Single-photon emission computed tomography combined with computed tomography (SPECT/CT) in bone diseases

Incidental Extracardiac Findings of Technetium-99m Pyrophosphate Scintigraphy: A Pictorial Review

Technetium-99m pyrophosphate (Tc-99m PYP) cardiac imaging is a simple, widely available, noninvasive method to identify patients with transthyretin-type cardiac amyloidosis (ATTR), and it has remarkably high diagnostic accuracy with very high sensitivity and specificity. Visual scores of 0, 1, 2, and 3 indicate non-myocardial uptake, uptake less than rib, equal to rib, and greater than rib uptake, respectively. Semiquantitative assessment using the heart-to-contralateral lung ratio of more than 1.5 at 1 hour accurately distinguishes ATTR from the cardiac amyloid light chain subtype. However, there are several incidental non-cardiac findings that can be seen in planar images, rotating single-photon emission computed tomography (SPECT) images, maximum intensity projection images, or computed tomography images acquired for attenuation correction. These findings may lead to the early detection of a noncardiac condition that may require additional treatment. The intent of this review is to demonstrate several incidental noncardiac abnormalities that have an impact on patient management and follow-up.

Spectral computed tomography-guided radiotherapy of osteosarcoma utilizing BiOI nanosheets

As an aggressive malignant bone tumor, osteosarcoma (OS) is usually found in children and adolescents. Computed tomography (CT) is an important tool for the clinical evaluation of osteosarcoma, but limits to low diagnostic specificity due to single parameters of traditional CT and modest signal-to-noise ratio of clinical iodinated contrast agents. As one kind of spectral CT, dual-energy CT (DECT), with the advantage of a provision of multi-parameter information, makes it possible to acquire the best signal-to-noise ratio image, accurate detection, as well as imaging-guided therapy of bone tumors. Hereby, we synthesized BiOI nanosheets (BiOI NSs) as a DECT contrast agent with superior imaging capability compared to iodine agents for clinical detection of OS. Meanwhile, the synthesized BiOI NSs with great biocompatibility is able to achieve effective radiotherapy (RT) by enhancing X-ray dose deposition at the tumor site, leading to DNA damage, which in turn inhibits tumor growth. This study offers a promising new avenue for DECT imaging-guided treatment of OS. STATEMENT OF SIGNIFICANCE: Osteosarcoma (OS) is a common primary malignant bone tumor. Traditional surgical procedures and conventional CT scans are often used for the treatment and monitoring of OS, but the effects are generally unsatisfactory. In this work, BiOI nanosheets (NSs) was reported for dual-energy CT (DECT) imaging-guided OS radiotherapy. The powerful and constant X-ray absorption of BiOI NSs at any energy guarantees excellent enhanced DECT imaging performance, allowing detailed visualization of OS through images with a better signal-to-noise ratio and guiding radiotherapy process. The deposition of X-rays could be greatly enhanced by Bi atoms to induce serious DNA damage in radiotherapy. Taken together, the BiOI NSs for DECT-guided radiotherapy will greatly improve the current treatment status of OS.

Bone Scan With SPECT/CT Demonstrated C1 to C2 Involvement in Rheumatic Arthritis

ABSTRACT

An 80-year-old man was treated with rituximab for active rheumatoid arthritis until 2019, now controlled with Salazopyrin, prednisolone, methotrexate, and folic acid. However, laboratory data showed elevated C-reactive protein and erythrocyte sedimentation rate. Whole-body bone scan showed bony and joint destruction to the upper cervical vertebra (C spine), bilateral shoulders, wrists, finger joints, ankles, and left knee. SPECT/CT localized the upper C spine uptake to the C1/C2 joint and adjacent C1 and C2 with C1/C2 subluxation. C spine CT showed vertical atlantoaxial subluxation and bony erosions.

Diagnostic Value of Bone SPECT/CT Using 99mTc-Methylene Diphosphonate in Patients with Unspecified Chest Wall Pain

PURPOSE

We investigated the diagnostic performance of single photon emission computed tomography (SPECT)/computed tomography (CT) as a combination of functional and anatomic imaging, in patients with unspecified chest wall pain.

METHODS

Fifty-two patients with unspecified chest wall pain and no history of recent major traumatic events or cardiac disease were included. The number and location of radioactive chest wall lesions were evaluated on both planar images and SPECT/CT. The clinical diagnosis was made based on all of the clinical and imaging data and follow-up information.

RESULTS

Chest wall diseases were diagnosed in 42 patients (80.8 %). SPECT/CT showed abnormal findings in 35 (67.3 %) patients with positive predictive value (PPV) of 97.1 %. SPECT/CT revealed 56 % more lesions than planar bone scan (P = 0.002) and most of the abnormal radioactive lesions (94.6 %) showed combined morphological changes on the matched CT component. When comparing between age subgroups (< 60 y vs. ≥ 60 y), the prevalence of chest wall disease and diagnosis rate of fracture was significantly higher in the older age group. On SPECT/CT, the older age group showed higher frequency of having abnormal finding (95.8 % vs. 42.9 %, P < 0.001) and significantly more lesions were detected (a total of 189 vs. 32, P = 0.003).

