Three-phase bone scintigraphy for imaging osteoradionecrosis of the jaw

Fluorescence-guided surgery for osteoradionecrosis of the jaw: a retrospective study

OBJECTIVE

Osteoradionecrosis of the jaw (ORNJ) is one of the most severe head and neck complications in patients treated with radiotherapy. The goal of treatment is to suppress ORNJ progression. Currently, surgical removal of necrotic bone is an effective management approach for advanced stages. In this study, we present our experience in managing ORNJ using fluorescence-guided surgery.

METHODS

Nineteen ORNJ lesions in 15 hospitalized patients were treated with fluorescence-guided surgery. We retrospectively reviewed patients' demographic data, comorbidities, local preceding event, location, ORNJ stage, and treatment outcomes with a median follow-up of 12 months.

RESULTS

Twelve lesions (63%) were treated surgically under tetracycline fluorescence, and seven lesions (37%) were surgically treated under auto-fluorescence. Overall, four lesions (21%) achieved complete mucosal healing, eight lesions (42%) showed partial mucosal healing with bone exposure and no signs or symptoms of inflammation, and seven lesions (37%) were progressive. The results showed that either healing or ORNJ stabilization was achieved in 63% of lesions (n = 12).

CONCLUSION

Fluorescence-guided surgery can be beneficial in curing or stabilizing ORNJ. However, randomized clinical trials are needed to confirm these findings.

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.

Evaluation of SPECT/CT in the assessment of inflammatory jaw pathologies

PURPOSE

Since accurate diagnosis of inflammatory jaw diseases is still challenging, this study investigated the performance of three phase bone scintigraphy including SPECT/CT in the assessment of correct diagnosis and size of the affected bone tissue.

METHOD

This retrospective study contained 31 patients with suspected jaw-related osteoradionecrosis, osteomyelitis or medication-related osteonecrosis of the jaw, which underwent 3-phase bone scintigraphy including SPECT/CT. Results were reviewed by two nuclear medicine physicians. Positive cases received surgery; negative ones were followed-up for six months. Both served as reference standard. Inflamed bone length was measured in the SPECT/CT images and postoperatively by a pathologist.

RESULTS

19 out of 20 positive cases and 10 out of 11 negative ones were classified correctly by SPECT/CT (sensitivity 95 %, specificity 91 %, accuracy 94 %, positive predictive value 95 %, negative predictive value 91 %). Regarding the length of affected bone, no significant difference (p = 0.23) could be observed between SPECT/CT and postoperative obtained values. Both correlated significantly (r = 0.86, p = 0.0001).

CONCLUSION

SPECT/CT can safely detect different kinds of inflammatory jaw pathologies compared to other conventional imaging modalities. Lack of specificity of conventional scintigraphy ranging from 17 % to 71 % in earlier studies could be improved by adding CT-analysis. Additionally, SPECT/CT assists the surgeon in determining the expansion of the process (with focus on the length) preoperatively and thereby optimizing surgery planning.

☆Symposium: Imaging modalities for drug-related osteonecrosis of the jaw (5), utility of bone scintigraphy and 18F-FDG PET/CT in early detection and risk assessment of medication-related osteonecrosis of the jaw (secondary publication)

Medication-related osteonecrosis of the jaw (MRONJ) is a significant side effect of antiresorptive and antiangiogenic drugs. Since MRONJ is intractable, early detection is the best way to limit progression. Bone scintigraphy and ¹⁸F- fluorodeoxyglucose positron-emission tomography can detect minimal and subclinical changes in bones earlier than conventional radiological modalities. A differential diagnosis including MRONJ is recommended when abnormally high uptakes are incidentally detected in the jaws of patients who have bone metastases. Quantitative analysis of uptakes, such as bone scan index of the jaw using neural network analysis and maximum standardized uptake value, could differentiate MRONJ from common dental diseases and be useful for the early detection and risk assessment of MRONJ.

Comparative evaluation of SPECT/CT and CBCT in patients with mandibular osteomyelitis and osteonecrosis

OBJECTIVES

Therapy of osteomyelitis and osteonecrosis very often requires surgery. Proper preoperative radiological evaluation of a lesion's localization and extent is a key in planning surgical bone resection. This study aims to assess the differences between single-photon emission computed tomography and cone beam computed tomography when detecting an osteomyelitis/osteonecrosis lesion as well as the lesion's qualitative parameters, extent, and localization.

MATERIAL AND METHODS

Identification of candidates was performed retrospectively following a search for patients with histologically or clinically confirmed osteomyelitis or osteonecrosis. They were matched with a list of patients whose disease extent and localization had been evaluated using single-photon emission computed tomography and cone beam computed tomography in the context of clinical investigations. Subsequently, two experienced examiners for each imaging technique separately performed de novo readings. Detection rate, localization, extent, and qualitative parameters of a lesion were then compared.

RESULTS

Twenty-one patients with mandibular osteomyelitis and osteonecrotic lesions were included. Cone beam computed tomography detected more lesions than single-photon emission computed tomography (25 vs. 23; 100% vs. 92%). Cone beam computed tomography showed significantly greater depth, area, and volume, whereas length and width did not differ statistically between the two groups.

