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The Renal Quantitative Scintillation Camera Study for Renal Determiantion of Renal Function after Anatrophic Nephrolithotomy
0022··Z:3t.~7 /8l/l2E2--02S7$02,00/0 Vol. 125, l\1arch
THE e..TO-URNAL OF UROLOGY
CopyTight © 1981 by The VVilliaDJ.s & 1_1,/ilki:n.s Co.
Printed
U.S.A.
TI-IE RENAL TIVE SCINTILLATION CAMERA STUDY FOR DETERMINATION OF RENAL FUNCTION AFTER ANATROPHIC NEPHROLITHOTOMY RAJU THOMAS, RONALD W. LEWIS AND JAMES A. ROBERTS From the Department of Urology, Tulane University, New Orleans, Louisiana
ABSTRACT
The effect of hypothermic anatrophic nephrolithotomy was evaluated in 13 patients by comparing preoperative and postoperative renal quantitative scintillation camera studies. Total renal function as measured by effective renal plasma flow remained normal postoperatively. However, the operated kidney had a significant loss of function with a proportionate compensatory hypertrophy of the contralateral kidney. This finding explains the normal total renal function, the good end result of the operation being stable renal function if stones do not recur. Management of staghorn calculi of the kidney always has been a challenge to the urologic surgeon. There have been advocates of a conservative (that is medical treatment) as well as a more aggressive (operative) approach to staghorn calculi. In 1971 Libertino and associates reported their experience with 17 patients and concluded that medical treatment was the choice for asymptomatic staghom calculi. 1 More recently, others have shown the deleterious effect of the unoperated staghorn calculus and have advocated an operative approach. 2- 5 Of the operative techniques hypothermic anatrophic nephrolithotomy has been shown to be an effective method of surgically dealing with the staghom calculus. 4 - 6 Using serum creatinine and creatinine clearance values in 30 solitary kidneys, Stubbs and associates have shown that no statistically significant difference was found between the average preoperative and postoperative renal function values. 6 Boyce and Elkins evaluated renal function by blood urea nitrogen (BUN) only and reported that renal function had improved or remained stable postoperatively in aJl but 2 of 100 consecutive cases of an.atrophic nephrolithotomy. 4 Wickham and associates similarly have reported some improvement of serum creatinine and creatinine clearance levels in 100 cases of nephrolithotomy under hypothermia. 7 However, there have been no reports that provide any details as far as individual renal function is concerned. 1- 5 No study has been done on the effect of c.n-,h·on nephrolithotomy on the individual function of either the involved or the uninvolved kidney. We herein have used renal nt,,t,,trn .. scintillation gamma camera studies to evaluate and total renal function. These studies were obtained rn,,arn.-,cn·<> t iu,,lu and compared to those done oo,st,:,p,ers determine the effect of hypotherm1c n:.ofn\rm on individual as weJ.I as total renal ru11ctrn,1.
plasma flow with this technique has been shown to be an accurate indicator of renal function. 8 The standard hypothermic anatrophic nephrolithotomy as described initially by Smith and Boyce in 1968 was done. 5 Most of these procedurns were done by a resident under the direct supervision of faculty members. The average ischemia time was 74 minutes. The average blood loss was 1.3 units (675 cc) and an average of l.l units (542 cc) of blood was replaced. Postoperative BUN, creatinine and renal quantitative scintillation camera studies were done with an average interval between the operative procedure and the postoperative renal scan of 13.6 months. BUN and creatinine values were not available for 1 of the 13 patients. Statistical analysis was done using Student's paired t test. RESULTS
Preoperative and postoperative BUN and creatinine values are presented in table l. No statistical difference was found during this time. The preoperative and postoperative effective renal plasma flow (total as well as individual kidney) values ru:e presented in table 2. The total renal function as measured by the total effective renal plasma flow was slightly decreased (from 591 to 545 ml. per minute per 1.73 M. 2 ), which was of no statistical significance. However, the effective renal plasma flow to the operated side showed a significant postoperative decrease (from 258 to 182 ml. per minute per 1.73 M.2, p <0.01). At the same tin1e the non-operated kidney showed a mean increase in effective renal plasma flow (from 321 to 362 mL per minute per L73 M. 2 ). DISCUSSION
~~.VH~V•~UC.J
METHODS
Of 35 patients treated with various modalities for staghorn calculi 13 who underwent hypothermic anatrophic nephrolithotomy for a unilateral staghom calculus were selected for study. No disease or abnormality was found in the contralateral kidney and, thus, it acted as a control. Each of these 35 patients had preoperative evaluation with BUN, creatinine and the renal quantitative scintillation camera study using 131iodine hippuran. Determination of effective renal Accepted for publication June 27, 1980. Read at annual meeting of Southeastern Section, American Urological Association, San Juan, Puerto Rico, March 23-27, 1980. Supported by United States Public Health Service Grant 5 T32 AM07212. 287
