Quantitative SPECT/CT imaging for medication-related osteonecrosis of the jaw: a preliminary study using volume-based parameters, comparison with chronic osteomyelitis

Comparison of single photon emission computed tomography-computed tomography, computed tomography and magnetic resonance imaging of medication-related osteonecrosis of jaw by new calculated parameters

BACKGROUND

This study aimed to investigate parameters for medication-related osteonecrosis of jaw (MRONJ) patients using the bone SPECT/CT, especially bone mineral-based parameters.

METHODS

Sixty-three patients with MRONJ (43 osteoporosis and 20 bone metastasises) underwent CT, MRI and SPECT/CT. A commercially available software automatically detected lesion area and calculated the quantitative SPECT/CT parameters as bone mineral-based standardized uptake value (SUV).

RESULTS

Regarding stage of MRONJ patients, bone mineral based maximum SUV of stage 3 was significantly higher than stage 1, 2 (P=0.018). Regarding duration of medication therapy, bone mineral based maximum SUV 1 year or more was significantly higher than less than 1 year (P=0.019). Regarding present of periosteal bone proliferation on CT, bone mineral based maximum SUV was significantly higher than those of absent (P=0.029). Regarding spread of soft tissue inflammation on MRI, bone mineral based maximum SUV of 2 or more was significantly higher than those of less than 2 spaces (P=0.025). Regarding blood pool phase imaging with SPECT, bone mineral based maximum SUV of intense uptake was significantly higher than those of decrease uptake (P=0.002).

CONCLUSIONS

SPECT/CT bone mineral-based parameters indicated significant difference in staging, dosing period, periosteal bone proliferation on CT, spread of soft tissue inflammation on MRI, and blood phase imaging with SPECT. Bone SPECT/CT bone mineral-based parameters are helpful for the assessment of MRONJ.

Maximum and mean standardized uptake values of medication-related osteonecrosis of the jaw with bone SPECT/CT: comparison of mandibular pathologies, control and temporomandibular joints

OBJECTIVE

Recently, single-photon emission CT/CT (SPECT/CT) plays an important role in assessing patients with medication-related osteonecrosis of the jaw (MRONJ). The aim of this study was to investigate maximum and mean standardized uptake values (SUVs) of MRONJ with bone SPECT/CT, especially comparison of mandibular pathologies, control and temporomandibular joints.

METHODS

61 mandibular patients with MRONJ who underwent bone SPECT/CT were included in this study. The maximum and mean SUVs of the lesion, right and left sides of the lesion, opposite side of the lesion as control, right and left temporomandibular joints were analyzed using a workstation and software. The SUVs of MRONJ were analyzed using one-way analysis of variance with Tukey's honestly significant difference test. Patient characteristics with MRONJ and SUVs were analyzed using Mann-Whitney U test. P-values less than 0.05 were considered to indicate statistical significance.

RESULTS

The maximum and mean SUVs for opposite side of the lesions (4.4 ± 2.0 and 1.8 ± 0.7) were significantly lower than those for mandibular lesions (18.3 ± 8.1 and 6.3 ± 2.8), right side of the lesions (8.1 ± 3.9 and 2.9 ± 1.3) and left side of the lesions (8.1 ± 3.9 and 2.8 ± 1.4), respectively. The maximum and mean SUVs for right and left sides of the lesions, and opposite side of the lesions, right and left temporomandibular joints were not significant difference. Furthermore, the maximum SUVs of the mandibular lesions were a significant difference for age and staging.

CONCLUSIONS

The maximum and mean SUVs with SPECT/CT can be useful in the quantitative management of MRONJ patients.

Usefulness of quantitative bone SPECT/CT for evaluating medication-related osteonecrosis of the jaw treatment response

OBJECTIVE

For assessment of therapeutic response in medication-related osteonecrosis of the jaw (MRONJ) cases, the clinical usefulness of quantitative bone single-photon computed tomography-computed tomography (SPECT/CT) results was investigated.

MATERIALS AND METHODS

Sixteen patients (18 lesions) with a clinical diagnosis of MRONJ underwent bone SPECT/CT scanning before and during/after anti-inflammatory therapy given for 3 or more months. The GI-BONE software package was used to determine standard uptake values (SUVs), including maximum (SUVmax), peak (SUVpeak), and mean (SUVmean), and metabolic bone volume (MBV) and also total bone uptake (TBU). In both responders (downstage) and non-responders (upstage or no change), differences in quantitative values between the first and second SPECT/CT examinations were analyzed using a Wilcoxon test.

RESULTS

Following therapy, significant reductions in SUVmax, SUVpeak, SUVmean, MBV and TBU values for 11 lesions were noted in the responders after therapy (p = 0.003, p = 0.006, p = 0.004, p = 0.003, and p = 0.002, respectively). On the other hand, those for the seven lesions in the non-responder group were not significantly different (p = 0.17, p = 0.16, p = 0.26, p = 0.96, and p = 0.12, respectively). Results for SUVmax change showed sensitivity and specificity values of 45.5% and 85.7%, respectively, for differentiating responders from non-responders, with - 37.3% the optimal cutoff value. Those for MBV change were 72.7 and 85.7%, respectively, with - 29.4% the optimal cutoff value. Those for TBU change were 81.8% and 85.7%, respectively, with - 36.3% the optimal cutoff value.

CONCLUSION

The present findings showed that therapeutic response in MRONJ cases could be determined by use of quantitative SUV, MBV, and TBU values based on bone SPECT/CT findings.

