MODIFIED ANATROPHIC NEPHROLITHOTOMY FOR MANAGEMENT OF STAGHORN CALCULI: IS RENAL FUNCTION PRESERVED?

0022-5347/99/1623-0670/0 THEJOLWAL OF UROLOGY Copyright 0 1999 by AMERICAN U R O ~ I CASS~CUTION, AL INC

Vol. 162,670-673, September 1999 Printed in U.S.A.

MODIFIED ANATROPHIC NEPHROLITHOTOMY FOR MANAGEMENT OF STAGHORN CALCULI: IS RENAL FUNCTION PRESERVED? ALLEN F. MOREY,* KENNETH S. NITAHARA

AND

JACK W. McANINCHI,S

From the Department of Urology, University of California School of Medicine and Sun Francisco General Hospital, Sun Francisco, California

ABSTRACT

Purpose: We report the results of modified anatrophic nephrolithotomy in select patients with complex staghorn calculi. Materials and Methods: From 1987 to 1997 modified anatrophic nephrolithotomy, including 1 bilateral procedure, was performed in 15 patients at San Francisco General Hospital. Preoperative imaging included excretory urography, sonography and computerized tomography. Preoperative and postoperative quantitative renal function was assessed with 99"technetium dimercapto-succinic acid renal scintigraphy and serum creatinine measurements. Results: Mean patient age was 42 years and 11 of the 15 patients were male. Bilateral nephrolithotomy was performed in 1 patient on separate occasions. Average surgical time was 3.7 hours with blood loss of 325 ml. Length of hospital stay averaged 4 days. Residual stones were present after 3 procedures, and 1 of these patients required a secondary procedure. There were no other short-term complications. Renal function was not significantly altered. Conclusions: Modified anatrophic nephrolithotomy for staghorn renal stones rendered most patients stone-free with concomitant preservation of renal function. Because of its safety, efficacy and simplicity we believe that continued use of this procedure is warranted in select patients with complex renal stone disease. KEYWORDS:kidney calculi, kidney

The management of staghorn calculi continues to evolve. Until the 1970s conservative management predominated.' Now most favor aggressive surgical management to preserve renal function better and t o decrease m~rtality.'.~Smith and Boyce first popularized anatrophic nephrolithotomy in 196fL4. Their technique afforded the advantages of complete stone removal and concomitant formal renal reconstruction. However, since the mid 1980s less invasive treatments have become increasingly Advances, such as extracorporeal shock wave lithotripsy, percutaneous nephrolithotripsy and ureteroscopic lithotripsy, have decreased the perioperative morbidity and postoperative convalescence for As a result, endourologipatients with staghorn stones.". cal treatments have almost completely replaced open nephrolithotomy in contemporary management. Because complex, high volume renal calculi frequently mandate multiple endourological procedures, we have selectively used a modification of the original anatrophic nephrolithotomy described by Smith and B ~ y c eWe . ~ present our technique and results.

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endoscopic or extracorporeal treatment (fig. 1). Partial staghorn calculi were not included in this series. Stone and renal anatomy was routinely evaluated with plain radiography and contrast excretory urography. Occasionally, renal sonography and computerized tomography were substituted or added. Renal function before and after surgery (4 to 6 weeks) was measured quantitatively by serum creatinine levels and 99"technetium dimercapto-succinic acid (DMSA) renal scintigraphy. With the patient in the lateral decubitus position the kidney is exposed through an extraperitoneal flank incision. The renal artery and vein are isolated with nonocclusive elastic vessel loops. The proximal ureter is occluded with an elas-

PATIENTS AND METHODS

From 1987 to 1997, 16 anatrophic nephrolithotomies were performed in 15 patients (11 male) at San Francisco General Hospital. Bilateral nephrolithotomy was performed in 1 patient on 2 separate occasions. Patient age ranged from 7 to 65 years (mean 42). All patients had high volume renal stones deemed too complex for any combination of percutaneous, Accepted for publication March 5, 1999. Presented at annual meeting of American Urological Association,

San Diego, California, May 30-June 4, 1998.

