volume relations, and indicates that this approach may be useful in the analysis of end-systolic pressure-volume relations in patients.

The pacing stress test reexamined: correlation of pacing-induced hemodynamic changes with the amount of myocardium at risk.

To assess the relation between extent of ischemia and the magnitude of hemodynamic changes, 25 patients (5 with normal coronary arteries and 20 with significant coronary obstructive disease) were studied with rapid atrial pacing and thallium scintigraphy at the time of cardiac catheterization. Hemodynamic variables were measured before, during and after maximal pacing. Thallium was injected intravenously during maximal pacing and scans in three standard views were obtained immediately in the catheterization laboratory, with delayed scans obtained 4 hours after the cessation of pacing. The three thallium scans were each subdivided into five segments, and a thallium score was obtained on the basis of the total number of segments that were hypoperfused. Each patient was assigned a total thallium score corresponding to thallium defects at maximal pacing, as well as a redistributed thallium score corresponding to the difference between thallium score at maximal pacing and that 4 hours later. With pacing, patients with normal coronary arteries demonstrated no significant change in baseline hemodynamic variables, whereas patients with coronary artery disease exhibited a decrease in cardiac index, an increase in systemic vascular resistance, a widening of arteriovenous oxygen difference, an increase in pulmonary capillary wedge pressure and mean pulmonary artery pressure during maximal pacing and an increase in left ventricular end-diastolic pressure immediately after pacing. There was a significant correlation (Spearman rank r = 0.64, p less than 0.01) between redistributed thallium score and an increase in left ventricular end-diastolic pressure in the postpacing period. Moreover, there was an even higher correlation (Spearman rank r = 0.90, p less than 0.001) between total thallium score and the postpacing increase in end-diastolic pressure. It is concluded that in patients with coronary artery disease the magnitude of pacing-induced hemodynamic changes reflects both the amount of myocardial tissue at ischemic jeopardy and the total mass of hypoperfused myocardium during maximal pacing stress.

The pacing stress test: thallium-201 myocardial imaging after atrial pacing. Diagnostic value in detecting coronary artery disease compared with exercise testing.

Many patients suspected of having coronary artery disease are unable to undergo adequate exercise testing. An alternate stress, pacing tachycardia, has been shown to produce electrocardiographic changes that are as sensitive and specific as those observed during exercise testing. To compare thallium-201 imaging after atrial pacing stress with thallium imaging after exercise stress, 22 patients undergoing cardiac catheterization were studied with both standard exercise thallium imaging and pacing thallium imaging. Positive ischemic electrocardiographic changes (greater than 1 mm ST segment depression) were noted in 11 of 16 patients with coronary artery disease during exercise, and in 15 of the 16 patients during atrial pacing. One of six patients with normal or trivial coronary artery disease had a positive electrocardiogram with each test. Exercise thallium imaging was positive in 13 of 16 patients with coronary artery disease compared with 15 of 16 patients during atrial pacing. Three of six patients without coronary artery disease had a positive scan with exercise testing, and two of these same patients developed a positive scan with atrial pacing. Of those patients with coronary artery disease and an abnormal scan, 85% showed redistribution with exercise testing compared with 87% during atrial pacing. Segment by segment comparison of thallium imaging after either atrial pacing or exercise showed that there was a good correlation of the location and severity of the thallium defects (r = 0.83, p = 0.0001, Spearman rank correlation). It is concluded that the location and presence of both fixed and transient thallium defects after atrial pacing are closely correlated with the findings after exercise testing.(ABSTRACT TRUNCATED AT 250 WORDS)

Natural evolution of cardiac function, cardiac pathology and antimyosin scan in a murine myocarditis model.

Serial technetium-99m radionuclide ventriculograms, indium-111 antimyosin antibody scans and tissue biodistribution studies were performed in C3H/He mice with experimentally induced viral encephalomyocarditis and the results were compared with pathologic assessments of myocardial necrosis. Postinfection ejection fraction decreased on days 10 (20.7 +/- 5.5%, n = 6), 20 (18.6 +/- 15.2%, n = 5), 30 (18.5 +/- 7.7%, n = 5) and 150 (30.0 +/- 18.7, n = 6) (p less than 0.001) in comparison with that in uninfected control mice (63.3 +/- 3.1%, n = 6). In the same group of animals, indium-111 antimyosin antibody scans showed intense positive myocardial accumulation on day 10 (in six of six mice) and only slight accumulation on day 20 (in one of five mice). In the chronic stage, two of five mice on day 30 and two of six mice on day 150 still showed positive uptake. The antimyosin scan myocardium to lung uptake ratio (expressed as mean count density [mean counts/pixel of the region] ratio) increased greatly on day 10 (p less than 0.001 versus values in uninfected control mice) but not subsequently. Biodistribution studies of the indium-111 antimyosin antibody showed that the heart to blood count ratio was significantly higher on day 10 (p less than 0.001 versus values in control mice) but not on days 20, 30 and 150. Pathologic examination showed active and ongoing severe myocardial necrosis with dilated ventricles on day 10. On day 20, there was less active necrosis and healing had appeared to begin. On days 30 and 150, myocardial fibrosis increased.(ABSTRACT TRUNCATED AT 250 WORDS)

The spleen-lung interface as diagnostic information.

