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Paediatric canal wall down mastoidectomy (CWDM) has a reputation for large with cavities 30–44% discharging at times [1, 2, 3]. A 90% dry ear rate is achievable [4, 5]. The factors most likely to produce a dry ear after CWDM are: small cavity, low facial ridge, sealing the mesotympanum and a meatoplasty tailored to cavity size [6]. Cavity size can be minimised by following the disease from the tympanum, superiorly and posteriorly, to its limit [7]. Toner and Smyth [8] reported excellent results using this approach. The senior author prefers small cavity mastoidectomy for management for cholesteatoma/retraction pocket disease (Fig. 1).

The senior author's personal surgical database was reviewed for cases of cholesteatoma or discharging retraction pocket in children under sixteen years of age. Demographic data, dry ear rate and hearing at one year were recorded. An ear was considered dry if there was one infection or less per annum.

Of 50 children identified, 5 were lost to follow up within 6 months of surgery. Forty-four were examined at 1 year, 32 at 2 years and 20 at 3 years. The age, sex and surgery performed are shown in Table 1. Table 2 gives the dry ear rate. Forty-one children had hearing results available at 1 year and Table 3 shows the postoperative air bone gap presented in 10 dB bins.

Three patients had postoperative aural discharge. One because of air cells at the sinodural angle, one due to attic granulation tissue and one due to scarring in the 'attic' region of the cavity creating a new pocket with retained infection. Technical failure was attributable to cholesterol granuloma in two cases, dry perforation in two cases, myringitis in one case and small cavity pearls in one case.

The philosophy of small cavity mastoidectomy prefers CWD surgery with its better access to the sinus tympani, facial recess and oval window niche ICWM. Cavity size is limited by dissecting from the pocket neck to the extent of the disease. In this way, shallow retraction pockets and small cholesteatomas can be excised without resort to large cavity creation. When the bony defect is limited to atticotomy, this can be sealed with a cartilage graft, the initial open approach providing confidence of disease removal. Large mastoid defects can be reduced by removal of the mastoid tip and shelving of the temporal bone, the adjacent soft tissues collapsing to produce a cavity.

The results shown confirm that this approach produces an acceptable dry ear rate following surgery and that in selected cases good hearing is achievable.