Fol Copyright tJ
'The Tflif.iarr_s
Vlilkin~,
to RE: SEGMENTAL NEPHROGRAM
N. V Raghauaiah J. U rol., 119: 278, 1978
To the Editor. Doctor Raghavaiah claims to have demonstrated a segmental nephrogram in a partial obstruction secondary to a renal calculus. In the radiograms displayed in the article no tomograms or oblique films were shown. Routine tomography frequently obviates the need for vigorous bowel preparation and it is well known that tomography often, in appropriate projections, may show calcifications that cannot be seen on plain films. One wonders whether tomography would have shown the described calculus before the first excretory urogram (IVP). 1 It appears, in fact, that from the submitted radiograms benign peripelvic extravasation of contrast material actually is depicted causing the "fuzzy" density overlying the collecting system in figure 1, A. 2 Oblique films and/or tomograms usually will demonstrate this finding most optimally. In fact, preliminary tomography the day after the IVP may well have shown the dilated collecting system without a need for repeat injection of contrast material. Segmental nephrograms are seen when segmental caliceal obstruction is present secondary to tumors or stones. It is an important concept to emphasize in uroradiography but it is unfortunate that the submitted radiograms do not bear out the intent of the article and that tomography or oblique films were not obtained in the illustrated case. In addition, calcific densities within the collecting system, pelvis and ureter have been demonstrated using modern gray scale ultrasound techniques or even computer tomography in confusing problem cases. Respectfully, Bruce L. McClennan Washington University St. Louis, Missouri 63110 1. Ambos, M. A. and Bosniak, M. A.: Tomography of the kidney bed as an aid in differentiating renal pelvic tumor and stone. Amer. J. Roentgen., 125: 331, 1975. 2. Bernardino, M. E. and McClennan, B. L.: High dose urography: incidence and relationship to spontaneous peripelvic extravasation. Amer. J. Roentgen., 127: 373, 1976. Reply by Author. The intent of my article was to demonstrate a nephrogram involving half of the kidney (segmental nephrogram) owing to acute calculous obstruction of 1 limb of a bifid pelvis. This was demonstrated adequately in figure 1, A, which showed a dense nephrogram involving only the lower half of the kidney and non-visualization of the lower half of the collecting system. It is not a case of peripelvic extravasation of contrast material as described by Doctor Mcclennan for 2 reasons. To diagnose peripelvic extravasation it is essential to visualize the collecting system and the associated peripelvic or pericaliceal extravasation of the contrast material. When the collecting system is not seen, as in the present case, it is difficult to imagine the "fuzzy" density of the extravasated contrast material. Also, there would be no localized, dense nephrogram of the kidney in peripelvic extravasation. This fact would be obvious if we refer to the illustrations published in the article by Bernardino and Mcclennan (reference 2 in the letter). The value of tomography, with or without contrast material, in the diagnosis of calculous disease is well known. Although tomograms and oblique views were obtained in our patient they were not submitted for publication since they did not provide additional information. A good but not vigorous bowel preparation certainly would improve the quality of an IVP, 1 especially in a patient with severe colic who is likely to have mild ileus of the bowel. Although ultrasonography and computer tomography are good non-invasive procedures we do not use them routinely to diagnose renal and ureteral calculi in patients hospitalized with acute renal 387
or ureteral colic. Some believe that sonography has less practical value in demonstrating the stones than do roentgen studies. 2 " A repeat IVP certainly is indicated in these patients, not only for better visualization of the stone but also to assess the level and degree of obstruction in the collecting system and to monitor the progression of the stone. This information is essential to plan the treatment of a patient with acute colic associated with urinary calculus disease. 1. Marshall, V. F.: The controversial history of excretory urography. In: Clinical Urography, 4th ed. Edited by J. L. Emmett and D. M. Witten. Philadelphia: W. B. Saunders Co., pp. 2-5, 1977. 2. Becker, J. A. and Staiano, S.: Milk of calcium in a renal cyst. A sonolucent mass effect. J. Clin. Ultrasound, 3: 135, 1975. 3. Becker, J. A. and Schnieder, M.: Retroperitoneum. In: Clinical Urognphy, 4th ed. Edited by J. L. Emmett and D. M. Witten. Philadelphia: W. B. Saunders Co., pp. 214-338, 1977. PERCUTANEOUS NEPHROSTOMY