*Current address: Urology Service, Brooke Army Medical Center, Sa,n Antonio, Texas 78234. I Requests for reprints: 1001 Potrero Ave., Room 3A18, San Francisco, California 94110. FIG. 1. Preoperative scout film in woman with complex renal cal$Financial interest and/or other relationship with Bayer Pharma- culi. After bilateral nephrolithotomy patient was stone-free except ceutical. for 5 mm. fragment extracted via elective right ureteroscopy. 670

MODIFIED ANATROPHIC NEPHROLITHOTOMY FOR STAGHORN CALCULI

tic loop to prevent distal migration of small stone fragments. The kidney is completely mobilized on all surfaces to expose the entire renal capsule. After intravenous administration of 12.5 gm. mannitol the renal artery is occluded with a Rommel tourniquet and the renal surface is inspected for uniform loss of arterial blood flow. Occasionally, multiple renal arteries exist, all of which must be occluded. If incomplete ischemia is suspected, the renal hilum is inspected for additional arterial branches. The kidney is cooled with ice slush for 10 minutes before nephrotomy, and ice slush is added periodically throughout the procedure to ensure continuous cooling. The renal capsule is carefully incised over its entire lateral Convex surface longitudinally and the posterior half is fully mobilized off of the underlying parenchyma. A parallel parenchymal incision is made l to 2 cm. posterior to the lateral capsulotomy, directly into the posterior calices. The palpable stone burden often directs the exact location and angle of the parenchymal incision (fig. 2). After opening the collecting system and exposing the stone, brain retractors are used to separate the deep renal parenchyma. The epithelial surface is mobilized from the stone with nerve hooks carefully to avoid fracture. Stone removal is guided by bimanual examination of the bivalve kidney to assess for possible additional caliceal stones (fig. 2). Intraoperative renal sonography and flexible endoscopy are used to inspect the pelvicaliceal anatomy further and ensure stonefree status. After stone removal is complete, careful hemostasis is achieved by ligating segmental renal vessels individually with 4-zero chromic suture. After the Rommel tourniquet is released from the renal artery, further bleeders are similarly controlled. The renal parenchyma is then coapted without suture closure of the collecting system, and the capsule is unrolled and closed in a watertight fashion with 3-zero polyglactin suture (fig. 3). This technique reconstitutes and closes the parenchymal incision least invasively. Formal collecting system closure, nephrostomy tubes and internalized stents are not necessary. A Penrose drain is left in place for 24 to 48 hours until drainage is minimal. Patients are kept at bed rest for about 48 hours until the urine clears. RESULTS

Estimated blood loss was 325 ml. (range 200 to 700)for the 16 procedures. Cold renal ischemia time was generally about 45 minutes. Transfusion was required in 2 patients, with 2 units of packed red blood cells in 1 and 1unit in the other. The duration of surgery was 3.7 hours (range 2 to 6). Perioperative complicatisnk were negligible. Average length of hospital stay was 4 days (range 2 to 7), in most cases reflect-

67 1

FIG. 3. Renal reconstruction is accomplished by running closure of renal capsule alone. Underlying parenchymal incision is denoted by forceps just posterior to capsular closure.

ing the time to return of bowel function, ambulation and pain control. Stone analysis revealed 9 struvite, 3 calcium oxalate, 2 calcium phosphate and 2 uric acid calculi. Stone-free status was attained in 13 of 16 procedures (81%) and no patient suffered major morbidity. In 2 patients several asymptomatic peripheral 2 to 3 mm. stones remained after removal of innumerable small stones. In another patient a single 5 mm. stone fragment was identified in the distal ureter on a postoperative plain film, and uneventful elective ureteroscopic stone extraction was performed several weeks later. All patients underwent followup for postoperative renal function a t 4 to 6 weeks. Overall, serum creatinine levels increased from 1.1to 1.2 mg./dl. (normal 0.6 to 1.4). In 13 cases nuclear renography with DMSA revealed a slight decrease in ipsilateral function from an average of 4 2 8 before to 38% after nephrolithotomy. Renal function actually increased from about 40 to 42%in 3 cases (fig. 4). DISCUSSION

