Surgical Anatomy Part 38

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 52.--Figure 1

FIGURE 2.

A, D, F, G, H, I, K, L refer to the same parts as in Fig. 1, Plate 52.

B. The urethra.

C. Cowper's glands between the two layers of--

E. The deep perinaeal fascia.

M. The bulb of the urethra.

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 52.--Figure 2

PLATE 53.

FIGURE 1.

A, B, C, E, F, G, H, I, K, L refer to the same parts as in Fig. 2, Plate 52.

D D. The two crura p.e.n.i.s.

M. The urethra in section

N N. The r.e.c.t.u.m.

O. The sacro-sciatic ligament.

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 53.--Figure 1

FIGURE 2.

A, B, D, G, H, I, K, L, O refer to the same parts as in Fig. 1, Plate 53.

C C. The two lobes of the prostate.

F. The r.e.c.t.u.m turned down.

M. The membranous part of the urethra.

N N. The vesiculae seminales.

P. The base of the bladder.

Q Q. The two vasa deferentia.

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 53.--Figure 2.

COMMENTARY ON PLATES 54, 55, & 56.

THE SURGICAL DISSECTION OF THE MALE BLADDER AND URETHRA.-- LATERAL AND BILATERAL LITHOTOMY COMPARED.

Having examined the surgical relations of the bladder and adjacent structures, in reference to the lateral operation of lithotomy, it remains to reconsider these same parts as they are concerned in the bilateral operation and in catheterism.

Fig. 1, Plate 54, represents the normal relations of the more important parts concerned in lithotomy as performed at the perinaeal region. The median line, AA, drawn from the symphysis pubis above, to the point of the coccyx below, is seen to traverse vertically the centres of the urethra, the prostate, the base of the bladder, the a.n.u.s, and the r.e.c.t.u.m. These several parts are situated at different depths from the perinaeal surface. The bulb of the urethra and the lower end of the bowel are on the same plane comparatively superficial. The prostate lies between these two parts, and on a plane deeper than they. The base of the bladder is still more deeply situated than the prostate; and hence it is that the end of the bowel is allowed to advance so near the pendent bulb, that those parts are in a great measure concealed by these. As the apex of the prostate lies an inch (more or less) deeper than the bulb, so the direction of the membranous urethra, which intervenes between the two, is according to the axis of the pelvic outlet; the prostatic end of the membranous urethra being deeper than the part near the bulb. The scalpel of the lithotomist, guided by the staff in this part of the urethra, is made to enter the neck of the bladder deeply in the same direction. On comparing the course of the pudic arteries with the median line, A A, we find that they are removed from it at a wider interval below than above; and also that where the vessels first enter the perinaeal s.p.a.ce, winding around the spines of the ischia, they are much deeper in this situation (on a level with the base of the bladder) than they are when arrived opposite the bulb of the urethra. The transverse line B B, drawn in front of the a.n.u.s from one tuber ischii to the other, is seen to divide the perinaeum into the anterior and posterior s.p.a.ces, and to intersect at right angles the median line A A. In the same way the line B B divides transversely both pudic arteries, the front of the bowel, the base of the prostate, and the sides of the neck of the bladder. Lateral lithotomy is performed in reference to the line A A; the bilateral operation in regard to the line B B. In order to avoid the bulb and r.e.c.t.u.m at the median line, and the pudic artery at the outer side of the perinaeum, the lateral incisions are made obliquely in the direction of the lines CD. In the bilateral operation the incision necessary to avoid the bulb of the urethra in front, the r.e.c.t.u.m behind, and the pudic arteries laterally, is required to be made of a semicircular form, corresponding with the forepart of the bowel; the cornua of the incision being directed behind. In the lateral operation, the incision C through the integument, crosses at an acute angle the deeper incision D, which divides the neck of the bladder, the prostate, &c. The left lobe of the prostate is divided obliquely in the lateral operation; both lobes transversely in the bilateral.

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 54, Figure 1.

Fig. 2, Plate 54.--If the artery of the bulb happen to arise from the pudic opposite the tuber ischii, or if the inferior hemorrhoidal arteries be larger than usual, these vessels crossing the lines of incision in both operations will be divided. If the superficial lateral incision C, Fig. 1, be made too deeply at its forepart, the artery of the bulb, even when in its usual place, will be wounded; and if the deep lateral incision D be carried too far outwards, the trunk of the pudic artery will be severed. These accidents are incidental in the bilateral operation also, in performing which it should be remembered that the bulb is in some instances so large and pendulous, as to lie in contact with the front of the r.e.c.t.u.m.