To the Editor. Much has been written regarding the efficacy of percutaneous nephrostomy for short-term urinary diversion. Most authors offhandedly remark that the tracts can be dilated easily and large catheters can be positioned for more or less permanent diversion. However, few authors indicate the true difficulties involved in this substitution. One author suggests the use of polytetrafluoroethylene dilators made to specification by the Cook Company* before the introduction of a 12F Ingraham balloon catheter. t· 1 In the absence of these specific polytetrafluoroethylene dilators may I suggest 3 procedures that will help the clinician convert to permanent drainage. Dilators can be fashioned from woven urethral followers by merely cutting off the metal tip, briefly exposing the catheter to a low heat flame and then perforating the tip with an 18 gauge needle while it is still warm. Dilators can be made in any desired size. It is much easier to pass the catheter if it has been prestiffened by immersing it in sterile ice for several minutes. This is the same principle used in facilitating the passage of nasogastric tubes. In our hospital the operating room provides ice for renal operations. The catheter will be made rigid by the ice for about 60 seconds. Additional stiffness can be imparted to the catheter by using a translumbar aortography arch needle as a stent long enough to pass through the fascia.* The catheter must be loaded onto the translumbar aortography needle, which is then passed over the guide wire. This needle will fit inside the catheter if the end hole is enlarged slightly. We hope that these suggestions will enable others to progress more easily from a temporary percutaneous nephrostomy to a more permanent one. Respectfully, Walter L. Gerber, Robert C. Brown and Bill Barnhart University of Iowa Hospitals and Clinics Iowa City, Iowa 52242 l. Staples, D. P., Ginsberg, N. J. and Johnson, M. L.: Percuta-
neous nephrostomy: a series and review of the literature. Amer. J. Roentgen., 130: 75, 1978. * Cook Co., P.O. Box 489, 925 S. Curry Pike, Bloomington, Indiana 47401. t Argyle Co., Sherwood Medical Industries, Inc., 1831 Olive St., St. Louis, Missouri 63103.
RE: UROLOGIC COMPLICATIONS OF PELVIC IRRADIATION
Richard J. Dean and Bernard Lytton J. Urol., 119: 64, 1978 To the Editor. This article serves an important purpose in reminding clinicians of the significant, albeit frequently distantly removed,
'The Tflif.iarr_s
Vlilkin~,
to RE: SEGMENTAL NEPHROGRAM
N. V Raghauaiah J. U rol., 119: 278, 1978
To the Editor. Doctor Raghavaiah claims to have demonstrated a segmental nephrogram in a partial obstruction secondary to a renal calculus. In the radiograms displayed in the article no tomograms or oblique films were shown. Routine tomography frequently obviates the need for vigorous bowel preparation and it is well known that tomography often, in appropriate projections, may show calcifications that cannot be seen on plain films. One wonders whether tomography would have shown the described calculus before the first excretory urogram (IVP). 1 It appears, in fact, that from the submitted radiograms benign peripelvic extravasation of contrast material actually is depicted causing the "fuzzy" density overlying the collecting system in figure 1, A. 2 Oblique films and/or tomograms usually will demonstrate this finding most optimally. In fact, preliminary tomography the day after the IVP may well have shown the dilated collecting system without a need for repeat injection of contrast material. Segmental nephrograms are seen when segmental caliceal obstruction is present secondary to tumors or stones. It is an important concept to emphasize in uroradiography but it is unfortunate that the submitted radiograms do not bear out the intent of the article and that tomography or oblique films were not obtained in the illustrated case. In addition, calcific densities within the collecting system, pelvis and ureter have been demonstrated using modern gray scale ultrasound techniques or even computer tomography in confusing problem cases. Respectfully, Bruce L. McClennan Washington University St. Louis, Missouri 63110 1. Ambos, M. A. and Bosniak, M. A.: Tomography of the kidney bed as an aid in differentiating renal pelvic tumor and stone. Amer. J. Roentgen., 125: 331, 1975. 