If we had used the usual parameters of evaluating the postoperative renal function (BUN and creatinine), as was done in the past, we would have concluded that renal function had remained stable or unchanged. In addition, the renal quantitative scintillation camera study showed that total renal function remained unchanged. However, on comparing individual renal function we have found that the operated kidney does have a significant loss of function, while the contralateral kidney has a proportionate compensatory hypertrophy. The emerging consensus is that hypothermic anatrophic nephrolithotomy is an effective method to manage surgically staghorn calculus disease. The effect of this procedure on renal function has remained controversial. Various reports have found stable or improved renal function postoperatively. 3 • 4 • 6• 7 Gil-Vernet has maintained that this procedure compromises renal function. 9 We believe that BUN, creatinine and creatinine
288
THOMAS, LEWIS AND ROBERTS
clearance are not adequate to evaluate accurately the effect of this procedure. The renal quantitative scintillation camera study is an excellent method to determine individual and total renal function as 1. Comparison of preoperative and postoperative studies in patients with unilateral staghorn calculus and anatrophic nephrolithotomy
TABLE
BUN (mg./ml.)
Pt. No. 1 2 3 4 5 6 7 8 9 10 11 12
Creatinine (mg./ml.)
Preop.
Postop.
Preop.
Postop.
12 9 16 15
18 10 10 17 30 10
LO 0.7 L2 1.1 L4 LO L2 1.1 LO L2 0.8 L5
1.1 0.8
16
15 11 12 16 13 19 24
10 11 19 14 23
L2 L6 0.9 LO 0.5 L2 L4 0.8 L3
No statistical differences by Student's paired t test. TABLE
2. Preoperative and postoperative effective renal plasma flow (ml. per minute per 1. 73 M. 2)
Pt. No.
Side
Preop.
Postop.
Total effective renal plasma fiow * 1 662 721 2 670 558 537 3 521 398 4 467 488 5 375 524 401 6 696 7 575 629 586 8 9 689 698 659 659 10 523 502 11 12 623 583 590 435 13 Mean 591 545 Individual effective renal plasma fiow-operated sidet 1 Rt. 333 299 Rt. 2 278 187 3 Rt. 276 201 4 Lt. 211 185 5 Lt. 101 73 6 Lt. 231 146 Lt. 397 164 7 8 Lt. 254 87 Lt. 9 323 290 10 Lt. 269 139 11 Rt. 248 196 Lt. 12 210 239 Lt. 227 161 13 Mean 258 182 Individual effective renal plasma fiow-non-operated side* 1 Lt. 328 421 Lt. 2 371 392 Lt. 261 3 319 281 4 Rt. 186 5 Rt. 302 387 254 Rt. 6 292 411 Rt. 7 298 499 Rt. 8 374 408 9 Rt. 365 Rt. 519 10 389 Lt. 275 11 305 Rt. 12 260 344 274 Rt. 362 13 362 Mean 321
*No statistical differences by Student's paired t test.
t Significant statistical differences by Student's paired t test (p <0.01).
determined by the individual and total effective renal plasma flow. This valuable diagnostic tool has helped us in determining that the kidney undergoing hypothermic anatrophic nephrolithotomy does have a significant decrease in function, which almost always is compensated adequately by hypertrophy of the contralateral kidney, thereby maintaining stable total renal function. Therefore, we agree that total renal function remains normal. Thus, despite some loss of renal function from the operation, as we have shown, progressive loss is prevented by anatrophic nephrolithotomy as opposed to no operative treatment. This finding was consistent in our patients with a unilateral staghorn calculus who underwent anatrophic nephrolithotomy. We favor an aggressive operative approach for staghorn calculus disease and believe that hypothermic anatrophic nephrolithotomy is a good operative approach to the management of this disease entity. REFERENCES
1. Libertino, J. A., Newman, H. R., Lytton, B. and Weiss, R. M.: Staghom calculi in solitary kidneys. J. Urol., 105: 753, 1971. 2. Singh, M., Chapman, R., Tresidder, G. C. and Blandy, J.: The fate of the unoperated staghom calculus. Brit. J. Urol., 45: 581, 1973. 3. Blandy, J. P. and Singh, M.: The case for a more aggressive approach to staghorn stones. J. Urol., 115: 505, 1976. 4. Boyce, W. H. and Elkins, I. B.: Reconstructive renal surgery following anatrophic nephrolithotomy: followup of 100 consecutive cases. J. Urol., 111: 307, 1974. 5. Smith, M. J. V. and Boyce, W. H.: Anatrophic nephrotomy and plastic calyrhaphy. J. Urol., 99: 521, 1968. 6. Stubbs, A. J., Resnick, M. I. and Boyce, W. H.: Anatrophic nephrolithotomy in the solitary kidney. J. Urol., 119: 457, 1978. 7. Wickham, J.E. A., Coe, N. and Ward, J.P.: One hundred cases of nephrolithotomy under hypothermia. J. Urol., 112: 702, 1974. 8. Schlegel, J. U. and Hamway, S. A.: Individual renal plasma flow determination in 2 minutes. J. Urol., 116: 282, 1976. 9. Gil-Vernet, J.: New surgical concepts in removing renal calculi. Urol. Int., 20: 255, 1965.
