Congenital cholesteatoma is a very rare disease; however it could be expected in the presence of congenital anomalies of the external ear, however it is more frequent in cases of EAC stenosis rather than in cases of complete atresia [3]. Levenson et al. [5] have suggested strict criteria for diagnosis of CC which are a whitish mass present in the middle ear cavity with normal tympanic membrane, the pars flaccida and pars tensa of tympanic membrane showed normal findings, no history of otorrhea or perforation, no history of otological surgery, history of otitid media is not an exclusion for the disease, and intramembranous cholesteatoma or giant cholesteatoma may be encountered in cases with CAA. According to the last criterion, our case has a giant temporal bone congenital cholesteatoma. In 2006, Caughey et al [6] have reported a case of CAA with congenital cholesteatoma medial to the atretic plate, with no ossicular erosion. The authors have removed the malleus-incus complex to facilitate complete removal of cholesteatoma and the conductive hearing mechanism was reconstructed using partial ossicular replacement prosthesis. However, our case showed no malleus-incus complex that raises the suggestion of its erosion by cholesteatoma and then we placed the temporalis fascia on the head of the stapes for hearing reconstruction and we succeeded to narrow the air-bone gap from 60 to 35 dB.
Regarding the site of occurrence of CC, it is usually located intradurally; less frequently (20%), an extradural location is noted. There are five general sites of extradural occurrence: the middle ear, external auditory meatus, the mastoid, squamous portion of temporal bone and the petrous apex [1]. In 2010, Chen et al [7] have reported the first case of CC of the infratemporal fossa in a five year-old child who has presented with middle ear effusion with a whitish mass behind the antero-inferior quadrant of the tympanic membrane. Computed tomography and magnetic resonance imaging has showed that the mass was present in the hypotympanum and infratemporal fossa. They concluded that the infratemporal fossa is the site of origin with limited extension to the hypotympanum; depending on the main bulk of the mass was detected in the infratemporal fossa radiologically and on intra-operative finding. However in our case, the mass was detected in the antero-inferior part of the hypotympanum medial to the atretic plate with erosion of the middle ear floor antero-inferiorly and extension of cholesteatoma mass to the infratemporal fossa. The primary site of origin of CC –in our opinion- may be the antero-inferior part of the middle ear space, as it is logic to suggest that entrapment of epithelial cell rests behind the atretic plate resulting in formation of cholesteatom that consequently eroded the bone and expanded freely within the soft tissues of the infratemporal fossa, this may explain the presence of the largest part of the mass in the infratemporal fossa rather than in the temporal bone as expansion within yielding tissues is more easier than expansion within the bone. An exposed intact fibrous capsule of the tempromandibular joint through a small bony defect was detected intra-operatively, it needed no intervention as the capsule was not herniated even with passive movement of the joint.
Acute mastoiditis has been reported to be the first presentation of CC in a normally developed ear; Hidaka et al [2] has reported a case of CC of mastoid region in a sixty five-year-old man that presented with acute mastoiditis as the first presentation.
Also, CAA may be presented with acute mastoiditis; Zalzal [8] has published a case of CAA that was presented with acute mastioditis and lateral sinus thrombosis in a two-year-old boy.
Pawełczyk and Czarski [9] published a case of CC of the middle ear in a twelve-year old child with CAA complicated by mastoid abscess. To the best of our knowledge, our case is the second case of CC with CAA to present with acute mastoiditis after the case of Pawełczyk and Czarski [9] and it is the first case to be presented with CC extended to the infratemporal fossa with the presence of CAA and mastoiditis.