Standardized Uptake Values on SPECT/CT: A Promising Alternative Tool for Treatment Evaluation and Prognosis of Metastatic Neuroendocrine Tumours

(1) Background: The aim of our study was to assess the feasibility of 99mTcEDDA/HYNIC-TOC SPECT/CT quantitative analysis in evaluating treatment response and disease progression in patients with NETs. (2) Methods: This prospective monocentric study evaluated 35 SPECT/CT examinations performed on 14 patients with neuroendocrine tumours who underwent a baseline and at least one follow-up 99mTcEDDA/HYNIC-TOC scan as part of their clinical management. The examination protocol included a whole-body scan acquired 2 h after the radiotracer’s administration, with the SPECT/CT performed 4 h post-injection. Images were analyzed by two experienced physicians and patients were classified into response categories based on their changes in SUV values. (3) Results: We evaluated 14 baseline studies and 21 follow-up scans, accounting for 123 lesions. A statistically positive correlation has been found between the SUVmax and SUVpeak values in tumoral lesions (p < 0.05). No correlation has been found between the SUV values and the ki67 proliferation index. Finally, 64.29% patients were classified as SD at the end of the study, with only 14.29% of patients exhibiting PD and 21.43% patients with PR. (4) Conclusions: The quantitative analysis of 99mTcEDDA/HYNIC-TOC SPECT/CT data in patients with neuroendocrine tumours could represent an alternative to 68Ga-DOTA-peptides PET/CT for the monitoring and prognosis of NETs.

Comparison of maximum and mean standardized uptake values of jaw pathologies with bone SPECT/CT: an especial focus on medication-related osteonecrosis of the jaw

OBJECTIVES

To investigate the comparison of maximum and mean standardized uptake values (SUVs) of jaw pathologies with bone Single-photon emission computed tomography/computed tomography (SPECT/CT), and a special focus on medication-related osteonecrosis of the jaw (MRONJ).

METHODS

Eighty-nine patients with jaw pathologies (63 MRONJ, 13 chronic osteomyelitis, 11 osteoradionecrosis and 2 primary intraosseous carcinoma) underwent bone SPECT/CT scans acquisition at 4 h after intravenous injection of Tc-99m hydroxymethylene diphosphonate in this prospective study. The evaluation of mean and maximum SUVs of jaw pathologies were performed using Q. Metrix and Xeleris workstation and defined the data automatically. Statistical analyses were performed by Pearson's correlation coefficient for comparison of maximum and mean SUVs and Mann-Whitney U-test for SUVs of MRONJ. A P value lower than 0.05 was considered to indicate statistical significance.

RESULTS

Maximum SUVs of MRONJ, chronic osteomyelitis, osteoradionecrosis and primary intraosseous carcinoma were 17.6 ± 8.4, 21.7 ± 7.1, 11.9 ± 4.8 and 26.6 ± 7.0, respectively. Mean SUVs of MRONJ, chronic osteomyelitis, osteoradionecrosis and primary intraosseous carcinoma were 10.1 ± 4.9, 11.9 ± 3.3, 7.0 ± 2.8 and 10.1 ± 4.5, respectively. The maximum SUV of jaw pathologies was significantly correlated with the mean SUV (Y = 0.494X + 1.228; R2 = 0.786; P < 0.001). Furthermore, maximum and mean SUVs of MRONJ had significant differences in underlying diseases, medication and staging.

CONCLUSION

The maximum and mean SUVs with bone SPECT/CT can be an effective tool for the quantitative evaluation of jaw pathologies, especially MRONJ.

Preliminary Study for Quantitative Assessment of Sacroiliitis Activity Using Bone SPECT/CT: Comparison of Diagnostic Performance of Quantitative Parameters

Purpose

We compared the feasibility of quantitative analysis methods using bone SPECT/CT with those using planar bone scans to assess active sacroiliitis.

Methods

We retrospectively reviewed whole-body bone scans and pelvic bone SPECT/CTs of 8 patients who had clinically confirmed sacroiliitis and enrolled 24 patients without sacroiliitis as references. The volume of interest of each sacroiliac joint, including both the ilium and sacrum, was drawn. Active arthritis zone (AAZ) was defined as the zone of voxels with higher SUV than sacral mean SUV within the VOI of SI joint. Then, the following SPECT/CT quantitative parameters, SUVmax (maximum SUV), SUV50% (mean SUV in highest 50% of SUV), and SUV-AAZ, and the ratio of those values to sacral mean SUV (SUVmax/S, SUV50%/S, SUV-AAZ/S) were calculated. For the planar bone scan, the mean count ratio of SI joint/sacrum (SI/S) was conventionally measured.

Results

Most of the SPECT/CT parameters of the sacroiliitis group were significantly higher than the normal group, whereas SI/S of the planar bone scan was not significantly different between the two groups. In receiver operating characteristic curve analysis, SUV-AAZ/S showed the highest AUC of 0.992, followed by SUV50%/S and SUVmax/S. All ratio parameters of the SPECT/CT showed higher AUC values than the SUV parameters of SI joint or SI/S of the planar scan.

Conclusions

The quantitative analyses of bone SPECT/CT showed better performance in assessing active sacroiliitis than the planar bone scan. SPECT/CT parameters using the ratio of the SI joint to sacrum showed more favorable results than SUV parameters such as SUVmax, SUV50%, and SUV-AAZ.

Diagnostic performance of quantitative Ga-SPECT/CT for patients with lower-limb osteomyelitis

BACKGROUND

Patients with lower-limb osteomyelitis (LLOM) may experience major adverse events, such as lower-leg amputations or death; therefore, early diagnosis and risk stratification are essential to improve outcomes. Ga-scintigraphy is commonly used for diagnosing inflammatory diseases. Although the diagnostic performance of planar and SPECT imaging for localized lesions is limited, SPECT/CT, which simultaneously acquires functional and anatomical definition, has resulted in significant improvements to diagnostic confidence. While quantitative Ga-SPECT/CT is an emerging approach to improve diagnoses, its diagnostic performance has not been sufficiently evaluated to date. Therefore, this study aimed to evaluate the diagnostic performance of Ga-SPECT/CT with quantitative analyses for patients with LLOM.

METHODS

A total of 103 consecutive patients suspected of LLOM between April 2012 and October 2016 were analyzed. All patients underwent Ga-scintigraphy with SPECT/CT imaging. Findings were assessed visually, with higher than background accumulation considered positive, and quantitatively, using Ga-SPECT/CT images to calculate the lesion-to-background ratio (LBR), the maximum standardized uptake value (SUVmax), and total lesion uptake (TLU). Diagnoses were confirmed using pathological examinations and patient outcomes, and diagnostic performances of planar, SPECT, and SPECT/CT images were compared. To evaluate prognostic performance, all patients were observed for 5 years for occurrences of major adverse events (MAE), defined as recurrence of osteomyelitis, major leg amputation, or fatal event. Multivariate Cox regression was performed to evaluate outcome factors.