EDITORIAL COMMENT There are so many variables in individual patients and in surgical procedures. These authors have written the guide lines for quantitation of renal plasma flow by scintillation scanning. In our own experience we have been more successful in comparing the one kidney against the other than we have been in translation of the scan into absolute values, representing renal plasma or renal blood flow quantitated by chemical or maximal values determined by flowmeters at operation. Any kidney mobilized adequately for nephrolithotomy inevitably is repositioned in the postoperative state and it is not possible to be certain what influence this has on the counts from the scintillation camera, which is a 2dimensional study. Although the average plasma flow was increased postoperatively in the non-operated kidney there were 4 non-operated kidneys (31 per cent of patients) that showed a decrease in renal plasma flow of the same order of magnitude as occurred in 9 (69 per cent) of the operated kidneys. The clinical impact of this presentation lies in the question "If even 1 of 13 kidneys can be subjected to this type of operation without significant change in plasma flow, why could not this result be achieved in the other 12?" Stated another way, if two-thirds of the series have a decrease in plasma flow of <100 cc per minute what happened to the plasma flow in the remaining units, which were decreased by 100 to 250 cc per minute? Studies of the type reported here are essential to the continuing advancement of urologic thought and performance.
William H. Boyce Department of Surgery Section of Urology Bowman Gray School of Medicine Winston-Salem, North Carolina
THE e..TO-URNAL OF UROLOGY
CopyTight © 1981 by The VVilliaDJ.s & 1_1,/ilki:n.s Co.
Printed
U.S.A.
TI-IE RENAL TIVE SCINTILLATION CAMERA STUDY FOR DETERMINATION OF RENAL FUNCTION AFTER ANATROPHIC NEPHROLITHOTOMY RAJU THOMAS, RONALD W. LEWIS AND JAMES A. ROBERTS From the Department of Urology, Tulane University, New Orleans, Louisiana
ABSTRACT
The effect of hypothermic anatrophic nephrolithotomy was evaluated in 13 patients by comparing preoperative and postoperative renal quantitative scintillation camera studies. Total renal function as measured by effective renal plasma flow remained normal postoperatively. However, the operated kidney had a significant loss of function with a proportionate compensatory hypertrophy of the contralateral kidney. This finding explains the normal total renal function, the good end result of the operation being stable renal function if stones do not recur. Management of staghorn calculi of the kidney always has been a challenge to the urologic surgeon. There have been advocates of a conservative (that is medical treatment) as well as a more aggressive (operative) approach to staghorn calculi. In 1971 Libertino and associates reported their experience with 17 patients and concluded that medical treatment was the choice for asymptomatic staghom calculi. 1 More recently, others have shown the deleterious effect of the unoperated staghorn calculus and have advocated an operative approach. 2- 5 Of the operative techniques hypothermic anatrophic nephrolithotomy has been shown to be an effective method of surgically dealing with the staghom calculus. 4 - 6 Using serum creatinine and creatinine clearance values in 30 solitary kidneys, Stubbs and associates have shown that no statistically significant difference was found between the average preoperative and postoperative renal function values. 6 Boyce and Elkins evaluated renal function by blood urea nitrogen (BUN) only and reported that renal function had improved or remained stable postoperatively in aJl but 2 of 100 consecutive cases of an.atrophic nephrolithotomy. 4 Wickham and associates similarly have reported some improvement of serum creatinine and creatinine clearance levels in 100 cases of nephrolithotomy under hypothermia. 7 However, there have been no reports that provide any details as far as individual renal function is concerned. 1- 5 No study has been done on the effect of c.n-,h·on nephrolithotomy on the individual function of either the involved or the uninvolved kidney. We herein have used renal nt,,t,,trn .. scintillation gamma camera studies to evaluate and total renal function. These studies were obtained rn,,arn.-,cn·<> t iu,,lu and compared to those done oo,st,:,p,ers determine the effect of hypotherm1c n:.ofn\rm on individual as weJ.I as total renal ru11ctrn,1.
