Fistula of Stapes Footplate Caused by Pulsatile Cerebrospinal Fluid in Inner Ear Malformation

Abstract

Congenital malformations of the inner ear are well described, though the combination with cerebrospinal fluid (CSF) leaks remains controversial. In this paper a case of a bilateral Mondini malformation with a CSF otorrhea on one side is reported. The malformed stapes contains a perforation in the middle of the footplate and associated thinning analogous to a pothole in a mountain stream. The histological findings support the hypothesis of pulsatile flow of CSF as origin of the perforation of the footplate.

Lateral petrosectomy with obliteration cavity for spontaneous cerebrospinal otorrhea in children

“…The most common causes of CSF leak are mechanical or postoperative injuries, infections or congenital malformations of the inner ear [1, [3][4][5]10]. Most CSF leaks close spontaneously with conservative treatment; some require surgical treatment [5,8,9,11]. In the study conducted by Savva et al, 32% of the patients with CSF leak had a history of head trauma, 58% were operated in the head region and in 11% otorrhea was spontaneous [5].…”

“…In the study conducted by Savva et al, 32% of the patients with CSF leak had a history of head trauma, 58% were operated in the head region and in 11% otorrhea was spontaneous [5]. Spontaneous otorrhea in adults is usually caused by dural herniation through defects of the tympanic cavity walls [4,8,9]. According to Hoppe et al [11] over 20 % of the patients with sensorineural hearing loss present a congenital malformation of the temporal bones on CT.…”

“…Repeated lumbar drainage has been used in an attempt to lower intracranial pressure and remove CSF at a rate equal to its production. A variety of possible surgical approaches exist, including tympanotomy, middle fossa, retrosigmoidal or translabyrinthal [4,7,9]. In order to perform obliteration of the fistula together with the tympanic cavity in case of CSF leak to the middle ear, it is advisable to choose a combination of at least two different components, choosing from fat, muscle tissue, fragments of cartilage, bone or a piece of fascia with tissue adhesive [4,7].…”

Imaging of Cerebrospinal Fluid Leaks*

“…The communication usually passes either along the vestibulocochlear nerve, from the internal auditory meatus, or from a dilated vestibular aqueduct [40] into a dysplastic labyrinth. A stapes deformity, congenital or due to erosion from CSF pulsations, frequently allows fluid leakage ("stapes gusher") into the middle ear ( Figure 10).…”

Cerebrospinal Fluid Leaks of Temporal Bone Origin: Etiology and Management

“…Congenital leaks are due to labyrinthine or perilabyrinthine dysplasia, or are related to anomalies located distant from the otic capsule. The most common labyrinthine abnormality is Mondini dysplasia [7] . Malformations like patent retromastoid canal, enlarged and patent cochlear aqueduct, patent Hyrtl's fi ssure, enlarged facial nerve canal or dehiscent lamina cribrosa of the inner auditory canal are the known perilabyrinthine pathologies.…”