Otology & Neurotology 00:00Y00 Ó 2015, Otology & Neurotology, Inc.

Imaging Case of the Month

Persistent Tubotympanic Recess With Eustachian Tube Atresia *Aisha Larem, *Rashid Sheikh, *†Abdulsalam Alqahtani, *Sara Ashkanani, and *Hassan Haidar *Otolaryngology Department, Rumailah Hospital, Hamad Medical Corporation; and ÞWeill Cornell Medical College in Qatar, Doha, Qatar

The Eustachian tube (ET) is derived from the first branchial pouch, which extends laterally between the first and second branchial arches to form the tubotympanic recess (TTR). The distal part of the TTR becomes the primitive tympanic cavity, and the proximal part constricts to form the lumen of the fibrocartilaginous ET. These phenomena occur between 4 and 6 weeks of gestation (1). By the 14th week of gestation, the tubal cartilage and tensor tympani muscle develop from the mesenchyme surrounding the TTR that is populated with migratory neural crest cells (2). Very few ET anomalies have been published in the literature and have primarily consisted of descriptions of diverticula, hypoplasia/aplasia, fistula, or aberrant paratubal musculature (3). We report a unique case of bilateral persistent TTR associated with bilateral fibrocartilaginous ET atresia in a patient with tetralogy of Fallot (TOF). To our knowledge, this anatomic aberration has not been previously reported.

Audiometry revealed bilateral mild conductive hearing loss. Temporal bone computed tomography showed bilateral significant widening of the presumed ET, which ended as cul de sacs near the sphenoid sinuses. The cartilaginous ET and tensor tympani muscle canals were absent on both sides (Fig. 1). Nasopharyngeal endoscopy confirmed the absent ET orifices bilaterally. Left tympanoplasty was performed, and intraoperative endoscopy revealed a wide bony protympanum that ended as a cul de sac (Fig. 2). Follow-up after 6 months showed an intact graft with near normal left ear hearing and tympanic membrane compliance. This case report was granted ethical approval and permission for publication from the medical research center of Hamad Medical Corporation of Qatar with the reference number MRC/511/2014. DISCUSSION

CASE

ET anomalies are associated with cardiac anomalies. Neural crest cells are involved in the differentiation of branchial arches, including the precursor tissues of the cardiac outflow tract and ETs (4). Our patient had bilateral ET malformations and TOF. We can assume that the embryonic TTR, after initial evagination from the pharynx, could have been interrupted at the nasopharynx by misdevelopment of the surrounding defective mesenchyme. In addition, failure of the development of tubal cartilage and tensor tympani muscle could be associated with a persistently wide TTR. We attribute this malformation to a field defect arising from neural crest cells that affected the ETs and the cardiac outflow tract, leading to bilateral ET malformation in association with TOF. In this case, computed tomography and endoscopic views clearly demonstrated that there was no connection between the middle ear and nasopharynx. Bidirectional

An 18-year-old female patient, with a status of postcorrective repair of TOF, presented with a long-standing history of bilateral recurrent otorrhea. On examination, the left ear had a dry central perforation, whereas the right ear had an atrophic cicatricial tympanic membrane. Address correspondence and reprint requests to Dr. Hassan Haidar, Otolaryngology Department, Hamad Medical Corporation, Doha, Qatar; E-mail: [email protected] Author Contributions: Concept V H. H. and A. L.; Design V H. H. and R. S.; Supervision V A. Q.; Data Collection and/or Processing V R.S. and S.A.; Analysis and/or Interpretation V H. H. and A.L.; Literature Review V S.A., R.S.; Writing V H. H. and R. S.; Critical Review V A. Q. and H. H. Conflict of Interest: The authors disclose no conflicts of interest. Informed Consent: Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

1

Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.

2

A. LAREM ET AL.

FIG. 1. Temporal bone computed tomography scan transverse cuts (right ear [A] and left ear [B]) and multiplanar reconstruction in the plane of the Eustachian tube (right ear [C] and left ear [D]) showing bilateral persistent TTR (T) ending as blind cul de sacs near the sphenoid sinus (S) and absence of opening into the nasopharynx (N). C: horizontal canal of petrous carotid artery.

FIG. 2. A, Nasopharyngoscopy showing the presence of small adenoid vegetation (A) and absence of Torus tubaris on both sides. B, Left middle ear intraoperative endoscopy using a 30-degree scope showing significant widening of the protympanum that continues as a persistent TTR (T) with a blind end. P: promontory.

gas exchange throughout the middle ear mucosa could explain the aeration of the middle ear after closure of the tympanic membrane.

University Libre de Bruxelles, Professor Patrick Louryan, for his great contribution in the developmental explanation of this case.

CONCLUSION REFERENCES We present a unique case of chronic otitis media with a developmental anomaly of the branchial archesVa bilateral persistent TTR with fibrocartilaginous ET atresia and TOF. Tympanoplasty was successful in this case. This is the first case of persistent TTR with fibrocartilaginous ET atresia in the literature. Acknowledgment: We would like to thank the Chairman of the Anatomy, Biomechanics, and Organogenesis Laboratory of

1. Cummings CW, Frederickson JM, Harker LA, et al. Anatomy and Physiology of the Eustachian Tube. Otolaryngologyy Head and Neck Surgery. St. Louis, MO: C.V. Mosby Co., 1986. 2. Swarts JD, Rood SR, Doyle WJ. Fetal development of the auditory tube and paratubal musculature. Cleft Palate J 1986;23:289Y311. 3. Hoesli RC, Johnson J, Meyer A, Green G. Eustachian tube duplication: a unique anomaly. Otol Neurotol 2014;35:1099Y101. 4. Todd JL, Todd NW. Conotruncal cardiac anomalies and otitis media. J Pediatr 1997;131:215Y9.

Otology & Neurotology, Vol. 00, No. 00, 2015

Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.

Persistent Tubotympanic Recess With Eustachian Tube Atresia.

Persistent Tubotympanic Recess With Eustachian Tube Atresia. - PDF Download Free
1MB Sizes 4 Downloads 17 Views