Left anterior, lateral, and posterior views on 50 consecutive RES-lung scams were examined. Normal patients had continuity of activity between the left lung and the spleen on all three views. Patients with subphrenic abscess or large left pleural effusions showed no continuity between lung and spleen activity on any view, while other abnormalities, most commonly cardiomegaly, accounted for lack of lung-spleen continuity on the anterior view only. It is suggested that in all combined RES-lung studies, the left side be examined as well as the right for abnormalities adjacent to the left diaphragm.

Scintigraphy of hepatic hemangiomas: the value of Tc-99m-labeled red blood cells: concise communication.

Fourteen patients with hepatic hemangiomas were evaluated by Tc-99m colloid scintigraphy and Tc-99m RBC angiography, including flow studies and early and delayed static studies. On colloid scintigraphy, the liver appeared enlarged, with single or multiple focal defects. During the flow and early static Tc-99m RBC studies, the lesions showed poor perfusion and were filled only partially or not at all. Delayed Tc-99m RBC studies demonstrated the whole extent of the lesion and all the lesions when multiple hemangiomas were present. A flow study showing decreased perfusion and a late blood-pool study showing increased local blood volume appear characteristic of hemangiomas. Liver biopsy should not be attempted in such cases.

SPECT quantitation of cobalt-57 bleomycin delivery to human brain tumors.

A newly developed and validated noninvasive quantitative SPECT method was used to measure the in vivo uptake of [57Co]bleomycin (Co-bleo) in 13 human brain tumors and the uptake of [99mTc]glucoheptonate (GH) in 23 brain tumors. Significant differences in tumor uptake were found. The tumor concentration over time, the tumor to blood radio at 30 min and the tumor cumulative concentration of radioactivity showed marked differences even between tumors with the same histology. Only a weak correlation was found between tumor concentration of Co-bleo and of GH. Therefore a simple imaging agent such as GH cannot, at the present time, serve as an indicator of individual tumor uptake and further experience with other agents is still necessary. Contrary to the generally held view, no correlation was found between the concentration of drug in the blood and its tumor concentration. It is suggested therefore that the level of a drug in the blood cannot be used as a criterion of the amount that will penetrate the tumor. Direct SPECT measurement of the concentration of the drug in the tumor itself should be performed. The bioavailability of a drug is critical in order for it to exert it tumoricidal effect. The results, showing marked differences in uptake between brain tumors, suggest that before chemotherapy is administered, uptake of the chemotherapeutic drug in the individual tumor to be treated should be assessed and comparisons should be made between the uptake of a series of drugs to determine which drug would be most efficacious on the basis of its uptake as well as its tumor cell killing potential.

Stress fractures associated with osteosarcoma of the lower limb.

Three patients with osteosarcoma of the femur developed abnormal radiopharmaceutical uptake in the bones of the contralateral leg. This uptake was not due to metastases. The histology in one patient, the form of the lesion and the disappearance of the abnormal uptake without treatment in the other two, indicated that the uptake was probably due to stress fractures. Changes in weight bearing and walking in the normal leg as a result of the osteosarcoma in the other leg could have been the cause of the stress fractures. It should be recognized that new abnormal uptake on bone scintigraphy in patients with osteosarcoma of the leg may not necessarily indicate metastasis. It may be caused by a stress fracture and disappears after rest.

In vivo SPECT quantitation of bone metabolism in hyperparathyroidism and thyrotoxicosis.

Bone metabolism was assessed in vivo and noninvasively using quantitative SPECT. The effect of endocrine abnormalities on bone metabolism was studied in 27 patients with primary hyperparathyroidism (HPT) and 12 patients with thyrotoxicosis (TTX). Quantitative bone scintigraphy (QBS) values of 99mTc-MDP uptake were compared to normal values matched for sex and age. Bones with significantly increased QBS values indicating increased bone metabolism were identified in the two patient groups. Fifty-one percent of the bones in patients with HPT and 78% in patients with TTX showed significantly increased QBS values. Increase in bone metabolism was highest in the femoral shaft. Seven patients with HPT and five with TTX were successfully treated. Six patients with HPT and four patients with TTX showed significant decrease of bone metabolism with normal QBS values after three months. The results indicate that QBS can be used to evaluate bone metabolism and its response to treatment in individual bones in patients with endocrine abnormalities.

