Tympanometry was analysed according to cleft type with respect to age in 23
9 cleft palate patients (57 with bilateral cleft lip and palate (BCLP)), 12
2 with unilateral cleft lip and palate (UCLP) and 60 with isolated deft pal
ate (ICP)). The frequency of type B tympanograms was 46.5 per cent in the B
CLP group, 50.6 per cent in the UCLP group and 58.3 per cent in the ICP gro
up. Type A tympanograms were more frequently observed in older patients (me
dian age 11 years) in comparison to type B (median age five years; p <0.001
) and type C (median age six years; p <0.001). The total sample showed an a
ge-related decrease in the frequency of type B tympanograms (r(s) = -0.3942
; p <0.001). The frequency of type A tympanograms increased significantly w
ith age (r(s) = 0.4263; p <0.001), whereas type C was not correlated with a
ge. In the UCLP group, the frequency of type B tympanograms decreased with
age (r(s) = -0.4430; p <0.001), the decrease being faster than in the BCLP
group (r(s)= -0.3186; p = 0.001) and the ICP group (r(s) = -0.3378; p <0.00
01)). Type B tympanograms had the highest correlation with a hearing loss o
f 21-40 dB at mean hearing level at speech frequencies (MHLSF) (r(s)= 0.457
4; p <0.001), a lower correlation with a hearing loss of 11-20 dB (r(s) = 0
.2184; p = 0.02) and the lowest correlation with hearing loss above 40 dB.
At the ages of one to three, the frequency of type B is higher in UCLP pati
ents than in the BCLP and ICP groups, decreasing at seven to 12, increasing
again at 13 to 15, and thereafter showing a continuous decrease. In the BC
LP group, the frequency of type B increased significantly at the ages of fo
ur to six and then decreased continuously from seven to 18. In ICP patients
, the changes in the frequency of type B with age are not significant until
the age of 15; at the age of seven, it is higher than in the BCLP and ICP
groups. The type C tympanogram is not typically found in cleft palate patie
nts and its frequency is not correlated with age.
It can be presumed that each type of cleft lip and palate, due to its chara
cteristic conditions in the epipharynx, will favour a different mode of pat
hophysiological development of middle-ear disease.