CONCLUSION

SPECT/CT showed good diagnostic performance and proved to have higher sensitivity, detecting 56 % more lesions than planar bone scan. A negative result could be helpful for excluding pathologic chest wall disease. SPECT/CT might be recommended for integration in to the diagnostic workup in patients with unspecified chest wall pain, especially in patients ≥ 60 y of age, considering the high disease prevalence and the high frequency of positive results.

Diagnostic Modality in Spine Disease: A Review

Spine diseases are common and exhibit several causes, including degeneration, trauma, congenital issues, and other specific factors. Most people experience a variety of symptoms of spine diseases during their lifetime that are occasionally managed with conservative or surgical treatments. Accurate diagnosis of the spine pathology is essential for the appropriate management of spine disease, and various imaging modalities can be used for the diagnosis, including radiography, computed tomography (CT), magnetic resonance imaging (MRI), and other studies such as EOS, bone scan, single photon emission CT/CT, and electrophysiologic test. Patient (or case)-specific selection of the diagnostic modality is crucial; thus, we should be aware of basic information and approaches of the diagnostic modalities. In this review, we discuss in detail, about diagnostic modalities (radiography, CT, MRI, electrophysiologic study, and others) that are widely used for spine disease.

Added value of hybrid SPECT with CT imaging for predicting poor therapeutic efficacy of 89Sr in patients with bone metastasis

To utilize single-photon emission computed tomography/computed tomography (SPECT/CT) scanning to investigate the usefulness of nerve root compression (NRC) and radioactive cold zone lesions (RCZLs) for predicting poor therapeutic efficacy of strontium-89 chloride (Sr-89) in patients with bone metastasis. Patients with bone metastatic neoplasms who had undergone baseline bone SPECT/CT scanning before Sr-89 therapy (148 MBq Sr-89 chloride by an intravenous injection for each patient) between July 2011 and July 2018 were included. Bone SPECT/CT images were assessed by two readers independently. Associations between imaging features and therapeutic efficacy were obtained via multivariate logistic regression analysis. Of 231 patients analyzed, 50 (21.6%) had NRC at baseline. Of 31 patients who experienced poor therapeutic efficacy, 29 (93.5%) had NRC. In multivariate logistic regression analysis baseline NRC independently predicted poor therapeutic efficacy. The sensitivity of NRC for predicting poor therapeutic efficacy was 93.5%, specificity was 89.5%, positive predictive value was 58.0%, and negative predictive value was 98.9%. RCZLs were detected in17 patients (7.4%), of whom 14 experienced poor Sr-89 therapeutic efficacy. The sensitivity of the presence of RCZLs for predicting poor therapeutic efficacy was 45.2%, specificity was 98.5%, positive predictive value was 82.4%, and negative predictive value was 92.1%. After adjusting for age, bone metabolism and lesion type, the significant independent predictors of poor Sr-89 therapeutic efficacy were presence of NRC (p < 0.001) and RCZL (p = 0.001). NRC and RCZL on baseline bone SPECT/CT are reliable independent predictors of poor Sr-89 therapeutic efficacy in patients with bone metastasis. These associations may facilitate the administration of more effective therapeutic interventions.

Reactive Oxygen Species, Metabolic Plasticity, and Drug Resistance in Cancer

The metabolic abnormality observed in tumors is characterized by the dependence of cancer cells on glycolysis for their energy requirements. Cancer cells also exhibit a high level of reactive oxygen species (ROS), largely due to the alteration of cellular bioenergetics. A highly coordinated interplay between tumor energetics and ROS generates a powerful phenotype that provides the tumor cells with proliferative, antiapoptotic, and overall aggressive characteristics. In this review article, we summarize the literature on how ROS impacts energy metabolism by regulating key metabolic enzymes and how metabolic pathways e.g., glycolysis, PPP, and the TCA cycle reciprocally affect the generation and maintenance of ROS homeostasis. Lastly, we discuss how metabolic adaptation in cancer influences the tumor’s response to chemotherapeutic drugs. Though attempts of targeting tumor energetics have shown promising preclinical outcomes, the clinical benefits are yet to be fully achieved. A better understanding of the interaction between metabolic abnormalities and involvement of ROS under the chemo-induced stress will help develop new strategies and personalized approaches to improve the therapeutic efficiency in cancer patients.

Use of Single-Photon Emission Computed Tomography Imaging for Hypermetabolic Facet Identification in Diagnosis of Cervical and Axial Back Pain

BACKGROUND

Few studies have used hybrid single-photon emission computed tomography (SPECT)/computed tomography (CT) scan to identify degenerative facet disease. We aimed to determine the incidence of hypermetabolic facets on SPECT/CT imaging in patients with axial neck or back pain to elucidate the value of SPECT/CT scan in identifying pain generators.

