Pyelography (pyelo-ureterography) a study of the normal and pathologic anatomy of the renal pelvis and ureter

Preface

It is now almost ten years since Voelcker and von Lichtenberg first succeeded in demonstrating by means of pyelography the outline of the human renal pelvis and ureter. This method, which was at first disregarded, has been recently more fully developed and appreciated. In all this time no comprehensive collection of the various types of pelvic outline has been published. The interpretation of the great variety of pelvic deformities outlined in the pyelogram is difficult and is possible only through familiarity with the various types. The publication of a series of plates embodying many of the different outlines of the pelvis and ureter seen in routine pyelography would seem to be of some practical value. With this end in view I have selected a number of plates from the several thousand made at the Mayo Clinic during the past five years, trusting that these, together with their description and comments, may increase the value of the method and permit the more general usage which it deserves.

I wish to acknowledge my indebtedness to Drs. William J. and Charles H. Mayo for placing at my disposal the clinical material for this monograph; to Dr. A. B. Moore and Mr. E. L. Taylor, of the roentgenographic department for making the original radiographic plates ; to Dr. Franz Wildner for assistance in the compilation of data; to my associates, Drs. G. J. Thomas and J. L. Crenshaw, for assistance in the development of the technic; and to Mrs. M. H, Mellish and staff for assistance in compiling the literature, editing, and proof-reading.

William F. Braasch.

Rochester, Minn.

March, 1915

Chapter I The History Of Pyelography

Probably the first attempt to render the urinary tract opaque to the x-ray was made by Tuffier ^ in 1897. He suggested the simultaneous combination of an opaque ureteral catheter and radiography. Schmidt and Kolischer," in 1901, independently suggested the same method and published radiograms which showed the course of the ureter and the situation of the renal pelvis by means of a fused wire inserted into the ureteral catheter with simultaneous radiography. They developed the possibilities of this method and demonstrated its value in various conditions. In 1901 Lowenhardt ^ described somewhat similar methods, as did also von Illyes ^ the following year. In 1905 Fen wick ^ suggested for the same purpose the use of a ureteral bougie with its walls impregnated with metal. These methods were the forerunners of the use of Uquid solutions opaque to the :c-ray for the purpose of rendering the outline of the ureter and renal pelvis visible in the radiogram, a method which has been called pyelography or, to be more exact, pyelo-ureterography.

The development of the history of pyelography may be considered from the following standpoints: (1) Technic; (2) diagnostic data; and (3) accidents arising from its use.

Technic. — Probably inspired by his ability to outline the alimentary tract with bismuth, Klose,*' in 1904, sug- 2 17 gested the injection of an emulsion of bismuth into the pelvis and the ureter with simultaneous radiography. This method failed, however, because the resulting shadow was uncertain, and it was found difficult to remove the particles of bismuth w^hich adhered following the injection. It remained for Voelcker and von Lichtenberg,^ in 1906, first to demonstrate successfully the complete outline of the ureter and renal pelvis in the radiogram. They were the first to suggest the use of colloidal silver (collargol) for this purpose. In attempting to outline the bladder in the radiogram it was discovered in one of their plates that the solution had entered the ureter and renal pelvis also, causing them to be outlined in the radiogram. Encouraged by this discovery, they injected a 2 per cent, solution, and later a 5 per cent, solution, through the ureteral catheter into the pelvis of the kidney and were able to report the results of a successful series of pyelograms. The value of this method was slow to be recognized, and, consequently, received but little attention until three or four years later. Within the last three or four years, however, the method has received wide-spread recognition, and is at present extensively employed.

