Multimodality Molecular Imaging in Arthropathy Associated with Multiple Myeloma

We report a patient with multiple myeloma (MM) and polyarthritis of large joints. During the staging of the disease, bone marrow diffusely involved by MM was clearly demonstrated by 99mTc-2-methoxy-isobutyl-isonitrile (MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) but not by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/CT images. On the other hand, a very intense uptake of 18F-FDG was detected in periarticular tissues of multiple joints, with nonabnormal 99mTc-MIBI accumulation. Rheumatology tests were negative. A subsequent bone scintigraphy demonstrated radiolabeled bisphosphonate accumulation in periarticular tissues, suggesting amyloid arthropathy.

Standardized Uptake Value from Semiquantitative Bone Single-Photon Emission Computed Tomography/Computed Tomography in Normal Thoracic and Lumbar Vertebrae of Breast Cancer Patients

STUDY DESIGN

Retrospective study.

PURPOSE

This study aims to semiquantitatively evaluate the standardized uptake value (SUV) of 99mTc-methylene diphosphonate (MDP) radionuclide tracer in the normal vertebrae of breast cancer patients using an integrated single-photon emission computed tomography (SPECT)/computed tomography (CT) scanner.

OVERVIEW OF LITERATURE

Molecular imaging techniques using gamma cameras and stand-alone SPECT have traditionally been utilized to evaluate metastatic bone diseases. However, these methods lack quantitative analysis capabilities, impeding accurate uptake characterization.

METHODS

A total of 30 randomly selected female breast cancer patients were enrolled in this study. The SUV mean (SUVmean) and SUV maximum (SUVmax) values for 286 normal vertebrae at the thoracic and lumbar levels were calculated based on the patients' body weight (BW), body surface area (BSA), and lean body mass (LBM). Additionally, 106 degenerative joint disease (DJD) lesions of the spine were also characterized, and both their BW SUVmean and SUVmax values were obtained. A receiver operating characteristic (ROC) curve analysis was then performed to determine the cutoff value of SUV for differentiating DJD from normal vertebrae.

RESULTS

The mean±standard deviations for the SUVmean and SUVmax in the normal vertebrae displayed a relatively wide variability: 3.92±0.27 and 6.51±0.72 for BW, 1.05±0.07 and 1.75±0.17 for BSA, and 2.70±0.19 and 4.50±0.44 for LBM, respectively. Generally, the SUVmean had a lower coefficient of variation than the SUVmax. For DJD, the mean±standard deviation for the BW SUVmean and SUVmax was 5.26±3.24 and 7.50±4.34, respectively. Based on the ROC curve, no optimal cutoff value was found to differentiate DJD from normal vertebrae.

CONCLUSIONS

In this study, the SUV of 99mTc-MDP was successfully determined using SPECT/CT. This research provides an approach that could potentially aid in the clinical quantification of radionuclide uptake in normal vertebrae for the management of breast cancer patients.

18F-Sodium Fluoride PET: History, Technical Feasibility, Mechanism of Action, Normal Biodistribution, and Diagnostic Performance in Bone Metastasis Detection Compared with Other Imaging Modalities

The skeleton is the third most common site for metastasis overall, after the lungs and liver. Accurate diagnosis of osseous metastasis is critical for initial staging, treatment planning, restaging, treatment monitoring, and survival prediction. Currently, ^99mTc-methylene diphosphonate whole-body scanning is the cornerstone of imaging to detect osseous metastasis. Although ¹⁸F-sodium fluoride (¹⁸F-NaF) was one of the oldest medical tracers for this purpose, it was replaced by other tracers because of their better physical properties, until recently. Continued development of PET scanners has opened a new era for ¹⁸F-NaF, and given its higher sensitivity, there have been increasing applications in imaging. In this review, we will discuss the history, technical aspects, radiobiology, and biodistribution of this tracer. Finally, we compare the accuracy of ¹⁸F-NaF PET with other conventional imaging methods for detection of osseous metastasis.

Serendipitous Detection of Extraosseous Metastases on Bone Scintigraphy: Utility of Cross-sectional and Correlative Imaging

Whole body bone scintigraphy is most commonly used imaging modality to detect and assess the extent of osteoblastic osseous metastases in malignant conditions, though visceral metastases need additional imaging. The authors describe a case of 50-year-old postoperative breast cancer female where bone scintigraphy showed soft tissue uptake in thorax and hepatic region in addition to multiple skeletal metastases, indicating the involvement of three different organs by metastatic disease. The present case highlights that extraosseous tracer uptake in addition to abnormal osseous tracer uptake may raise the suspicion of widespread and visceral metastatic disease and warrant further evaluation in the form of cross-sectional and correlative imaging.

