99mTc-methylene Diphosphonate Scintigraphy Research Articles

Skeletal Changes in Hypoparathyroidism: X-ray to Bone Scintigraphy.

Parathyroid hormone (PTH) is a key in maintaining calcium homeostasis. Decreased PTH will result in decreased bone remodeling and increased bone density. The major cause is iatrogenic injury to parathyroid gland. X-ray and dual-energy X-ray absorptiometry are used to identify the skeletal changes. Typical skeletal changes are metaphyseal sclerosis in long bones and sclerosis of vertebrae and pelvic bones. 99mTc methylene diphosphonate scintigraphy is used to identify metabolic bone diseases. There are no typical scan findings in case of hypoparathyroidism. We like to report an interesting image of skeletal scintigraphy in case of hypoparathyroidism.

Coexistent Superscan and Lincoln Sign on Bone Scintigraphy

A 70-year-old man underwent Tc-methylene diphosphonate scintigraphy for staging of adenocarcinoma prostate. Scintigraphy revealed diffuse increased tracer uptake in skeletal system along with faint renal visualization, a pattern compatible with metastatic superscan. The scintigraphy also revealed increased radiotracer uptake in the body of the mandible-Lincoln sign or black beard sign. Radiological imaging revealed sclerotic lesions throughout the skeleton including the mandible, confirming widespread skeletal metastases. Lincoln sign is previously described in monostotic Paget disease of the mandible and in contiguous spread of oral malignancy. We describe this pattern in distant metastatic involvement from carcinoma prostate with coexistent superscan pattern.

Diagnostic value of 99mTc-ubiquicidin scintigraphy for osteomyelitis and comparisons with 99mTc-methylene diphosphonate scintigraphy and magnetic resonance imaging

The discrimination of bacterial infections from sterile inflammatory processes is of great importance in the management of inflammation. Currently available techniques cannot decisively address this issue. In this respect, antimicrobial peptide Tc-ubiquicidin (UBI) 29-41 scans have been showing interesting results. The aim of this study was to determine the accuracy of Tc-UBI scan in the detection of osteomyelitis and to compare it with Tc-methylene diphosphonate scan and magnetic resonance imaging (MRI). Twenty patients (mean age=48.90 years) with suspected osteomyelitis were included in this study. After evaluation of each patient through history taking, physical examination, appropriate laboratory tests, and other processes including bone probing, wound culture, and plain film radiography, MRIs, Tc-UBI scans, and Tc-methylene diphosphonate scans were performed. For quantitative analysis, the mean count of abnormal-to-normal (A/N) region was calculated for images acquired at 15, 30, 45, 60, 120, and 240 min to obtain the most favorable time for imaging. In total, osteomyelitis was detected in the Tc-UBI scans of 17 patients, indicating 100% accuracy, compared with an accuracy of 90% for osteomyelitis detected in three-phase bone scans. The maximum mean A/N was observed at 15 min after intravenous injection (median: 1.91; interquartile range: 1.54-2.94). MRI was performed in 12 cases only with 75% accuracy. In addition, the A/N ratios for the Tc-UBI scans were not significantly different between patients with or without Staphylococcus aureus growth on wound cultures. For fast imaging with high accuracy, Tc-UBI 29-41 is a suitable choice for the detection of osteomyelitis.

Prospective Evaluation of 99mTc MDP Scintigraphy, 18F NaF PET/CT, and 18F FDG PET/CT for Detection of Skeletal Metastases

