{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T11:19:32Z","timestamp":1783336772566,"version":"3.54.6"},"reference-count":49,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T00:00:00Z","timestamp":1783123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinics and Practice"],"abstract":"<jats:p>Background\/Objectives: Sinonasal osteomas are benign, slow-growing tumors that are typically asymptomatic and incidentally detected. However, in rare cases, they may present with atypical and potentially serious complications involving other sinonasal, orbital, or intracranial structures. This review aims to synthesize these unusual manifestations and to highlight the underlying mechanisms, diagnostic challenges, and management implications. Methods: A narrative review of the literature was conducted, focusing on reported cases of sinonasal osteomas with rare or complicated presentations. Studies were analyzed with emphasis on clinical features, imaging findings, pathophysiological mechanisms, and treatment strategies. Results: Unusual presentations of sinonasal osteomas are primarily driven by sinus obstruction, progressive expansion, and skull-base erosion. These processes may result in complications such as pneumocephalus, intracranial mucoceles, cerebrospinal fluid leaks, orbital compression, and secondary infections. Clinical manifestations are often nonspecific, including headache, seizures, visual disturbances, or focal neurological deficits, which may delay diagnosis. High-resolution computed tomography is essential for identifying the osseous lesion and associated bone changes, while magnetic resonance imaging is critical for assessing soft-tissue involvement and intracranial extension. Management is individualized, with surgical resection indicated in most symptomatic or complicated cases, using endoscopic, open, or combined approaches. Conclusions: Although rare, atypical manifestations of sinonasal osteomas can result in significant morbidity. A mechanism-based understanding, supported by appropriate imaging, is essential for accurate diagnosis and timely management. Increased clinical awareness is crucial to improving outcomes in these uncommon but clinically significant cases.<\/jats:p>","DOI":"10.3390\/clinpract16070126","type":"journal-article","created":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T08:05:38Z","timestamp":1783325138000},"page":"126","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Unusual Manifestations of Sinonasal Osteomas: A Narrative Review"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0642-6697","authenticated-orcid":false,"given":"Spyridon","family":"Lygeros","sequence":"first","affiliation":[{"name":"Department of Otorhinolaryngology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4430-1361","authenticated-orcid":false,"given":"Alkmini","family":"Gatsounia","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioanna","family":"Athanasiadou","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4162-4261","authenticated-orcid":false,"given":"Aris I.","family":"Giotakis","sequence":"additional","affiliation":[{"name":"First Department of Otorhinolaryngology, Head and Neck Surgery, National and Kapodistrian University of Athens, Hippocrateion General Hospital, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0926-6393","authenticated-orcid":false,"given":"Foteini","family":"Tsapardoni","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, University Hospital of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerasimos","family":"Danielides","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, University of Patras, 26504 Patras, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"102644","DOI":"10.1016\/j.amjoto.2020.102644","article-title":"Management of Paranasal Sinus Osteomas: A Comprehensive Narrative Review of the Literature and an up-to-Date Grading System","volume":"42","author":"Sofokleous","year":"2021","journal-title":"Am. J. Otolaryngol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1016\/j.bjorl.2017.06.010","article-title":"Giant Fronto-Ethmoidal Osteoma\u2014Selection of an Optimal Surgical Procedure","volume":"84","author":"Janik","year":"2018","journal-title":"Braz. J. Otorhinolaryngol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"100094","DOI":"10.1016\/j.omsc.2019.100094","article-title":"Endoscopic Approach for Paranasal Sinuses Osteomas: Our Experience and Review of Literature","volume":"5","author":"Romano","year":"2019","journal-title":"Oral Maxillofac. Surg. Cases"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"600","DOI":"10.2176\/nmc.51.600","article-title":"Frontal Sinus Mucocele With Intracranial Extension Associated With Osteoma in the Anterior Cranial Fossa","volume":"51","author":"Sakamoto","year":"2011","journal-title":"Neurol. Med. Chir."