Various other forms of colloidal silver have been suggested by some observers. Ai-gyrol, in solutions of 40 or 50 per cent., was advanced by Keyes ^ in 1909; silver oxid or cargentos, by Uhle and Pf abler ^ in 1910; nargol and electrargol, by others, ^"arious solutions other than colloidal silver have been advocated. In 1913 Doderlein and Kronig ^° suggested the use of xeroform (15 to 20 per cent, in olive oil). Attempts were made to render the outline of the pelvis and ureter visible by means of injecting gas instead of liquid solutions. Bm'khardt and Polano,^^ in 1907, first suggested injecting oxygen into the pelvis for this purpose. In 1911 von Lichtenberg and Dietlen '- reported a series of pyelograms made with the use of oxygen, and recommended its substitution for colloidal silver. However, the use of the gaseous medium did not receive wide-spread recognition, since the resulting outline was frequently uncertain and hard to differentiate from that of gas in the bowel. The use of an emulsion of silver iodid was suggested first by Uhle and Pfahler.^ Recently Kelly and Lewis ^^ (1913) have also recommended it and demonstrated a series of pyelograms where it was used to advantage. They claim that it cast as good a shadow as colloidal silver, without causing any of the ill results which have been reported to follow the latter.

The various solutions had usually been injected into the renal pelvis by means of a hand syringe. Since the degree of pressure by this method was uncertain, and since it was impossible always to determine when the capacity of the pelvis had been reached, effort was made to discover a safer method of injection. For the purpose of overdistending the renal pelvis a gravity method apparatus was first suggested by Baker " in 1910. The same year this method was first applied to pyelography by Uhle ^ and his coworkers. They placed the solution in a tube, which was held at a short distance above the level of the patient, and allowed the fluid to distend the pelvis and ureter by gravity. Oehlecker,^^ in 1911, also advised injecting the solution by means of the gravity method, rather than by the syringe. In the same year a similar method was suggested by Stanton ^^ and Bruce. ^^ In 1913 Thomas ^^ described a simple apparatus for the bilateral injection by the gravity method. Following the recommendation of observers with wide experience, the gravity method is now almost universally employed.

The importance of a careful preparation of the injected solution was emphasized by the writer in 1913.^^ He recommended that the colloidal silver crystals be pulverized, dissolved in lukewarm water, and then carefully filtered; otherwise in the 10 per cent, solution large particles of silver might be deposited in the pelvis and possibly cause irritation. He further recommended that there be no delay in making the radiogram after the kidneys had been catheterized, and that the injection and radiogram should be made simultaneously. Kidd '^^ also, in 1914, urged that the renal pelvis should be subjected to pressure by the solution injected but a short time — preferably less than a minute.

The position of the patient while the pyelogram is being made is usually dorsal. In 1912 Fowler ^^ recommended a subsequent pyelogram made in the erect position, in order to observe the degree of renal excursion. Schramm,^- in 1913, recommended the moderate Trendelenburg position, in order more completely to distend and outline the ureter.

The size of the plate varies with the purpose for which it is made, and with the size of the field required. In 1911 Oehlecker ^"^ recommended a 40 x 50 cm. plate, so that the entire urinary tract might be outlined. He emphasized the value of comparing the outlines in both renal pelves and ureters. Objections to this method may be raised on the grounds of possible injury to both kidnej^s because of incorrect technic.

The opinions of different authors vary as to the degree of pain that should be caused on injection of the solution.

The majority of them say that mild pain should be the signal for stopping the injection. In 1913 Childs and Spitzer -^ stated that severe pain should be the signal for ceasing injection. The writer, ^^ however, has claimed (in 1913) that pain is unnecessary and should be avoided.

The greater the concentration of the solution, the clearer will be the outline following its injection, but it is a common experience that the more concentrated solutions are irritating. A 10 per cent, solution is now most commonly employed, though it is maintained by some that a 5 per cent, solution will usually suffice to outline with completeness and safety. In 1908-09 Albarran and ErtzbischofT ^^ recommended a 7 per cent, solution, as did also Nogier and Reynard -^ in 1911.

The possibility of outlining the dilated ureters after filling the bladder with colloidal silver was first suggested by von Lichtenberg ^^ in 1909. In 1911 Clark 2' also described this method, advising the Trendelenburg position, so that the fluid would more readily enter the ureters. In 1913 the writer ^^ recommended the method in selected cases, but called attention to the fact that its use was necessarily limited.