plasma flow with this technique has been shown to be an accurate indicator of renal function. 8 The standard hypothermic anatrophic nephrolithotomy as described initially by Smith and Boyce in 1968 was done. 5 Most of these procedurns were done by a resident under the direct supervision of faculty members. The average ischemia time was 74 minutes. The average blood loss was 1.3 units (675 cc) and an average of l.l units (542 cc) of blood was replaced. Postoperative BUN, creatinine and renal quantitative scintillation camera studies were done with an average interval between the operative procedure and the postoperative renal scan of 13.6 months. BUN and creatinine values were not available for 1 of the 13 patients. Statistical analysis was done using Student's paired t test. RESULTS
Preoperative and postoperative BUN and creatinine values are presented in table l. No statistical difference was found during this time. The preoperative and postoperative effective renal plasma flow (total as well as individual kidney) values ru:e presented in table 2. The total renal function as measured by the total effective renal plasma flow was slightly decreased (from 591 to 545 ml. per minute per 1.73 M. 2 ), which was of no statistical significance. However, the effective renal plasma flow to the operated side showed a significant postoperative decrease (from 258 to 182 ml. per minute per 1.73 M.2, p <0.01). At the same tin1e the non-operated kidney showed a mean increase in effective renal plasma flow (from 321 to 362 mL per minute per L73 M. 2 ). DISCUSSION
~~.VH~V•~UC.J
METHODS
Of 35 patients treated with various modalities for staghorn calculi 13 who underwent hypothermic anatrophic nephrolithotomy for a unilateral staghom calculus were selected for study. No disease or abnormality was found in the contralateral kidney and, thus, it acted as a control. Each of these 35 patients had preoperative evaluation with BUN, creatinine and the renal quantitative scintillation camera study using 131iodine hippuran. Determination of effective renal Accepted for publication June 27, 1980. Read at annual meeting of Southeastern Section, American Urological Association, San Juan, Puerto Rico, March 23-27, 1980. Supported by United States Public Health Service Grant 5 T32 AM07212. 287
If we had used the usual parameters of evaluating the postoperative renal function (BUN and creatinine), as was done in the past, we would have concluded that renal function had remained stable or unchanged. In addition, the renal quantitative scintillation camera study showed that total renal function remained unchanged. However, on comparing individual renal function we have found that the operated kidney does have a significant loss of function, while the contralateral kidney has a proportionate compensatory hypertrophy. The emerging consensus is that hypothermic anatrophic nephrolithotomy is an effective method to manage surgically staghorn calculus disease. The effect of this procedure on renal function has remained controversial. Various reports have found stable or improved renal function postoperatively. 3 • 4 • 6• 7 Gil-Vernet has maintained that this procedure compromises renal function. 9 We believe that BUN, creatinine and creatinine
288
THOMAS, LEWIS AND ROBERTS
clearance are not adequate to evaluate accurately the effect of this procedure. The renal quantitative scintillation camera study is an excellent method to determine individual and total renal function as 1. Comparison of preoperative and postoperative studies in patients with unilateral staghorn calculus and anatrophic nephrolithotomy
TABLE
BUN (mg./ml.)
Pt. No. 1 2 3 4 5 6 7 8 9 10 11 12
Creatinine (mg./ml.)
Preop.
Postop.
Preop.
Postop.
12 9 16 15
18 10 10 17 30 10
LO 0.7 L2 1.1 L4 LO L2 1.1 LO L2 0.8 L5
1.1 0.8
16
15 11 12 16 13 19 24
10 11 19 14 23
L2 L6 0.9 LO 0.5 L2 L4 0.8 L3
No statistical differences by Student's paired t test. TABLE
2. Preoperative and postoperative effective renal plasma flow (ml. per minute per 1. 73 M. 2)
Pt. No.
Side
Preop.
Postop.