RESULTS

The overall diagnoses indicated that 54 out of 103 patients had LLOM. LBR, SUVmax, and TLU were significantly higher in patients with LLOM (12.23 vs. 1.00, 4.85 vs. 1.34, and 68.77 vs. 8.63, respectively; p < 0.001). Sensitivity and specificity were 91% and 96% for SPECT/CT with LBR, 89% and 94% for SPECT/CT with SUVmax, and 91% and 92% for SPECT/CT with TLU, respectively. MAE occurred in 23 of 54 LLOM patients (43%). TLU was found to be an independent prognostic factor (p = 0.047).

CONCLUSIONS

Ga-SPECT/CT using quantitative parameters, namely LBR and TLU, had better diagnostic and prognostic performances for patients with LLOM compared to conventional imaging. The results suggest that Ga-SPECT/CT is a good alternative for diagnosing LLOM in countries where FDG-PET/CT is not commonly available.

Volumetric analysis of mandibular lesions with SPECT/CT: a pilot clinical study of maximum standardized uptake value

Purpose

This study was designed to investigate mandibular lesions using volumetric analysis with bone single-photon emission computed tomography/computed tomography (SPECT/CT).

Material and methods

Eight patients with mandibular lesions underwent SPECT/CT scan acquisition 4 hours after injection of Tc-99m hydroxymethylene diphosphonate (HMDP). Regarding volumetric analysis, maximum standar-dized uptake value (SUV) was obtained using software and a workstation (Q.Volumetrix MI and GEniE-Xeleris 4 DR, respectively). The localization and size of the volume of interest (VOI) can be drawn over the lesion, mesial, distal, and opposite side as normal using the CT, SPECT, and SPECT/CT transaxials, coronals, and sagittals as the anatomical reference. Q.Volumetrix MI can analyse SUV of lesions by organ segmentation using optional pan and zoom imaging. Then, the dosimetry software provided multiple quantitative data for a given VOI. Statistical analyses for the maximum SUV were performed by Mann-Whitney U test. A p-value lower than 0.05 was considered as statistically significant.

Results

Maximum SUVs for medication-related osteonecrosis of the jaw (n = 4, 25.4 ± 4.9), chronic osteomyelitis (n = 3, 14.6 ± 3.1), and squamous cell carcinoma (n = 1, 31.7) were significantly higher than those of the opposite side as normal mandible (3.8 ± 0.7, 4.6 ± 1.8, and 7.4, respectively; p = 0.000).

Conclusions

Volumetric analysis with SPECT/CT could be useful for the evaluation of mandibular lesions, such as detecting and surgical planning.

Diagnosis of prosthetic joint infection at the hip using the standard uptake value of three-phase 99mTc-hydroxymethylene diphosphonate SPECT/CT

PURPOSE

To retrospectively investigate whether the standard uptake value (SUV) of 99mTc-bone single-photon emission computed tomography (SPECT)/CT could be useful for predicting prosthetic joint infection (PJI) at the hip.

PATIENTS AND METHODS

We analyzed the cases of 37 patients with a suspected PJI at the hip who underwent 99mTc-bone SPECT/CT and surgical intervention with pathological and bacterial examinations. We divided the cases into those with and those without a causative bacterium detected in a surgical specimen, i.e., the positive bacterial culture (PBC) group (n = 17) and negative bacterial culture (NBC) group (n = 20). Cases with neutrophilic infiltration of surgical specimen comprised the positive neutrophilic infiltration (PINF) group (n = 18) and those without INF comprised the non-neutrophilic infiltration (NINF) group (n = 19). Quantitative analyses were performed using maximum SUVs and peak SUVs of blood-pool (BP) phase images (SUVmaxBP and SUVpeakBP) and late (LT)-phase images (SUVmaxLT and SUVpeakLT).

RESULTS

Regarding the bacterial cultures, there were significant differences between the PBC and NBC groups in SUVmaxBP (5.26 ± 1.49 vs. 4.21 ± 1.15, respectively; p = 0.019), SUVpeakBP (4.89 ± 1.32 vs. 3.87 ± 1.06, p = 0.012), SUVmaxLT (16.10 ± 6.36 vs. 11.67 ± 4.95, p = 0.026), and SUVpeakLT (14.58 ± 5.83 vs. 10.49 ± 4.31 p = 0.036). Regarding neutrophilic infiltration, there were significant differences between the PINF and NINF groups in SUVmaxBP (5.18 ± 1.48 vs. 4.24 ± 1.19, p = 0.047) and SUVpeakBP (4.78 ± 1.32 vs. 3.92 ± 1.10, p = 0.043).

CONCLUSION

An SUV analysis of 99mTc-bone SPECT/CT is a useful method to differentiate a PJI at the hip from non-infection.

[Management of medication-related osteonecrosis of the jaw-a review of recent study results in comparison to established strategies]

Hintergrund

Antiresorptiva gehören weltweit zu den am häufigsten applizierten Arzneimitteln. Ihr Haupteinsatzbereich liegt in der Osteologie und Onkologie. Trotz allgemein guter Verträglichkeit treten bei Patienten unter Therapie unerwünschte Arzneimittelwirkungen (UAW) auf. Eine spezifische UAW im Bereich der Kiefer ist die sog. medikamentenassoziierte Osteonekrose („medication-related osteonecrosis of the jaw“, MRONJ) der Kiefer.

Ziel der Arbeit

Diese Arbeit stellt neuesten Entwicklungen in Ätiologie, Diagnostik und Therapie der MRONJ im Vergleich zu bereits bestehenden Erkenntnissen zusammen.

Methodik

Es wurde eine systematische Literaturübersicht der Jahre 2016–2021 zu diesem Thema durchgeführt. Prospektive Therapiestudien, Diagnostikstudien mit Vergleichsgruppe und innovative Studien zur Pathogenese der MRONJ wurden eingeschlossen und nach den MINORS-Kriterien („methodological index for non-randomized studies“) bewertet.