2. Bernardino, M. E. and McClennan, B. L.: High dose urography: incidence and relationship to spontaneous peripelvic extravasation. Amer. J. Roentgen., 127: 373, 1976. Reply by Author. The intent of my article was to demonstrate a nephrogram involving half of the kidney (segmental nephrogram) owing to acute calculous obstruction of 1 limb of a bifid pelvis. This was demonstrated adequately in figure 1, A, which showed a dense nephrogram involving only the lower half of the kidney and non-visualization of the lower half of the collecting system. It is not a case of peripelvic extravasation of contrast material as described by Doctor Mcclennan for 2 reasons. To diagnose peripelvic extravasation it is essential to visualize the collecting system and the associated peripelvic or pericaliceal extravasation of the contrast material. When the collecting system is not seen, as in the present case, it is difficult to imagine the "fuzzy" density of the extravasated contrast material. Also, there would be no localized, dense nephrogram of the kidney in peripelvic extravasation. This fact would be obvious if we refer to the illustrations published in the article by Bernardino and Mcclennan (reference 2 in the letter). The value of tomography, with or without contrast material, in the diagnosis of calculous disease is well known. Although tomograms and oblique views were obtained in our patient they were not submitted for publication since they did not provide additional information. A good but not vigorous bowel preparation certainly would improve the quality of an IVP, 1 especially in a patient with severe colic who is likely to have mild ileus of the bowel. Although ultrasonography and computer tomography are good non-invasive procedures we do not use them routinely to diagnose renal and ureteral calculi in patients hospitalized with acute renal 387
or ureteral colic. Some believe that sonography has less practical value in demonstrating the stones than do roentgen studies. 2 " A repeat IVP certainly is indicated in these patients, not only for better visualization of the stone but also to assess the level and degree of obstruction in the collecting system and to monitor the progression of the stone. This information is essential to plan the treatment of a patient with acute colic associated with urinary calculus disease. 1. Marshall, V. F.: The controversial history of excretory urography. In: Clinical Urography, 4th ed. Edited by J. L. Emmett and D. M. Witten. Philadelphia: W. B. Saunders Co., pp. 2-5, 1977. 2. Becker, J. A. and Staiano, S.: Milk of calcium in a renal cyst. A sonolucent mass effect. J. Clin. Ultrasound, 3: 135, 1975. 3. Becker, J. A. and Schnieder, M.: Retroperitoneum. In: Clinical Urognphy, 4th ed. Edited by J. L. Emmett and D. M. Witten. Philadelphia: W. B. Saunders Co., pp. 214-338, 1977. PERCUTANEOUS NEPHROSTOMY
To the Editor. Much has been written regarding the efficacy of percutaneous nephrostomy for short-term urinary diversion. Most authors offhandedly remark that the tracts can be dilated easily and large catheters can be positioned for more or less permanent diversion. However, few authors indicate the true difficulties involved in this substitution. One author suggests the use of polytetrafluoroethylene dilators made to specification by the Cook Company* before the introduction of a 12F Ingraham balloon catheter. t· 1 In the absence of these specific polytetrafluoroethylene dilators may I suggest 3 procedures that will help the clinician convert to permanent drainage. Dilators can be fashioned from woven urethral followers by merely cutting off the metal tip, briefly exposing the catheter to a low heat flame and then perforating the tip with an 18 gauge needle while it is still warm. Dilators can be made in any desired size. It is much easier to pass the catheter if it has been prestiffened by immersing it in sterile ice for several minutes. This is the same principle used in facilitating the passage of nasogastric tubes. In our hospital the operating room provides ice for renal operations. The catheter will be made rigid by the ice for about 60 seconds. Additional stiffness can be imparted to the catheter by using a translumbar aortography arch needle as a stent long enough to pass through the fascia.* The catheter must be loaded onto the translumbar aortography needle, which is then passed over the guide wire. This needle will fit inside the catheter if the end hole is enlarged slightly. We hope that these suggestions will enable others to progress more easily from a temporary percutaneous nephrostomy to a more permanent one. Respectfully, Walter L. Gerber, Robert C. Brown and Bill Barnhart University of Iowa Hospitals and Clinics Iowa City, Iowa 52242 l. Staples, D. P., Ginsberg, N. J. and Johnson, M. L.: Percuta-
neous nephrostomy: a series and review of the literature. Amer. J. Roentgen., 130: 75, 1978. * Cook Co., P.O. Box 489, 925 S. Curry Pike, Bloomington, Indiana 47401. t Argyle Co., Sherwood Medical Industries, Inc., 1831 Olive St., St. Louis, Missouri 63103.
RE: UROLOGIC COMPLICATIONS OF PELVIC IRRADIATION
Richard J. Dean and Bernard Lytton J. Urol., 119: 64, 1978 To the Editor. This article serves an important purpose in reminding clinicians of the significant, albeit frequently distantly removed,
