14A Prognosis-Oriented Algorithm for Decision-Making
Anatomy classifications name the deformity but stop short of telling you what to do. This chapter's centrepiece is a prognosis-oriented algorithm - the author's own research - that drives from hearing status and imaging through eight questions to a treatment, a surgical-difficulty forecast and a prognosis.
FWhy a new algorithm
The seminal classifications - Jackler (embryogenesis), Sennaroglu (the most widely accepted scheme worldwide) and Grover/SMS (cochlear, modiolar and lamina-cribrosa morphology) - describe anatomy but overlap, and intermediate forms exist. Crucially, these schemes do not incorporate the cochlear nerve and the bony cochlear-nerve canal (BCNC) - the very factors that determine CI candidacy and outcome. They therefore do not, by themselves, support accurate treatment planning, prediction of complications, or prognosis. The author's algorithm takes the best of the existing schemes and reorganises them around decision-making.[2024][1987][2002][2019]
TThe eight questions
The flow runs as a stepwise decision tree driven by hearing status plus imaging: (1) Type of hearing loss? conductive vs severe-to-profound SNHL. (2) Useful cochlear lumen present? (3) Cochlear aperture and nerve normal? (4) Type of inner-ear anomaly? (5) Facial-nerve anomaly present? (6) Potential gusher? The final questions reach the verdict: (7) Candidate for CI or ABI? and (8) Suitable CI electrode? Each branch yields not only a treatment but an anticipated surgical difficulty (facial-nerve aberrancy, gusher) and a prognosis. The same six clinical inputs are asked of every patient, so the algorithm is reproducible across a multidisciplinary team rather than dependent on one expert's gestalt.[2024][2017]
CReading the decision map
Conductive loss + useful lumen + normal aperture/nerve (e.g. cochlear hypoplasia type II/III presenting conductively) -> stapedotomy or hearing aid, not an implant. Severe-to-profound SNHL + useful lumen + normal aperture/nerve -> cochlear implant, with the anomaly predicting gusher: EVA always oozes (pulsatile), IP-II gushers in under 10%, IP-III gushers in 100%, common cavity rarely, and cochlear hypoplasia II/III/IV possible (especially CH-II); facial-nerve anomaly is flagged in IP-III, common cavity and hypoplasia. When the nerve is the problem: cochlear nerve hypoplasia with only cochlear-aperture anomalies can still go to CI, whereas cochlear nerve aplasia goes to ABI. No useful lumen / nerve absent - common cavity, cochlear hypoplasia II/III/IV, cochleovestibular aplasia, rudimentary otocyst, cochlear aplasia, IP-I and CH-I -> ABI; IP-I additionally carries a ~50% gusher rate.[2024][2016][2005]
FWhat the algorithm buys you
Stated benefits: it is simple, avoids the overlap of anatomy-only schemes, and eases understanding of the different IEMs. It facilitates optimal treatment planning and anticipates surgical difficulties and complications (gusher, facial-nerve aberrancy) before incision. It aids in predicting prognosis and outcomes, so counselling is grounded in the child's specific branch. It assists communication among teammates and is a teaching aid for junior colleagues and residents - a shared, reproducible language for IEM decisions.[2024]
Stepping through the prognosis-oriented algorithm, what does this child's branch predict?
What do the Jackler, Sennaroglu and Grover/SMS classifications omit that the author's algorithm explicitly routes on?
In the algorithm, which incomplete-partition type carries a 100% expected gusher rate?
A child with severe-to-profound SNHL has no useful cochlear lumen and an absent cochlear nerve. Which destination does the algorithm give?