© 1990 S. Karger AG, Basel 0302-2838/90/0183-0207$2.7 5/0
EurUrol 1990;18:207-210
Diagnosis and Treatment of Retrocaval Ureter 1608193
Zhang Xiaodong, Hou Shukun, Zhu Jichuan, Wang Xiaofeng, Meng Guangdong, Qu Xingke Department of Urology, People’s Hospital, Beijing Medical University, Beijing, People’s Republic of China
Key Words. Retrocaval ureter • Hydronephrosis • Vena cava supporter Abstract. 34 cases of retrocaval ureter of our country, including 2 of our hospital, were studied. The embryologie pathology, diagnosis and treatment of the disorder are discussed. The choice of operative methods and ‘vena cava supporter’ are also described.
Patients and Methods Among the 34 patients, there were 27 male and 7 female sub jects: their age ranged from 20 to 67 years. The male/female ratio was 4.0:1. The main clinical features included right flank pain in 34, bladder irritation in 9 and hematuria in 24 cases. Urography showed right hydronephrosis in 29 patients, while being normal in 3 cases. The other 2 cases showed unsatisfactory patterns. There were 32 cases of type 1, and 2 cases of type 2 retro caval ureter. Eight patients of type 1 retrocaval ureter had stones of the collective system additionally.
Treatment Uretero-ureteric anastomosis was performed in 24, nephrec tomy in 6 cases, and 3 patients were treated conservatively. Ure tero-ureteric reanastomosis was done in 1 patient after primary anastomosis because of anastomotic stricture. Postoperative symp toms and hydronephrosis were more or less alleviated in these cases.
Discussion Embryology and Pathology In the embryo, the ureter ascends with the kidneys at 12 weeks gestational age. First it passes in front of the posterior cardinal vena, and then turns behind the vena. If the posterior cardinal vena does not form a segment of the inferior vena cava, then a retrocaval ureter is the consequence. The venous ring is made up of the poste rior cardinal vena and of the developing superior cardi nal vena. If the ureter passes through the venous ring, it is called circumcaval ureter. The morbidity for retro caval ureter is nearly 1:1,500. The main causes of hydronephrosis are lumen steno sis, torsion, and adhesion of the retrocaval segment. This segment is compressed by the greater psoas muscle, spi nal column, and vena cava, which leads to inflammation and fibrosis of the segment, and to lowered compliance of the ureteral smooth muscle, resulting in urinary stasis. All above mentioned features are identified pathologically [8]; circular muscle proliferation, enlargement, and in flammatory cell infiltration are present microscopically. Clinical Features The patients usually are in their third or fourth decade. Right flank discomfort or pain is the predomiDownloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
Retrocaval ureter, also called anteureteral vena is a rare disease which is due to a maldevelopment of the inferior vena cava. Since its first description by Hochstetter in 1893 [cited in ref. 1], close to 200 cases have been presented all over the world. Herein, we report 2 cases from our medical unit, and 32 cases from other hospitals in China, with a review of the literature [2-7].
nant symptom. The pain is intermittent, a dull aching, or sometimes colicky in nature. Other symptoms and signs mostly related to the severity of hydronephrosis from ureteral stenosis and the presence of urinary infection and stone formation include hematuria, pyuria, fever, and swelling of the kidney. The resulting hydronephrosis may be entirely silent, without any symptom. Diagnosis The diagnosis is mainly based on roentgenography. Kidney, ureter and bladder are normal except in the case with concomitant stone formation. The intravenous uro gram (IVU) in the early stage of ureteral stenosis only shows a dilatation of the renal pelvis, calyces and upper ureter above the site of obstruction. Renal function remains unimpaired. Retrograde pyelography is of great help in the diagnosis. It can show the characteristic S shape and midline deviation of the ureter in anteropos terior view, as well as the compression of the ureter to the anterior margin of L3-L4 in lateral view, while in normal condition, there is a certain distance between the ureter and the anterior margin. Bateson and Atkinson [9] distinguished two types of retrocaval ureter in accordance with the common radio logical appearance: type 1 (low loop): In the IVU, the dilated upper ureter is seen to descend from the renal pelvis and then to curve upwards and medially, forming a reversed J. The retrograde pyelogram shows an Sshaped outline of the ureter. The retrocaval segment is seen more frequently at the level of the third lumbar vertebra. Type 2 (high loop): The renal pelvis and upper ureter lie horizontally, the retrocaval element of the ure ter is at the same level of the renal pelvis. The retrograde pyelogram shows an inverted J shape of the involved ureter, generally with a normal urogram or mild hydro nephrosis. This type is rare, around 10% in our coun try. In our group studied, 28 of the 34 patients could be diagnosed preoperatively with urography. This was not the case for the other 6 because of poor urograms and inexperience. Retrocaval ureter should be differentiated from retro peritoneal mass and retroperitoneal fibrosis. In retro peritoneal mass, the urogram reveals lateral deviation of the ureter from compression of the mass. In retroperito neal fibrosis, the ureter is involved on both sides and the whole segment of the ureter is stiff in the urogram. A medial deviation of the ureter can be seen in normal condition and can be differentiated from retrocaval ure ter by lateral pyelogram.
