tion, since some Leakage did occur and slight infection of the Lower angle of the
wound, in consequence. There was quite a little oozing of blood from small ves-
sels in front of the sacrum, torn across while enucleating the kidney. From the
depth of the wound and the narrow ness of the field it was found most convenient
to check this oozing by a piece of sterile gauze packing, which was Led oul through
the lower angle of the abdominal wound. The remainder of the wound was sutured
in the ordinary way.

The patient's general condition remained good throughout the operation. Dur-
ing the first three days there was some distention of the intestines with gas, re-



374 CONGENITAL ANOMALIES OE THE KIDNEY AND UEETEE

lieved by enemata. Rectal irrigations of salt solution were given for four days.
The quantity of urine passed after the operation did not vary much from twenty-
four ounces daily. The character of the urine changed at once; the quantity of
albumin diminished to a faint trace and the pus cells diminished to a small amount.
The child became afebrile almost at once: all the septic symptoms disappeared.
Appetite for food returned. The wound healed well, except that a small sinus
remained at its lower angle which discharged a little thin pus. This soon healed
and the child made a perfect recovery.

The kidney was disc-shaped, somewhat lobulated, but nearly circular in outline,
two and a half inches wide and an inch thick. The ureteric pelvis was much di-
lated, thickened and inflamed. The cortex of the kidney contained numerous abscess
cavities scattered here and there, though considerable healthy kidney tissue was
present between them. The capsule of the kidney Avas somewhat adherent, but
not notably thickened. As stated, abundant streptococci were found in the abscess
cavities. A hematogenous origin of the infection seemed to be probable.



4. Fusion Variations. — The commonest variety of kidney fusion is the
Transverse Fusion of the Renal Buds with the Resultant Formation of Renal

Tissue Ventrad of the
Aorta and Post-cava.
" This variation, lead-
ing to the production of
the relatively common
" horseshoe " kidney in
one of its forms, calls
in its genetic interpre-
tation for the assump-
tion of coequal and
symmetrical develop-
ment of both renal
buds, both attaining
the same level at the
same time, but fusing
abnormally across the
narrow, indifferent me-
sodermal zone, typical-
ly separating the cau-
dal poles of the renal
blast emata."

Figs. 113 and 114
are good illustrations of
the resulting adult con-
ditions.

According to the statistics of Krister, compiled from those of Henry Morris
and Socin, " horseshoe " kidney occurs once in 1,100 subjects.




Fig. 113. — Hitman Adult. Caudal pole or " horseshoe " fusion of
kidneys. Isolated preparation with nearly normal axial rotation.
(Columbia University Morphological Museum, No. 3246.)



EMBRYOLOGICAI VARIATIONS IX THE KIDNEY AND URETER 375



Very frequently the fusion determinea the arrest <>f the kidn< lad of

the normal level. In some instances rotation has occurred practically in the
normal degree, the slight caudal band between the t\\<> glands, with the addi-
tional vascular connections, scarcely interfering with the typical vasculariz
of the main glands and the turning <>!' the hila mesad (Fig. 113). In other in-
stances ( Fig. Ill) the implantation <»!' the ureter and vessels is much more ventral
ami more irregular, ami rotation has evidently nol been completed.

End-to-End or " Tandem " Fusion of the Renal Buds.— In this fusion-varia-
tion it must !"• assumed that the buds, during the period of their closest appo-
Bition, are on different

vertical levels so that

the caudal pole of <>nc
renal blastema touches
and fuses with the ceph-
alic pole of the oppo-
site mass. This condi-
tion may result from a
chronological variation
in the renal outgrowths
from the two Wolffian
duels, one bud being
driven off earlier than
the other of the oppo-
site side, or the differ-
en e in level may he
due io actual level-vari-
ation, one bud arising,
as usual, from the "Wolf-
fian duet near its cloaca!
termination, while the
other is derived farther
cephalad from a more
proximal point on the
duct of its side, and

hence occupies from the start a more cephalic position in reference to it- fellow
of the opposite side.

In any case, when this fusion-variation develops, and unless unusual circum-
stances intervene (Figs. 1 1 5, 116), the cephalic kidney appears to take the lead and
to displace the caudal organ across the midline t<> it- own side, interfering with its
normal rotation and producing irregularities in it< vascular supply.

