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Endovascular treatment of splenic artery aneurysm with splenic preservation
European Journal of Radiology Extra 61 (2007) 65–68
Endovascular treatment of splenic artery aneurysm with splenic preservation Naga Venkatesh Gupta Jayanthi ∗ , Ahmed Mohamed Mudawi, Raman Uberoi Department of Interventional Radiology and Vascular Surgery, Queen Elizabeth Hospital, Gateshead, United Kingdom Received 7 June 2006; received in revised form 11 September 2006; accepted 11 October 2006
Abstract Splenic artery aneurysm (SAA) is the commonest visceral artery aneurysm. Surgical or endovascular treatment of SAA may result in loss of most or all of spleen. We present a case of an aneurysm of superior segmental branch of splenic artery, which was successfully treated by sub-selective embolisation of the feeding arterial branch. The splenic function was preserved and hence precluding pneumococcal vaccines and long-term antibiotics. © 2006 Published by Elsevier Ireland Ltd. Keywords: Splenic artery; Aneurysm; Embolisation
1. Introduction SAAs are the third commonest aneurysms, after abdominal aortic and iliac aneurysms and are the most common visceral artery aneurysm [1]. SAAs occur predominantly in females [2] and in hepatic transplant patients [3]. In female patients SAAs are often diagnosed for the first time in pregnancy [4]. A strong association has been found between pregnancy and SAA. This is thought to be due to hormonal changes in pregnancy causing weakness of the vessel wall [2]. Unlike with other aneurysms, atherosclerosis is not the commonest aetiological factor of SAAs [5,6]. Although, in most of the cases there is no detectable cause, there is an increased risk of SAA in patients with portal hypertension, congenital or inherited vascular or connective tissue disorders [2,7]. In the majority of cases, diagnosis of SAA is incidental [4,8]. Symptomatic SAAs present with either abdominal pain or rupture [2]. Rupture of SAA can present either in one or two stages. The two-stage rupture, also called ‘double rupture’ was first described by Brockman [2,9]. The first stage involves a contained rupture of the aneurysm into the lesser ∗ Corresponding author at: 4 Charlton Court, Hoole Road, Chester CH2 3PB, United Kingdom. Tel.: +44 7790632511; fax: +44 1978 727000. E-mail address: [email protected] (N.V.G. Jayanthi).
1571-4675/$ – see front matter © 2006 Published by Elsevier Ireland Ltd. doi:10.1016/j.ejrex.2006.10.006
sac which acts like a tamponade for further bleeding. At this stage the patient can complain of varying degree of abdominal pain with no signs of haemorrhagic shock. This initial stage is followed by rupture into the main peritoneal cavity and presents with sudden onset of frank haemorrhagic shock. A 3–9.6% of SAAs rupture with an increased incidence during pregnancy [2]. Rupture of SAA is associated with a mortality rate of 36% [8]. Importantly, SAA rupture in pregnancy carries a maternal mortality of 70% and a 90% foetal mortality [10]. Significant risk factors for rupture of SAA include portal hypertension with splenomegaly [11] and cirrhosis due to α − 1 antitrypsin deficiency [7].
2. Case report A 42-year-old man presented to our emergency department with epigastric pain, tenderness and nausea and vomiting. His past medical history was unremarkable with no history of alcohol abuse. Serum electrolytes, amylase and liver function tests were normal. Gall stones were absent on ultrasound scan of abdomen, however, a circular mass, 5 cm in diameter in the region of the tail of pancreas was seen. Contrast enhanced CT of the abdomen demonstrated a splenic artery aneurysm (SAA). Angiographic examination
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Fig. 1. Selective examination of the distal splenic artery (A) demonstrated an aneurysm arising from the superior segmental branch (arrow) with no communications from the inferior segmental branch. During the procedure SAA started to leak (B) and the patient experienced a lot of pain. Superior segmental branch was sub-selectively cathetrised and embolised (C).