Xiaodong/Shukun/Jichuan/Xiaofeng/Guangdong/Xingke
Ultrasound scan and CT are also helpful in the diag nosis. Gelfter [10] was the first to successfully identify this anomaly with CT. Retrograde pyelogram in combi nation with venography of the inferior vena cava is used as well. Treatment The treatment consists of operative and nonoperative methods. The choice of the method depends primarily on the severity of the hydronephrosis, impairment of renal function, and the type of anomaly. Nonoperative Method Conservative treatment and periodical examination should be given o those patients without hydronephrosis, infection, and stone formation, or even to those with mild hydronephrosis. Surgical Treatment Uretero-Ureteric Anastomosis. This procedure has ex tensive indications. The majority of the authors advo cate Harrill’s method by which a section is made at the level of the pelvis just above the ureteropelvic junction. The advantage of this approach is that the vascular sup plies of the pelvis and proximal ureter are abundant, as compared to those at the middle third of the ureter, and postoperative stricture at the anastomotic site is less like ly. If an 8F catheter cannot pass through the segment easily, this stenotic section of the ureter must be excised, and a dismembered pyeloplasty should be done. In 2 patients of our hospital, the whole segment below the obstructed ureter was stenotic, the wall of the ureter was thinner, badly developed, and lacked elasticity. Three weeks after the anastomosis, the pyelogram demon strated delayed excretion of the contrast medium, and the funnel-shaped outflow portion was not clear (fig. 1). Preoperative visualization of the ureteral segment be low the obstruction is very important, as the choice of the procedure depends on its results. If the stenotic seg ment is short (< 5.0 cm), relocation and end-to-end anastomosis is indicated. Otherwise, intestinal replace ment or nephrectomy should be considered. Additionally, we would like to introduce our steps to observe the stenotic ureter by retrograde pyelography. (1) Catheterization to the pelvis cystoscopically and ob servation of pyelogram and screen. (2) Moving the cath eter 5.0 cm below the obstructed site and injection of additional medium, and again observation. If the ob served segment is too stenotic, now a linear appearance Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
208
209
Diagnosis and Treatment of Retrocaval Ureter
------ Retracaval ureter
— Vena cava
occurs, or even nothing appears at all. (3) Retraction of the catheter just above the ureteral orifice, and again watching. Figure 2 shows a 10- to 12-cm stenotic seg ment below the postcaval ureter. The longer stenotic seg ment was detected intraoperatively. Reanastomosis of the Vena cava. Goodwin et al. [11] and Carrion et al. [12] divided and reanastomosed the vena cava successfully after relocating the ureter anteri orly. This procedure has its own shortcomings and oper ative risks, and severe complications. Nephrectomy. In case of severe hydronephrosis and infection, with diminished renal function, nephrectomy is indicated.