In the following observations a number of instances of this type of fusion are
recorded and figured. They presenl a complete and graded .-erics, proceeding from
the unmistakable condition of complete symmetrica] "horseshoe" kidney, though
atypical development of the same variation, with unequal renal level and disturbed
rotation, to complete tandem fusion, ami finally conclude with an instant
complete assimilation of the two glands into a typical gross anatomical single
kidney with double ureters. The preparations are nil from adult male subjects
received at the anatomical laboratory of Columbia University, except the speci-




Fig. 114. — Human Adult. Cauda] pole or "horseshoe" fusion
of kidneys. Isolated prepa ration with arrested ami atypical
axial rotation. (Columbia University Morphological Museum,
No. 324ti.)



376 CONGENITAL ANOMALIES OF THE KIDNEY AND URETER

men shown in Fig. 117, which I owe to the kindness and skill of Professor Larkin,
Pathologist to Bellevue Hospital.

(a) To correctly interpret the subsequent variations it is desirable to start with
a well-developed instance of the preceding form of typical symmetrical lower pole
fusion, producing a " horseshoe " junction, with nearly normal lumbar level and




Fig. 115. — Human Adult. Crossed renal dystopia with fusion, combined with atypical development
of systemic abdominal venous system. (Columbia University, Anatomical Laboratory Variation
Records.) A. Right ureter. B. Right postcardinal vein. C. Aorta. D. Left postcaval vein.
E. Iliac cross anastomosis. F. Left ureter.



only slight disturbance of renal rotation, causing a more ventral position of pelvis
and vascular connections at the hilum.

Such an instance, in situ, is given by the preparation shown in Fig. 118. The
kidneys in this individual have attained nearly the normal level. Both adrenals are
present and typically situated. The right spermatic vein empties close to the
renal-caval junction, the left at the typical point on the left renal vein. The caudal
poles of the two kidneys, together with the large isthmus of renal substance uniting



EMBRYOLOGICAL VARIATIONS IN THE KIDNEY AND URETER



them ventrad of aorta and post-cava, are Bupplied by additional vascular trunks
of considerable size. Both kidneys have rotated in the normal direction, bul
quite completely. The hila with
the large extrarenal pelves are
placed more ou the ventral sur-
t'ai e than in aonnal glands.

(6) A typical caudal pole
fusion, with arrested migration
and rotation on one side, the
cephalic kidney reaching the nor-
mal lumbar level, and displacing
the caudal kidney up to <>r even
across the median line.

In the preparation shown in
Fig. 11!' the main pari of the
left kidney is normally con-
structed and lias attained the
usual level, with typical main
blood-vessels, adrenal body and
a hilum only slightly displaced
toward the ventral surface. Mi-
gration and rotation have here
occurred normally, but the cau-
dal pole of the left kidney is
fused with the corresponding
extremity of a displaced right
gland, which, by reason of the
ascent of the left organ, has been
pulled across the median line.
with its long axis directed nearly horizontally: migration and rotation have
hcen arrested, and the kidney arches obliquely across the large abdominal
vessels at the common iliac level. The pelvis is exposed on the ventral surface
of the gland, and the principal renal vessels have a nearly vertical direction (cf.
course of vessels in Fig. 112). The right ureter is correspondingly short and de-
scends near the median line, not coming into direct relation with the right
spermatic vessels. 'The preparation illustrates exceedingly well the extent of the
displacing force exerted — by reason of the fusion — on pari of the dominating
kidney, in this case the left one. on the subordinate organ of the other -
The left kidney, in this instance, has reached a practically normal level and, in
accomplishing this ascent, has carried the atypical organ of the opposite side in
the direction of its own line of advance. In comparing Figs. 118 and 119, this
element of predominance on part of one or the other kidney, or arrest of migra-
tion and rotation in one. with unimpeded ascent in the other organ, in cases
caudal pole or "horseshoe" fusion, is quite apparent. The same conditions influ-
ence the adult types of the other forms of renal fusion.

(c) End-to-End or "Tandem" Fusion. — The cephalic kidney here takes the
lead and incorporates the caudal gland of the opposite side into a single _ -
anatomical gland, with two ureters opening typically at the trigonal angles.




Fig. 116. — Human Ann r. Fusion-kidney of V\x. 30.
Isolated. Ventral view. (Columbia University Mor-
phological Museum, No. 3240.)



378 CONGENITAL ANOMALIES OE THE KIDNEY AND UEETEK



An excellent example of this condition is shown in Fig. 117.
The fused kidneys are placed altogether on the left side. The lumbar region
on the right side contained no trace of either renal substance or adrenal body.

The left adrenal is nor-
mal. In this connection
it is worthy to note that,
q notwithstanding the gen-
etic independence of kid-
ney and adrenal body,
and the purely topo-
graphical association of
the two organs in nor-
mal adult conditions, dis-
turbances in the meta-
nephric development are
-" frequently associated with
j similar faults in the ad-
renal structure.