Technetium (Tc) methylene diphosphonate (MDP) has been the standard method for bone scintigraphy for three decades. (18)F sodium fluoride ((18)F NaF) positron emission tomography (PET)/computed tomography (CT) has better resolution and is considered superior. The role of 2-deoxy-2-[(18)F]fluoro-D-glucose ((18)F FDG) PET/CT is proven in a variety of cancers, for which it has changed the practice of oncology. There are few prospective studies comparing these three methods of detection of skeletal metastases. Thus, we were prompted to initiate this prospective pilot trial. This is a prospective study (Sep 2007-Dec 2010) of 52 patients with proven malignancy referred for evaluation of skeletal metastases. There were 37 men and 15 women, 19-84 years old (average, 55.6 ± 15.9). Technetium-99m ((99m)Tc) MDP bone scintigraphy, (18)F NaF PET/CT, and (18)F FDG PET/CT were subsequently performed within 1 month. Skeletal lesions were detected by (99m)Tc MDP bone scintigraphy in 22 of 52 patients, by (18)F NaF PET/CT in 24 of 52 patients, and by (18)F FDG PET/CT in 16 of 52 patients. The image quality and evaluation of extent of disease were superior by (18)F NaF PET/CT over (99m)Tc MDP scintigraphy in all 22 patients with skeletal lesions on both scans and over (18)F FDG PET/CT in 11 of 16 patients with skeletal metastases on (18)F FDG PET/CT. In two patients, (18)F NaF PET/CT showed skeletal metastases not seen on either of the other two scans. Extraskeletal lesions were identified by (18)F FDG PET/CT in 28 of 52 subjects. Our prospective pilot-phase trial demonstrates superior image quality and evaluation of skeletal disease extent with (18)F NaF PET/CT over (99m)Tc MDP scintigraphy and (18)F FDG PET/CT. At the same time, (18)F FDG PET detects extraskeletal disease that can significantly change disease management. As such, a combination of (18)F FDG PET/CT and (18)F NaF PET/CT may be necessary for cancer detection. Additional evaluation with larger cohorts is required to confirm these preliminary findings.

Early Experience With Fluorine-18 Sodium Fluoride Bone PET in Young Patients With Back Pain

Skeletal positron emission tomography (PET) with fluorine-18 (18F) sodium fluoride (18F NaF) is an alternative to technetium-99m (99mTc)methylene diphosphonate (MDP) scintigraphy. Experience with pediatric PET is sparse, primarily in oncology. This study assesses the role of 18F NaF in evaluating young patients with back pain. Ninety-four 18F NaF PET scans were performed in 94 patients (27 males, 67 females; mean age, 15 years; range, 4-26 years) with back pain. Three-dimensional PET acquisition was performed 30 minutes after administration of 18F NaF (2.1 MBq/kg; maximum, 148 MBq). Radiation doses are presented for 18F NaF and 99mTc MDP. 18F NaF PET revealed a possible cause of back pain in 55% (52/94). Fifteen patients had 2 or more potential sources of back pain. Diagnoses by PET were pars interarticularis/pedicle stress (34%), spinous process injury (16%), vertebral body ring apophyseal injury (14%), stress at a transitional vertebra-sacral articulation (7%), and sacroiliac joint inflammation/stress (3%). Comparing 18F NaF PET with 99mTc MDP scintigraphy, time between injection and scanning was shorter (0.5 hours vs 3 hours), radiation dosimetry was similar (3.5 mGy vs 2.8 mGy effective dose for a 55-kg patient for 18F NaF and 99mTc MDP, respectively), and cost of radiopharmaceutical was higher. 18F NaF bone PET can detect a variety of skeletal abnormalities in young patients with back pain. Relative to 99mTc MDP, images are of higher resolution. Total time from tracer administration to completion is shorter, and radiation dosimetry is similar. Higher cost for 18F NaF may be offset by enhanced patient throughput.

Radiation-induced insufficiency fractures of the pelvis: evaluation with 99mTc-methylene diphosphonate scintigraphy.

99mTc-methylene diphosphonate (99mTc-MDP) bone scans in 80 patients, 30-80 years old (average, 62 years old) with uterine cancer who received high doses of radiation (10-60 Gy; average, 46 Gy) were reviewed retrospectively to evaluate the frequency of pelvic insufficiency fractures caused by radiotherapy and to study the appearance of the fractures on bone scans. Bone scans in 29 of 80 patients showed abnormalities in the pelvis: insufficiency fractures were identified in 27 patients (34%) and osseous metastases were found in two patients (3%). The fractures and metastases were diagnosed by CT and were confirmed by observing the patients' clinical courses. Fractures were identified in 27 (39%) of 69 postmenopausal women and in none of 11 premenopausal patients (p greater than .05). Fractures were found in 21 (84%) of 25 patients who had pelvic pain and in six (11%) of 55 patients who were asymptomatic (p greater than .001). Scintigrams in patients with fractures showed more than one fracture in most patients (85%), and fractures were often symmetric (67%). Scintigrams in two patients with osseous metastases showed increased activity in an iliac wing that was outside the radiation field. Our results suggest that a marked increase in insufficiency fractures occurs after radiation therapy, especially in postmenopausal patients. A symmetric area of increased uptake of radionuclide is a characteristic scintigraphic appearance of an insufficiency fracture.

