Glial choristoma of the middle ear: report of 2 cases

Neuroglial heterotopia of the middle ear: A case series and systematic literature review

Background

The differential diagnosis for mass forming lesions of the middle ear is broad. While uncommon, neuroglial heterotopias can occur in the middle ear and can be a source of diagnostic confusion for clinician, radiologist, and pathologist alike.

Methods

We identified three cases of neuroglial heterotopia of the middle ear in our institutional archives from 2000 to 2020 and performed extensive histological and immunohistochemical characterization of the three lesions. We conducted a systematic literature review to identify 27 cases published in the English literature between the years 1980 and 2020. Only cases with histological verification of neuroglial heterotopia specifically involving the middle ear were included. We compiled the clinical, radiological, and histopathological findings for all 30 cases.

Results

Patients most frequently presented with chronic otitis media (40%), hearing loss (40%), or prior history of ear surgery or trauma (13%). The median age at surgery was 49 years with a male predominance (M:F 2:1); however, a bimodal age distribution was noted with an earlier onset (11 years or younger) in a subset of patients. Immunohistochemical characterization showed mature neuronal and reactive glial populations with low Ki67 proliferation index and chronic inflammatory infiltrates. There was no neuronal dysplasia or glial atypia, consistent with benign, nonneoplastic, mature glioneuronal tissue.

Conclusion

Immunohistochemical characterization of these lesions and clinical follow-up confirms their benign natural history. Potential etiologies include developmental misplacement, trauma, and chronic inflammation/ reactive changes resulting in sequestered encephalocele.

Glial heterotopia of the middle ear

INTRODUCTION

Glial heterotopia is defined as the presence of normal glial tissue in an abnormal site.

CASE REPORT

We report the case of a 63-year-old man who presented with right hearing loss and tinnitus. ENT examination, computed tomography and magnetic resonance imaging showed signs of chronic otitis media. Right mastoidectomy demonstrated a solid mass of the right mastoid and middle ear with no associated dehiscence of the tegmen tympani. Histological examination of the mass revealed normal glial tissue.

DISCUSSION

Glial heterotopia is a rare entity, which must be distinguished from encephalocele. It is usually an incidental surgical finding when the surgeon observes a mass of the mastoid and middle ear not communicating with the central nervous system. Histological examination confirms the diagnosis by revealing normal glial tissue in the ear.

Diagnosis and treatment of the pharyngeal glial choristoma accompanied with incomplete cleft palate: A case report

INTRODUCTION

A choristoma formed by heterotopic tissue rarely occurs in the throat, especially one accompanied with cleft palate in a new-born baby.

PATIENT CONCERNS

An 18-month-old female patient was admitted to the hospital for apparent snoring symptoms accompanied by mouth breathing and sleep apnea. In addition, the patient presented with weak aspiration and nasal leakage during fluid intake.

DIAGNOSIS

The patient received routine physical examination and endoscopy showing that there was a wide fissure which split from the palate vertical anterior cleft to 1/3 of the hard palate. Meanwhile, we found an unclear-bordered uplift in the left palate and a soft mass. The radiographs revealed a mass with inhomogeneous density convex to the pharyngeal cavity.

INTERVENTIONS

The patient was subsequently referred for surgical resection and tissue diagnosis of choristoma was confirmed by pathological examination. H&E staining showed well demarcated mature brain tissue with scattered sand-like calcification.

OUTCOMES

According to the diagnosis, the patient suffered from pharyngeal glial choristoma and incomplete cleft palate. The surgical resection and repair were performed together. The postoperative recovery was very good.

LESSONS

Choristoma rarely occurs in the head and neck, especially if accompanied by cleft palate. Early diagnosis for choristoma relies heavily on clinical examination and radiological imaging. Complete resection of choristoma remains the gold standard for treatment of these patients.

Neuroglial Choristoma of the Middle Ear with Massive Tympanosclerosis: A Case Report and Literature Review

Neuroglialchoristoma is a rare cerebral heterotopia typically involving extracranial midline structures of the head and neck, including the nose, nasopharynx and oral cavity. It rarely involves non-midline structures, such as the middle ear, mastoid and orbit. We report the case of a 63-year-old woman with right-sided hearing loss and aural fullness who was diagnosed with neuroglialchoristoma of the middle ear and mastoid. To our knowledge, this is the first report on neuroglialchoristomawith massive tympanosclerosis. The presence of combination supported the inhalation theory of neuroglialchoristoma, given that tympanosclerosis is typically caused by Eustachian tube dysfunction.