{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T16:21:51Z","timestamp":1772468511029,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T00:00:00Z","timestamp":1772409600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Tomography"],"abstract":"<jats:p>Background\/Objectives: Skull base osteomyelitis and necrotising otitis externa require prolonged antibiotic therapy, yet determining optimal treatment cessation timing remains challenging. Conventional imaging modalities demonstrate persistent abnormalities beyond infection resolution, confounding treatment decisions. This systematic review evaluated the diagnostic test accuracy of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) for treatment response monitoring in skull base osteomyelitis and necrotising otitis externa. Methods: We conducted a systematic review following PRISMA-DTA guidelines, searching MEDLINE, Embase, CENTRAL, CINAHL, Scopus, and Web of Science from inception to November 2025. Studies evaluating 18F-FDG PET diagnostic accuracy for treatment response assessment in confirmed skull base osteomyelitis or necrotising otitis externa were included. Two reviewers independently screened studies, extracted data, and assessed risk of bias using QUADAS-2. Bivariate random-effects meta-analysis was performed using MetaBayesDTA to obtain pooled sensitivity and specificity. Results: Eight studies comprising 154 lesions contributed to the primary analysis. Pooled sensitivity was 95.2% (95% credible interval 85.6\u201399.0%) and pooled specificity was 89.1% (95% credible interval 70.7\u201396.7%). The positive likelihood ratio was 8.7 (95% credible interval 3.2\u201328.4) and negative likelihood ratio was 0.05 (95% credible interval 0.01\u20130.17), with a diagnostic odds ratio of 172.0. Seven studies evaluating detection rate at initial presentation yielded a pooled rate of 96.1% (95% confidence interval 91.3\u201398.3%). SUVmax was the most frequently used metabolic parameter. Conclusions: 18F-FDG PET, specifically using SUVmax, demonstrates high sensitivity and good specificity for treatment response monitoring, with excellent capacity to rule out persistent infection. However, evidence quality is limited by retrospective designs and substantial heterogeneity. Prospective studies with standardised thresholds are needed to validate clinical utility.<\/jats:p>","DOI":"10.3390\/tomography12030032","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:55:01Z","timestamp":1772463301000},"page":"32","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Diagnostic Test Accuracy and Semi-Quantitative Metrics of 18F-FDG PET in Assessing Treatment Response in Skull Base Osteomyelitis and Necrotising Otitis Externa: A Systematic Review and Meta-Analysis"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-6444-7876","authenticated-orcid":false,"given":"Mark","family":"Laidlaw","sequence":"first","affiliation":[{"name":"Department of Otolaryngology, Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maya","family":"Reid","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Head and Neck Surgery, Canberra Health Service, Canberra, ACT 2605, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sukanya","family":"Rajiv","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9144-9377","authenticated-orcid":false,"given":"Jean-Marc","family":"Gerard","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia"},{"name":"Victorian Cochlear Implant Program, Royal Victorian Eye and Ear Hospital, Melbourne, VIC 3002, Australia"},{"name":"Department of Otolaryngology, University of Melbourne, Melbourne, VIC 3010, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,2]]},"reference":[{"key":"ref_1","unstructured":"Hohman, M.H., and Kelley, C. (2025, December 17). Necrotizing (Malignant) Otitis Externa, StatPearls, Available online: http:\/\/www.ncbi.nlm.nih.gov\/books\/NBK556138\/."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1097\/MOO.0000000000000745","article-title":"Current management of skull base osteomyelitis","volume":"29","author":"Auinger","year":"2021","journal-title":"Curr. Opin. Otolaryngol. Head Neck Surg."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"306","DOI":"10.1111\/j.1469-0691.2010.03231.x","article-title":"Skull-base osteomyelitis: Fungal vs. bacterial infection","volume":"17","author":"Blyth","year":"2011","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1007\/s10143-020-01254-x","article-title":"Skull base osteomyelitis: Clinical and radiologic analysis of a rare and multifaceted pathological entity","volume":"44","author":"Schreiber","year":"2021","journal-title":"Neurosurg. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1300","DOI":"10.1177\/00034894221147806","article-title":"Central Skull Base Osteomyelitis: A Case Series from a Tertiary Care Center over 5 Years","volume":"132","author":"Fenberg","year":"2023","journal-title":"Ann. Otol. Rhinol. Laryngol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1111\/coa.14041","article-title":"Systematic review of the diagnosis and management of necrotising otitis externa: Highlighting the need for high-quality research","volume":"48","author":"Takata","year":"2023","journal-title":"Clin. Otolaryngol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"98","DOI":"10.5152\/iao.2020.7709","article-title":"Malignant Otitis Externa: Causes for Various Treatment Responses","volume":"16","author":"Arsovic","year":"2020","journal-title":"J. Int. Adv. Otol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1004","DOI":"10.1097\/MAO.0000000000002723","article-title":"Necrotizing Otitis Externa: A Systematic Review and Analysis of Changing Trends","volume":"41","author":"Byun","year":"2020","journal-title":"Otol. Neurotol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1097\/MAO.0b013e3182804aee","article-title":"Necrotizing Otitis Externa: A Systematic Review","volume":"34","author":"Mahdyoun","year":"2013","journal-title":"Otol. Neurotol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1017\/S0022215100101562","article-title":"The diagnostic criteria of malignant external otitis","volume":"101","author":"Cohen","year":"1987","journal-title":"J. Laryngol. Otol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1148\/rg.2021200046","article-title":"Diagnosis of Skull Base Osteomyelitis","volume":"41","author":"Barriga","year":"2021","journal-title":"RadioGraphics"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"102894","DOI":"10.1016\/j.amjoto.2020.102894","article-title":"Malignant otitis externa: An updated review","volume":"42","year":"2021","journal-title":"Am. J. Otolaryngol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"26367","DOI":"10.1038\/s41598-025-11742-z","article-title":"Patient cases with malignant otitis externa at the university clinic of Ludwig Maximilians University Munich from 2009 until 2020","volume":"15","author":"Stocker","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/j.amjoto.2017.05.010","article-title":"Malignant external otitis: The shifting treatment paradigm","volume":"39","author":"Carlton","year":"2018","journal-title":"Am. J. Otolaryngol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1016\/j.otc.2008.01.004","article-title":"Malignant Otitis Externa","volume":"41","author":"Carfrae","year":"2008","journal-title":"Otolaryngol. Clin. N. Am."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1093\/jac\/30.6.745","article-title":"Malignant otitis externa: The therapeutic evolution of a lethal infection","volume":"30","author":"Glamarellou","year":"1992","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/S1473-3099(03)00858-2","article-title":"The changing face of malignant (necrotising) external otitis: Clinical, radiological, and anatomic correlations","volume":"4","author":"Grandis","year":"2004","journal-title":"Lancet Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1097\/MOO.0000000000000747","article-title":"Skull base osteomyelitis imaging","volume":"29","author":"Singhal","year":"2021","journal-title":"Curr. Opin. Otolaryngol. Head Neck Surg."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4681","DOI":"10.1007\/s00405-020-06576-6","article-title":"The challenging diagnosis and follow-up of skull base osteomyelitis in clinical practice","volume":"278","author":"Auinger","year":"2021","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"404","DOI":"10.3174\/ajnr.A7015","article-title":"Skull Base Osteomyelitis: A Comprehensive Imaging Review","volume":"42","author":"Chapman","year":"2021","journal-title":"Am. J. Neuroradiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1097\/MNM.0000000000001847","article-title":"18F-FDG PET imaging for treatment response assessment and management guidance in patients with skull base osteomyelitis","volume":"45","author":"Saxena","year":"2024","journal-title":"Nucl. Med. Commun."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Gao, H., Li, G., Fu, C., Ren, J., Kang, F., Luo, W., Yin, Q., Zhou, C., Li, B., and Lu, S. (2024). Comparison of diagnostic efficacy between 99mTc-methylene diphosphate SPECT\/CT and MRI for bone and joint infections: A multicenter retrospective analysis. Front. Endocrinol., 15.","DOI":"10.3389\/fendo.2024.1359655"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"S300","DOI":"10.1016\/j.jacr.2025.02.026","article-title":"ACR Appropriateness Criteria\u00ae Inflammatory Ear Disease","volume":"22","author":"Agarwal","year":"2025","journal-title":"J. Am. Coll. Radiol."},{"key":"ref_24","first-page":"2464","article-title":"The Accuracy of Diagnostic Imaging for the Assessment of Chronic Osteomyelitis: A Systematic Review and Meta-Analysis","volume":"87","author":"Termaat","year":"2005","journal-title":"J. Bone Jt. Surg. Am."