Local and systemic effects of radiation on bone metabolism measured by quantitative SPECT.

Quantitative bone scintigraphy (QBS), which measures 99mTc-MDP uptake expressed as percent of injected dose per cc, indicates bone metabolism. It is measured in the bones of patients before and after radiation treatment and then compared to normal controls. QBS was performed in a group of 22 normal individuals and was measured twice, 2-10 mo (mean 4.9) apart. There was no significant difference between the two measurements. QBS was performed also in 28 patients before, immediately after and at certain time intervals after radiation therapy for cancer. Both the irradiated and the nonirradiated bones showed significant decreases in bone metabolism at 2-18 mo (mean 8.8) after irradiation. In addition, increases and decreases of 99mTc-MDP uptake were similar in the irradiated and in the nonirradiated bones, and there were significant correlations of the QBS values in the different bones of each individual patient. The etiology of the changes in bone metabolism in the nonirradiated bones is not yet fully understood, but it appears to be the result of a systemic effect of radiation.

Quantitative bone SPECT in young males with delayed puberty and hypogonadism: implications for treatment of low bone mineral density.

UNLABELLED: Constitutional delayed puberty (DP) and idiopathic hypogonadotropic hypogonadism (IHH) lead to osteoporosis in adult men. We were interested in whether response to treatment of these conditions by testosterone could be predicted by in vivo quantitative bone SPECT (QBS) measurement of bone turnover and whether testosterone administration affects bone mineral density (BMD) in these subjects. METHODS: In vivo QBS and BMD measurements were performed in the lumbar spine (LS) and femoral neck (FN) of 29 young men with DP and 16 young men with IHH. In vivo QBS and BMD values in these patients were compared to the values obtained from 27 age-matched normal controls. The effect of testosterone treatment was determined by measuring changes in QBS and BMD, before and after treatment of 22 patients with DP and of all 16 patients with IHH. Seven patients with DP were not treated. RESULTS: In vivo QBS values in patients with DP were significantly higher than those in controls (8.44% +/- 2.55%ID/ml compared to 5.63% +/- 1.12%ID/ml x 10(-3), p < 0.001, for the LS; and 7.86% +/- 3.01%ID/ml compared to 4.29% +/- 1.25%ID/ml, p < 0.001, for the FN). One year after testosterone treatment, QBS values in DP were significantly reduced. Pretreatment BMD values in patients with DP were significantly lower than those in normal subjects (0.77 +/- 0.11 g/cm2 compared to 1.03 +/- 0.14 g/cm2, p < 0.0001, for the LS; and 0.89 +/- 0.11 g/cm2 compared to 1.08 +/- 0.18 g/cm2, p < 0.006, for the FN). One year after treatment, BMD values increased significantly (0.91 +/- 0.14 g/cm2, p < 0.0001, for the LS; and 0.97 +/- 0.11 g/cm2, p < 0.0001, for the FN). The seven untreated young men with DP still had significantly lower-than-normal BMD values (0.82 +/- 0.08 g/cm2, p < 0.008, for the LS; and 0.89 +/- 0.05 g/cm2, p < 0.04, for the FN). In patients with IHH, QBS values were not significantly different from those found in normal controls. The values for BMD were significantly lower for both the LS (p < 0.0001) and the FN (p < 0.001). After treatment, BMD values in patients with IHH were still significantly lower than those of normals (p < 0.009 for the LS; and p < 0.006 for the FN). CONCLUSION: Young men with maturation abnormalities show low bone density. Patients with DP and high bone turnover, as revealed by high QBS values, respond to testosterone treatment. Patients with IHH have normal bone turnover and do not respond to testosterone.

Quantitative bone scintigraphy using SPECT.

A quantitative single photon emission computed tomography (SPECT) technique for measuring radiopharmaceutical uptake in humans has been applied to bone scintigraphy. The method was validated by comparing SPECT measured percent of injected [99mTc]MDP in 16 normal skulls with well counter measurements of samples of the same bones obtained at surgery. A very good correlation (r = 0.96) was found. A very good interobserver correlation (r = 0.99) and agreement were also obtained when using quantitative bone scintigraphy (QBS). Control SPECT studies of uptake in the right and left iliac bones and the right and left sacroiliac regions in each patient showed no significant differences between the contralateral sides. Studies done in seven subjects at 2 and 4 hr after the same injection and in nine subjects 4 to 8 mo later in the same subjects showed a very good agreement and no significant differences between the two measurements were found. QBS is suggested as an accurate and reproducible index for assessment of the mass of remodeling bone. Preliminary results showed differences in QBS of normal subjects at different ages. A group of 68 young patients aged 18-26 yr showed a significant higher QBS (p less than 0.001) when compared to an older group of 62 patients aged 50-85 yr. There was, however, a wide range of uptake values for the same bone in the same group, suggesting that the method should best be used for following individual patients over time.