These data suggest that modified anatrophic nephrolithotomy is safe and effective for single stage management of complex renal stone disease. Our procedure differs from that described by Smith and Boyce4 in 1968 and Boyce and Elkins5 in 1972 in that we incorporated several major modifications to reduce operating and anesthesia time without increasing morbidity. In their classic description Smith and Boyce identified the boundary of the segmental renal blood supply by clamping the posterior arterial branch and injecting methylene blue. In our modification the parenchyma is

FIG. 2. A, posterior renal capsule is completely reflected. B, parenchymal incision is made about 2 cm. posterior to capsular b5sion and directedOnto palpable stone burden.

Intraoperative renal ultrasonography was helpful in identifying retained stone fragments. It is important to remember 42.03% that air pockets within the bivalve kidney cause acoustic 37.94% shadowing, which may mimic calculi. In our hands intraoperative radiographs obtained with the patient in the flank position have been unwieldy and of poor quality. What is the role of anatrophic nephrolithotomy in the age of endourology? Clearly percutaneous nephrolithotomy is appropriate for most medium and large renal calculi. Snyder and Smith, comparing percutaneous extraction with anatrophic nephrolithotomy for staghorn stones, reported decreased overall surgical time, transfusion rate and hospital charges among percutaneously treated patients.' In addition, the time required for patients to resume normal daily activity was nearly 4 times longer for those who had undergone anatrophic nephrolithotomy. However, high volume stone burden and moderate or high grade pelvicaliceal dilaPost-op Pre-op tation have been associated with ancillary procedures, longer FIG. 4. Overall ipsilateral renal function before and afier modified hospitalizations and higher hospital bills when treated peranatrophic nephrolithotomy as assessed by 99"'technetium DMSA c u t a n e o ~ s l y . Combination ~ therapy with extracorporeal renal scintigraphy (16 procedures in 15 patients). shock wave lithotripsy and nephrolithotomy has been associated with residual stone rates as high as 50 to 75%." routinely incised 1 to 2 cm. posterior to the lateral surface, directly over the palpable stone burden, without preliminary CONCLUSIONS segmental vascular dissection.4 As we observed only a small We believe that anatrophic nephrolithotomy is suitable for decrease in relative function, we conclude that the additional patients with complex stone disease and/or complex intraretime to determine the exact limit of the segmental blood nal anatomy, and for those in whom body habitus or the need supply is not justified. Furthermore, because extensive disfor concomitant renal reconstruction might contraindicate section of the renal artery and its branches is avoided, the endourological techniques. We agree with others that it is risk of arterial vasospasm is minimized." reasonable t o offer open nephrolithotomy as first line therapy Boyce and Elkins emphasized the importance of routine for patients with complete staghorn calculi, infundibular steinfundibular reconstruction and formal closure of the entire nosis a n d o r extreme dilatation of the collecting system.'l collecting ~ y s t e m Our . ~ modification is similar to that reModified anatrophic nephrolithotomy has had a peripheral ported by Redman et al in that the infundibuli are not routinely reconstructed.~~However, our simplified method of but important role a t San Francisco General Hospital for more than 10 years. Our modifications simplify the procerenal reconstruction after nephrolithotomy is unique in that dure and facilitate excellent results with limited morbidity. it is based solely on the posterior renal capsule flap, which This procedure can be an appropriate sing1e stage treatment has proved extremely reliable in this patient popu~ation~ Despite the presence of acute and chronic inflammation in option for select patients with advanced renal calculous disease. most cases, the capsule was not noted to be flimsy, scarred or adherent to the underlying parenchyma. By separating the REFERENCES capsular and parenchymal incisions by several centimeters, overlapping suture lines are avoided, thus ensuring a water1. Libertino, J. A,, Newman, H. R., Lytton, B. and Weiss, R. M.: tight renal closure. None of our patients had prolonged PenStaghorn calculi in solitary kidneys. J. Urol., 105 753, 1971. 