In this case the fused
compound kidney is a
very massive organ, meas-
uring 7 inches in the
vertical and 3.75 inches
in the greatest transverse
diameter. The ureteric
implantations and the
vascular connections are
distributed over the ven-
tral surface. The ceph-
alic and larger part of
the compound gland is
evidently furnished by
the left renal bud, while
caudal and smaller por-
tion represents the ele-
ment contributed by the
displaced primitive right
kidney. The line of prob-
able fusion is indicated
by a deep furrow, con-
taining in its cephalic
portion large arterial and venous branches common to both organs, while the ureter
of the primitive right kidney emerges from its distal portion, descending obliquely
caudad and to the right, across the large abdominal vessels, to the right vesical
ureteric opening of a well-built trigone. The fusion in this case has evidently oc-
curred between the caudal pole of the left and the cephalic pole of the right kidney
combined with a certain amount of lateral overlap of the two renal buds, pro-
ducing in addition a marginal confluence and establishing a very complete union of




Fig. 117. — Human Adult. Cephalo- caudal end-to-end or "tan-
dem " fusion of kidneys, with complete crossed dystopia of right
kidney. (Columbia University Morphological Museum, No.
3248.) A. Postcava. B. Right renal vein. C. Right sper-
matic vein. D. Right ureter. E. Right vesical ureteric open-
ing. F. Left adrenal. G. Left renal vein. H. Probable line
of end-to-end fusion of kidneys. /. Left spermatic vein. J. Left
ureter. K. Left vesical ureteric opening.



EMBRYOLOGICAL VARIATIONS IN THE KIDNEY AND URETER 379

the two fundaments into a single gross anatomical kidney with double ureters,
each < 1 1 1 < - 1 possessing a separate vesical orifice al the lateral angles of ;i typical
trigone. Closely analyzed, the fusion musl Kave occurred as shown in the schematic




Fig. US. — Human Adult. Caudal polo or "horseshoe" fusion of kidneys. Situs preparation.
(Columbia University Morphological Museum, \<>. 3247. ^ A. Post cava. B. Right renal vein.
C. Highl ureter. D. Bladder. B. Aorta. /•'. Lett renal vein. (.'. Left spermatic vein. //.

Left ureter.



Pig. 120 involving tin 1 caudal pole of tin' left kidney and the cephalic pole o( the
displaced right kidney. The caudal pari of the medial margin of the left kidney
overlapped the cephalic part of the medial border of the right gland, and corre-
sponding surface areas of the ventral as|><vi of the right ami dorsal asped of the



380 CONGENITAL ANOMALIES OF THE KIDNEY AND URETEK



left kidney became confluent, as indicated in the shaded area of Fig. 120. Ascent
and rotation have evidently proceeded normally, as far as possible under the
conditions, in the case of the ascended kidney, which has carried the incor-
porated mass of the
right gland with it com-
q. pletely across the me-
dian line. Typical axial
rotation of the displaced
right kidney has taken
place, bringing the ure-
tt teric implantation to
what would have been
the mesal margin of
the gland if normally
situated on its own
side. The right ureter
emerges from the com-
pound gland near the
caudal limit of the com-
mon fused area (Figs.
117 and 120). The sur-
face of the organ, there-
fore, situated caudad and
mesad of the groove in-
dicating the area of fu-
sion belongs to the right
kidney, and would form
the lower part of the ven-
tral surface of the same
if normally situated on
the right side.

Ureters. — The ceph-
alic (left) ureter de-
scends obliquely over the
ventral surface of the
srland to the




J



Fig. 119. — Human Adult. Caudal pole renal fusion with initial
stage of crossed dystopia of right kidney. (Columbia Univer-
sity Morphological Museum, No. 3103.) A. Aorta. B. Postcava.
C. Right renal vein. D. Right spermatic vein. E. Right
ureter. F. Bladder. 67. Left adrenal. H. Left renal vein.
/. Left spermatic vein. J . Left ureter.



lateral
margin, crossed by the
left spermatic vessels,
and then curves grad-
ually to its vesical ter-
mination.
The lower (right) ureter, shorter than the left duct, emerging near the caudal
end of the lateral margin, takes a sharp turn to the right across aorta and cava,
descends nearly in the midline to the bladder, bends again to the right to reach its
point of engagement in the bladder wall, and, reversing its direction, traverses
the same to a normal ureteric orifice at the right angle of a perfectly formed
trigone.



