The Fungal Footprint: Radiologic Spectrum in Pulmonary, Paranasal Sinus and CNS Infections

Fungal infections can involve multiple organ systems, with imaging playing a pivotal role in their diagnosis and management. Fungal infections of Paranasal Sinuses (PNS) can be classified into invasive and non-invasive forms. Invasive fungal infections can be further divided into acute, chronic, or chronic granulomatous entities. It mainly affects immunocompromised patients with uncontrolled diabetes mellitus, Human Immunodeficiency Virus (HIV), and those on chemotherapy or chronic oral corticosteroids. Computed tomography remains the gold standard for sinonasal imaging while Magnetic Resonance Imaging (MRI) excels in assessing intraorbital and intracranial extensions. It is important to know and identify the characteristic imaging patterns of invasive and noninvasive fungal rhinosinusitis, and the radiologist is very important in refining the diagnosis to prevent a possible fatal outcome. This case series highlights the radiologic manifestations of fungal infections affecting the pulmonary system, Central Nervous System (CNS), and peripheral nervous system with characteristic imaging features ranging from invasive aspergillosis and mucormycosis to allergic fungal disease and rhinosporidiosis. Imaging findings includes sinus opacification, bony erosion, cavernous sinus invasion, orbital involvement, and cavitary lung lesions with Monod sign, ground-glass opacities and hyperdense mucus played a crucial role in diagnosis. By presenting a range of cases, this series aims to provide a comprehensive understanding of the imaging features associated with these infections, facilitating accurate diagnosis and treatment planning for radiologists and clinicians.