METHODS

A retrospective review of adult patients with axial neck or back pain was conducted. A total of 190 patients underwent high-resolution SPECT/CT imaging using a standardized protocol from January 2010 to April 2018. Facet joints with increased radionuclide uptake on SPECT imaging were characterized as hypermetabolic. Number, level, and laterality of hypermetabolic facets were recorded based on review of imaging and radiologist impressions.

RESULTS

The average age of the patients was 58 ± 13 years, and 51% of patients were men. A total of 85 patients (48%) demonstrated zygapophyseal joint hypermetabolism (ZJH) on SPECT imaging. A total of 202 hypermetabolic facets were identified, indicating the average number of facets with ZJH was 2.38 ± 1.91. Of patients with a positive scan, lumbar facets were most commonly affected (69% of ZJH) followed by cervical (24%) and thoracic regions (6%). C1-2 and C2-3 (22% each of cervical ZJH) and L4-5 (32% of lumbar ZJH) were most commonly affected in the cervical and lumbar regions, respectively.

CONCLUSIONS

Nearly half of all patients with axial neck or back pain demonstrated ZJH on SPECT/CT imaging, supporting ZJH sites as potential pain generators and targets for treatment. Our results support the role for SPECT/CT imaging in the workup of patients with axial neck or back pain, which may reduce invasive diagnostic procedures and aid in treatment planning.

Bone SPECT/CT of the Foot and Ankle: Potential Clinical Application for Chronic Foot Pain

Diseases of the foot and ankle are common but relatively difficult to diagnose because of the complexity of the anatomy and the frequent occurrence of multiple diseases at the same time. For these reasons, management of chronic foot pain is often clinically challenging. MRI is the imaging modality of choice in many types of diseases causing chronic foot pain, due to high resolution and excellent soft tissue contrast. However, in the postoperative state, the use of MRI can be limited by artifact from metallic devices, and it may be difficult to confirm whether the pathology detected on the MRI is the actual cause of the pain. As bone scintigraphy provides metabolic information, it can help to find the origin of pain, and SPECT/CT can further improve the specificity by adding anatomical information. In daily clinical practice for management of foot and ankle pathologies, the use of bone SPECT/CT is gradually increasing. However, there has been limited evidence of usefulness of SPECT/CT in evaluating chronic foot pain. In this review article, the potential application of bone SPECT/CT for chronic foot pain is illustrated, and the role of SPECT/CT in the management of the foot and ankle diseases in clinical practice is described.

Utility of bone SPECT/CT to identify the primary cause of pain in elderly patients with degenerative lumbar spine disease

Background

Diagnosis of the cause of low back pain in the presence of degenerative spine disease using conventional imaging techniques, especially in elderly individuals, is challenging. Our aim was to describe our use of bone scintigraphy with single photon emission computed tomography (bone SPECT/CT) in the assessment of low back pain in elderly patients with degenerative lumbar spine disease, underlining the clinical utility of bone SPECT/CT imaging in this clinical population to inform diagnosis and treatment.

Methods

Between January 2016 and December 2017, we used bone SPECT/CT to successfully identify the cause of low back pain in five elderly patients. All patients had been scheduled for extensive spinal fusion surgery based on conventional imaging (plain radiography, computed tomography, and magnetic resonance).

Results

After diagnosis using bone SPECT/CT, three patients underwent spinal fusion at 1–2 levels with specific degenerative disk and joint disease, with the other two patients successfully treated using a conservative approach for a non-traumatic insufficiency fracture of the endplate of the L4 vertebral body and a fracture of the transverse process of L3. Clinically meaningful decrease in pain and fracture healing were obtained with conservative treatment.

Conclusion

Bone SPECT/CT was useful to identify the specific cause of pain in elderly patients with lumbar degenerative disease and to provide appropriate treatment, avoiding the unnecessary use of invasive spinal fusion surgery. Therefore, the clinical utility of bone SPECT/CT is potentially high as it improves diagnosis and lowers the risk of inappropriate invasive spinal surgery.

Primary Aspergillosis of the Sphenoid Sinus Observed on Bone SPECT/CT

The bone SPECT/CT allows for precise anatomic delineation of bone activity, which can be valuable for diagnosis of nonmalignant bone diseases. We report an extremely rare case of sphenoid sinus aspergillosis, observed on bone SPECT/CT imaging, as an isolated disease in an immunocompetent individual. A 58-year-old woman with a history of plantar fasciitis was assessed for infection in the tarsal bones. Planar bone scan image revealed incidental focal lesion in skull base, which was considered to be the left sphenoid sinusitis by the bone SPECT/CT scan.

Skeletal abnormalities detected by SPECT is associated with increased relapse risk in pediatric acute lymphoblastic leukemia

Objectives

Most children with acute lymphoblastic leukemia (ALL) exhibit skeletal abnormalities. This study aimed to investigate bone lesions detected by whole-body bone single-photon emission computed tomography (SPECT) and its prognostic value in children with ALL.