Ergebnisse und Diskussion

Die MRONJ tritt bei ca. 2–12 % der Patienten, die aus onkologischer Indikation mit Antiresorptiva behandelt werden, auf (osteologische Indikation ca. 0,1–1 %). Die Therapie der MRONJ sollte frühzeitig und operativ erfolgen. Die Heilungsrate ist bei einem operativen Therapieansatz mit über 85 % sehr gut.

Maximum standardized uptake value of normal structures in the head and neck with bone SPECT/CT

INTRODUCTION

The quantitative parameter was successfully derived from the quantitative bone SPECT/CT images. The aim of this study was to evaluate maximum standardized uptake value (SUV) of normal structures in the head and neck with bone SPECT/CT.

METHODS

Fifty-three patients with jaw lesions (11 chronic osteomyelitis, eight osteoradionecrosis and 34 medication-related osteonecrosis of the jaw) who had bone SPECT/CT were prospectively included. The maximum SUV of normal structures including vertebrae, sternal body, parietal bone and hyoid bone were analysed. Statistical analyses for the maximum SUV were performed by Pearson's rank correlation test. A P value lower than 0.05 was considered statistically significant.

RESULTS

The maximum SUVs of vertebrae, sternal body, parietal bone and hyoid bone of all patients were 8.10 ± 3.72, 5.16 ± 2.05, 3.67 ± 1.55 and 1.44 ± 0.56, respectively. Furthermore, the maximum SUV of vertebrae was significantly correlated with that of sternal body (Y = 0.527X + 5.388 (R²  = 0.084, P = 0.035)).

CONCLUSIONS

Maximum SUV with bone SPECT/CT should be useful for characterization of normal structures in the head and neck. Furthermore, the data reported herein can be used for reference in future studies and in clinical settings for head and neck lesions.

Comparison between planar and single-photon computed tomography images for radiation intensity quantification in iodine-131 scintigraphy

This study aimed to evaluate the feasibility of quantifying iodine-131 (¹³¹I) accumulation in scintigraphy images and compare planar and single-photon emission computed tomography (SPECT) images to estimate ¹³¹I radioactivity in patients receiving radioactive iodine therapy for thyroid cancer. We evaluated 72 sets of planar and SPECT images acquired between February 2017 and December 2018. Simultaneously, we placed a reference ¹³¹I capsule next to the patient during image acquisition. We evaluated the correlation between the intensity of the capsule in the images and the capsule dose and estimated the radiation dose at the thyroid bed. The mean capsule dose was 2.14 MBq (range, 0.63–4.31 MBq). The correlation coefficients (p-value) between capsule dose and maximum and mean intensities in both planar and SPECT images were 0.93 (p < 0.01), 0.96 (p < 0.01), 0.60 (p < 0.01), and 0.47 (p < 0.01), respectively. The mean intensities of planar images show the highest correlation coefficients. Based on a regression equation, the average radiation dose in the thyroid bed was 5.9 MBq. In conclusion, planar images reflected the radiation dose more accurately than SPECT images. The regression equation allows to determine the dose in other regions, such as the thyroid bed or sites of distant metastasis.

Monitoring jaw osteomyelitis therapy with single-photon emission computed tomography/computed tomography

OBJECTIVE

The aim of the study was to evaluate the value of single-photon emission computed tomography/computed tomography (SPECT/CT) for therapy response assessment of jaw osteomyelitis.

MATERIALS AND METHODS

Thirty-four baseline and 74 follow-up SPECT/CT examinations for therapy response assessment were performed in 34 patients with jaw osteomyelitis. SPECT/CT and planar late-phase bone scintigraphy images were assessed at baseline and follow-up, according to the following criteria: tracer uptake grade (0 = no uptake, 1 = low uptake, 2 = moderate uptake and 3 = high uptake); and morphologic signs (osteolysis, sequestration, sclerosis, periosteal reaction and pathologic fracture).

RESULTS

At baseline, SPECT/CT showed marked (grade 2 or 3) uptake in 91% (31/34) of the patients, osteolysis in 85% (29/34), sclerosis in 71% (24/34), periosteal reaction in 44% (15/34) and a sequestrum in 24% (8/34). In 24 patients with clinically complete remission during or after at least 12 months' therapy, bone scintigraphy showed grade 0 or 1 uptake in 100% (24/24) and SPECT/CT in 91% (22/24) of the patients. Sclerosis with the disappearance of osteolysis, sequestration and periosteal reactions was the predominant morphologic finding in complete responders (68%; 16/24). In 10 patients with symptoms of exacerbation of the osteomyelitis, 80% (8/10) showed increasing uptake, 90% (9/10) sclerosis, 80% osteolysis (8/10) and 40% (4/10) osteolysis and periosteal reactions.

CONCLUSION

SPECT/CT is a valuable tool to accurately assess therapy response, disease exacerbation and complications of jaw osteomyelitis. Low-grade (grade 1) residual tracer uptake is common in patients with clinically complete remission and is suggestive of ongoing bone remodeling and healing.

Medication-related osteonecrosis of the jaw in a patient with multiple myeloma: an unusual case with tumor in the surgical specimen

Multiple myeloma is characterized by a neoplastic proliferation of plasma cells primarily in the bone marrow. Neoplastic plasma cells stimulated osteoclasts, and destroy bone tissue, causing bone pain, pathological fractures, paralysis due to spinal cord compression, and hypercalcemia. Bisphosphonates are used as supportive therapy in the management of multiple myeloma. Medication-related osteonecrosis of the jaw (MRONJ) is a well-known complication of treatment with bisphosphonates, denosumab, and other drugs, such as anti-angiogenic agents and novel anti-cancer drugs. We report MRONJ in a patient with multiple myeloma, especially an unusual case with tumor in the surgical specimen. A 73-year-old woman presented with pain on the left side of the mandible within 3 months. On clinical examination, an exposed bone without purulent drainage presented on the left side of the mandible. Before 2 years, she received chemotherapy of zoledronate for multiple myeloma at another hospital. Panoramic imaging showed radiopacities of bone in the left side of the mandibular molar area. Multidetector computed tomography (MDCT) with axial, multiplanar reformation (MPR) and three-dimensional (3D) images showed the sequestrum without periosteal reaction. She was diagnosed as MRONJ, and underwent surgery. Finally, the surgical specimen was diagnosed as multiple myeloma in the sequestrum. This case suggests that the evaluation of the surgical specimen of MRONJ could be essential for detection of primary tumor.

