and is performed with a peculiar instrument called the lithotome caché. The patient is placed in the same position as with us, but the hands are not bound to the feet. The mode of performing the external incisions, and of opening the urethra, is also the same; but the urethra is opened just behind the bulb; the lithotome

Fig. 92. Division of the prostate with the lithotome caché. 1, Skin of the penis; 2, corpus cavernosum; 3, spongy portion of the urethra; 4, abdominal parietes; 5, symphysis pubis; 6, posterior attachment of the left corpus cavernosum, cut off from the bone which has been removed; 7, penis; 8, commencement of the bulbous portion of the urethra; 9, bulb; 10, membranous portion of the urethra; 11, bladder; 12, vesiculæ seminales; 13, cavity of the bladder; 14, rectum; 15, sacrum and coccyx; 16, sheath of the lithotome; 17, blade of lithotome; 18, prostate; 19, line indicating the incision made by the lithotome on the left side of the prostate; 20, skin behind the sacrum; 21, anus.

caché is now introduced, and its point fixed in the groove of the staff; it is then passed along the groove into the bladder with the blades closed. When the surgeon conceives that he has passed it sufficiently in, he opens the blades to an extent proportioned to the incision he intends making, and in withdrawing the instrument, which is to be done in a perfectly horizontal manner, he divides the neck of the bladder and prostate in an oblique direction downwards and outwards.

Baron Boyer preferred this instrument to all others ; but he employed it in a somewhat different manner. His incision was generally a moderate one, and he preferred dilating it with his finger, or even enlarging it by a second incision, to the risk of cutting too freely. He directed the blade nearly horizontally, and cut towards the ischium until the absence of resistance told him that the prostate was divided across. He then introduced his finger, and dilated the incision downwards, so as to give it somewhat the direction of the external wound.

I should observe that many modern French surgeons employ the blunt-pointed bistoury exactly in the same way we do, but they seem to make their internal incision more freely than we.

CHAPTER XII.

OBSTACLES TO LITHOTOMY.

IN describing the obstacles which may present themselves in the performance of lithotomy, and the accidents that may occur during this operation, or follow it more or less rapidly, I shall pursue the same order that I adopted in speaking of lithotrity. The operation for the extraction of stone from the bladder consists, as I have already said of four parts-viz., the introduction of a grooved staff to guide the cutting instrument; the external and internal incisions; and, finally, the extraction of the calculus.

Now, any circumstance which may impede the due performance of one of these successive proceedings becomes an obstacle, and from the latter arise most of the accidents which accompany or succeed the operation of lithotomy. In the present chapter, I shall chiefly confine my remarks to what occurs during the lateral operation, for the accidents, &c., connected with other methods will be noticed in the parallel which I shall draw between them. The introduction of a grooved staff into the bladder, through the urethra, being one of

the conditions or parts of the lateral operation, anything which impedes this step is an obstacle; but I shall not dwell on this circumstance, as it has been already noticed in reference to lithotrity. I shall only remark, that in cases where the calculus is impacted in the neck of the bladder, and cannot be pushed back into the cavity of that organ, it is evidently impossible to introduce the staff, and another method must be had recourse to.

When the patient can be placed in the usual position, and the perinæum is not deformed by tumours, fistulæ, &c., or any irregularity in the bony structures, the operator experiences no difficulty in making the first incisions in a proper manner. On arriving at the membranous portion of the urethra, the point of the knife is generally guided to the groove of the staff without any difficulty; but care must be taken, while we make the opening into this part, not to wound the rectum, which lies close upon it. Hence many operators advise us to open the membranous portion of the urethra from behind forwards; but this precaution has not been found necessary in the practice of English surgeons.

When the internal incision is effected by the same instrument which was employed for the external incisions, there can of course exist no difficulty in hitting upon the small opening made into the membranous portion of the urethra, since the point of the knife has never quitted the groove of the staff. But in this mode of operating there is always some difficulty in making the point of the knife glide regularly and easily along into the bladder. In the hands even of ex

the groove into the bladder.

perienced operators, it has happened that the groove of the staff has been missed, or the knife has slipped out of the groove, making the incision irregularly and to one side, in a dangerous manner. Moreau, Frère Come, Scarpa, and many other writers on lithotomy, mention examples of this accident. On the other hand, when the beaked knife is substituted for the pointed one, there may be some little difficulty in hitting upon the exact point of the urethra, which we have already opened. This, however, is seldom any obstacle, and may be obviated by keeping the nail of the left forefinger well in contact with the groove of the staff, which the assistant takes care to hold perfectly steady.

What has been said shows that there is little or no difficulty in making our way into the bladder; the great difficulty occurs in getting the stone out of that organ, and a variety of obstacles may impede this important part of the operation. Let us examine them in succession. They may arise from certain conditions of the parts, or depend on the nature, position, and size of the calculus.

The foreign body is extracted with a particular kind of forceps, which we pass along the finger through the external and internal incisions, expand in the cavity of the bladder, close over the stone, and then withdraw in the direction of the external wound. During each of these steps the operator may encounter unexpected obstacles. In the first place, the best operators have occasionally found it difficult to seize the stone, although no impediment could be discovered. Mr. Crosse relates a case in which three