Methods

A retrospective analysis was performed using whole-body bone SPECT scans obtained from children with ALL in our department between June 2008 and June 2012. A total of 166 children newly diagnosed with ALL were included, and the patients were divided into two groups: patients with positive and negative SPECT scans. We compared the clinical characteristics of the two groups and analyzed the relationship between the skeletal abnormalities detected by SPECT and prognosis.

Results

Among the 166 patients, bone scintigraphic abnormalities was detected by SPECT scan in sixty-four patients (38.6%). The most common site was the limbs. There were no significant differences in age, gender, WBC count at diagnosis, risk group and minimal residual disease (MRD) level between SPECT-positive patients and their SPECT-negative counterparts. The event-free and overall survival rates were higher in SPECT-positive patients, but the difference was not statistically significant. However, patients with positive SPECT scans, especially those with multifocal abnormalities (≥3 sites), had a higher rate of relapse (P < 0.05). Multivariate analyses identified that abnormal SPECT scan (HR = 3.547, P = 0.015) was an independent relapse risk.

Conclusion

Children with ALL and multiple skeletal abnormalities will suffer from relapse. Abnormal SPECT scan was associated with increased relapse risk which might be a potential relapse marker for ALL children.

Hybrid Bone SPECT/CT Imaging in Evaluation of Chronic Low Back Pain: Correlation with Facet Joint Arthropathy

BACKGROUND

Evidence to support the use of bone hydroxydiphosphonate (HDP) single photon emission computed tomography (SPECT/CT) in patients with facetogenic low back pain (LBP) is still limited. In this study we compared the scintigraphic patterns on bone SPECT/CT with the degree of structural facet joint (FJ) degeneration on CT in patients with LBP.

METHODS

Ninety-nine consecutive patients with LBP were prospectively evaluated. Patients with known or suspected malignancy, trauma, infectious processes, chronic inflammatory diseases, and previous surgery were excluded. The effect of LBP on the daily quality of life was assessed with the Oswestry disability index (ODI). The Pathria grading system was used to score FJ degeneration on CT scans. The correlation between the degree of FJ degeneration and osteoblastic activity on SPECT/CT was analyzed with Kappa statistics.

RESULTS

Ninety-nine patients were included (59 female, mean age 56.2 years). The mean ODI score was 38.5% (range, 8% to 72%). In all, 792 FJ (L2-3 to L5-S1) were examined. Of the FJs, 49.6% were Pathria grade 0-1 (normal to mild degeneration) on CT, 35% were grade 2 (moderate degeneration), and 16% were grade 3 (severe degeneration). Sixty-seven percent of the patients had scintigraphically active FJs on SPECT/CT. Sixty-nine percent of Pathria grade 3 FJs were scintigraphically active; 5.5% and 16.8% of Pathria grade 0-1 and Pathria grade 2, respectively, were active. Of the metabolically active FJs, 71.4% were at the L4-5/L5-S1 levels.

CONCLUSIONS

The ability of SPECT/CT to precisely localize scintigraphically active FJs may provide significant improvement in the diagnosis and treatment of patients with LBP. In this study we demonstrate that in >40% of FJs, the scintigraphic patterns on SPECT/CT did not correlate with the degree of degeneration on CT.

The emerging role and targetability of the TCA cycle in cancer metabolism

The tricarboxylic acid (TCA) cycle is a central route for oxidative phosphorylation in cells, and fulfills their bioenergetic, biosynthetic, and redox balance requirements. Despite early dogma that cancer cells bypass the TCA cycle and primarily utilize aerobic glycolysis, emerging evidence demonstrates that certain cancer cells, especially those with deregulated oncogene and tumor suppressor expression, rely heavily on the TCA cycle for energy production and macromolecule synthesis. As the field progresses, the importance of aberrant TCA cycle function in tumorigenesis and the potentials of applying small molecule inhibitors to perturb the enhanced cycle function for cancer treatment start to evolve. In this review, we summarize current knowledge about the fuels feeding the cycle, effects of oncogenes and tumor suppressors on fuel and cycle usage, common genetic alterations and deregulation of cycle enzymes, and potential therapeutic opportunities for targeting the TCA cycle in cancer cells. With the application of advanced technology and in vivo model organism studies, it is our hope that studies of this previously overlooked biochemical hub will provide fresh insights into cancer metabolism and tumorigenesis, subsequently revealing vulnerabilities for therapeutic interventions in various cancer types.

Hybrid Bone Single Photon Emission Computed Tomography Imaging in Evaluation of Chronic Low Back Pain: Correlation with Modic Changes and Degenerative Disc Disease

BACKGROUND AND OBJECTIVE

Multiple radiologic modalities are used in the evaluation of patients with low back pain (LBP). Only limited evidence currently exists to support the use of bone hydroxydiphosphonate single photon emission computed tomography (SPECT/CT) in patients with Modic changes (MCs) and degenerative disc disease. The aim of this study was to assess the value of the hybrid bone SPECT/CT imaging in patients with chronic LBP. We evaluate the correlation of hybrid bone SPECT/CT imaging patterns with MCs and disc abnormalities on magnetic resonance imaging (MRI).

