On the few occasions on which I have performed this operation, no improvement has followed. Others, however, maintain that it may do good in certain cases. This, perhaps, may be possible if it is combined with other intratympanic operations, such as division of the anterior ligament or of the tensor tympani muscle. =Operation.= The paracentesis knife is inserted through the most prominent part of the fold and is made to cut through it from above downwards (Fig. 190, B). If this is successful, gaping of the cut edges takes place and the membrane assumes a less retracted position, and increased hearing and diminution of the subjective symptoms should occur on inflation and rarefying of air within the external ear. INTRATYMPANIC OPERATIONS =General considerations with regard to intratympanic operations and their results.= The chief difficulty, from a clinical point of view, is to determine beforehand the exact pathological changes which already exist within the tympanic cavity. For this reason the indications given with regard to operation are of necessity somewhat empirical. For example, retraction of the tympanic membrane may be due to closure of the Eustachian tube; to adhesions between it and the promontory; to contraction of the tensor tympani, of the anterior ligament, or of the posterior fold. An operation to remove only _one_ of these causes may, therefore, be insufficient; the difficulty is to know what to do. Even if further operations are performed, the result may be negative owing to adhesions having taken place already between the ossicles themselves, or from binding down of the incudo-stapedial joint or of the stapes to the inner wall of the tympanic cavity. And apart from this, even if temporary benefit is obtained, the final result may be worse than that which existed before operation owing to the natural tendency for adhesions to re-form. The prognosis is better in the case of post-suppurative conditions than in the non-suppurative ones. Improvement by operation may be hoped for if a temporary increase in the hearing power, with diminution of the subjective symptoms, is obtained as a result of inflation; especially in those cases in which the malleus is only locally adherent to the promontory. Generally speaking, however, these operations are not recommended, owing to the impossibility of being able to give a good prognosis, and therefore they can only be considered as experimental. _These operations are contra-indicated_--(1) If there be internal-ear deafness. (2) If the stapes (as shown by tuning-fork tests and Gellé’s test) be ankylosed within the fenestra ovalis, especially in the case of otosclerosis. (3) If the membrane be completely adherent to the inner wall at its upper posterior quadrant, especially if this is of long standing, as the stapes will almost certainly also be fixed by adhesions. DIVISION OF INTRATYMPANIC ADHESIONS