Imaging Spectrum Of Fungal Rhinosinusitis: An Updated Systematic Review And Narrative Synthesis Of CT And MRI Findings

Manjunatha YC; Sindhura S; Chandrakala S; Santosh D Patil

doi:10.37022/wjcmpr.v8i3.432

Authors

Manjunatha YC Department of Radiodiagnosis, Sri Devaraj Urs Medical College, Tamaka, Kolar, Karnataka, India
Sindhura S Department of Otolaryngology & Head Neck Surgery, East Point College of Medical Sciences & Research Centre, Bengaluru, Karnataka, India
Chandrakala S Department of Otolaryngology & Head Neck Surgery, East Point College of Medical Sciences & Research Centre, Bengaluru, Karnataka, India
Santosh D Patil Department of Radiodiagnosis, Jawaharlal Nehru Medical College, KLE University, Belgaum, Karnataka, India

Abstract

Background: Fungal rhinosinusitis (FRS) includes invasive and non-invasive disorders with distinct prognoses and management. Imaging is essential for assessing disease extent, tissue invasion, and orbital or intracranial complications and for distinguishing fungal ball and allergic fungal rhinosinusitis (AFRS) from invasive disease.

Objective: To synthesize CT and MRI features of major FRS subtypes, emphasizing imaging markers of invasion, extra-sinonasal spread, modality-specific strengths and limitations, and newer quantitative CT/MRI findings.

Methods: An evidence synthesis used the author-provided pictorial review as the framework and an updated PubMed search through 19 September 2026. The 2024 systematic review by Chen et al., encompassing 48 studies identified through searches of PubMed/MEDLINE, Embase, CENTRAL, and ScienceDirect through May 2023, served as the principal benchmark. Relevant post-May 2023 imaging studies were additionally incorporated. Given heterogeneous study designs, populations, reference standards, and imaging protocols, findings were synthesized narratively.

Results: CT best depicts sinonasal opacification, hyperattenuating fungal material, calcification, bone remodeling, and erosion, whereas MRI better characterizes soft-tissue devitalization and extra-sinonasal extension. Invasive disease commonly demonstrates bone erosion, perisinus fat infiltration, nasal cavity abnormalities, non-enhancing mucosa/turbinates, T2-hypointense fungal material, orbital involvement, and intracranial extension. The black turbinate sign is useful in context but not pathognomonic. Fungal ball typically shows focal hyperattenuation, calcification, and marked T2 hypointensity. AFRS demonstrates hyperattenuating allergic mucin, sinus expansion/remodeling, and characteristic MRI signal changes. Quantitative CT attenuation may help distinguish fungal ball from allergic fungal mucin, while pediatric studies highlight clinically relevant false-negative CT examinations.

Conclusion: Imaging findings should be interpreted as patterns. CT is the primary anatomic modality; contrast-enhanced MRI is recommended when invasive, orbital, skull-base, vascular, or intracranial disease is suspected. Persistent clinical concern warrants endoscopic evaluation and biopsy despite equivocal imaging.

Keywords:

Fungal Rhinosinusitis, Acute Invasive Fungal Rhinosinusitis, Allergic Fungal Rhinosinusitis, Fungus Ball, Computed Tomography, Magnetic Resonance Imaging

DOI

https://doi.org/10.37022/wjcmpr.v8i3.432

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