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1812","DOI":"10.1002\/lary.28411","article-title":"Meta-analysis does not support routine traditional nuclear medicine studies for malignant otitis","volume":"130","author":"Moss","year":"2020","journal-title":"Laryngoscope"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Yang, M., Tan, Q., and Tang, Z. (2024). Bones on fire: Illuminating osteomyelitis through the radiant lens of 18F-FDG PET\/CT. Front. Immunol., 15.","DOI":"10.3389\/fimmu.2024.1378409"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"S473","DOI":"10.1016\/j.jacr.2022.09.013","article-title":"ACR Appropriateness Criteria\u00ae Suspected Osteomyelitis, Septic Arthritis, or Soft Tissue Infection (Excluding Spine and Diabetic Foot): 2022 Update","volume":"19","author":"Pierce","year":"2022","journal-title":"J. Am. Coll. Radiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3310\/hta23610","article-title":"Imaging tests for the detection of osteomyelitis: A systematic review","volume":"23","author":"Llewellyn","year":"2019","journal-title":"Health Technol. Assess."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.foot.2013.07.002","article-title":"Diagnostic performance of Fluorine-18-Fluorodeoxyglucose positron emission tomography for the diagnosis of osteomyelitis related to diabetic foot: A systematic review and a meta-analysis","volume":"23","author":"Treglia","year":"2013","journal-title":"Foot"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1134","DOI":"10.1097\/MNM.0b013e32834b455c","article-title":"A meta-analysis of fluorodeoxyglucose-positron emission tomography versus scintigraphy in the evaluation of suspected osteomyelitis","volume":"32","author":"Wang","year":"2011","journal-title":"Nucl. Med. Commun."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1097\/MNM.0000000000001187","article-title":"In the evaluation of patients with skull base osteomyelitis, does 18F-FDG PET CT have a role?","volume":"41","author":"Kulkarni","year":"2020","journal-title":"Nucl. Med. Commun."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"388","DOI":"10.1001\/jama.2017.19163","article-title":"Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement","volume":"319","author":"McInnes","year":"2018","journal-title":"JAMA"},{"key":"ref_33","unstructured":"Deeks, J., Bossuyt, P., and Leeflang, M. (2025, November 01). Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy, Available online: https:\/\/training.cochrane.org\/handbook-diagnostic-test-accuracy\/current."},{"key":"ref_34","unstructured":"Veritas Health Innovation (2025). Covidence Systematic Review Software, Veritas Health Innovation. Available online: https:\/\/www.covidence.org."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Freeman, S.C., Kerby, C.R., Patel, A., Cooper, N.J., Quinn, T., and Sutton, A.J. (2019). Development of an interactive web-based tool to conduct and interrogate meta-analysis of diagnostic test accuracy studies: MetaDTA. BMC Med. Res. Methodol., 19.","DOI":"10.1186\/s12874-019-0724-x"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1002\/jrsm.1439","article-title":"Graphical enhancements to summary receiver operating characteristic plots to facilitate the analysis and reporting of meta-analysis of diagnostic test accuracy data","volume":"12","author":"Patel","year":"2021","journal-title":"Res. Synth. Methods"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Cerullo, E., Sutton, A.J., Jones, H.E., Wu, O., Quinn, T.J., and Cooper, N.J. (2023). MetaBayesDTA: Codeless Bayesian meta-analysis of test accuracy, with or without a gold standard. BMC Med. Res. Methodol., 23.","DOI":"10.1186\/s12874-023-01910-y"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1187","DOI":"10.1016\/j.jclinepi.2010.08.010","article-title":"Conducting quantitative synthesis when comparing medical interventions: AHRQ and the Effective Health Care Program","volume":"64","author":"Fu","year":"2011","journal-title":"J. Clin. Epidemiol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"196","DOI":"10.1097\/XEB.0000000000000065","article-title":"Fixed or random effects meta-analysis? Common methodological issues in systematic reviews of effectiveness","volume":"13","author":"Tufanaru","year":"2015","journal-title":"Int. J. Evid. Based Healthc."},{"key":"ref_40","unstructured":"R Core Team (2017). R: A Language and Environment for Statistical Computing, R Foundation for Statistical Computing. Available online: https:\/\/www.R-project.org\/."},{"key":"ref_41","unstructured":"Schwarzer, G. (2025, December 04). Meta: General Package for Meta-Analysis. Available online: https:\/\/CRAN.R-project.org\/package=meta."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"529","DOI":"10.7326\/0003-4819-155-8-201110180-00009","article-title":"QUADAS-2: A Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies","volume":"155","author":"Whiting","year":"2011","journal-title":"Ann. Intern. Med."