SPECT quantitation of iodine-131 concentration in phantoms and human tumors.

The validity of SPECT measurement of iodine-131 (131I) concentration was tested in vitro in phantoms and in vivo by measuring bladder urine concentrations. Phantom studies comparing known and SPECT measured concentrations showed a good correlation for 131I (r = 0.98, s.e.e. = 20.94 counts/voxel) for phantoms of 25 to 127 cc and concentrations of 0.13 to 9.5 microCi/cc. The in vivo, in vitro correlation of 131I concentrations in the urine was also good (r = 0.98, s.e.e. = 0.677 microCi/cc). Quantitative SPECT was used to calculate the effective half-life and dosimetry of radioiodine in 12 sites of thyroid carcinoma in seven patients. SPECT was also used to determine the dosimetry of [131I]MIBG (metaiodobenzylguanidine) in two patients with carcinoid, two with neuroblastoma, and one with pheochromocytoma. The radiation dose for thyroid carcinoma metastases varied between 6.3 and 276.9 rad/mCi. The dose from MIBG varied between 13.4 and 57.8 rad/mCi. These results indicate the validity of quantitative SPECT for in vivo measurement of 131I and the need to measure the concentration of 131I in individual human tumor sites.

Bone turnover in cortical and trabecular bone in normal women and in women with osteoporosis.

UNLABELLED: This study is based on the assumption that is bone turnover, shown by the uptake of 99mTc-MDP, indicates a high rate of bone loss in patients with osteoporosis, it could potentially predict bone loss in patients at risk before significant bone loss has occurred. METHODS: Quantitative bone SPECT (QBS) using 99mTc-MDP, expressed as the %ID/cc x 10(-3), was performed in 71 women who had osteoporosis in the lumbar vertebrae, the femoral neck or both, and in 54 age-matched normal female controls. Of the women with osteoporosis, 42 had postmenopausal osteoporosis and 29 had primary hyperparathyroidism (HPT) and osteoporosis. RESULTS: QBS increased with age in the cortical bone and decreased in the trabecular bone of the normal women. Quantitative bone SPECT in the femoral neck was 3.18 +/- 1.20 and was 2.73 +/- 1.06 in the femoral shaft in 20 women with postmenopausal osteoporosis of the femoral neck. In 19 women with HPT and osteoporosis of the femoral neck, the QBS value in the femoral neck was 3.57 +/- 0.92 and in the femoral shaft 3.38 +/- 1.12. These values were also significantly higher for the femoral neck and for the femoral shaft than those of normals. Although QBS values were higher in the lumbar region in 39 women with postmenopausal osteoporosis (4.59 +/- 1.45) and in 27 women with HPT (4.30 +/- 1.52), as compared with the normal group (4.28 +/- 1.61), the difference was not statistically significant. CONCLUSION: This study shows that bone turnover is significantly higher in the cortical bone of women with osteoporosis than in normal women.

Prediction of bone loss in patients with primary hyperparathyroidism using quantitative bone SPECT.

UNLABELLED: Bone loss is a major complication of primary hyperparathyroidism (PHPT), and it has significant implications in the treatment of this disease. Bone turnover was measured in patients with PHPT, using quantitative bone SPECT (QBS), to determine if the rate of bone loss could be predicted before a significant decrease in bone mass occurs. METHODS: Forty-six patients were included in the study. QBS and bone mineral density (BMD) of the lumbar spine (LS) and femoral neck (FN) were done at baseline. The percent deviation of QBS in patients with PHPT from the values in normal matched controls was calculated. BMD was measured again after a mean of 17.5 mo in 38 patients, and in 29 patients a repeat BMD study was done after a mean of 41.4 mo. The change in BMD in patients with high and normal QBS values was compared using the nonparametric Mann-Whitney test. Regression analysis tested the correlation between baseline QBS values and BMD changes over time. RESULTS: For the FN, there was a statistically significant difference in the BMD change between patients with high and normal QBS values for short-term follow-up (-2.82%+/-4.80% versus 1.45%+/-4.67%, p < 0.05) and for long-term follow-up (-3.53%+/-5.34% versus 0.92%+/-2.40, p < 0.02). There was a negative correlation in the FN, r=-0.48 between QBS values and the percentage of change in BMD. There was no significant difference between the percentage of change in BMD in the LS in patients with high and normal QBS values for either short- or long-term follow-up. CONCLUSION: The results of this study show that QBS can predict bone loss in the FN in patients with PHPT. QBS can thus indicate the need for surgery at an early stage of the disease to prevent bone loss.