Diagnostic Data. — Attention was first called to the value of pyelography as an aid to diagnosis by Voelcker and von Lichtenberg ^ in 1906. They emphasized its value in the diagnosis of hydronephrosis, and also suggested that it might prove to be of use in the diagnosis of renal tumor and anomaly, although they did not then refer to any actual demonstration of such data. Albarran and Ertzbischoff ^^ were probably the first to follow the suggestions of Voelcker and von Lichtenberg,^ and in 1908 published a summary of their experiences. Although they suggested the various possibilities of the method, their results were incomplete and unsatisfactory. It remained for later observers to note the full value of the method and to develop its possibilities in the diagnosis of numerous conditions in which its use has been demonstrated. Diagnostic data derived from pyelography may be found in articles by the writer from 1909 to the present time (1914).^^ In papers read in 1909 "^ and 1910 ^° he called attention to its value in the diagnosis of the following conditions: (1) Normal pelvis; (2) hydronephrosis; (3) pyelitis; (4) pyonephrosis; (5) renal tuberculosis; (6) renal tumor; (7) renal and ureteral anomaly; (8) monoc3^stic and polycystic kidney; (9) identification of renal shadows; (10) localization of renal shadows; (11) identification of ureteral obstruction; and (12) as an aid to ascertain renal function. This summary may be said to include practically all possible conditions in which the method has been found to be of value.

The early writings of Voelcker and von Lichtenberg demonstrated the possibility of diagnosing the existence of a hydronephrosis by means of pyelography, von Lichtenberg again described several types of hydronephrotic dilatation in 1909,-^ and referred to the diagnosis of movable kidney and ureteral kinks. In 1909 Keyes ^ described in detail changes taking place in the calyces as the result of mechanical obstruction. He coined the term ''plug-hat pelvis" to describe the appearance of the hydronephrotic pelvis. In a paper read in 1909 -^ the writer also described various types of hydronephrosis, with illustrations, and in 1911 ^^ he called attention to the value of the method in the diagnosis of early hydronephrosis. In 1911 Key ^- reported several cases of hydronephrosis with excellent illustrations. In 1912 Fowler ^^ emphasized its value in the diagnosis of small dilatation of the pelvis. In 1913 Cabot"*'' further emphasized this point, and stated that it is frequently the only method whereby early hydronephrosis can be diagnosed. He also claimed the relation of the ureter to the pelvis to be of diagnostic importance in early hydronephrosis. In 1911 Oehlecker^'^ referred to the value of pyelography in the diagnosis of dilatation in hydronephrosis and pyonephrosis. He described several pyelograms showing the dilatation of the renal pelvis and ureter which frequently accompanies pregnancy. In 1911, and again in 1913, Walker,^* in a paper devoted to the diagnosis of hydronephrosis, described further details of the method. In 1913 Voelcker ^^ gave a detailed description of the gradual process of pelvic dilatation, and differentiated between the mechanical and inflammatory types of dilatation. Probably the most recent paper on the subject is one by the writer ^^ in which the details and possible variations of the outhnes in the different stages of hydronephrosis are described. The value of the method in the diagnosis of hydronephrosis has been recognized by numerous other observers, among whom may be mentioned Nogier and Reynard,25 Bruce," Necker,^^ Jaches and Furniss,^^ Keene,^^ and Legueu, Papin, and Maingot.'*'' In 1912 Fowler ^^ called attention to the method of making a pyelogram with the patient first in the dorsal and then in the erect position. In this manner the full degree of excursion of both kidneys, when movable, as well as the consequent course of the ureters, can be more accurately ascertained.

The writer was probably the first to describe the various changes in the outhne of the pelvis and ureter as the result of inflammation.29' 30 In a recent article (1914) he described further details of the various changes found in the different stages of inflammatory destruction,^^ In 1911 Key ^^ published several excellent plates showing dilatation as the result of infection. In a paper written in 1912 dealing with the value of pyelography in the diagnosis of various conditions Paschkis and Necker ^- state that the dilatation seen with inflammation is due to ureteral obstruction. In 1913 Voelcker ^^ described in detail the stages of inflammatory change in the pelvic outline. In 1913 Keene ^^ also described the form of dilatation seen in both the renal pelvis and the ureter as a result of inflammation. In 1911 Clark ^^ described the method of outlining the ureter dilated as the result of inflammation by means of injecting colloidal silver solution into the bladder with the patient in the Trendelenburg position and simultaneous radiography.