METHODS

This was a prospective study. Ninety-nine consecutive patients with LBP from a single center. The degree of lumbar intervertebral disc and endplate degeneration on MRI and osteoblastic activity was shown on SPECT/CT. These 99 consecutive patients with LBP were prospectively evaluated. Patients with contemporary lumbosacral spine MRI and bone SPECT/CT were included. Patients with known or suspected malignancy, trauma, infectious processes, and previous surgery were excluded. The effect of LBP on the daily quality of life was assessed using Oswestry disability index. We analyzed the correlation between the degenerative changes at the intervertebral disc spaces and endplates on MRI and bone SPECT/CT findings using receiver operating characteristic curve analysis and Kappa statistics. The Pfirrmann grading system was used to score the severity of disc space degeneration on MRI scans.

RESULTS

A total of 99 patients were included in the study (58 women, 41 men; mean age, 56.2 years). Mean Oswestry disability index score was 38.5% (range, 8%-72%). The L2-3 through to L5-S1 levels were studied. MCs were found in 54% of patients. Of the 396 levels examined 85 were found to have MCs (21.5%). The most affected levels were L4-5 (31.3%) and L5-S1 (40.9%). Pfirrmann grade 5 disc space (72.9%) was associated with MC (Pp<0.001). MC (70.6%) and Pfirrmann grade 5 disc spaces (73%) resulted in scintigraphically active endplate/disc space on SPECT/CT (P< 0.001). Bone SPECT/CT showed high metabolic activity in 96.1% of endplates with MC type I, 56% with MC type II, and 77.8% with MC type III.

CONCLUSIONS

In this study we found a high agreement between MCs and increased metabolic activity on bone SPECT/CT imaging. MC type 1 and Pfirrmann grade 5 were the best binary predictors for positivity on bone SPECT/CT and had equivalent correlations. Lower vertebral levels in the lumbar spine were associated with higher degree of disc degeneration, high frequency of MCs, and positivity on bone SPECT/CT.

Primary pain generator identification by CT-SPECT in a patient with low back pain: a case report

Background

Chronic low back pain is one of the most common conditions encountered in the middle-age population. Identifying the primary pain generator is notoriously difficult. The computed tomography–single-photon emission computed tomography (CT–SPECT) is emerging as a new diagnostic modality for this purpose.

Case presentation

This 68-year-old Caucasian male presented with intractable low back pain refractory to maximal conservative treatment, including medication and extensive physical therapy. The lumbar computed tomography, magnetic resonance imaging, and flexion–extension X-rays showed advanced degenerative changes throughout the lumbar spine, but no single level significantly worse than the others. The CT–SPECT showed markedly increased uptake at the L1–2 disc level and only minimal uptake at the other levels. The patient underwent a minimally invasive lateral L1–2 fusion with near-complete resolution of his low back pain.

Conclusions

The CT–SPECT may provide a unique tool in establishing the primary pain generator in patients with degenerative spine disease.

Correlation of Uptake Patterns on Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) and Treatment Response in Patients with Knee Pain

PURPOSE

To determine whether treatment response in patients with knee pain could be predicted using uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT) images.

METHODS

Ninety-five patients with knee pain who had undergone SPECT/CT were included in this retrospective study. Subjects were divided into three groups: increased focal uptake (FTU), increased irregular tracer uptake (ITU), and no tracer uptake (NTU). A numeric rating scale (NRS-11) assessed pain intensity. We analyzed the association between uptake patterns and treatment response using Pearson's chi-square test and Fisher's exact test. Uptake was quantified from SPECT/CT with region of interest (ROI) counting, and an intraclass correlation coefficient (ICC) calculated agreement. We used Student's t-test to calculate statistically significant differences of counts between groups and the Pearson correlation to measure the relationship between counts and initial NRS-1k1. Multivariate logistic regression analysis determined which variables were significantly associated with uptake.

RESULTS

The FTU group included 32 patients; ITU, 39; and NTU, 24. With conservative management, 64 % of patients with increased tracer uptake (TU, both focal and irregular) and 36 % with NTU showed positive response. Conservative treatment response of FTU was better than NTU, but did not differ from that of ITU. Conservative treatment response of TU was significantly different from that of NTU (OR 3.1; p = 0.036). Moderate positive correlation was observed between ITU and initial NRS-11. Age and initial NRS-11 significantly predicted uptake.

CONCLUSIONS

Patients with uptake in their knee(s) on SPECT/CT showed positive treatment response under conservative treatment.

Bone Scintigraphy in the Diagnosis of Rheumatoid Arthritis: Is There Additional Value of Bone Scintigraphy with Blood Pool Phase over Conventional Bone Scintigraphy?