2. Gupta, M., Bolton, D. M., Gupta, P. N. and Stoller, M. L.: Imrose drainage, even without internal or external urinary proved renal function following aggressive treatment of urolidiversion. thiasis and concurrent mild to moderate renal insufficiency. Nephron injury during anatrophic nephrolithotomy apJ. Urol., 152 1086, 1994. pears to be minimal based on nuclear renography and serum 3. Koga, S., Arakaki, Y., Matsuoka, M. and Ohyama, C.: Staghorn creatinine measurements. Although followup is short, we do calculi-long term results of management. Brit. J. Urol., 68: not expect delayed additional reduction in function. Our se122,1991. ries is small but the largest in more than 10 Years and among 4. Smith, M. J. V. and Boyce, w. H.: Anatrophic nephrotomy and the few to assess the impact of nephrolithotomy on renal plastic calyrhaphy. J. Urol., 9 9 521, 1968. function quantitatively with nuclear scintigraphy. Our find5. Boyce, W. H. and Elkins, I. B.: Reconstructive renal surgery following anatrophic nephrolithotomy: followup of 100 consecings appear to approximate those of Smith and Boyce? who utive cases. J. Urol., 111: 307, 1974. in 1968 qualitatively described relative renal function in 36 6. Snyder, J. A. and Smith, A. D.: Staghorn calculi: percutaneous of 138 patients (26%)and noted improvement in 12 (33%),no extraction versus anatrophic nephrolithotomy. J. Urol., 136 change in 22 (61%)and a decrease in 2 (6%).Others have 351, 1986. documented similar results.'2-'8 7. Lange, P. H., Reddy, P. K., Hulbert, J. C., Clayman, R. V., Our patients may not be directly comparable to those in Castaneda-Zuniga,W. R., Miller, R. P., Coleman, C. C. and previous reports. During the time frame of this series, which Amplatz, K.: Percutaneous removal of caliceal and other "inbegan in 1987, endourological management was the primary accessible" stones: instruments and techniques. J. Urol., 132: approach a t our institution for the vast majority of renal 439, 1984. 8. Reddy, P. K., Lange, P. H., Hulbert, J. C., Clayman, R. V., Breen, stones. Patients included in this series were a select group J. F., Hunter, D. H., Coleman, C. C., Castaneda-Zuniga,W. R. with extremely large andor complex stones. Previous series and Amplatz, K.: Percutaneous removal of caliceal and other from the 1960s and 1970s may have included patients with "inaccessible" stones: results. J. Urol., 132: 443, 1984. less complex stones, since minimally invasive interventions 9. Assimos, D. G., Wrenn, J. J., Harrison, L. H., McCullough,D. L.1 were not then available for small and midsize renal stones. Boyce, W. H., Taylor, C. L., Zagoria, R. J. and Dyer, R. B.: A Regardless, our residual stone rate was similar to that recomparison of anatrophic nephrolithotomy and percutaneous ported historically." 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MODIFIED ANATROPHIC NEPHROLITHOTOMY FOR STAGHORN CALCULI 10. Teichman, J. M. H., Long, R. D. and Hulbert, J. C.: Long-term renal fate and prognosis after staghorn calculus management. J. Urol., 153 1403,1995. 11. Chandhoke, P. S.:Cost-effectiveness of different treatment options for staghorn calculi. J. Urol., 156 1567,1996. 12. Redman, J. F., Bissada, N. K. and Harper, D. L.: Anatrophic nephrolithotomy: experience with a simplification of the Smith and Boyce technique. J. Urol., 122 595, 1979. 13. Thomas, R., Lewis, R. W. and Roberts, J. A.: The renal quantitative scintillation camera study for determination of renal function after anatrophic nephrolithotomy. J. Urol., 125 287, 1981. 14. Namiki, M., Itoh, H., Yoshioka, T. and Itatani, M.: Modified anatrophic nephrolithotomy. Urology, 21: 265,1983. 15. Belis, J. A., Morabito, R. A., Kandzari, S. J., Lai, J. C. W. and Gabriele, 0. F.: Anatrophic nephrolithotomy: preservation of renal function demonstrated by differential quantitative radionuclide renal scans. J. Urol., 125 761, 1981. 16. Stage, K.H. and Lewis, S.: Pre- and postoperative evaluation of renal function in patients with staghorn calculi utilizing quantitative renal scanning. Urology, 17: 29, 1981. 17. Kawamura, J., Itoh, H., Okada, Y.,Higashi, Y., Yoshida, O., Fujita, T. and Torizuka, K.: Preoperative and postoperative cortical function of the kidney with staghorn calculi assessed by 99%chnetium-dimercaptosuccinicacid renal scintigraphy. J. Urol., 130: 430,1983. 18. Stubbs, A. J., Resnick, M. I. and Boyce, W. H.: Anatrophic nephrolithotomy in the solitary kidney. J. Urol., 119 457, 1978. 19. Segura, J. W., Preminger, G. M., Assimos, D. G., Dretler, S. P., Kahn, R. I., Lingeman, J. E., Macaluso, J. N., Jr. and McCullough, D. L.: Nephrolithiasis clinical guidelines panel summary report on the management of staghorn calculi. J. Urol., 151: 1648, 1994. 20. Segura, J. W.: The role of percutaneous surgery in renal and ureteral stone removal. J. Urol., 141: 780,1989. 21. Paik, M. L.,Wainstein, M. A., Spirnak, J. P., Hampel, M. and Resnick, M. I.: Current indications for open stone surgery in the treatment of renal and ureteral calculi. J. Urol., 159 374, 1998.