of the celiac axis was then undertaken with an intention to treat the aneurysm endovascularly. Selective angiographic examination of the splenic artery using a 5F SOS Omni catheter (Angiodynamics, Massachusetts, USA) confirmed an aneurysm arising from the superior segmental branch of the splenic artery (Fig. 1A) with no communications with the inferior segmental branch. On sub-selective catheterisation of the superior segmental branch using a 5F Cobra catheter (Cordis, UK) and curved terumo (Terumo Corporation, Japan), the aneurysm started leaking and the patient experienced a lot of pain (Fig. 1B). The aneurysm was immediately embolised with 35.3.3 and 35.5.3 coils (Cook, UK) (Fig. 1C). A CT scan of the abdomen on the following day demonstrated contrast filled aneurysm with an air bubble, which was presumably introduced during embolisation. There was an area of low attenuation in the spleen, consistent
with an infarct of about 30–40% of the spleen (Fig. 2A). The patient was asymptomatic, apyrexial and haemodynamically stable after the procedure and was discharged after 48 h of observation. Follow up abdominal CT scan at 3 months confirmed an occluded aneurysm (Fig. 2B) with infraction of approximately 50% of the spleen.
3. Discussion All symptomatic SAAs need to be treated. However, there is no consensus of the timing of treatment of asymptomatic SAAs. Nevertheless, it is generally advised that any aneurysms >2 cm in diameter should be treated [12,13]. In addition, due to an increased risk of rupture in pregnancy with associated high foetal and maternal mortality and relatively
N.V.G. Jayanthi et al. / European Journal of Radiology Extra 61 (2007) 65–68
Fig. 2. CT abdomen 1-day post-embolisation demonstrated air bubble in the aneurysm, which probably was introduced during the procedure. There was an area of low attenuation of about 30–40% which was exaggerated in post-contrast images (A). Contrast CT scan after 3 months demonstrates exclusion of the aneurysm with about 50% of the spleen well perfused (B).
low post-operative morbidity, SAAs in young (childbearing age) and pregnant women should be promptly treated [2,4]. SAAs in all the patients undergoing liver transplants should also be treated [13] due to an increased incidence of rupture. SAAs can be treated either surgically (open or laparoscopic) [14] or endovascularly. One of the important features of SAAs that influence the mode of treatment is its anatomy [2,4,15]. Proximal aneurysms can be treated by ligation or aneurysmectomy. However, most of the SAAs occur in the distal third of the splenic artery and such aneurysms are best treated by resection of both the aneurysm and spleen [8,12]. Distal lesions can also be treated by means of endovascular embolisation. In most of the cases, treatment of a SAA is associated with a significant loss of the splenic function. Even though, splenectomy is performed regularly for various reasons, it is important to preserve splenic function. Patients after splenectomy are prone to bacterial infections. Post-splenectomy sepsis is a serious overwhelming infection following splenectomy. Impaired bacterial clearance, mainly of encapsulated
67
Gram-positive bacteria such as Streptococcus pneumoniae is believed to cause such an infection and occurs in about 0.6% of children and 0.3% of adults [16]. In order to prevent such an infection, patients are started on long-term antibiotics and vaccines. In view of the importance of the splenic function and post-splenectomy syndrome, distal SAAs have been treated surgically with excision and end to end anatomosis of the splenic artery [17] and stent grafting [1,18], thus preserving splenic function. Treatment of a distal SAA by means of endovascular embolisation can be an ideal option, especially when the aneurysm is arising from a splenic artery branch. In the case presented in this report, the aneurysm was originating from the superior segmental branch of the splenic artery. Examination of the proximal celiac axis was normal. There was no communication between the aneurysm and the inferior segmental branch of splenic artery. The superior segmental branch of the splenic artery was sub-selectively catheterised and then embolised resulting in successful exclusion of the aneurysm, which may otherwise have required a more invasive procedure and may have required splenectomy [15] due to the distal nature of the aneurysm. The patient in this case report did not demonstrate any clinical signs of infection during follow up. Partial or sub-total splenectomy has been performed successfully for various haematological conditions [19–21]. In these series up to 80–90% was resected. It has been demonstrated that the splenic function was preserved despite partial or sub-total splenectomy. Follow up CT scan at 3 months demonstrated that up to a 50% of the spleen was well perfused.
4. Conclusion Although doubts have been raised regarding endovascular treatment for visceral artery aneurysms [15], this case report clearly demonstrates that a distal splenic artery aneurysm arising from a splenic artery branch can be successfully treated with sub-selective endovascular embolisation. Importantly, most of the spleen can be preserved, thus precluding long-term morbidity that is associated with the loss of splenic function and avoiding the need for long-term vaccines and antibiotics.