In 1910 the writer ^^ called attention to the value of pyelography in the diagnosis of renal tuberculosis in certain doubtful cases. In 1911 Oehlecker ^'^ stated that the method is occasionally of value in the diagnosis of renal tuberculosis. Von Lichtenberg and Dietlen ^^ substantiated these reports in 1911, and described the various possible deformities seen even in advanced tuberculosis. In the same year Nogier and Reynard ^^ described a case of renal tuberculosis diagnosed by means of pyelography. In 1911 Key ^^ also described the possible value of pyelography in certain cases of renal tuberculosis.

Although the diagnosis of renal tumor by means of the pyelogram was suggested by Voelcker and von Lichtenberg/ as well as by Albarran and Ertzbischoff,-^ they did not illustrate nor describe the many possible deformities. In 1909,-^ and again in 1912/^ the writer detailed the various deformities which accompany tumor, and illustrated their more important phases. In 1909 von Lichtenberg ^'^ also called attention to the possibility of peh'ic deformity as the result of renal tumor. In 1911 Nojj;ier and Reynard -'-' stated that occasionally renal tumor could be diagnosed in no other way. In 1911 Oehlecker i'' also called attention to the possibility of diagnosing renal tumor by means of the pyelogram. These findings were corroborated subsequently by Jaches and Furniss,'^'* Keene,^'^ and others. The writer -^ has called attention to the value of the method in differentiating tumor in the extrarenal organs from renal neoplasm. In 1914 Kidd -" referred also to the aid given in the differential diagnosis of abdominal tumor.

Although Voelcker and von Lichtenberg " were the first to suggest the use of pyelography in the diagnosis of congenital anomaly in the urinary tract, the first detailed data of the possibilities of the method were furnished by the writer in 1910,^° and again in 1912.'^ In 1909 von Lichtenberg -^ cited a case of dystopic kidney diagnosed by means of pyelography. In 1911 Oehlecker ^^ emphasized the value of the pyelogram in the diagnosis of congenital anomaly, and cited a case with duplication of the ureter and pelvis. In the same year Nemenow^^ made a similar observation, and cited a case of pelvic kidney which was diagnosed by means of pyelography. In 1911 Seelig ^"^ described a case with bilateral duplication of the pelves diagnosed by means of pyelography. In 1914 Joseph ^^ described the value of the method in the diagnosis of a series of congenital anomalies. In 1914 Kidd ^° asserts that congenital anomaly is frequently overlooked, and that its existence can frequently be ascertained by means of pyelography, or pyeloradiography, as he terms the method.

That pyelography could be of considerable value in the diagnosis of polycystic kidney was suggested in 1910 by the writer, ^° who demonstrated with illustrations some of the varieties of deformity accompanying this condition. His later publication suggested that it might also be of value in the diagnosis of solitary cysts.

The value of pyelography in the identification as well as the localization of renal shadows was first noted by the writer in 1910,^0 and later fully described ^^ (1913). In 1911 Oehlecker ^^ also described various changes in the pelvic outline as the result of stone, and called attention to their value in the identification of stone. In the same year Holland ^^ described the value of the method in the identification of renal and ureteral shadows, calling attention to its use in the differential diagnosis of gall-stone shadow. In 1911 von Lichtenberg and Dietlen ^^ wrote of the desirability of localizing stone shadows by means of pyelography, and advised the use of oxygen instead of colloidal silver for this purpose. In 1911 Nogier and Reynard,^^ and in 1913 Keene,^^ recommended pyelography in the diagnosis of renal stone.