Total effective renal plasma fiow * 1 662 721 2 670 558 537 3 521 398 4 467 488 5 375 524 401 6 696 7 575 629 586 8 9 689 698 659 659 10 523 502 11 12 623 583 590 435 13 Mean 591 545 Individual effective renal plasma fiow-operated sidet 1 Rt. 333 299 Rt. 2 278 187 3 Rt. 276 201 4 Lt. 211 185 5 Lt. 101 73 6 Lt. 231 146 Lt. 397 164 7 8 Lt. 254 87 Lt. 9 323 290 10 Lt. 269 139 11 Rt. 248 196 Lt. 12 210 239 Lt. 227 161 13 Mean 258 182 Individual effective renal plasma fiow-non-operated side* 1 Lt. 328 421 Lt. 2 371 392 Lt. 261 3 319 281 4 Rt. 186 5 Rt. 302 387 254 Rt. 6 292 411 Rt. 7 298 499 Rt. 8 374 408 9 Rt. 365 Rt. 519 10 389 Lt. 275 11 305 Rt. 12 260 344 274 Rt. 362 13 362 Mean 321
*No statistical differences by Student's paired t test.
t Significant statistical differences by Student's paired t test (p <0.01).
determined by the individual and total effective renal plasma flow. This valuable diagnostic tool has helped us in determining that the kidney undergoing hypothermic anatrophic nephrolithotomy does have a significant decrease in function, which almost always is compensated adequately by hypertrophy of the contralateral kidney, thereby maintaining stable total renal function. Therefore, we agree that total renal function remains normal. Thus, despite some loss of renal function from the operation, as we have shown, progressive loss is prevented by anatrophic nephrolithotomy as opposed to no operative treatment. This finding was consistent in our patients with a unilateral staghorn calculus who underwent anatrophic nephrolithotomy. We favor an aggressive operative approach for staghorn calculus disease and believe that hypothermic anatrophic nephrolithotomy is a good operative approach to the management of this disease entity. REFERENCES
1. Libertino, J. A., Newman, H. R., Lytton, B. and Weiss, R. M.: Staghom calculi in solitary kidneys. J. Urol., 105: 753, 1971. 2. Singh, M., Chapman, R., Tresidder, G. C. and Blandy, J.: The fate of the unoperated staghom calculus. Brit. J. Urol., 45: 581, 1973. 3. Blandy, J. P. and Singh, M.: The case for a more aggressive approach to staghorn stones. J. Urol., 115: 505, 1976. 4. Boyce, W. H. and Elkins, I. B.: Reconstructive renal surgery following anatrophic nephrolithotomy: followup of 100 consecutive cases. J. Urol., 111: 307, 1974. 5. Smith, M. J. V. and Boyce, W. H.: Anatrophic nephrotomy and plastic calyrhaphy. J. Urol., 99: 521, 1968. 6. Stubbs, A. J., Resnick, M. I. and Boyce, W. H.: Anatrophic nephrolithotomy in the solitary kidney. J. Urol., 119: 457, 1978. 7. Wickham, J.E. A., Coe, N. and Ward, J.P.: One hundred cases of nephrolithotomy under hypothermia. J. Urol., 112: 702, 1974. 8. Schlegel, J. U. and Hamway, S. A.: Individual renal plasma flow determination in 2 minutes. J. Urol., 116: 282, 1976. 9. Gil-Vernet, J.: New surgical concepts in removing renal calculi. Urol. Int., 20: 255, 1965.
EDITORIAL COMMENT There are so many variables in individual patients and in surgical procedures. These authors have written the guide lines for quantitation of renal plasma flow by scintillation scanning. In our own experience we have been more successful in comparing the one kidney against the other than we have been in translation of the scan into absolute values, representing renal plasma or renal blood flow quantitated by chemical or maximal values determined by flowmeters at operation. Any kidney mobilized adequately for nephrolithotomy inevitably is repositioned in the postoperative state and it is not possible to be certain what influence this has on the counts from the scintillation camera, which is a 2dimensional study. Although the average plasma flow was increased postoperatively in the non-operated kidney there were 4 non-operated kidneys (31 per cent of patients) that showed a decrease in renal plasma flow of the same order of magnitude as occurred in 9 (69 per cent) of the operated kidneys. The clinical impact of this presentation lies in the question "If even 1 of 13 kidneys can be subjected to this type of operation without significant change in plasma flow, why could not this result be achieved in the other 12?" Stated another way, if two-thirds of the series have a decrease in plasma flow of <100 cc per minute what happened to the plasma flow in the remaining units, which were decreased by 100 to 250 cc per minute? Studies of the type reported here are essential to the continuing advancement of urologic thought and performance.
William H. Boyce Department of Surgery Section of Urology Bowman Gray School of Medicine Winston-Salem, North Carolina