Vena cava supporter
3
Vena cava Supporter. We suggest to use a ‘vena cava supporter’ (fig. 3) for those cases with lumen stenosis caused only by torsion and compression by the vena. Adhesive tissue around the ureter, vena, and spinal col umn is well dissected, and the torsion of the ureter is corrected. A piece of a chemical or metal substance, as well as surrounding soft tissue, such as the greater psoas muscle, can be placed between the vena and the ureter. Generally, the prognosis is good after this operation, but the recovering is very slow due to compliance of the pelvis from long-term higher intrapelvic pressure. The isotopic urogram and diuretic IVU are valuable in pre dicting the success of the operation. Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
Fig. 1. Postoperative pyelogram. Fig. 2. Longer stenotic segment in preoperative pyelogram. Fig. 3. Vena cava supporter.
References 1 Kerawi MM, et al: Circumcaval ureter: A report of four cases in children, with a review of the literature and a new classification. Br J Urol 1976,48:183. 2 J Chin Surg 1955;4:27, 1956;4:308, 1959;4:434, 1959;7:1143, 1986;1:38. 3 J Chin Urol 1980;3:C4, 1983;4:152, 1983;4:210, 1984;6:337. 4 J Chin Radiol 1959;2:104, 1978,2:100. 5 J Clin Urol 1986;2:100, 1988;1:36, 1989;2:104. 6 Zhejiang Med 1959;2:104. 7 Guangxi Med 1981 ;2:5 5. 8 Yan Chenglong, et al: Retrocaval ureter. J Chin Surg 1986; 1 : 38. 9 Bateson EM, Atkinson D: Circumcaval ureter: A new classifica tion. Clin Radiol 1969;20:173.
Xiaodong/Shukun/Jichuan/Xiaofeng/Guangdong/Xingke
10 Gelfter WB, et al: CT of circumcaval ureter. Am J Roentgenol Radium Ther Nucl Med 1978; 131:1086. 11 Goodwin WE, et al: Retrocaval ureter. Surg Gynecol Obstet 1957; 104:337. 12 Carrion H, et al: Retrocaval ureter: Report of 8 cases and the surgical managment. J Urol 1979; 121:514.
Zhang Xiaodong, MD Department of Urology People’s Hospital Beijing Medical University Beijing (China)
Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
210
EurUrol 1990;18:207-210
Diagnosis and Treatment of Retrocaval Ureter 1608193
Zhang Xiaodong, Hou Shukun, Zhu Jichuan, Wang Xiaofeng, Meng Guangdong, Qu Xingke Department of Urology, People’s Hospital, Beijing Medical University, Beijing, People’s Republic of China
Key Words. Retrocaval ureter • Hydronephrosis • Vena cava supporter Abstract. 34 cases of retrocaval ureter of our country, including 2 of our hospital, were studied. The embryologie pathology, diagnosis and treatment of the disorder are discussed. The choice of operative methods and ‘vena cava supporter’ are also described.
Patients and Methods Among the 34 patients, there were 27 male and 7 female sub jects: their age ranged from 20 to 67 years. The male/female ratio was 4.0:1. The main clinical features included right flank pain in 34, bladder irritation in 9 and hematuria in 24 cases. Urography showed right hydronephrosis in 29 patients, while being normal in 3 cases. The other 2 cases showed unsatisfactory patterns. There were 32 cases of type 1, and 2 cases of type 2 retro caval ureter. Eight patients of type 1 retrocaval ureter had stones of the collective system additionally.
Treatment Uretero-ureteric anastomosis was performed in 24, nephrec tomy in 6 cases, and 3 patients were treated conservatively. Ure tero-ureteric reanastomosis was done in 1 patient after primary anastomosis because of anastomotic stricture. Postoperative symp toms and hydronephrosis were more or less alleviated in these cases.