The value of the method in the identification of ureteral obstruction, including that due to lithiasis, was described by the writer in 1909 ^^ and 1910.^° He gave in detail the changes in the outline of the ureter caused by a stone in the lower ureter, and, furthermore, called attention to the value of the method in the diagnosis of certain forms of stricture of the ureter. In 1910 Uhle ^ and his collaborators also described the value of pyelo-ureterography in the diagnosis of ureteral obstruction and lithiasis. In 1911, Oehlecker^^ described the value of pyelography in the identification of certain shadows in the area of the lower ureter. In the same year Dohan ^^ referred to the same method. In 1913 Keene ^^ stated that it had proved to be of greater value in the diagnosis of stone in the lower ureter than the shadowgraph catheter, and then described the resulting ureteral dilatation. In 1912 Furniss ''^ described in detail the diagnosis of certain forms of stricture of the ureter which could be diagnosed in no other way.

Accidents. — The most recent phase of the literature concerning the subject of pyelography deals with the dangers attending its employment. A number of reports were made of lesions found in the kidney after its removal, showing destruction of the renal tissue, evidently by the injected colloidal silver. Thus, in 1911, Zachrisson ^- reported considerable reaction in five days following the injection of colloidal silver, and, on removing the kidney, found that considerable destruction was present and that it was universally studded with black silver deposit. In 1911 Oehlecker,^^ on removing the affected kidney in a case of renal tumor, found the presence of infarcts in the parenchyma stained with colloidal silver. In 1911 Jervell ^^ observed a wedge-shaped area of gangrene in the kidney following pyelography. Ekehorn,-^'' in 1911, found renal edema on operating five days after pyelography. Buerger/^ in 1912, reported deposits of silver in surrounding foci of suppuration in the cortex of the kidney. Blum,^*^ in 1912, reported a series of experiments on the kidney in cadavers, and attacked pyelography on the ground that it is a highly dangerous and, furthermore, useless method in diagnosis. In 1913 the writer ^^ reported three cases operated on for hydronephrosis in which evidence of silver was found in numerous infarcts scattered in the renal parenchyma. He stated that such necrosis of the tissue could follow retention of colloidal silver. If the drainage from the pelvis is blocked, peristalsis may force the retained silver solution into the straight tubules, with resulting necrosis of the tissues.

Tennant," in 1913, reported a case in which the substance of the kidney was damaged by injected colloidal silver. Voelcker,^^ Kelly and Lewis/^ and, later, Vest,^^ reported several cases where evidence of colloidal silver was found at operation in the perirenal tissue. In 1914 Mason ^^ reported two cases where a number of infarcts were found in the kidney following pyelography. Troell,'^'^ in 1913, reported a case in which infiltration of the tissue followed the injection of 6 or 7 c.c. of 7 per cent, solution of colloidal silver in a kidney which was otherwise surgical. Legueu and Papin,*^^ in 1913, described in detail the various types of lesions seen in the kidney following infiltration of the parenchyma with colloidal silver. They ascribe such lesions to overdistention of the pelvis with the hand syringe, and have not observed them since employing the gravity method. In December, 1913, Schwarzwald ^'^ reviewed to date the accidents reported in the literature, of which there were eight. He found that they were all due to error in technic. He also reported a case of a kidney removed for pyelonephritis and multiple abscesses in which a short time before a pyelogram had been made. On examination of the kidney silver was found deposited in the tissues of the diseased portion only. He concludes that the silver particles do not enter via the blood-stream, but probably through the diseased or traumatized tissues. He believes that if the technic is correct, no accidents should follow pyelography. Walker,^'' in July, 1914, gave a detailed resume of the technic involved in pyelography. He claimed that careful injection of the pelvis with hydrostatic pressure will usually obviate any injury to the kidney. He stated that infiltration of the renal substance resulted from excessive pressure, prolonged pressure, . or previous trauma to the pelvis by the catheter. He advised using a small catheter to insure return flow if the pelvis was overdistended.