We aimed to investigate the value of bone scintigraphy with additional blood pool phase (BSBP), compared with conventional bone scintigraphy (CBS), in the assessment of rheumatoid arthritis (RA). A total of 242 patients (43 males, 199 females; 14-78 years) with arthralgia, and underwent BSBP were retrospectively analyzed. On the first physical examination, active arthritis was found in 128 of the 242 patients. Clinical diagnosis was made by a rheumatologist on the basis of the 1987 American College of Rheumatology (ACR) criteria, which are considered to be the gold standard. The diagnostic performances and prognostic value of BSBP and CBS were analyzed in the total patients with arthralgia and in the patients with arthritis. The sensitivity of BSBP (84.2%, 80/95) were significantly higher than that of CBS (74.8%, 72/95) in the patients with arthralgia (P = 0.039). When BSBP was interpreted with the results of elevated/positive anti-CCP antibody, its accuracy over CBS also became significantly higher (86.0%, 208/242 vs. 83.1%, 201/242 respectively, P = 0.021). The diagnostic odds ratio of BSBP positivity was higher than CBS positivity in the patients with arthralgia (26.0, 12.9-52.4 vs. 21.1, 10.8-41.3) and with arthritis (12.0, 4.9-29.4 vs. 10.0, 4.2-23.4). Both BSBP and CBS appear to provide acceptable accuracy and comparable diagnostic performance for diagnosis of RA. However, in the patients with arthralgia, BSBP was found to be more sensitive than CBS and more accurate when interpreted with the result of anti-CCP antibody. This could help physicians diagnose RA in daily clinical practice.

Diagnostic value of single-photon emission computed tomography combined with computed tomography in relation to MRI on osteochondral lesions of the talus

BACKGROUND

Osteochondral lesion of the talus (OLT) involves the separation of a fragment of articular cartilage, as defined by Kappis in 1922. MRI is the current standard for noninvasive diagnosis of OLT. Single-photon emission computed tomography combined with computed tomography (SPECT/CT) provides both morphologic and functional information. The purpose of the study was to compare SPECT/CT with MRI for image interpretation and treatment decision making in talar osteochondral lesions.

MATERIALS AND METHODS

A total of 21 patients (four bilateral) were evaluated with MRI and SPECT/CT. Diagnostic arthroscopy was performed to validate the indication by identifying unstable cartilage areas. Activation was assessed in nine regions of interest, as described by Elias and colleagues. SPECT/CT findings were assessed by the modified scoring system of Hart and colleagues, and MRI findings with the modified classification system of Hepple and colleagues. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated for SPECT/CT and MRI.

RESULTS

A total of 25 lesions were identified. Seventeen lesions were located on the medial third of the talar dome, eight on the lateral third, and seven on the central third. Four patients revealed diffuse uptake on more than one zone on SPECT/CT. SPECT/CT identified two subchondral lesions, which were not visualized on MRI.

CONCLUSION

MRI is the current standard for OLT diagnosis. SPECT/CT allows a three-dimensional localization of scintigraphic osteoblastic activity in the area of interest, providing additional information about the involvement of the subchondral bone and the vitality of the osteochondral lesion and the location of multiple lesions. We recommend the use of SPECT/CT and MRI together for comprehensive diagnostic assessment of OLT.

ACR Appropriateness Criteria Follow-Up of Malignant or Aggressive Musculoskeletal Tumors

Appropriate imaging modalities for the follow-up of malignant or aggressive musculoskeletal tumors include radiography, MRI, CT, (18)F-2-fluoro-2-deoxy-D-glucose PET/CT, (99m)Tc bone scan, and ultrasound. Clinical scenarios reviewed include evaluation for metastatic disease to the lung in low- and high-risk patients, for osseous metastatic disease in asymptomatic and symptomatic patients, for local recurrence of osseous tumors with and without significant hardware present, and for local recurrence of soft tissue tumors. The timing for follow-up of pulmonary metastasis surveillance is also reviewed. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Acute Osteochondral Fractures in the Lower Extremities - Approach to Identification and Treatment

Chondral and osteochondral fractures of the lower extremities are important injuries because they can cause pain and dysfunction and often lead to osteoarthritis. These injuries can be misdiagnosed initially which may impact on the healing potential and result in poor long-term outcome. This comprehensive review focuses on current pitfalls in diagnosing acute osteochondral lesions, potential investigative techniques to minimize diagnostic errors as well as surgical treatment options. Acute osteochondral fractures are frequently missed and can be identified more accurately with specific imaging techniques. A number of different methods can be used to fix these fractures but attention to early diagnosis is required to limit progression to osteoarthritis. These fractures are common with joint injuries and early diagnosis and treatment should lead to improved long term outcomes.

Extraosseous Findings on Bone Scintigraphy Using Fusion SPECT/CT and Correlative Imaging

OBJECTIVE

Extraosseous radioactivity outside of the expected biodistribution is often encountered on (99m)Tc-methylene diphosphate (MDP) bone scintigraphy, and proper interpretation requires an understanding of the mechanisms underlying this uptake and knowledge of the possible causes, depending on the site or structure involved.