EMBRYOLOGICAL VARIATIONS IN THE KIDNEY AND URETER 381




I'ic 1'2<>. — Schema Ii.i.<'-tu.\ti\-<;
Type of Renal Blastema Fus-
ion in Preceding Preparation.
<i. Area of fusion, b, Hitrlit kht-
ney. c. Right ureter. •!. Left
kidney. <-. Left ureter.



Professor McMurrich 1 has described ;i case of fusion variation almosi iden-
tical with the one above described. He tabulation with reference
fcwenty-eighl similar cases heretofore recorded in
the literature of anatomical^ single unilateral

kidneys, produced by fusion of the renal buds, / — \ — d

and possessing two ureters opening Dormally into
the bladder.

Another Bimilar case is reported by E. C.
Hill. 2

We have, therefore, to deal with a perfectly
well-defined embryonic variation of the kidneys
which, while rare, assumes such a regular type,
when i( does occur, as to make the condition one
of greal practical importance, from the clinical
standpoint. The cystoscopic examination would Bhow
;i normal or practically normal trigone with right
and left pateni ureteric openings, both delivering

urine to the bladder. This would Suggest, but does

not necessarily prove, the presence of two separate

and distinct kidneys. "With a perfectly normal
ureteric bladder Held the individual may possess only a single unilateral gross
anatomical kidney, on one or the other side, the product of re or less com-
plete fusion of the original bilateral renal blastemata and crossing one of them
to the opposite side. Moreover, as pointed out by McMurrich and shown in
one of Kruse's cases, no matter how perfect the fusion may be, the two kidneys
retain their functional independence of each other, and their tubular elements
do not communicate. Hence it is quite possible, as actually occurred in the case
Kruse referred to, that one portion of a <rross single fusion kidney corresponding
to the pari contributed by one of the renal buds should degenerate pathologically,
while the other retains its normal parenchymatous structure. Consequently, even
the differentia] urinary analysis by ureteric catheterization will not infallibly
determine either the side of the affected organ or its gross structural independence
of the remaining normal kidney tissue. The importance of these facts from the
clinical standpoint becomes at once apparent if the question of nephrectomy or
other extensive renal operation is under consideration. McMurrich's tabulation
shows that the variation in 35 recorded cases occurs in to per cent on the righl
and in 60 per cent on the left side, and that out id' % l'-\ cases IS per cent were
males ami 22 per cent females. These figures, therefore, indicate a decided pre-
ponderance on the left side and in males.

The only possible mean- of determining the position and course of the ure-
ters in doubtful cases is by an X-ray picture of styleted ureteral catheters
in situ, passed up to the ureteric pelves. Such a picture would show the

1 J. Playfuir McMurrich, "Crossed Dystopia of the Kidney, with Fusion," .Jour. Aunt, ami
Phys., vol. xxxii. p. 652.

l.Ki'ii C Hill. •( )n the Embryonic Development of a Case of Fused Kidneys," Johns Hop-
kins Hosp. Bull., vol. wii, No. 181, April. L906.



382 CONGENITAL ANOMALIES OF THE KIDNEY AND URETER

course of the ureter of the crossed kidney in this type of fusion, and would
form a rational basis for an exploratory operation in case the other signs and

symptoms seemed to de-
mand surgical interfer-
ence with the kidney. I
have used this method
in a number of instances
of supposed malplaced
or fused kidney with
satisfactory results.

A unique example
of crossed renal dysto-
" pia with fusion was ob-
served by Prof. George
S. Huntington :

The case, observed in
the body of a male white
subject fifty-six years of
age, is one of unilateral
single kidney of the right
side with double ureter,
and is shown in situ in
Fig. 115.

Fig. 116 shows the
isolated kidney with the
proximal parts of the
two ureters in the ven-
tral view, while Figs.
121 and 122 show the
bladder and prostate in
the ventral and dorsal




E



F



G



Fig. 121. — Human Adult. Bladder of Fig. 115. Ventral view.
(Columbia University, Morphological Museum, No. 3250.) A.
Right ureter. B. Right vesical ureteric orifice. C. Right
ejaculatory duct. D. Bladder. E. Left vesical ureteric orifice.
F. Left ejaculatory duet. G. Opening of prostatic utricle.



views.



The case is, as will appear, one of crossed renal dystopia with fusion, the cephalic
pole of the right uniting with the caudal pole of the left gland, combined with an em-
bryonal variation of the large abdominal venous trunks. The fusion is very complete,
and the resulting compound organ closely imitates in shape, position and general
appearance a normal, large, single right kidney with complete ureteric reduplication.