Quantitative Analysis of Multimodal Skeletal SPECT/CT Reconstructions in Diagnosing Medication-related Osteonecrosis of the Jaw

AIM

Our goal was to assess visual and quantitative aspects of multimodal skeletal SPECT/CT reconstructions (recon) in differentiating necrotic and healthy bone of patients with suspected MRONJ.

METHODS

Prior to surgery, 20 patients with suspected MRONJ underwent SPECT/CT of the jaw 3-4 hours after injection of Tc-99m-DPD (622±112.4 MBq). SPECT/CT data were reconstructed using the multimodal xSPECT Bone and xSPECT Quant algorithms as well as the OSEM-algorithm FLASH 3D. For analysis, we divided the jaw into 12 separate regions. Both xSPECT Bone and FLASH 3D datasets were scored on a four-point scale (VIS xSPECT; VIS F3D), based on the intensity of localized tracer uptake. In F3D and xSPECT Quant datasets, local tracer uptake of each region was recorded as semi-quantitative uptake ratio (SQR F3D) or SUVs, respectively. ROC analysis was performed. Postoperative histologic results served as gold standard.

RESULTS

VIS F3D, VIS xSPECT and SQR F3D did not differ significantly in diagnostic accuracy (VIS xSPECT sensitivity=0.64; specificity=0.89). Of the quantitative parameters, SUVpeak yielded the best interobserver reproducibility. SUVpeak was 9.9±7.1 (95%CI: 7.84-11.95) in MRONJ regions, as opposed 3.6±1.8 (95% CI:3.36-3.88) elsewhere, with a cutpoint of 4.5 (sensitivity=0.83; specificity=0.80). Absolute quantitation significantly surpassed VIS and SQR (p<0.05) in accuracy and interobserver agreement (SUVpeak: κ=0.92; VIS xSPECT: κ=0.61; SQR F3D κ=0.66).

CONCLUSION

Absolute quantitation proved significantly more accurate than visual and semi-quantitative assessment in diagnosing MRONJ, with higher interobserver agreement.

A clinical pilot study of salivary gland secretion for xerostomia patients with Sjögren's syndrome using SPECT/CT

INTRODUCTION

This study examined whether time-activity curves (TAC) can be used to differentiate between patients with and without Sjögren's syndrome using SPECT/CT.

METHODS

Thirteen xerostomia patients (5 with Sjögren's syndrome and 8 without Sjögren's syndrome) underwent SPECT/CT. Salivary gland secretion data were digitally observed, producing separate time-activity curves (TAC) for the submandibular glands and parotid glands using SPECT/CT. The salivary gland secretion fraction was defined as A (before stimulation test [counts/frame]) divided by B (after stimulation test [counts/frame]). The A/B ratios of patients with Sjögren's syndrome and those without Sjögren's syndrome were compared using the Mann-Whitney U test for nonparametric data.

RESULTS

The A/B ratio of parotid glands with Sjögren's syndrome (1.3 ± 0.2) was significantly lower than for those without Sjögren's syndrome (2.7 ± 0.7). The A/B ratio of submandibular glands with Sjögren's syndrome (1.3 ± 0.4) is significantly lower than for those without Sjögren's syndrome (1.8 ± 0.6).

CONCLUSION

The TAC for the submandibular glands and parotid glands using SPECT/CT may be useful for the objective and quantitative diagnosis of Sjögren's syndrome.

Effect of morphological findings in computed tomography on the quantitative values in single-photon emission computed tomography for patients with antiresorptive agent-related osteonecrosis of the jaw: a cross-sectional study

OBJECTIVE

Quantitative analyses of gamma-ray accumulation in single-photon emission computed tomography (SPECT), and the evaluation of antiresorptive agent-related osteonecrosis of the jaw (ARONJ) have been reported recently. However, the relationship between the quantitative parameters calculated from SPECT and the detailed morphological changes observed in computed tomography (CT) remains unclear. This study aimed to investigate patients' characteristics and morphological changes observed on CT, and their effects on the quantitative values in SPECT.

METHODS

From April 2017 to March 2019, patients diagnosed with ARONJ at our hospital were enrolled. The data obtained before September 2017 were reviewed retrospectively, and other data were collected prospectively. CT scans were evaluated for internal texture, sequestrum formation, periosteal reaction, cortical perforation, bone expansion, and pathological fracture. For quantitative assessment, the ratio of the maximum standardized uptake value (SUV) to the mean SUV in the temporal bone (rSUVmax) was calculated from SPECT images. The factors affecting rSUVmax were investigated by multiple regression analysis. The statistical significance level was set at α = 0.05.

RESULTS

Overall, 55 lesions of 42 patients (median age and interquartile range, 75 [67-80 years], 27 female) were evaluated. Male sex (p = 0.007) and bilateral location (p < 0.0001) were selected as variables in the multivariate analysis. Adjusted coefficient of determination R2 was 0.59 (p < 0.0001).

CONCLUSION

Sex and horizontal progression of the disease may affect individually calibrated SUVs in SPECT for patients with ARONJ.