[Progress of quantitative measurement of bone using 99mTc-methylene diphosphonate in osteoporosis]

As the incidence of osteoporosis (OP) is increasing year by year, high morbidity and mortality caused by osteoporotic fractures have become major problems of health in China and over the world. Quantitative measurement of bone using ^99mTc-methylene diphosphonate ( ^99mTc-MDP) provides global or local information of skeletal metabolism or transformation. In this paper, we make a brief review on the quantitative measurement of bone using ^99mTc-MDP and expect to provide guidance for clinical diagnosis and treatment.

Compression type stress fracture of femoral neck with equivocal X-ray features diagnosed on (99m)Tc-MDP SPECT/CT in a case of trivial hip pain

Stress insufficiency fracture is usually diagnosed clinically and on the basis of routine X-ray imaging findings. However, the absence of any known predisposing factors and negative or occult radiographic findings pose diagnostic challenges. We report the case of an elderly male patient who presented with a chief complaint of trivial left hip pain and with equivocal radiographic findings. Triphasic (99m)Tc-methylene diphosphonate bone scan and single-photon emission computed tomography/computed tomography helped in arriving at the diagnosis of stress insufficiency fracture involving femoral neck.

Role of (99m)Tc-methylene diphosphonate bone scan in the evaluation of the viability of the bone flap in mandibular reconstruction in patients with oromaxillofacial malignancies

Osteo-cutaneous flap are commonly used for reconstruction of bone defect after oncology surgery. The success of surgery depends on the viability of the bone flap. Bone scan is a known, but less performed method, to look for viability of bone flaps. We describe a case of 50-year-old lady, presenting with squamous cell carcinoma of left buccal mucosa (cT4N1M0) involving the skin and mandible. She underwent left segmental mandibulectomy and upper alveolectomy with neck dissection, followed by reconstruction using a fibular osteo-cutaneous flap and anterolateral thigh free flap. On postoperative day 10, the intraoral flap showed signs of nonviability. The patient was sent to nuclear medicine for assessment of viability of the free fibula flap. The patient underwent three phase ^99mTc-methylene diphosphonate (MDP) bone scan and single-photon emission computerized tomography. Computerized tomography showing good tracer uptake in fibula confirming viability. The case reflects the use of ^99mTc-MDP in viability assessment of the bone flap.

Metastatic superscan on (99m)Tc-methylene diphosphonate bone scintigraphy in pediatric neuroblastoma

Excessive skeletal radioisotope uptake in relation to soft tissues along with absent or faint activity in the genitourinary tract on bone scintigraphy (BS) is known as a "superscan." However the association of pediatric solid tumor malignancy with metastatic superscan has not been reported previously. We here describe two such cases of neuroblastoma who presented with metastatic superscan on (99m)Tc-methylene diphosphonate BS. Presence of a superscan usually indicates an advanced stage of the disease. The patient prognosis is usually poor. Though extremely rare superscan can be associated with pediatric solid tumor malignancies and should be kept in mind while reporting such cases.

Incremental value of single photon emission tomography/computed tomography in 3-phase bone scintigraphy of an accessory navicular bone

Accessory navicular bone is one of the supernumerary ossicles in the foot. Radiography is non diagnostic in symptomatic cases. Accessory navicular has been reported as a cause of foot pain and is usually associated with flat foot. Increased radio tracer uptake on bone scan is found to be more sensitive. We report a case highlighting the significance of single photon emission tomography/computed tomography in methylene diphosphonate bone scan in the evaluation of symptomatic accessory navicular bone where three phase bone scan is equivocal.

Asymmetrically increased rib cage uptake on bone scintigraphy: Incidental detection of pleural mesothelioma on single photon emission computed tomography/computed tomography

Follow-up bone scintigraphy (BS) in a patient of carcinoma left breast, who was treated with surgery followed by radiotherapy 12 years back, revealed asymmetrically increased radiotracer uptake in left-sided ribs. Since, this pattern was atypical for metastatic rib involvement, single photon emission computed tomography/computed tomography (SPECT/CT) of thorax was done in the same setting which revealed circumferential nodular left-sided pleural thickening. Biopsy confirmed it to be pleural mesothelioma. Left-sided ribs showed no abnormality on CT, thus suggesting the rib uptake as reactive in nature. This pattern of asymmetric rib uptake on BS should be kept in mind and warrants further investigation for determining underlying pathology.

Extraosseous accumulation of bone scan tracer (99m)Tc-methylene diphosphonate in a phlebolith

Uptake in non-osseous, non-urologic tissues is occasionally found in the performance of bone scintigraphy. These uptakes reflect an atypical interaction between the radiopharmaceutical and the patient. Knowledge of the rare extraskeletal uptakes and their clinical relevance helps in better interpretation of bone scans. We report an unusual occurrence of extraosseous accumulation of ^99mTc-methylene diphosphonate in a phlebolith in bone scan, confirmed with the aid of photon emission computed tomography and computed tomography.