Discussion Embryology and Pathology In the embryo, the ureter ascends with the kidneys at 12 weeks gestational age. First it passes in front of the posterior cardinal vena, and then turns behind the vena. If the posterior cardinal vena does not form a segment of the inferior vena cava, then a retrocaval ureter is the consequence. The venous ring is made up of the poste rior cardinal vena and of the developing superior cardi nal vena. If the ureter passes through the venous ring, it is called circumcaval ureter. The morbidity for retro caval ureter is nearly 1:1,500. The main causes of hydronephrosis are lumen steno sis, torsion, and adhesion of the retrocaval segment. This segment is compressed by the greater psoas muscle, spi nal column, and vena cava, which leads to inflammation and fibrosis of the segment, and to lowered compliance of the ureteral smooth muscle, resulting in urinary stasis. All above mentioned features are identified pathologically [8]; circular muscle proliferation, enlargement, and in flammatory cell infiltration are present microscopically. Clinical Features The patients usually are in their third or fourth decade. Right flank discomfort or pain is the predomiDownloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
Retrocaval ureter, also called anteureteral vena is a rare disease which is due to a maldevelopment of the inferior vena cava. Since its first description by Hochstetter in 1893 [cited in ref. 1], close to 200 cases have been presented all over the world. Herein, we report 2 cases from our medical unit, and 32 cases from other hospitals in China, with a review of the literature [2-7].
nant symptom. The pain is intermittent, a dull aching, or sometimes colicky in nature. Other symptoms and signs mostly related to the severity of hydronephrosis from ureteral stenosis and the presence of urinary infection and stone formation include hematuria, pyuria, fever, and swelling of the kidney. The resulting hydronephrosis may be entirely silent, without any symptom. Diagnosis The diagnosis is mainly based on roentgenography. Kidney, ureter and bladder are normal except in the case with concomitant stone formation. The intravenous uro gram (IVU) in the early stage of ureteral stenosis only shows a dilatation of the renal pelvis, calyces and upper ureter above the site of obstruction. Renal function remains unimpaired. Retrograde pyelography is of great help in the diagnosis. It can show the characteristic S shape and midline deviation of the ureter in anteropos terior view, as well as the compression of the ureter to the anterior margin of L3-L4 in lateral view, while in normal condition, there is a certain distance between the ureter and the anterior margin. Bateson and Atkinson [9] distinguished two types of retrocaval ureter in accordance with the common radio logical appearance: type 1 (low loop): In the IVU, the dilated upper ureter is seen to descend from the renal pelvis and then to curve upwards and medially, forming a reversed J. The retrograde pyelogram shows an Sshaped outline of the ureter. The retrocaval segment is seen more frequently at the level of the third lumbar vertebra. Type 2 (high loop): The renal pelvis and upper ureter lie horizontally, the retrocaval element of the ure ter is at the same level of the renal pelvis. The retrograde pyelogram shows an inverted J shape of the involved ureter, generally with a normal urogram or mild hydro nephrosis. This type is rare, around 10% in our coun try. In our group studied, 28 of the 34 patients could be diagnosed preoperatively with urography. This was not the case for the other 6 because of poor urograms and inexperience. Retrocaval ureter should be differentiated from retro peritoneal mass and retroperitoneal fibrosis. In retro peritoneal mass, the urogram reveals lateral deviation of the ureter from compression of the mass. In retroperito neal fibrosis, the ureter is involved on both sides and the whole segment of the ureter is stiff in the urogram. A medial deviation of the ureter can be seen in normal condition and can be differentiated from retrocaval ure ter by lateral pyelogram.