Usefulness of Quantitative Bone SPECT/CT for Evaluating Treatment Response in a Patient with Mandibular Osteomyelitis

We report here a case of mandibular osteomyelitis in a 63-year-old female in which quantitative values determined using bone SPECT/CT were useful to evaluate response to antibiotic therapy, hyperbaric oxygen therapy, and sequestomy. After finishing therapy, the chief complaints were well relieved, and posttreatment Tc-99m HMDP bone SPECT/CT examination showed decreased uptake. The maximum standardized uptake value (SUV), peak SUV, mean SUV, metabolic bone volume, and total bone uptake of the untreated lesion were 6.26, 5.16, 3.97, and 11.86 mL and 42.21, respectively, which were decreased to 4.65, 3.90, 2.77, and 9.67 mL and 26.80, respectively, following hyperbaric oxygen therapy and antibiotic administration, and were moreover decreased to 4.28, 3.67, 2.75, and 6.24 mL and 17.19, respectively, after sequestomy. In comparison with pretreatment situation, those parameters were decreased by −25.7, −24.4, −30.2, −18.5, and −36.5%, respectively, following hyperbaric oxygen therapy and antibiotic administration, and moreover by −31.6, −28.9, −30.7, −47.4, and −59.3, respectively, after sequestomy, likely reflecting treatment response. Quantitative bone SPECT/CT may be useful to evaluate bone inflammatory activity and treatment response in a patient with mandibular osteomyelitis.

Analysis of medication-related osteonecrosis of the jaw with bone SPECT/CT: relationship between patient characteristics and maximum standardized uptake value

Objective:

To analyze medication-related osteonecrosis of the jaw (MRONJ) with bone single photon emission computed tomography (SPECT)/CT, especially relationship between patient characteristics and maximum standardized uptake value (SUV).

Methods:

48 patients with MRONJ who underwent bone SPECT/CT were prospectively included. MRONJ patients were included 34 osteoporosis and 14 bone metastases from 6 lung cancer, 6 breast cancer and 2 rectal cancer. The maximum SUV of the MRONJ patient characteristics were analyzed such as gender, location, underlying disease, medication and staging of MRONJ by Mann–Whitney U test. P-values lower than 0.05 indicate significant differences.

Results:

Regarding underlying disease, maximum SUV of patients with osteoporosis (18.69 ± 8.57) were significantly higher than those with bone metastases (12.28 ± 4.32, p = 0.005). Furthermore, maximum SUV of MRONJ was a significant difference for medication (denosumab: 13.62 ± 5.70 and minodronate: 22.98 ± 11.73, p = 0.009) and staging of MRONJ (Stage 2: 15.59 ± 8.06 and Stage 3: 21.51 ± 7.15, p = 0.014).

Conclusion:

Maximum SUV assessed by SPECT/CT was significantly increased in MRONJ patients with osteoporosis and Stage 3. Bone SPECT/CT could be an effective tool for the analysis of MRONJ.

A critical assessment of the medication-related osteonecrosis of the jaw classification in stage I patients: a retrospective analysis

Objectives

It is unclear whether the extent of intraoral mucosa defects in patients with medication-related osteonecrosis of the jaw indicates disease severity. Therefore, this study investigated whether mucosal lesions correlate with the true extent of osseous defects in stage I patients.

Materials and Methods

Retrospectively, all patients with stage I medication-related osteonecrosis of the jaw who underwent surgical treatment between April 2018 and April 2019 were enrolled. Preoperatively, the extent of their mucosal lesions was measured in clinical evaluations, and patients were assigned to either the visible or the probeable bone group. Intraoperatively, the extent of necrosis was measured manually and with fluorescence.

Results

Fifty-five patients (36 female, 19 male) with 86 lesions (46 visible bone, 40 probeable bone) were enrolled. Intraoperatively, the necrotic lesions were significantly larger (P<0.001) than the preoperative mucosal lesions in both groups. A significant (P<0.05) but very weak (R2<0.2) relationship was noted between the extent of the mucosal lesions and the necrotic bone area.

Conclusion

Preoperative mucosal defects (visible or probeable) in patients with medication-related osteonecrosis of the jaw do not indicate the extent of bone necrosis or disease severity.

Test-retest repeatability of quantitative bone SPECT/CT

OBJECTIVE

Technological innovations in single-photon emission computed tomography (SPECT) have enabled a more accurate quantitative evaluation of the uptake, and the standardized uptake value (SUV) can be measured as a semi-quantitative value, as in positron emission tomography. Nevertheless, the reliability of the SUV of bone SPECT has not been well established. The purpose of this study is to evaluate the test-retest repeatability of the SUV of bone SPECT/CT in clinical settings.

METHODS

This prospective study recruited patients with prostate cancer planning to receive bone SPECT/CT for the evaluation of bone abnormality between August 2017 and September 2019. Bone images were acquired twice by an integrated SPECT/CT scanner (Symbia Intevo, Siemens) within a 4- to 10-day interval. The maximum SUV (SUVmax) and peak SUV (SUVpeak) were calculated for the volumes of interests on the normal bone areas, degeneration/fracture lesions, and metastatic lesions. To determine repeatability, we calculated statistical indicators, including intraclass correlation coefficient (ICC), repeatability coefficient (RC), and mean absolute percentage difference (MAPD). For the ICC, the 95% confidential interval (CI) was also calculated, and an ICC of ≥ 0.8 was defined as an almost perfect correlation.

RESULTS

Twelve male patients were enrolled in the study (58-86 years; median, 71 years), and a total of 229 volumes of the interest were included in the analyses. The ICCs were 0.968 [95% CI (0.959, 0.975)] for SUVmax and 0.976 [95% CI (0.969, 0.981)] for SUVpeak. The RCs of the relative difference were 30.7% for SUVmax and 27.6% for SUVpeak, and the MAPDs (± standardized deviation) of all lesions were 12.3 ± 9.9% for SUVmax and 11.5 ± 8.3% for SUVpeak. The RCs and the MAPDs showed comparable value with the previous report regarding repeatability studies on PET.

CONCLUSION

An almost perfect correlation was demonstrated by repeated SUVmax and SUVpeak measured by quantitative integrated SPECT/CT. The quantitative values could be reliable indicators in patient management.

Quantitative bone single-photon emission computed tomography imaging for uninfected nonunion: comparison of hypertrophic nonunion and non-hypertrophic nonunion

BACKGROUND

Recently, a standardized uptake value (SUV) has been used to evaluate bone single-photon emission computed tomography (SPECT). The aim of this study was to investigate quantitative SPECT imaging of uninfected nonunion to compare hypertrophic nonunion and non-hypertrophic nonunion using volume-based parameters.

