Related Experiment Video
Updated: Aug 26, 2025

Single-stage Dynamic Reanimation of the Smile in Irreversible Facial Paralysis by Free Functional Muscle Transfer
Published on: March 1, 2015
Cholesterol granuloma in facial nerve canal presenting with facial nerve paralysis
Naoyuki Matsumoto1, Akinori Kashio2, Masafumi Yoshida3
1Department of Otorhinolaryngology and Head and Neck Surgery, Kameda Medical Center, Kamogawa-shi, Chiba, Japan; Department of Otolaryngology and Head and Neck Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Abstract:
Cholesterol granulomas (CGs) are frequently found in the temporal bone, but their presence in the facial nerve has not been reported. We report a case of a 58-year-old woman who presented with left facial palsy caused by a CG that appeared to have originated in the facial nerve. Temporal bone computed tomography (CT) revealed soft tissue masses in the left middle ear spaces, and the facial canal was dilated from the genu to the vertical portion. Magnetic resonance imaging (MRI) revealed high signal intensity on T1-weighted images and partially high signal intensity on T2-weighted images, although no significant enhancement was observed on gadolinium-enhanced MRI. Surgical findings revealed CG in the middle ear spaces, but the facial canal remained intact and lacked continuity with the internal mass. Histopathological analysis verified the mass as a CG accompanied by cholesterol crystals. The mass was located within and continuous with the epineurium. These findings indicate that hemorrhage in the facial canal may have triggered the formation of the CG, causing left facial palsy due to increased pressure in the facial canal.
Related Concept Videos
Cranial Part of Parasympathetic Division
The vagus nerve (cranial nerve X) alone accounts for approximately 75...
Cranial Nerves: Types Part II
Facial Nerve (Cranial Nerve VII)
Cranial nerve VII, or the facial nerve,...
Myasthenia Gravis: Overview and Treatment
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which...
Cranial Nerves: Types Part I
Olfactory Nerve (Cranial Nerve I)
The olfactory nerve, or cranial nerve I, is unique as it is purely sensory and dedicated to the sense of smell. This nerve originates in the olfactory epithelium of the...
Myasthenia Gravis: Diagnostic Tests
The edrophonium test is a diagnostic tool for myasthenia gravis. It involves...
Peripheral Nervous System: Ganglia and Nerves
Nerves
The nerve is a bundle of axons that serves as the communication highway in the PNS. Each nerve is ensheathed in a protective layer of connective tissue called the epineurium. This outermost layer safeguards the nerve and supports the...