CONCLUSION

We present examples of extraosseous radiotracer uptake seen on (99m)Tc-MDP bone scans in which either SPECT with integrated CT or correlative imaging improved the study's interpretation.

Image registration accuracy of an in-house developed patient transport system for PET/CT+MR and SPECT+CT imaging

OBJECTIVE

The aim of this study was to investigate the registration accuracy of a newly developed patient shuttle system that can integrate different scanners by patient transfer without repositioning for 'hardware'-based image fusion. We aimed to assess the registration accuracy of image fusion in two different settings: a trimodality PET/CT+MR system and a SPECT+CT system.

MATERIALS AND METHODS

In this prospective study, 43 patients underwent either sequential PET/CT and MR (n=31) or sequential SPECT and diagnostic CT (D-CT) (n=12). A side-loading patient shuttle system was used for patient transport. For PET/CT+MR, hardware-only coregistration was performed and then validated with anatomical landmarks on CT and MR. SPECT+D-CT image fusion was performed with external cobalt-57 markers and manual fusion. Registration accuracy was analysed by anatomical landmarks on the attenuation correction CT and the D-CT.

RESULTS

For the PET/CT+MR system, the mean offset between original CT and MR images in all 31 patients was 8.1±5.7 mm in the X-axis, 5±4 mm in the Y-axis and 4.9±5.6 mm in the Z-axis. The validation of the cobalt-57 marker-assisted SPECT+D-CT fusion yielded offsets of 0.7±1.7 mm in the X-axis, 2.1±1.7 mm in the Y-axis and 0.8±1.8 mm in the Z-axis.

CONCLUSION

Sequential PET/CT+MR and SPECT+D-CT imaging using a dedicated patient shuttle system is feasible, resulting in mean offsets between data sets of 10.7 mm using the gantry laser system and 2.4 mm with fiducial markers.

Comparison of SPECT/CT and MRI in diagnosing symptomatic lesions in ankle and foot pain patients: diagnostic performance and relation to lesion type

Purpose

The purpose of this study was to compare the diagnostic performance of SPECT/CT and MRI in patients with ankle and foot pain, with regard to the lesion types.

Materials and Methods

Fifty consecutive patients with ankle and foot pain, who underwent ^99mTc-MDP SPECT/CT and MRI, were retrospectively enrolled in this study. Symptomatic lesions were determined based on clinical examination and response to treatment. On MRI and SPECT/CT, detected lesions were classified as bone, ligament/tendon, and joint lesions. Uptake on SPECT/CT was assessed using a 4-grade system. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of SPECT/CT and MRI were evaluated in all detected lesions and each lesion type. Diagnostic value of uptake grade was analyzed using receiver-operating characteristics (ROC) curve analysis, and diagnostic performance was compared using Chi-square or McNemar tests.

Results

In overall lesions, the sensitivity, PPV and NPV of SPECT/CT for symptomatic lesions were 93%, 56%, 91%, and they were 98%, 48%, 95% for MRI. There was no significant difference between SPECT/CT and MRI. However, the specificity of SPECT/CT was significantly higher than that of MRI (48% versus 24%, P = 0.016). Uptake grade on SPECT/CT was significantly higher in symptomatic lesions (P < 0.001), and its area under curve on ROC analysis was 0.787. In the analysis of each lesion type, the specificity of SPECT/CT was poor in joint lesions compared with other lesion types and MRI (P < 0.001, respectively). MRI exhibited lower specificity than SPECT/CT in bone lesions (P = 0.004) and ligament/tendon lesions (P < 0.001).

Conclusions

SPECT/CT has MRI-comparable diagnostic performance for symptomatic lesions in ankle and foot pain patients. SPECT/CT and MRI exhibit different diagnostic specificity in different lesion types. SPECT/CT may be used as a complementary imaging method to MRI for enhancing diagnostic specificity.

The role of bone scintigraphy in the diagnosis of rheumatoid arthritis according to the 2010 ACR/EULAR classification criteria

We aimed to investigate the role of bone scintigraphy (BS) in the diagnosis of rheumatoid arthritis (RA) as a supplement to the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria. A total of 156 patients who underwent BS with screening laboratory to confirm RA were enrolled. We divided them into two groups according to the presence of arthritis upon the first physical examination, and evaluated the diagnostic validity of BS as an independent (BS only) or assistant diagnostic tool using the 2010 criteria (BS-assisted). Seventy-five patients had active arthritis (Group I), while the remaining 81 patients did not (Group II). Among them, 56 patients in group I and 5 patients in group II were finally classified as RA. In the group I patients who were eligible for application of the 2010 criteria, the sensitivity of the BS only and BS-assisted diagnosis was not superior to that of the 2010 criteria. However, BS-assisted diagnosis showed high positive prediction values in group I patients with 2010 criteria score < 6 and group II patients. Therefore, BS is still helpful to detect RA even after the introduction of the 2010 criteria, especially among patients who do not satisfy the 2010 criteria as well as those who are ineligible for the 2010 criteria due to dubitable arthritis at clinical presentation.

