Safety of Carotid Canal during Transtympanic Dilatation of the Eustachian Tube: A Cadaver Pilot Study.

To assess the safety of Transtympanic balloon dilatation of the cartilaginous proximal Eustachian tube under endoscopic guidance as it relates to the integrity of the carotid canal in cadaver model. Endoscopic guided Transtympanic dilatations of the cartilaginous proximal end of the Eustachian tube were performed in 15 ears of 8 fresh frozen cadaver heads. CT scans were done before and after dilatation. Images were reviewed by two otologists and one radiologist. Balloon catheter placement and dilatation of the proximal Eustachian tube was feasible in all specimens. Endoscopic examination post dilatation showed a consistent increase in the aperture of the proximal cartilaginous tube in all ears. Review of CT images after dilatation showed no evidence of trauma to the carotid canal in all ears instrumented. Endoscopically guided Transtympanic dilatation of the proximal Eustachian tube is not associated with damage to the carotid canal in cadaver model. Level of Evidence: 4.

Endoscopic cochlear implantation: Call for caution.

OBJECTIVES/HYPOTHESIS: To assess whether transcanal endoscopic access to the basal turn of the cochlea for cochlear implantation is appropriate. STUDY DESIGN: Case series study. METHODS: We reviewed 100 consecutive computed tomographic studies of the sinuses and temporal bone in our institution. We excluded studies that demonstrated evidence of congenital anomalies, chronic ear disease, or inadequate visualization of the cochlea. On axial sections, the angles of the basal turn of the cochlea and of the ear canal in reference to the sagittal plane were recorded as a function of age. RESULTS: Eighty-four studies were included and 16 were excluded. There was significant variability in the relationship between the ear canal and the basal turn of the cochlea in reference to the sagittal plane. A clear majority of images demonstrated the basal turn of the cochlea to align with a more posterior angle than that of the ear canal. CONCLUSION: The trajectory provided by posterior tympanotomy aligns more favorably with the basal turn of the cochlea than transcanal access. Endoscopic technique, primarily an ear canal intervention, may not be useful in cochlear implant surgery. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:689-692, 2016.

Site of eustachian tube obstruction in chronic ear disease.

OBJECTIVE: Assess the patency of the proximal and distal segments of the Eustachian tube in patients undergoing surgery for chronic ear disease. STUDY DESIGN: Case study with control group. METHODS: All consecutive patients presenting for surgery for chronic ear disease in our practice over 14 months underwent preoperative Valsalva computed tomography (CT), and an attempt was made intraoperatively using angled rigid scopes to evaluate obstruction of the protympanic segment of the Eustachian tube. Endoscopic examination of the same segment in 19 cadaver ears served as a control group. RESULTS: Preoperative Valsalva CT showed patency of the distal one-third of the Eustachian tube in 51 of 53 ears. Intraoperative endoscopy allowed visualization of the protympanic opening of the Eustachian tube in 31 of 53 ears; 21 of 31 ears showed obstruction of the protympanic opening of the Eustachian tube. CONCLUSION: A clear obstruction was more likely to be present in the protympanic opening of the Eustachian tube in the patient population undergoing surgery for chronic ear disease than in the cadaver control group, and was equally likely to be present in the distal cartilaginous tube in patients as in the control population. LEVEL OF EVIDENCE: 4.

Transtympanic dilatation of the eustachian tube during chronic ear surgery.

CONCLUSION: Evaluation of the protympanic segment of the eustachian tube is feasible during chronic ear surgery. Balloon dilatation of that segment yields a bigger aperture. OBJECTIVE: To evaluate the feasibility of visualization and balloon dilatation of the protympanic segment of the eustachian tube during chronic ear surgery. METHODS: This study was carried out on a consecutive case series. All patients undergoing surgical treatment for cholesteatoma or tympanic membrane perforation over a 6-month period of time at a tertiary hospital were evaluated intraoperatively for the ability to visualize the protympanic segment of the eustachian tube, perform balloon dilatation, and then perform visual inspection of the effect of dilatation. RESULTS: A total of 21 chronic ear procedures were performed; visualization of the protympanic segment was feasible in 12 ears, obstruction was identified in 7 ears, and dilatation was undertaken. Immediate assessment showed increased aperture of the tube in all patients when compared with predilatation findings.

Visualization of the eustachian tube lumen with Valsalva computed tomography.

OBJECTIVES/HYPOTHESIS: Assess the feasibility of using the Valsalva maneuver to visualize the cartilaginous eustachian tube lumen with computed tomography (CT) in subjects with no ear disease. STUDY DESIGN: Prospective case series study. METHODS: Thirty-eight consecutive patients undergoing CT of the sinuses for nose-related complaints with normal radiographic findings consented for a CT of the temporal bone while performing the Valsalva maneuver. Multiplanar reconstruction was performed along the axis of the tube. Images were assessed for visualization of the whole length of lumen of the tube, or partial visualization with ratio of visualized to nonvisualized segments. RESULTS: The Valsalva maneuver allowed visualization of the whole length of the tube in 27/76 (35%) ears examined. It consistently visualized the distal one-third of the cartilaginous tube in 71/76 (94%) ears. Paradoxical collapse of the eustachian tube was present in three ears along with evidence of poor Valsalva technique. CONCLUSIONS: Valsalva CT consistently allows visualization of the lumen of the distal one-third of the eustachian tube in a majority of patients with no eustachian tube-related complaints. This technique might be helpful in localizing eustachian tube pathology in patients with obstructive tube symptoms.