CONCLUSION

Both single-photon emission computed tomography and cone beam computed tomography could sensitively detect osteomyelitis/osteonecrosis lesions. Only single-photon emission computed tomography showed metabolic changes, whereas cone beam computed tomography seemed to display anatomic morphological reactions more accurately. The selection of the most adequate three-dimensional imaging and the correct interpretation of preoperative imaging remains challenging for clinicians.

CLINICAL RELEVANCE

In daily clinical practice, three-dimensional imaging is an important tool for evaluation of osteomyelitis/osteonecrosis lesions. In this context, clinicians should be aware of differences between single-photon emission computed tomography and cone beam computed tomography when detecting and assessing an osteomyelitis/osteonecrosis lesion, especially if a surgical bone resection is planned.

Chemical and Radiation-Associated Jaw Lesions

Osteonecrosis of the jaw is a major public health concern throughout the world. Use of radiotherapy for head and neck cancer and bone antiresorptives and antiangiogenic agents have increased its incidence. Medication-related osteonecrosis of the jaw is more common relative to other types of osteonecrosis. Osteoradionecrosis occurs despite better treatment planning and shielding to minimize collateral damage to bone. Other related necrotic lesions are secondary to usage of recreational drugs and steroids. This article provides comprehensive information about these different types of bone necrosis; provides the readers with radiographic diagnostic criteria and updates on current theories on pathophysiology of osteonecrosis.

Bone scintigraphy predicts bisphosphonate-induced osteonecrosis of the jaw (BRONJ) in patients with metastatic castration-resistant prostate cancer (mCRPC)

OBJECTIVES

The aim of this study was to evaluate the role of bone scintigraphy (BS) in early prediction of clinically asymptomatic bisphosphonate (BP)-related osteonecrosis of the jaws (BRONJ) in patients with metastatic castration-resistant prostate cancer (mCRPC).

MATERIAL AND METHODS

BS of mCRPC patients treated with BP was evaluated for pathologic tracer uptake of the jaws in BS suspicious for BRONJ. Results were compared to development of clinically evident BRONJ. Sensitivity, specificity and predictive values of BS for the detection of BRONJ as well as time from beginning of BP therapy to pathologic tracer uptake in BS and time from pathologic tracer uptake in BS to clinically evident BRONJ were determined.

RESULTS

Thirty BP-treated patients were included. Nine patients (30%) had pathologic BS lesions of the jaws. Six patients (20%) developed BRONJ. Sensitivity and specificity of BS for BRONJ prediction were 67 and 79%. Median time from the start of BP treatment to pathologic tracer uptake in BS was 28 months (range 10-33) and from pathologic tracer uptake in BS to clinically evident BRONJ 6.5 months (range 2-19). Pathologic tracer uptake in BS was significantly more often observed in patients who developed BRONJ compared to patients who did not (p = 0.049; OR 7.6).

CONCLUSIONS

Patients with pathologic tracer uptake in the jaws in BS significantly more often develop BRONJ. An unsuspicious BS is predictive for absence of BRONJ in the future.

CLINICAL RELEVANCE

We conclude that when BS has been performed, it should not only be used to assess tumour stage and treatment response but also to check for pathologic tracer uptake in the jaws in BS to detect BRONJ at an early stage in mCRPC patients receiving bisphosphonates.

Intraindividual comparison of preoperative (99m)Tc-MDP SPECT/CT and intraoperative and histopathological findings in patients with bisphosphonate- or denosumab-related osteonecrosis of the jaw

PURPOSE

Bisphosphonate- or denosumab-related osteonecrosis of the jaw (BRONJ/DRONJ) requires reliable preoperative assessment of the extent of disease for surgical planning. The aim of this study was to compare the extent of BRONJ/DRONJ as detected by Tc-99m-methylene diphosphonate (MDP) bone scintigraphy with intraoperative and histopathological findings, and to assess the additional value of hybrid single photon emission computed tomography/computed tomography (SPECT/CT) for evaluation of disease.

MATERIAL AND METHODS

Twenty-one patients with BRONJ/DRONJ underwent three-phase bone scintigraphy including SPECT/CT. The diagnostic certainty using conventional SPECT or fused SPECT/CT imaging was compared. Location and extent of disease on scintigraphic imaging and pre- and intra-operative clinical assessment were compared. Intraoperative and histopathological findings served as reference standard.

RESULTS

A total of 29 sites of BRONJ/DRONJ were histopathologically confirmed in 21 patients. Bone scintigraphy demonstrated increased perfusion in 57.1% of patients, increased blood pool in 76.2%, and increased tracer accumulation at the metabolic phase in all patients. The intensity of tracer accumulation at the metabolic phase correlated significantly with clinical stage of disease (rs = 0.47, p = 0.03). Clinical examination (p < 0.0001), but not SPECT (p = 0.19), underestimated the extent of disease as determined by surgical evaluation. SPECT/CT offered a significantly higher diagnostic certainty (p < 0.0001).

CONCLUSION

In patients with BRONJ/DRONJ, the true extent of osseous lesions as determined by surgery is significantly underestimated by clinical examination. Tc-99m-MDP bone scintigraphy can reliably predict the extent of disease. Hybrid SPECT/CT may significantly increase the diagnostic certainty of anatomical localization.