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"100322","DOI":"10.1016\/j.xocr.2021.100322","article-title":"Middle Turbinate Concha Bullosa Osteoma: A Comprehensive Review of All Reported Cases","volume":"20","author":"Araslanova","year":"2021","journal-title":"Otolaryngol. Case Rep."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1016\/j.wneu.2018.12.031","article-title":"Frontal Sinus Osteoma Presenting with Meningitis and Epilepsy","volume":"123","author":"Kolcun","year":"2019","journal-title":"World Neurosurg."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1237","DOI":"10.1007\/s12070-023-04237-8","article-title":"A Giant Frontoethmoidal Ivory Osteoma Causing Cosmetic and Visual Problem: A Case Report","volume":"76","author":"Handa","year":"2024","journal-title":"Indian J. Otolaryngol. Head. Neck Surg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/0090-3019(93)90109-E","article-title":"Giant Intracranial Mucocele Secondary to Osteoma of the Frontal Sinuses: Report of Two Cases and Review of the Literature","volume":"39","author":"Lunardi","year":"1993","journal-title":"Surg. Neurol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2105","DOI":"10.1002\/lary.28299","article-title":"Surgical Treatment of Paranasal Sinus Osteomas: A Single Center Experience of 58 Cases","volume":"130","author":"Wolf","year":"2020","journal-title":"Laryngoscope"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1007\/s00405-010-1447-0","article-title":"A Large Atypical Osteoma of the Maxillary Sinus: A Report of a Case and Management Challenges","volume":"268","author":"Edmond","year":"2011","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"100515","DOI":"10.1016\/j.xocr.2023.100515","article-title":"Ethmoid Osteoma Presenting with Spontaneous Cerebrospinal Fluid Rhinorrhea","volume":"27","author":"Almorsy","year":"2023","journal-title":"Otolaryngol. Case Rep."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"953","DOI":"10.1097\/SCS.0b013e318286885a","article-title":"Frontoethmoid Osteoma With Pneumocephalus: Options for Surgical Management","volume":"24","author":"Harasaki","year":"2013","journal-title":"J. Craniofac. Surg."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"240.e13","DOI":"10.1016\/j.wneu.2012.11.064","article-title":"A Rare Case of Recurrent Frontal Osteoma Complicated by Mucopyocele with an Unusual Organism, Moraxella Catarrhalis","volume":"82","author":"Ramakrishna","year":"2014","journal-title":"World Neurosurg."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"841","DOI":"10.1007\/s00381-010-1356-y","article-title":"A Rare Case of Childhood Hemiparesis","volume":"27","author":"Wu","year":"2011","journal-title":"Childs Nerv. Syst."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"46","DOI":"10.4103\/0971-3026.202972","article-title":"Frontal Sinus Osteoma with Pneumocephalus: A Rare Cause of Progressive Hemiparesis","volume":"27","author":"Umredkar","year":"2017","journal-title":"Indian J. Radiol. Imaging"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"736","DOI":"10.1080\/00207454.2019.1702538","article-title":"Frontotemporal Dementia: An Unusual Cause","volume":"130","author":"Pathak","year":"2020","journal-title":"Int. J. Neurosci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1097\/SCS.0b013e3181f76031","article-title":"A Rare Association of Tension Pneumocephalus and a Large Frontoethmoidal Osteoma: Imaging Features and Surgical Treatment","volume":"22","author":"Guedes","year":"2011","journal-title":"J. Craniofac. Surg."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"658","DOI":"10.4103\/0028-3886.125279","article-title":"Vacuum Sinus Headache: An Uncommon Presentation of a Giant Frontal Osteoma","volume":"61","author":"Krishnan","year":"2013","journal-title":"Neurol. India"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"340","DOI":"10.3171\/jns.2004.101.2.0340","article-title":"Intracerebral Pneumatocele Presenting after Air Travel","volume":"101","author":"Mahabir","year":"2004","journal-title":"J. Neurosurg."