References [1] Arepally A, Dagli M, Hofmann LV, Kim HS, Cooper M, Klein A. Treatment of splenic artery aneurysm with use of a stent-graft. J Vasc Interv Radiol 2002;13(6):631–3. [2] Selo-Ojeme DO, Welch CC. Review: spontaneous rupture of splenic artery aneurysm in pregnancy. Eur J Obstet Gynecol Reprod Biol 2003;109(2):124–7. [3] DeRoover A, Sudan D. Treatment of multiple aneurysms of the splenic artery after liver transplantation by percutaneous embolization and laparoscopic splenectomy. Transplantation 2001;72(5):956–8.
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[4] Hallett Jr JW. Splenic artery aneurysms. Semin Vasc Surg 1995; 8(4):321–6. [5] Lee PC, Rhee RY, Gordon RY, Fung JJ, Webster MW. Management of splenic artery aneurysms: the significance of portal and essential hypertension. J Am Coll Surg 1999;189(5):483–90. [6] Stanley JC, Fry WJ. Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 1974;76(6):898–909. [7] Gaglio PJ, Regenstein F, Slakey D, et al. Alpha-1 antitrypsin deficiency and splenic artery aneurysm rupture: an association? Am J Gastroenterol 2000;95(6):1531–4. [8] Messina LM, Shanley CJ. Visceral artery aneurysms. Surg Clin North Am 1997;77(2):425–42. [9] Brockman RL. Aneurysm of splenic artery. Br J Surg 1929; 30(17):692–3. [10] Hillemanns P, Knitza R, Muller-Hocker J. Rupture of splenic artery aneurysm in a pregnant patient with portal hypertension. Am J Obstet Gynecol 1996;174(5):1665–6. [11] Pomerantz RA, Eckhauser FE, Strodel WE, Knol JA, Turcotte JG. Splenic aneurysm rupture in cirrhotic patients. Arch Surg 1986;121(9):1095–6. [12] de Perrot M, Buhler L, Deleaval J, Borisch B, Mentha G, Morel P. Management of true aneurysms of the splenic artery. Am J Surg 1998;175(6):466–8. [13] Mattar SG, Lumsden AB. The management of splenic artery aneurysms: experience with 23 cases. Am J Surg 1995;169(6):580–4.
[14] de Csepel J, Quinn T, Gagner M. Laparoscopic exclusion of a splenic artery aneurysm using a lateral approach permits preservation of the spleen. Surg Laparosc Endosc Percutan Technol 2001;11(3):221–4. [15] Saltzberg SS, Maldonado TS, Lamparello PJ, et al. Is endovascular therapy the preferred treatment for all visceral artery aneurysms? Ann Vasc Surg 2005;19(4):507–15. [16] Okinaga K, Giebink GS, Rich RH, Baesl TJ, Krishnanaik D, Leonard AS. The effect of partial splenectomy on experimental pneumococcal bacteremia in an animal model. J Pediatr Surg 1981;16(5):717–24. [17] Chakfe N, Mantz F, Kretz JG, Gasser B, Loson R, Eisenmann B. Treatment of a distal splenic artery aneurysm with splenic conservation. A case report. J Cardiovasc Surg (Torino) 1993;34(6):503–6. [18] Moyer HR, Hiramoto JS, Wilson MW, Reddy P, Messina LM, Schneider DB. Stent-graft repair of a splenic artery aneurysm. J Vasc Surg 2005;41(5):897. [19] Rice HE, Oldham KT, Hillery CA, Skinner MA, 0’Hara SM, Ware RE. Clinical and haemotological benefits of partial splenectomy for congenital hemolytic anaemias in children. Ann Surg 2003;237(2): 281–8. [20] Bader-Meunier B, Gauthier F, Archambaud F, et al. Long-term evaluation of the beneficial effect of subtotal splenectomy for management of hereditary spherocytosis. Blood 2001;97(2):399–403. [21] Stoehr GA, Stauffer UG, Eber SW. Near-total splenectomy: a new technique for the management of hereditary spherocytosis. Ann Surg 2005;241(1):40–7.