Osteoarticular brucellosis: results of bone scintigraphy in 140 patients.

One hundred forty patients with proved brucellosis and clinical evidence of bone and joint involvement were evaluated prospectively by 99mTc-methylene diphosphonate scintigraphy to assess the frequency of positive findings. To evaluate the radiographic abnormalities associated with positive scintigraphy, all areas of the skeleton that showed abnormal uptake were studied further by plain radiography. High-resolution CT was performed in all patients who had spinal lesions. Ninety-six patients (69%) had abnormal radionuclide uptake in 57 extraspinal and 101 spinal sites. Uptake was increased in 53 joints and three long bones and decreased in one joint. The knee was the most frequently involved site; the second was the sacroiliac joint. Radiographic and high-resolution CT changes were seen in only 12 (21%) of 57 extraspinal sites. In the spine, the abnormal scintigrams showed either focal increased uptake in affected vertebral bodies (detected mostly on the anterior view and seen in 51 lower thoracic and lumbar vertebrae in 24 patients) or diffuse increased uptake in adjacent vertebrae (detected in anterior and posterior views and seen in 50 different disk levels in 38 patients). Radiographic and high-resolution CT changes were seen at all scintigraphically positive sites. We conclude that bone scintigraphy is a useful method for screening patients with osteoarticular brucellosis. It is more sensitive than radiography in assessing involvement of the extraspinal skeleton and in the spine, it allows accurate localization of affected areas.

Vertebral crush fracture syndrome and reflex sympathetic dystrophy

The association of reflex sympathetic dystrophy in one or more extremities with vertebral crush fracture syndrome is reported in six cases. In two of them the reflex sympathetic dystrophy preceded the vertebral crush fractures. The 99mTc-methylene diphosphonate scintigraphy results of the skeletons of 42 consecutive patients suffering from vertebral collapse and of 30 matched controls without osteoporosis have been evaluated by three independent observers for abnormal uptakes in the extremities. An abnormal radioactive bone tracer uptake in the extremities has been observed in 15 osteoporotics (36 %) and 8 controls (29 %). In most cases, osteoporotics and controls, the abnormal uptake was of the zonal type in a localized area, probably reflecting bone remodeling due to localized degenerative changes. An abnormal uptake of the segmental type involving multiple joints and even multiple extremities, as seen in reflex sympathetic dystrophy, was observed in 7 patients of the osteoporotic group (17%) and in none of the control group ( P < 0,05). The patients with an abnormal segmental uptake were younger and had a significantly higher mean 24 h calcium:creatinine ratio as well as a higher urinary hydroxyproline excretion. These observations and results suggest that in some cases of idiopathic osteoporosis there might be a relation between reflex sympathetic dystrophy and vertebral crush fracture syndrome, the vertebral crush fracture syndrome being the axial type of reflex xympathetic dystrophy.

A Technique to Evaluate Bone Healing in Non-Human Primates Using Sequential 99mTc-Methylene Diphosphonate Scintigraphy

The assessment of bone healing through sequential nuclear medical scintigraphy requires a method of consistent localization of the exact fracture area in each consecutive image as the study progresses. This is difficult when there is surrounding bone activity as in the early stages of trauma, and also if complications should set in. The image profile feature, available from most nuclear medical computer software, facilitates this procedure considerably, as is indicated in the present report on bone healing in baboons. Together with roentgenology and histology a 99mTc-MDP study was in this way successfully done on the healing of long bone fractures experimentally induced in non-human primates. Different surgical implants were used. The results indicate that 99mTc-MDP accurately reflects the physiological activity in bone. The time-activity curves obtained are presently being studied together with extensive histology, bearing possible clinical application in mind.