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"694","DOI":"10.4103\/0028-3886.125395","article-title":"Frontal Sinus Osteoma with Pneumocephalus and Progressive Hemiparesis","volume":"61","author":"Kendre","year":"2013","journal-title":"Neurol. India"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.1016\/j.jocn.2009.01.016","article-title":"Intraparenchymal Pneumocephalus Caused by Ethmoid Sinus Osteoma","volume":"16","author":"Kamide","year":"2009","journal-title":"J. Clin. Neurosci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1186\/s13256-024-04953-x","article-title":"A Case of Giant Fronto-Ethmoidal Osteoma (45 \u00d7 42 Mm) with Intracranial and Orbital Extension: A Case Report","volume":"18","author":"Dari","year":"2024","journal-title":"J. Med. Case Rep."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"878","DOI":"10.1097\/00006123-200204000-00038","article-title":"Intraparenchymal Tension Pneumatocele Complicating Frontal Sinus Osteoma: Case Report","volume":"50","author":"Johnson","year":"2002","journal-title":"Neurosurgery"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"875","DOI":"10.2176\/nmc.38.875","article-title":"Pneumocephalus Associated with Ethmoidal Sinus Osteoma \u2014Case Report\u2014","volume":"38","author":"Nakayama","year":"1998","journal-title":"Neurol. Med. Chir."},{"key":"ref_25","first-page":"e87707","article-title":"Frontal Sinus Osteoma Causing Tension Pneumocephalus and Acute Hemiparesis: A Rare Neurological Complication","volume":"17","author":"Keshri","year":"2025","journal-title":"Cureus"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1016\/j.otorri.2018.03.006","article-title":"Crisis epil\u00e9ptica por neumoenc\u00e9falo como primera manifestaci\u00f3n de un osteoma etmoido-frontal","volume":"70","author":"Solavera","year":"2019","journal-title":"Acta Otorrinolaringol. Esp."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"bcr-2017-222892","DOI":"10.1136\/bcr-2017-222892","article-title":"The Man That Lost (Part of) His Mind","volume":"2018","author":"Brown","year":"2018","journal-title":"BMJ Case Rep."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1016\/j.wneu.2018.04.071","article-title":"Frontoethmoidal Osteoma with Secondary Intradural Mucocele Extension Causing Frontal Lobe Syndrome and Pneumocephalus: Case Report and Review of Literature","volume":"115","author":"Licci","year":"2018","journal-title":"World Neurosurg."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3094","DOI":"10.1016\/j.radcr.2021.07.038","article-title":"Importance of MRI in the Diagnosis of a Rare Intracranial Mucocele Associated with Frontal Paranasal Osteoma: Case Report and Literature Review","volume":"16","author":"Dedushi","year":"2021","journal-title":"Radiol. Case Rep."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"252","DOI":"10.25259\/SNI_11_2021","article-title":"Intradural Extension of Mucocele Secondary to Giant Frontal Sinus Osteoma: Diagnostic Pitfalls","volume":"12","author":"Ali","year":"2021","journal-title":"Surg. Neurol. Int."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1046\/j.1320-5463.2003.01459.x","article-title":"Osteoma of the Frontal Sinus Complicated by Intracranial Mucocele","volume":"53","author":"Nabeshima","year":"2003","journal-title":"Pathol. Int."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1007\/s00701-003-0202-3","article-title":"Rare Intracranial Manifestations of Frontal Osteomas","volume":"146","author":"Gezici","year":"2004","journal-title":"Acta Neurochir."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"101759","DOI":"10.1016\/j.inat.2023.101759","article-title":"Paranasal Sinus Osteoma with Mucocele: A Case Report and Literature Review","volume":"33","author":"Benali","year":"2023","journal-title":"Interdiscip. Neurosurg."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Samuel, D.M., Manoharan, K.S., and Manohar, M.B. (2024). Giant Osteoma of the Frontal Recess Presenting As Proptosis. J. Maxillofac. Oral Surg.","DOI":"10.1007\/s12663-024-02233-1"},{"key":"ref_35","first-page":"e1296","article-title":"Orbital Cellulitis Secondary to Giant Sino-orbital Osteoma: A Case Report","volume":"4","author":"Bagheri","year":"2021","journal-title":"Cancer Rep."