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EDITORIAL COMMENT The term anatrophic in conjunction with nephrolithotomy was coined by Smith and Boyce (reference 4 in article) when initially describing an operative procedure that consists of incising the renal parenchyma to remove large complex renal calculi. The parenchymal incision was made along the “avascular“ plane of the kidney between the anterior and posterior vascular segments. Because an incision along this plane does not interrupt the arterial blood supply to any portion of the kidney, it does not result in atrophy of any of the renal segments and, therefore, was termed anatrophic. In that the authors fail to identify the vascular planes as originally described by Boyce it is likely that renal tissue was damaged and a purist may argue whether the procedure they describe is truly anatrophic. The authors do note a small decrease in relative function and the significance of this observation could certainly be debated. The modification using the renal capsule to cover the renal parenchymal incision so that overlapping suture lines are avoided appears to be of value. This procedure follows the principles as advocated by Smith and Boyce by avoiding deep sutures within the renal parenchyma which likely result in tissue necrosis. As a student of Boyce, I continue to believe that reconstruction of the collecting system is an important component of the procedure and for this reason my experience varies with that of the authors. Often infundibular stenosis and caliceal obstruction occur due to the presence of a stone and chronic infection. By opening these structures and re-epithelializing the collecting system re-stenosis, infection and recurrent stone formation are believed to be reduced. The long-term experience of Smith and Boyce certainly demonstrates the success of this approach. I continue to believe that open stone surgery has a role in the management of large, complex renal stones, and anatrophic nephrolithotomy continues to have an important role in the management of these calculi. The modification of the authors is a welcome addition to a procedure whose value has withstood the test of time. Martin I. Resnick Department of Urology Case Western Reserve University Cleveland, Ohio