Is hybrid imaging (SPECT/CT) a useful adjunct in the management of suspected facet joints arthropathy?

PURPOSE

The purpose of this study was to assess the value of SPECT/CT imaging in patients with chronic spinal pain.

METHODS

This was a retrospective consecutive study. Patients with chronic neck or back pain from outpatient spinal clinics with clinical features raising the possibility of a facetogenic pain generator and non-conclusive MRI/CT findings were included. Imaging was performed on a dual-headed, hybrid SPECT/CT γ-camera with a low-dose CT transmission scan acquired after the SPECT study. SPECT/CT studies were viewed in the coronal, axial, and sagittal planes and in 3-dimensional mode. Descriptive statistical analysis was performed.

RESULTS

Seventy-two patients were included (37 females, 35 males, mean age of 53.9 years). There were 25 cervical spine scans and 49 lumbar spine scans. In the cervical spine group, 13 (52 %) patients had scintigraphically active cervical facet joint arthropathy and ten (36 %) had other pathology identified. Two thirds of patients diagnosed with facet joint arthropathy received steroid guided injections following their scans. In the lumbar spine group 34 (69.4 %) patients had scintigraphically active lumbar facet joint arthropathy and eight had other pathology identified. Twenty patients (58.8 %) diagnosed with facet joint arthropathy subsequently received steroid guided injections.

CONCLUSIONS

Hybrid SPECT/CT imaging identified potential pain generators in 92 % of cervical spine scans and 86 % of lumbar spine scans. The scan precisely localised SPECT positive facet joint targets in 65 % of the referral population and a clinical decision to inject was made in 60 % of these cases.

Combined single photon emission computerized tomography and conventional computerized tomography: Clinical value for the shoulder surgeons?

With the cases described, we strive to introduce single photon emission computerized tomography in combination with conventional computer tomography (SPECT/CT) to shoulder surgeons, illustrate the possible clinical value it may offer as new diagnostic radiologic modality, and discuss its limitations. SPECT/CT may facilitate the establishment of diagnosis, process of decision making, and further treatment for complex shoulder pathologies. Some of these advantages were highlighted in cases that are frequently seen in most shoulder clinics.

SPECT-CT with 67Ga-citrate in the management of spondylodiscitis

Spondylodiscitis affects a small proportion of all patients with locomotor system infections, however its early diagnosis is important due to its potential morbidity. Magnetic resonance imaging is the diagnostic method of choice. Nonetheless, it has certain limitations and is not suitable for all patients. The conventional scintigraphic studies for evaluating spondylodiscitis are those performed with (99m)Tc-HDP and (67)Ga-citrate. However, their poor image resolution is a disadvantage of these techniques. The use of hybrid Single Photon Emission Computed Tomography-Computed Tomography (SPECT-CT) improves detection of the disease by combining functional and anatomical images. We present 9 patients with suspicion of spondylodiscitis who underwent sequential bone scintigraphy with (99m)Tc-HDP and SPECT-CT with (67)Ga-citrate, with positive findings confirmed by clinical monitoring for at least 6 months.

A case of paranasal sinuses osteoma detected on bone SPECT/CT

We present a 51-year-old woman with a history of colectomy for colon cancer who was referred to our department for bone assessment. Planar image revealed a focus of increased uptake of Tc-99m methylene diphosphonate in the nose root. According to the images of SPECT combined with low-dose CT, the abnormal radiotracer uptake at the site of left frontal sinus was considered to be osteoma. We conclude that SPECT/CT provides an accurate evaluation of the localization of the lesions and supplies anatomic information that can be valuable for diagnosis of nonmalignant bone diseases.

SPECT/CT imaging of the lumbar spine in chronic low back pain: a case report

Mechanical low back pain is a common indication for Nuclear Medicine imaging. Whole-body bone scan is a very sensitive but poorly specific study for the detection of metabolic bone abnormalities. The accurate localisation of metabolically active bone disease is often difficult in 2D imaging but single photon emission computed tomography/computed tomography (SPECT/CT) allows accurate diagnosis and anatomic localisation of osteoblastic and osteolytic lesions in 3D imaging. We present a clinical case of a patient referred for evaluation of chronic lower back pain with no history of trauma, spinal surgery, or cancer. Planar whole-body scan showed heterogeneous tracer uptake in the lumbar spine with intense localisation to the right lateral aspect of L3. Integrated SPECT/CT of the lumbar spine detected active bone metabolism in the right L3/L4 facet joint in the presence of minimal signs of degenerative osteoarthrosis on CT images, while a segment demonstrating more gross degenerative changes was more quiescent with only mild tracer uptake. The usefulness of integrated SPECT/CT for anatomical and functional assessment of back pain opens promising opportunities both for multi-disciplinary clinical assessment and treatment for manual therapists and for research into the effectiveness of manual therapies.