(For an analysis of the mode of production of these variations, the reader
is referred to Professor Huntington's paper.)



VARIETIES AND PATHOLOGICAL RESULTS OF CONGENITAL ANOMALIES

OF THE URETER

From the preceding history of the development of the kidney and ureter
it can be readily understood that the ureter may be doubled either throughout



VARIETIES OF CONGENITAL ANOMALIES OF THE URETER



ii- entire length or for a greater or less distance below the kidney, the two
ureters uniting in the latter cas< at some point above the bladder i<> empl
ii single canal in the norma] situation. Winn the ureter remains « i« »n 1>1«-
throughout, one ureter, usually the lower, may enter the bladder a< the nor-
mal trigonal angle ; the
other, upper ureter,
will then enter al a

lower point either in

the trigonal area, or
in the region of the
interna] sphincter, or
in the prostatic ure-
thra just lateral to the
orifice of the ejaeula-
tory duet, ot in the
seminal vesicle, or in A

the vas deferens. 1 £
the upper ureter enters
the bladder at the nor- B
nial trigonal angle, then
the lower ureter will
enter the bladder at C
some higher point in
its floor or posterior
wall. When double ure-
ters enter the bladder
by patent and ample
orifices the condition is
in itself of no patho-
logical significance, bul

one of these ureters

may become infected

from the bladder, or the posterior portion of the kidney, drained by one ureter,

may be the seat of infection; in this connection it is to be borne in mind that

the ureter proceeding from the upper portion of the kidney empties into the

bladder al a hirer point than the other.

When one or other of the ureters empties in an abnormal situation, in the
urethra, the vagina, the seminal vesicle, or the vas deferens, or when one of
the ureters empties at any point by an abnormally small and insufficient orifice,
several pathological conditions are possible. Among these, the commonest and
most important is the dilatation of the ureter, and hydronephrosis and atrophy
of that portion of the kidney drained by that ureter.

"When the ureter empties into the vagina there will be dribbling of urine:
when the ureter empties into the prostatic urethra there may or may n




Fig. 122. -Same Preparation. Dorsal view. A. Left vas deferens

B. I. oft ureter. C. Left seminal vesicle. D. Bladder. /.". Right

ureter. F. Right seminal vesicle. G. Prostate.



384 CONGENITAL ANOMALIES OF THE KIDNEY AND URETEK

dribbling of urine. The fact that an individual has dribbling of urine, and
yet is able to empty the bladder in a normal manner, demonstrates the pres-
ence of an abnormal ureteric opening. When the ureter empties into the sem-
inal vesicle, the ejaculatory duct, or vas deferens, these structures will be
dilated, and such dilatation may produce a sac which projects forward and
causes an anterior bulging of the posterior bladder wall. In certain cases
when a ureter empties into the bladder by a very narrow opening, or when, as
sometimes happens, such an opening is closed completely from any cause, a
cystic tumor of the bladder may develop, situated between the muscular coat
and the mucous membrane; such a cyst may remain small and produce no
symptoms ; it may grow larger, so that it presses upon the urethral orifice and
causes dysuria or retention. It may grow so large as to completely fill and
distend the bladder; it may even compress the other ureter, and thus cause
complete hydronephrosis with atrophy of the entire kidney. Such cases are
peculiarly susceptible to infection with a resulting infected hydronephrosis.
In other cases the normal ureter of the other side may be compressed, resulting
in interference with the function of the opposite kidney and death from uremia.
In the female an obstructed ureter may cause, first, a cystic tumor of the
bladder and interference with urination. Continued straining efforts may force
such a dilated ureter into the urethra, and cases have been observed where
the tumor projected beyond the external urethral orifice. In those cases of
abnormal ureters which have produced symptoms the results have been far more
disastrous in females than in males ; in the former the individuals have rarely
reached adult life, in the latter a number of these individuals have lived to
advanced age; in some no symptoms have been produced, the condition having
been observed only after death, as in the specimens collected by Professor
Huntington.

In others symptoms have occurred, sometimes early, sometimes not until
advanced age. When no symptoms have occurred the diagnosis will, of course,
not be made during life. As might be expected from what we know of the
physiology of urination, and of the relative powers of the compressor urethra?
and sphincter muscles of the bladder, a ureteric opening in the prostatic urethra
does not necessarily produce dribbling of urine.

DIAGNOSIS

When a patient, male or female, gives a history of dribbling of urine from
infancy, and at the same time is able to empty the bladder normally, the diag-