Fatalities following pyelography have been reported by various observers. In 1911 Roessle" reported a fatahty shortly after pyelography which he believed to be due to colloidal silver poisoning. Evidence of hemorrhagic diathesis appeared following the injection. At postmortem the kidney showed silver substance embedded throughout the tissues. In 1914 Smith ^^ reported a death following pyelography which he attributed to be the direct cause. In 1913 Rosenblatt and Morgandies ^« reported a fatahty some hours following pyelography. The patient died in shock following an injection of 40 c.c. of silver solution. Vest ^s reported a death fourteen days after pyelography which he believed caused hemorrhagic diathesis and possibly death. In 1914 Hofman^' reported a death four days after pyelography which was found to be due to rupture of a hydronephrotic sac. Such an accident is only illustrative of technical error in having used enough pressure to cause rupture, and is not an argument against pyelography. Within the past few months other fatalities have been reported by different American observers. It is of interest to note that in practically every case the solution was injected with the pressure of a hand syringe. The amount injected in most instances was greater than the pelvic capacity.

Within the past year a number of papers have been pubhshed deahng with experimental work on animals in an attempt to discover under what circumstances injuries to the renal substance follow the use of colloidal silver injection.

Tennant," in June, 1913, reported a series of experiments in which he subjected the kidneys of pigs to a varying degree of pressure with colloidal silver solution and noted the results. He found that by introducing the solution at a pressure of over 40 mm. of mercury, infiltration of the kidney invariably resulted.

Strassman,*'^ in January, 1913, reported the effect of overdistention of the renal pelvis in rabbits with colloidal silver under moderate pressure. He found that the silver particles were carried bj^ the lymph-spaces as far as the renal capsule. By the end of twenty-four hours the greater part of the silver had left the renal tissue. He concluded that, with careful technic, taking care not forcibly to distend the pelvis, no injury should follow pyelography.

Wossidlo,^^ in December, 1913, concluded, from a large series of experiments on rabbits, that when the physiologic capacity of the normal pelvis was exceeded by a large amount of colloidal silver solution injected under pressure, the colloidal silver entered the interstitial tissue between the tubules. With hydronephrosis, however, if the pelvic capacity is overfilled, the silver solution entered the renal tissue via the dilated tubules. When a hydronephrosis exists, no more should be injected than the amount first drained away. He claimed, however, that no damage would result if the capacity of the pelvis was not exceeded. He believes that if the pelvis is traumatized, as evidenced by hematuria, colloidal silver should be injected with great precaution, since it can then more easily enter the renal tissue.

Kidd,"° in January, 1914, reported a series of experiments on sheep's kidneys, when he distended the pelvis with silver solution at various pressures. He concluded that the element of time under which the pressure was made was of equal importance with the degree. He claimed that the solution should be injected at a maximum pressure of 60 mm. of mercury, and that it should be exerted less than a minute; when exerted and with greater pressure longer, the silver solution penetrated the renal substance to a varying degree. He believes that the mode of entrance was via the straight tubules.

Rehn,'" in January, 1914, reported similar results following even moderate overdistention of the renal pelvis in rabbits, and believes that great care should be used when colloidal silver is injected into the human kidney.

In May, 1914, Eisendrath '^ reported the results of several experiments on dogs, with similar results. On injecting a dog's renal pelvis with 20 c.c. of 10 per cent, silver solution under pressure of 100 mm., the animal died within five minutes. Necropsy showed quantities of silver deposited in the various organs as the result of widely distributed silver embolism. He believes that this experiment explains the sudden deaths reported in the human. He finds, however, that, as long as only moderate pressure is employed and the capacity is not exceeded, no harm results from injecting the pelvis with silver solution.

It is very evident, therefore, that unless a pyelogram is made with strict technical precautions, it may cause considerable injury. However, in the hands of those familiar with the necessary technic and the selection of cases it has proved to be a comparatively harmless procedure. Thus the writer reported ^^ a series of over 1000 pyelograms made without serious results to any patient. The method is too valuable in the diagnosis of many conditions in the urinary tract to be discarded. EfTort should be made, however, to discover a substance which will not injure the kidney under any circumstances, and which may be safely employed in the hands of those with limited experience.

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