CI Atlas · Preoperative Imaging · Module 18

18The structured preoperative report

Everything in this chapter exists to be written down in one place, for one ear at a time, so that nothing surgical is missed. A structured, side-specific report walks the same path the surgeon will: the mastoid and its vessels, the facial nerve, the cochlear turns and modiolus, the patency and duct length, the malformations and the vestibular aqueduct, and — from the MRI — the calibre of the cochlear nerve. But a list of findings is not yet useful; the report has to end with an actionable summary that names the implantable side, the hazards to expect, the array to order and whether the patient should have a cochlear implant at all. That summary closes the loop back to candidacy and forward to surgery, devices and objective measures. This closing module is the report.

Imaging note

Representative CT and MRI images for this chapter are being added soon. The interactive figures here are original schematic teaching diagrams; to respect copyright we do not reproduce third-party radiographs.

TWhy a structured report

The report is side-specific (right/left) and structured so nothing surgical is missed — the chapter's whole purpose distils into this checklist, and it explicitly answers the three framing questions of Module 2.[2022]

The whole chapter distils into a structured, side-specific report so nothing surgical is missed. The HRCT checklist runs from mastoid pneumatisation, ossicles and the facial nerve to the cochlear turns, modiolus, aperture, patency, duct length and any malformation; the MRI checklist adds cochlear-nerve calibre and the CP angle. Crucially, a good report ends with an actionable summary: the implantable side, predicted intra-operative hazards (gusher, aberrant facial nerve, ossification drill-out), the recommended array, and any need for intra-operative confirmation — closing the loop to Candidacy, Surgery, Devices and Objective Measures. Schematic.

CThe HRCT checklist

The HRCTitems run from skull thickness, mastoid pneumatisation, otic capsule, Korner's septum, middle-ear aeration and ossicles, through the facial nerve (anomalous/dehiscent), sigmoid sinus, tegmen, jugular bulb and internal carotid artery, to the cochlear items: turns, modiolus, cochlear aperture (BCNC), interscalar septa, patency, lamina cribrosa, orientation, cochlear duct length and any malformation — plus the vestibule, canals, vestibular and cochlear aqueducts (EVA) and the IAC dimensions.

CThe MRI checklist

The MRI checklist adds the cochlear-nerve calibre (oblique-sagittal), the endolymphatic duct/sac, the CP angle, the brainstem and brain, and previous-surgery status. The Eisenhut image-quality grading doubles as a structured reporting scaffold with or without an implant in place.

TThe actionable summary

A good report ends with an actionable summary: the implantable side, the predicted intra-operative hazards (gusher, aberrant facial nerve, ossification drill-out), the recommended array, and any need for intra-operative or fluoroscopic confirmation — with an ABI flag where the cochlea or nerve is absent. That single paragraph closes the loop to Candidacy, Surgery, Devices and Objective Measures — the scan turned into a plan.

Case 12.18 · What the report must conclude

A radiologist completes a detailed preoperative scan review and writes a long list of findings.