Endovascular treatment of splenic artery aneurysm with splenic preservation Naga Venkatesh Gupta Jayanthi ∗ , Ahmed Mohamed Mudawi, Raman Uberoi Department of Interventional Radiology and Vascular Surgery, Queen Elizabeth Hospital, Gateshead, United Kingdom Received 7 June 2006; received in revised form 11 September 2006; accepted 11 October 2006
Abstract Splenic artery aneurysm (SAA) is the commonest visceral artery aneurysm. Surgical or endovascular treatment of SAA may result in loss of most or all of spleen. We present a case of an aneurysm of superior segmental branch of splenic artery, which was successfully treated by sub-selective embolisation of the feeding arterial branch. The splenic function was preserved and hence precluding pneumococcal vaccines and long-term antibiotics. © 2006 Published by Elsevier Ireland Ltd. Keywords: Splenic artery; Aneurysm; Embolisation
1. Introduction SAAs are the third commonest aneurysms, after abdominal aortic and iliac aneurysms and are the most common visceral artery aneurysm [1]. SAAs occur predominantly in females [2] and in hepatic transplant patients [3]. In female patients SAAs are often diagnosed for the first time in pregnancy [4]. A strong association has been found between pregnancy and SAA. This is thought to be due to hormonal changes in pregnancy causing weakness of the vessel wall [2]. Unlike with other aneurysms, atherosclerosis is not the commonest aetiological factor of SAAs [5,6]. Although, in most of the cases there is no detectable cause, there is an increased risk of SAA in patients with portal hypertension, congenital or inherited vascular or connective tissue disorders [2,7]. In the majority of cases, diagnosis of SAA is incidental [4,8]. Symptomatic SAAs present with either abdominal pain or rupture [2]. Rupture of SAA can present either in one or two stages. The two-stage rupture, also called ‘double rupture’ was first described by Brockman [2,9]. The first stage involves a contained rupture of the aneurysm into the lesser ∗ Corresponding author at: 4 Charlton Court, Hoole Road, Chester CH2 3PB, United Kingdom. Tel.: +44 7790632511; fax: +44 1978 727000. E-mail address: [email protected] (N.V.G. Jayanthi).
1571-4675/$ – see front matter © 2006 Published by Elsevier Ireland Ltd. doi:10.1016/j.ejrex.2006.10.006
sac which acts like a tamponade for further bleeding. At this stage the patient can complain of varying degree of abdominal pain with no signs of haemorrhagic shock. This initial stage is followed by rupture into the main peritoneal cavity and presents with sudden onset of frank haemorrhagic shock. A 3–9.6% of SAAs rupture with an increased incidence during pregnancy [2]. Rupture of SAA is associated with a mortality rate of 36% [8]. Importantly, SAA rupture in pregnancy carries a maternal mortality of 70% and a 90% foetal mortality [10]. Significant risk factors for rupture of SAA include portal hypertension with splenomegaly [11] and cirrhosis due to α − 1 antitrypsin deficiency [7].
2. Case report A 42-year-old man presented to our emergency department with epigastric pain, tenderness and nausea and vomiting. His past medical history was unremarkable with no history of alcohol abuse. Serum electrolytes, amylase and liver function tests were normal. Gall stones were absent on ultrasound scan of abdomen, however, a circular mass, 5 cm in diameter in the region of the tail of pancreas was seen. Contrast enhanced CT of the abdomen demonstrated a splenic artery aneurysm (SAA). Angiographic examination
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N.V.G. Jayanthi et al. / European Journal of Radiology Extra 61 (2007) 65–68
Fig. 1. Selective examination of the distal splenic artery (A) demonstrated an aneurysm arising from the superior segmental branch (arrow) with no communications from the inferior segmental branch. During the procedure SAA started to leak (B) and the patient experienced a lot of pain. Superior segmental branch was sub-selectively cathetrised and embolised (C).
of the celiac axis was then undertaken with an intention to treat the aneurysm endovascularly. Selective angiographic examination of the splenic artery using a 5F SOS Omni catheter (Angiodynamics, Massachusetts, USA) confirmed an aneurysm arising from the superior segmental branch of the splenic artery (Fig. 1A) with no communications with the inferior segmental branch. On sub-selective catheterisation of the superior segmental branch using a 5F Cobra catheter (Cordis, UK) and curved terumo (Terumo Corporation, Japan), the aneurysm started leaking and the patient experienced a lot of pain (Fig. 1B). The aneurysm was immediately embolised with 35.3.3 and 35.5.3 coils (Cook, UK) (Fig. 1C). A CT scan of the abdomen on the following day demonstrated contrast filled aneurysm with an air bubble, which was presumably introduced during embolisation. There was an area of low attenuation in the spleen, consistent
with an infarct of about 30–40% of the spleen (Fig. 2A). The patient was asymptomatic, apyrexial and haemodynamically stable after the procedure and was discharged after 48 h of observation. Follow up abdominal CT scan at 3 months confirmed an occluded aneurysm (Fig. 2B) with infraction of approximately 50% of the spleen.