METHODS

We evaluated 23 patients with uninfected nonunion who underwent SPECT acquisition 3 h after an injection of ^99mTc-hydroxymethylene diphosphonate or ^99mTc-methylene diphosphonate from April 2014 to November 2019. We reconstructed the acquired data and performed voxel-based quantitative analysis using the GI-BONE software. Quantitative parameters, maximum SUV (SUV_max), peak SUV (SUV_peak), and mean SUV (SUV_mean) in the high and low uptake areas of nonunion were compared between hypertrophic nonunion and non-hypertrophic nonunion. The contralateral limb was used as a control, and the ratios of the quantitative parameters were calculated.

RESULTS

The values for the quantitative parameters (high uptake area/low uptake area, respectively), SUV_max control ratio (12.13 ± 4.95/6.44 ± 4.71), SUV_peak control ratio (11.65 ± 4.58/6.45 ± 4.64), and SUV_mean control ratio (11.94 ± 5.03/6.28 ± 4.95) for hypertrophic nonunion were higher than those for non-hypertrophic nonunion (7.82 ± 4.76/3.41 ± 2.09 (p = 0.065/0.12), 7.56 ± 4.51/3.61 ± 2.23 (p = 0.065/0.22), and 7.59 ± 5.18/3.05 ± 1.91 (p = 0.076/0.23)).

CONCLUSIONS

SUV_max, SUV_peak, and SUV_mean control ratios obtained from bone SPECT images can quantitatively evaluate the biological activity of nonunions and may be an effective evaluation method for treatment decisions, especially the necessity of autologous bone grafting.

CBCT imaging and histopathological characteristics of osteoradionecrosis and medication-related osteonecrosis of the jaw

Purpose

The purpose of this study was to evaluate the cone-beam computed tomographic (CBCT) imaging and histopathological characteristics of osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ).

Materials and Methods

Ten surgical specimens from segmental mandibulectomy (3 ORN and 7 MRONJ) were analyzed using CBCT. The CBCT parameters were as follows: high-resolution mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 16.8 s; field of view, 56 mm×56 mm; thickness, 0.099 mm). Histopathological characteristics were evaluated using histological slides of the surgical specimens. The Pearson chi-square test was used to compare ORN and MRONJ in terms of CBCT findings (internal texture, sequestrum, periosteal reaction and cortical perforation) and histopathological characteristics (necrotic bone, inflammatory cells, reactive bone formation, bacteria, Actinomyces, and osteoclasts). A P value less than 0.05 was considered to indicate statistical significance.

Results

MRONJ showed periosteal reaction on CBCT more frequently than ORN (7 of 7 [100%] vs. 0 of 3 [0%], P<0.05). Regarding histopathological characteristics, MRONJ showed osteoclasts more frequently than ORN (6 of 7 [85.7%] vs. 0 of 3 [0%], P<0.05).

Conclusion

This study evaluated the CBCT imaging and histopathological characteristics of ORN and MRONJ, and the findings suggest that CBCT could be useful for the evaluation of ORN and MRONJ.

Bone single-photon emission computed tomography-CT peak standardized uptake value for chronic osteomyelitis, osteoradionecrosis and medication-related osteonecrosis of the jaw

INTRODUCTION

Recently, standardized uptake value (SUV) has been applied for the evaluation of SPECT-CT. This study was performed to investigate the bone SPECT-CT peak SUV for chronic osteomyelitis, osteoradionecrosis and medication-related osteonecrosis of the jaw (MRONJ).

METHODS

Sixty-five patients with jaw lesions (12 chronic osteomyelitis, 12 osteoradionecrosis and 41 MRONJ) underwent SPECT-CT after injection of technetium-99m hydroxymethylene diphosphonate. The peak SUV was compared for the chronic osteomyelitis with osteoradionecrosis and MRONJ using GI-BONE software. Statistical analyses for the peak SUV were performed by one-way repeated measures analysis of variance with Tukey's HSD test. A P-value lower than 0.05 was considered as statistically significant.

RESULTS

Peak SUV for chronic osteomyelitis (15.6 ± 4.4) was significantly higher than those for osteoradionecrosis (6.7 ± 2.1, P = 0.000) and MRONJ (10.7 ± 6.1, P = 0.019).

CONCLUSION

The SPECT-CT peak SUV using GI-BONE software can be useful for the evaluation of jaw lesions, such as chronic osteomyelitis, osteoradionecrosis and MRONJ.

Assessment of SPECT-CT fusion images and semi-quantitative evaluation using SUV in 123I-IMP SPECT in patients with choroidal melanoma

OBJECTIVES

The aim of this study was to assess the diagnostic ability of N-isopropyl-p-[I-123] iodoamphetamine (IMP) SPECT semi-quantitative evaluation based on the standardized uptake value (SUV) in patients with choroidal melanoma. The secondary aim was to investigate the 6-h IMP SPECT imaging in comparison with 24-h imaging.

METHODS

Twenty-five patients (14 males and 11 females, mean age of 59.2-year-old) were analyzed in this retrospective study. Patients underwent 24-h IMP SPECT imaging with a gamma camera after intravenous injection of IMP. Twelve of 25 patients underwent 6-h SPECT imaging in addition to the 24-h imaging. All acquired SPECT images were fused with CT images using an image-analysis software. To assess the utility of semi-quantitative evaluation method, we introduced an image evaluation method using SUVmax comparing with conventional count-based uptake index (UI) evaluation of the lesion. Volumes-of-interest (VOIs) for SUVmax and regions-of-interest (ROIs) for UI were drawn referring to the SPECT-CT fusion image. Then the relationship between the 6- and 24-h images was examined both in SUV and UI evaluation. Furthermore, the relationship between the size category classification (SCC) by UICC/AJCC: 1-4 scales and each semi-quantitative value using SUVmax and UI was also assessed.