Xiaodong/Shukun/Jichuan/Xiaofeng/Guangdong/Xingke
Ultrasound scan and CT are also helpful in the diag nosis. Gelfter [10] was the first to successfully identify this anomaly with CT. Retrograde pyelogram in combi nation with venography of the inferior vena cava is used as well. Treatment The treatment consists of operative and nonoperative methods. The choice of the method depends primarily on the severity of the hydronephrosis, impairment of renal function, and the type of anomaly. Nonoperative Method Conservative treatment and periodical examination should be given o those patients without hydronephrosis, infection, and stone formation, or even to those with mild hydronephrosis. Surgical Treatment Uretero-Ureteric Anastomosis. This procedure has ex tensive indications. The majority of the authors advo cate Harrill’s method by which a section is made at the level of the pelvis just above the ureteropelvic junction. The advantage of this approach is that the vascular sup plies of the pelvis and proximal ureter are abundant, as compared to those at the middle third of the ureter, and postoperative stricture at the anastomotic site is less like ly. If an 8F catheter cannot pass through the segment easily, this stenotic section of the ureter must be excised, and a dismembered pyeloplasty should be done. In 2 patients of our hospital, the whole segment below the obstructed ureter was stenotic, the wall of the ureter was thinner, badly developed, and lacked elasticity. Three weeks after the anastomosis, the pyelogram demon strated delayed excretion of the contrast medium, and the funnel-shaped outflow portion was not clear (fig. 1). Preoperative visualization of the ureteral segment be low the obstruction is very important, as the choice of the procedure depends on its results. If the stenotic seg ment is short (< 5.0 cm), relocation and end-to-end anastomosis is indicated. Otherwise, intestinal replace ment or nephrectomy should be considered. Additionally, we would like to introduce our steps to observe the stenotic ureter by retrograde pyelography. (1) Catheterization to the pelvis cystoscopically and ob servation of pyelogram and screen. (2) Moving the cath eter 5.0 cm below the obstructed site and injection of additional medium, and again observation. If the ob served segment is too stenotic, now a linear appearance Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
208
209
Diagnosis and Treatment of Retrocaval Ureter
------ Retracaval ureter
— Vena cava
occurs, or even nothing appears at all. (3) Retraction of the catheter just above the ureteral orifice, and again watching. Figure 2 shows a 10- to 12-cm stenotic seg ment below the postcaval ureter. The longer stenotic seg ment was detected intraoperatively. Reanastomosis of the Vena cava. Goodwin et al. [11] and Carrion et al. [12] divided and reanastomosed the vena cava successfully after relocating the ureter anteri orly. This procedure has its own shortcomings and oper ative risks, and severe complications. Nephrectomy. In case of severe hydronephrosis and infection, with diminished renal function, nephrectomy is indicated.
Vena cava supporter
3
Vena cava Supporter. We suggest to use a ‘vena cava supporter’ (fig. 3) for those cases with lumen stenosis caused only by torsion and compression by the vena. Adhesive tissue around the ureter, vena, and spinal col umn is well dissected, and the torsion of the ureter is corrected. A piece of a chemical or metal substance, as well as surrounding soft tissue, such as the greater psoas muscle, can be placed between the vena and the ureter. Generally, the prognosis is good after this operation, but the recovering is very slow due to compliance of the pelvis from long-term higher intrapelvic pressure. The isotopic urogram and diuretic IVU are valuable in pre dicting the success of the operation. Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
Fig. 1. Postoperative pyelogram. Fig. 2. Longer stenotic segment in preoperative pyelogram. Fig. 3. Vena cava supporter.
References 1 Kerawi MM, et al: Circumcaval ureter: A report of four cases in children, with a review of the literature and a new classification. Br J Urol 1976,48:183. 2 J Chin Surg 1955;4:27, 1956;4:308, 1959;4:434, 1959;7:1143, 1986;1:38. 3 J Chin Urol 1980;3:C4, 1983;4:152, 1983;4:210, 1984;6:337. 4 J Chin Radiol 1959;2:104, 1978,2:100. 5 J Clin Urol 1986;2:100, 1988;1:36, 1989;2:104. 6 Zhejiang Med 1959;2:104. 7 Guangxi Med 1981 ;2:5 5. 8 Yan Chenglong, et al: Retrocaval ureter. J Chin Surg 1986; 1 : 38. 9 Bateson EM, Atkinson D: Circumcaval ureter: A new classifica tion. Clin Radiol 1969;20:173.
Xiaodong/Shukun/Jichuan/Xiaofeng/Guangdong/Xingke
10 Gelfter WB, et al: CT of circumcaval ureter. Am J Roentgenol Radium Ther Nucl Med 1978; 131:1086. 11 Goodwin WE, et al: Retrocaval ureter. Surg Gynecol Obstet 1957; 104:337. 12 Carrion H, et al: Retrocaval ureter: Report of 8 cases and the surgical managment. J Urol 1979; 121:514.
Zhang Xiaodong, MD Department of Urology People’s Hospital Beijing Medical University Beijing (China)
Downloaded by: University of Exeter 144.173.6.94 - 5/7/2020 2:21:18 AM
210