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"\u00d6zt\u00fcrk, N. (2020). \u00c7ocukluk \u00c7a\u011f\u0131nda Nadir Bir Olgu: Frontal Sin\u00fcs Osteomuna \u0130kincil Pott\u2019s Puffy T\u00fcm\u00f6r Geli\u015fimi. Turk Pediatri Ars.","DOI":"10.14744\/TurkPediatriArs.2020.28863"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/S0090-3019(01)00344-5","article-title":"Frontal Sinus Osteoma Associated with Cerebral Abscess Formation: A Case Report","volume":"55","author":"Summers","year":"2001","journal-title":"Surg. Neurol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"737","DOI":"10.4103\/ajns.AJNS_196_20","article-title":"Subdural Empyema Complicating a Giant Fronto-Ethmoidal Osteoma","volume":"15","author":"Benzagmout","year":"2020","journal-title":"Asian J. Neurosurg."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"e9376","DOI":"10.1097\/MD.0000000000009376","article-title":"Osteoma with Actinomycosis in a Nasal Cavity: A Case Report","volume":"96","author":"Kim","year":"2017","journal-title":"Medicine"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"48","DOI":"10.4103\/1817-1745.154340","article-title":"Giant Spheno-Ethmoidal Osteoma in a 14-Year Boy Presenting with Visual Impairment and Facial Deformity: Short Review","volume":"10","author":"Satyarthee","year":"2015","journal-title":"J. Pediatr. Neurosci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"e17","DOI":"10.1097\/SCS.0000000000003164","article-title":"Large Frontoorbital Osteoma Causing Ptosis","volume":"28","author":"Ata","year":"2017","journal-title":"J. Craniofac. Surg."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1429","DOI":"10.1007\/s00405-020-06420-x","article-title":"Gigantic Paranasal Sinuses Osteomas: Clinical Features, Management Considerations, and Long-Term Outcomes","volume":"278","author":"Giotakis","year":"2021","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"e622","DOI":"10.1097\/SCS.0000000000005649","article-title":"An Extremely Rare Cause of Headache; Osteoma of the Middle Concha Bullosa","volume":"30","author":"Gulsen","year":"2019","journal-title":"J. Craniofac. Surg."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"e745","DOI":"10.1097\/SCS.0000000000003895","article-title":"A Rare Cause of Headache: Pneumatized Nasal Septum Osteoma","volume":"28","author":"Ismi","year":"2017","journal-title":"J. Craniofac. Surg."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1007\/s12070-010-0083-8","article-title":"Inferior Turbinate Osteoma\u2014Rare Cause of Nasal Obstruction","volume":"62","author":"Kumar","year":"2010","journal-title":"Indian J. Otolaryngol. Head. Neck Surg."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"e471","DOI":"10.1097\/SCS.0000000000001122","article-title":"Endonasal Endoscopic Excision of a Rare Tumor: Nasal Bone Osteoid Osteoma","volume":"25","author":"Yazici","year":"2014","journal-title":"J. Craniofac. Surg."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"e17036","DOI":"10.1097\/MD.0000000000017036","article-title":"Peripheral Osteoma of the Nasal Bone after Laser Treatment: A Case Report","volume":"98","author":"Hwang","year":"2019","journal-title":"Medicine"},{"key":"ref_48","first-page":"39","article-title":"Osteoma of the Sphenoid Sinus","volume":"1","author":"Strek","year":"2005","journal-title":"B-ENT"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1016\/j.radcr.2020.04.046","article-title":"Report of 3 Cases of Pediatric Sinus Osteomas with Osteoblastoma-like Features","volume":"15","author":"Evans","year":"2020","journal-title":"Radiol. Case Rep."}],"container-title":["Clinics and Practice"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2039-7283\/16\/7\/126\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T10:37:27Z","timestamp":1783334247000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2039-7283\/16\/7\/126"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,4]]},"references-count":49,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["clinpract16070126"],"URL":"https:\/\/doi.org\/10.3390\/clinpract16070126","relation":{},"ISSN":["2039-7283"],"issn-type":[{"value":"2039-7283","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,4]]}}}