RESULTS

SUVmax of the tumor was significantly higher than that of the normal side; 2.37 ± 0.88 and 1.77 ± 0.39 (P < 0.05) on 6-h image, 4.17 ± 1.73 and 2.04 ± 0.45 (P < 0.001) on 24-h image, respectively. UI of the tumor was also significantly higher than that of the normal side; 2.24 ± 0.67 and 1.53 ± 0.35 (P < 0.01) on 6-h image, 3.79 ± 1.24 and 1.67 ± 0.44 (P < 0.001) on 24-h image, respectively. There was a strong significant linear relationship in the evaluation with SUVmax between 6- and 24-h on the tumor side (R² = 0.88, P < 0.0001), compared to that with Tumor-UI (R² = 0.35, P < 0.05). In addition, SUVmax of the tumor clearly differentiated the SCC of the tumor category 4 from that of category 1, where SUVmax of the tumor for categories 1‒4 were 2.56 ± 0.59, 4.33 ± 1.92, 4.63 ± 1.45, and 5.73 ± 1.69, respectively (P < 0.05, for categories 1 and 4).

CONCLUSIONS

The semi-quantitative evaluation by SUV of ¹²³I-IMP SPECT images fused with CT images is useful for detecting choroidal melanoma. Moreover, 6-h imaging with SUV-based evaluation of ¹²³I-IMP SPECT is promising compared to the conventional count-based UI evaluation method. Trial registration This study is registered in UMIN Clinical Trials Registry (UMIN-CTR) as UMIN study ID: UMIN000038174.

Assessment of inflammatory jaw pathologies using bone SPECT/CT maximum standardized uptake value

OBJECTIVES

To investigate the assessment of inflammatory jaw pathologies using bone single-photon emission CT-CT (SPECT/CT) maximum standardized uptake value (SUV_max).

METHODS

44 patients with inflammatory jaw pathologies (7 chronic osteomyelitis, 8 osteoradionecrosis and 29 medication-related osteonecrosis of the jaw (MRONJ)) underwent SPECT/CT at 4 h after injection of ^99mTc hydroxymethylene diphosphonate. The SPECT/CT parameters SUV_max of the inflammatory jaw pathologies were analyzed. Statistical analyses for the SUV_max were performed by one-way repeated measures analysis of variance with Tukey's honestly significant difference test. A p-value lower than 0.05 was considered statistically significant.

RESULTS

The mean and standard deviation of SUV_max for 7 chronic osteomyelitis, 8 osteoradionecrosis and 29 MRONJ were 24.94 ± 3.65, 12.27 ± 5.47 and 16.55 ± 9.12, respectively. The SUV_max for chronic osteomyelitis were significantly higher than those for osteoradionecrosis (p = 0.011) and MRONJ (p = 0.043).

CONCLUSIONS

Bone SPECT/CT SUV_max in the uptake of ^99mTc hydroxymethylene diphosphonate reflecting bone physiological changes for chronic osteomyelitis were significantly higher than those of osteonecrosis, such as osteoradionecrosis and MRONJ. Bone SPECT/CT SUV_max should be useful for the assessment of inflammatory jaw pathologies, such as chronic osteomyelitis, osteoradionecrosis and MRONJ.

Gallium-67 SPECT-CT for the evaluation of head and neck: preliminary study on maximum standardised uptake value in lesions, and in the parotid and submandibular glands

Purpose

The aim of this study was to investigate the gallium-67 (⁶⁷Ga) single-photon emission-computed tomography (SPECT-CT) for the evaluation of head and neck, especially maximum standardised uptake value (SUV_max) in lesions, and in the parotid and submandibular glands.

Material and methods

Fourteen patients with head and neck lesions who underwent SPECT-CT at 72 hours after injection of ⁶⁷Ga were included in this study. The ⁶⁷Ga SPECT-CT parameters SUV_max were compared between the parotid glands and submandibular glands. Statistical analyses for the SUV_max were performed by Mann-Whitney U test. A p value lower than 0.05 was considered as statistically significant.

Results

Of all 14 patients, ⁶⁷Ga SPECT-CT was positive for two cases (one malignant lymphoma and one osteomyelitis). The SUV_max for malignant lymphoma and osteomyelitis were 11.21 and 10.95, respectively. Furthermore, SUV_max for parotid glands and submandibular glands of all patients were 4.86 ± 1.89 and 4.64 ± 1.64, respectively (p = 0.694).

Conclusions

This study investigated the ⁶⁷Ga SPECT-CT for the evaluation of head and neck, especially SUV_max of lesions, and the parotid and submandibular glands. ⁶⁷Ga SPECT-CT may be an effective technique for the evaluation of maxillofacial lesions.

[Evaluation of Post-reconstruction Filtering in Resolution Recovery Reconstruction for Bone SPECT Imaging]

PURPOSE

The aim of this study was to clarify the optimal post-reconstruction filtering type in the three- dimensional ordered subset expectation maximization (3D-OSEM) method for bone single photon emission computed tomography (SPECT) from image quality and quantitative values.

METHOD

We scanned a National Electrical Manufactures Association's body phantom for bone SPECT filled with radioactive solution of ^99mTc whose radioactivity concentration was accurately measured. The SPECT images were created using the 3D-OSEM method. Post-reconstruction filtering was performed using a Butterworth filter (BW), a Gaussian filter (GA), and a Hanning filter (HA) with various parameters. The image quality was evaluated by the normalized mean-squared error (NMSE) value and % of contrast-to-noise ratio (QNR₁₇). The image quality was evaluated by the error values between the measured radioactivity concentration and the true radioactivity concentration in the BG region and insert sphere.

RESULTS

The minimum NMSE values were 0.034 (BW), 0.036 (GA), and 0.035 (HA), and there was no difference depending on the filter type. The values of QNR₁₇ were 2.5 (BW), 2.6 (GA), and 2.6 (HA), and there was no difference depending on the filter type. The BG region was greatly affected by parameter changes in GA but less by those in BW and HA. The error values of the 37 mm insert sphere were 18.0% (BW), 28.2% (GA), and 26.2% (HA), and BW showed the lowest value.

CONCLUSION

Our results suggest that the post-reconstruction filtering type used in the 3D-OSEM method was BW from the image quality and quantitative values.