},{"key":"ref_43","unstructured":"(2025, December 01). The Oxford Levels of Evidence 2. Available online: https:\/\/www.cebm.ox.ac.uk\/resources\/levels-of-evidence\/ocebm-levels-of-evidence\/."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"19160216241288810","DOI":"10.1177\/19160216241288810","article-title":"Head-to-Head Comparison Between 18F-FDG PET and Leukocyte Scintigraphy to Monitor Treatment Responses in Necrotizing Otitis Externa","volume":"53","author":"Hurstel","year":"2024","journal-title":"J. Otolaryngol.-Head Neck Surg."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1097\/MAO.0000000000004402","article-title":"Treatment Response Evaluation in Necrotizing Otitis Externa Using 18F-FDG-PET Imaging","volume":"46","author":"Jansen","year":"2025","journal-title":"Otol. Neurotol."},{"key":"ref_46","first-page":"961","article-title":"18- FDG PET in the Evaluation of Therapeutic Response of Necrotizing Otitis Externa","volume":"136","author":"Toulemonde","year":"2025","journal-title":"Laryngoscope"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"961","DOI":"10.1002\/lary.27526","article-title":"FDG-PET\/CT for diagnosis and follow-up of necrotizing (malignant) external otitis","volume":"129","author":"Bernstine","year":"2019","journal-title":"Laryngoscope"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1007\/s00405-024-09006-z","article-title":"Deciding treatment end point in necrotizing otitis externa: Validation of a standardized clinical response assessment strategy with positron emission tomography findings","volume":"282","author":"Thanneru","year":"2025","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1111\/coa.13528","article-title":"99m Tc-HMPAO-leucocyte scintigraphy and [18F]FDG-PET\/CT for diagnosis and therapy monitoring in eleven patients with skull base osteomyelitis","volume":"45","author":"Vion","year":"2020","journal-title":"Clin. Otolaryngol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"e042","DOI":"10.1097\/ONO.0000000000000042","article-title":"Management and Outcomes of Necrotizing Otitis Externa: A Retrospective Cohort Study in a Tertiary Referral Center","volume":"3","author":"Vosbeek","year":"2023","journal-title":"Otol. Neurotol. Open"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1911","DOI":"10.4103\/0028-3886.359218","article-title":"Central Skull Base Osteomyelitis: Multimodality Imaging and Clinical Findings from a Large Indian Cohort","volume":"70","author":"Maramattom","year":"2022","journal-title":"Neurol. India"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"2532","DOI":"10.1093\/jac\/dkac193","article-title":"Necrotizing external otitis: Analysis of relapse risk factors in 66 patients managed during a 12 year period","volume":"77","author":"Danjou","year":"2022","journal-title":"J. Antimicrob. Chemother."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1002\/jrsm.1411","article-title":"Risk-of-bias VISualization (robvis): An R package and Shiny web app for visualizing risk-of-bias assessments","volume":"12","author":"McGuinness","year":"2021","journal-title":"Res. Synth. Methods"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Meyer, M., Testart, N., Jreige, M., Kamani, C., Moshebah, M., Muoio, B., Nicod-Lalonde, M., Schaefer, N., Giovanella, L., and Prior, J.O. (2019). Diagnostic Performance of PET or PET\/CT Using 18F-FDG Labeled White Blood Cells in Infectious Diseases: A Systematic Review and a Bivariate Meta-Analysis. Diagnostics, 9.","DOI":"10.3390\/diagnostics9020060"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"e480","DOI":"10.1097\/MAO.0000000000004777","article-title":"Optimizing Necrotizing Otitis Externa Management: The Role of PET-CT in Antibiotic Stewardship","volume":"47","author":"Zammit","year":"2025","journal-title":"Otol. Neurotol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"691","DOI":"10.1016\/j.bjorl.2020.09.012","article-title":"Comparative study of reliability of inflammatory markers over 18-FDG\u2212PET CT scan in monitoring skull base osteomyelitis","volume":"88","author":"Faizal","year":"2022","journal-title":"Braz. J. Otorhinolaryngol."},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Dondi, F., Albano, D., Treglia, G., and Bertagna, F. (2022). Could [18F]FDG PET\/CT or PET\/MRI Be Useful in Patients with Skull Base Osteomyelitis?. Diagnostics, 12.","DOI":"10.3390\/diagnostics12092035"}],"container-title":["Tomography"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2379-139X\/12\/3\/32\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T15:39:55Z","timestamp":1772465995000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2379-139X\/12\/3\/32"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,2]]},"references-count":57,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,3]]}},"alternative-id":["tomography12030032"],"URL":"https:\/\/doi.org\/10.3390\/tomography12030032","relation":{},"ISSN":["2379-139X"],"issn-type":[{"value":"2379-139X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,2]]}}}