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 54, Figure 2.

Fig. 1, Plate 55.--When the pudic artery crosses in contact with the prostate, F, it must inevitably be divided in either mode of operation.

Judging from the shape of the prostate, I am of opinion that this part, whether incised transversely in the line B B, or laterally in the line D, will exhibit a wound in the neck of the bladder of equal dimensions.

When the calculus is large, it is recommended to divide the neck of the bladder by an incision, combined of the transverse and the lateral. The advantages gained by such a combination are, that while the surface of the section made in the line D is increased by "notching" the right lobe of the prostate in the direction of the line B, the sides of both sections are thereby rendered more readily separable, so as to suit with the rounded form of the calculus to be extracted. These remarks are equally applicable as to the mode in which the superficial perinaeal incision should be made under the like necessity. If the prostate be wholly divided in either line of section, the pelvic fascia adhering to the base of this body will be equally subject to danger. By incising the prostate transversely, B B, the seminal ducts, G H, which enter the base of this body, are likewise divided; but by the simple lateral incision D being made through the forepart of the left lobe, F, these ducts will escape injury. [Footnote] On the whole, therefore, the lateral operation appears preferable to the bilateral one.

[Footnote: As to the mode in which the superficial and deep incisions in lateral lithotomy should be made, a very eminent operating surgeon remarks--"a free incision of the skin I consider a most important feature in the operation; but beyond this the application of the knife should, in my opinion, be extremely limited. In so far as I can perceive, there should be no hesitation in cutting any part of the gland which seems to offer resistance, with the exception, perhaps, of its under surface, where the position of the seminal ducts, and other circ.u.mstances, should deter the surgeon from using a cutting instrument."--Wm. Fergusson, Practical Surgery, 3d Am. Ed., p. 610.]

[Ill.u.s.tration: Abdomen, showing blood vessels and other internal organs.]

Plate 55--Figure 1.

Fig. 2, Plate 55.--The muscular structures surrounding the membranous urethra and the neck of the bladder, and which are divided in lithotomy, have been examined from time to time by anatomists with more than ordinary painstaking, owing to the circ.u.mstance that they are found occasionally to offer, by spasmodic contraction, an obstacle to the pa.s.sage of the catheter along the urethral ca.n.a.l. These muscles do not appear to exist in all subjects alike. In some, they are altogether wanting; in others, a few of them only appear; in others, they seem to be not naturally separable from the larger muscles which are always present. Hence it is that the opinions of anatomists respecting their form, character, and even their actual existence, are so conflicting, not only against each other, but against nature. In Fig. 2, Plate 55, I have summed together all the facts recorded concerning them, [Footnote]

and on comparing these facts with what I have myself observed, the muscles seem to me to a.s.sume originally the form and relative position of the parts B C D E F viewed in their totality. Each of these parts of muscular structure arises from the ischio-pubic ramus, and is inserted at the median line A A. They appear to me, therefore, to be muscles of the same category, which, if all were present, would a.s.sume the serial order of B C D E F. When one or more of them are omitted from the series, there occurs anatomical variety, which of course occasions variety in opinion, fruitless though never ending. By that interpretation of the parts which I here venture to offer, and to which I am guided by considerations of a higher law of formation, I encompa.s.s and bind together, as with a belt, all the dismembered parts of variety, and of these I construct a uniform whole. Forms become, when not viewed under comparison, as meaningless hieroglyphics, as the algebraic symbols a + c - d = 11 are when the mind is devoid of the power of calculation.

[Footnote: The part C is that alone described by Santorini, who named it "elevator urethrae," as pa.s.sing beneath the urethra. The part B is that first observed and described by Mr. Guthrie as pa.s.sing above the urethra. The part F represents the well-known "transversalis perinaei,"

between which and the part C there occasionally appears the part E, supposed to be the "transversalis alter" of Albinus, and also the part D, which is the "ischio bulbosus" of Cruveilhier. It is possible that I may not have given one or other of these parts its proper name, but this will not affect their anatomy.]