Objective Assessment of Temporal Bone Drilling Skills

Objectives:

There is great interest in training surgeons in the technical aspects of their craft through simulation and laboratory-based exercises. However, there are as yet only a few objective tools to assess technical performance in a laboratory setting. This study assesses three potential objective assessment tools for a traditional otolaryngology laboratory exercise, temporal bone drilling.

Methods:

We performed a validation study in an academic training program. Nineteen otolaryngology residents performed a cortical mastoidectomy on a cadaveric temporal bone. The participants were divided into two groups, experienced and novice, based on previous temporal bone drilling experience. Performance was rated by two independent, blinded experts using four different assessments, the Global Rating Scale (GRS), the Task-Based Checklist (TBC), the final product analysis (FPA), and expert opinion (EO).

Results:

The interrater reliability for all four assessments was good. Two potential objective assessments, the GRS and the TBC, and the traditional assessment tool of EO, correlated with trainee experience. The FPA, however, did not correlate with trainee experience. A logistic regression analysis of all assessments showed that the TBC correlates with EO.

Conclusions:

This study validates EO, the GRS, and the TBC as measures of temporal bone drilling performance. Of these measures, the TBC correlates best with EO according to logistic regression and can be reliably used as an objective assessment of temporal bone drilling.

Transmastoid partial labyrinthectomy for brainstem vascular lesions: clinical outcomes and assessment of postoperative cochleovestibular function

OBJECTIVES

To discuss the transmastoid partial labyrinthectomy approach for brainstem vascular lesions, with respect to hearing and balance preservation.

DESIGN

Retrospective case series.

SETTING

Tertiary referral center (University Health Network, Toronto).

PARTICIPANTS

Nine consecutive surgical patients between 1999 and 2004.

MAIN OUTCOME MEASURES

Clinical, audiometric, and electrophysiological vestibular data.

RESULTS

Nine transmastoid partial labyrinthectomy procedures (all females) were performed. In seven patients the underlying pathology was an intra-axial brainstem cavernous malformation. Two patients were treated for a basilar artery aneurysm. All patients had progressive neurological signs. Serviceable hearing (pure tone average (PTA): < 50 dB; speech discrimination score (SDS): > 50%) was preserved in seven patients. Partial vestibular function (clinical and electrophysiological) was maintained in most patients.

CONCLUSIONS

The partial labyrinthectomy approach to the skull base provides excellent exposure while preserving cochleovestibular function in most patients.