3. Discussion All symptomatic SAAs need to be treated. However, there is no consensus of the timing of treatment of asymptomatic SAAs. Nevertheless, it is generally advised that any aneurysms >2 cm in diameter should be treated [12,13]. In addition, due to an increased risk of rupture in pregnancy with associated high foetal and maternal mortality and relatively
N.V.G. Jayanthi et al. / European Journal of Radiology Extra 61 (2007) 65–68
Fig. 2. CT abdomen 1-day post-embolisation demonstrated air bubble in the aneurysm, which probably was introduced during the procedure. There was an area of low attenuation of about 30–40% which was exaggerated in post-contrast images (A). Contrast CT scan after 3 months demonstrates exclusion of the aneurysm with about 50% of the spleen well perfused (B).
low post-operative morbidity, SAAs in young (childbearing age) and pregnant women should be promptly treated [2,4]. SAAs in all the patients undergoing liver transplants should also be treated [13] due to an increased incidence of rupture. SAAs can be treated either surgically (open or laparoscopic) [14] or endovascularly. One of the important features of SAAs that influence the mode of treatment is its anatomy [2,4,15]. Proximal aneurysms can be treated by ligation or aneurysmectomy. However, most of the SAAs occur in the distal third of the splenic artery and such aneurysms are best treated by resection of both the aneurysm and spleen [8,12]. Distal lesions can also be treated by means of endovascular embolisation. In most of the cases, treatment of a SAA is associated with a significant loss of the splenic function. Even though, splenectomy is performed regularly for various reasons, it is important to preserve splenic function. Patients after splenectomy are prone to bacterial infections. Post-splenectomy sepsis is a serious overwhelming infection following splenectomy. Impaired bacterial clearance, mainly of encapsulated
67
Gram-positive bacteria such as Streptococcus pneumoniae is believed to cause such an infection and occurs in about 0.6% of children and 0.3% of adults [16]. In order to prevent such an infection, patients are started on long-term antibiotics and vaccines. In view of the importance of the splenic function and post-splenectomy syndrome, distal SAAs have been treated surgically with excision and end to end anatomosis of the splenic artery [17] and stent grafting [1,18], thus preserving splenic function. Treatment of a distal SAA by means of endovascular embolisation can be an ideal option, especially when the aneurysm is arising from a splenic artery branch. In the case presented in this report, the aneurysm was originating from the superior segmental branch of the splenic artery. Examination of the proximal celiac axis was normal. There was no communication between the aneurysm and the inferior segmental branch of splenic artery. The superior segmental branch of the splenic artery was sub-selectively catheterised and then embolised resulting in successful exclusion of the aneurysm, which may otherwise have required a more invasive procedure and may have required splenectomy [15] due to the distal nature of the aneurysm. The patient in this case report did not demonstrate any clinical signs of infection during follow up. Partial or sub-total splenectomy has been performed successfully for various haematological conditions [19–21]. In these series up to 80–90% was resected. It has been demonstrated that the splenic function was preserved despite partial or sub-total splenectomy. Follow up CT scan at 3 months demonstrated that up to a 50% of the spleen was well perfused.
4. Conclusion Although doubts have been raised regarding endovascular treatment for visceral artery aneurysms [15], this case report clearly demonstrates that a distal splenic artery aneurysm arising from a splenic artery branch can be successfully treated with sub-selective endovascular embolisation. Importantly, most of the spleen can be preserved, thus precluding long-term morbidity that is associated with the loss of splenic function and avoiding the need for long-term vaccines and antibiotics.
References [1] Arepally A, Dagli M, Hofmann LV, Kim HS, Cooper M, Klein A. Treatment of splenic artery aneurysm with use of a stent-graft. J Vasc Interv Radiol 2002;13(6):631–3. [2] Selo-Ojeme DO, Welch CC. Review: spontaneous rupture of splenic artery aneurysm in pregnancy. Eur J Obstet Gynecol Reprod Biol 2003;109(2):124–7. [3] DeRoover A, Sudan D. Treatment of multiple aneurysms of the splenic artery after liver transplantation by percutaneous embolization and laparoscopic splenectomy. Transplantation 2001;72(5):956–8.
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[4] Hallett Jr JW. Splenic artery aneurysms. Semin Vasc Surg 1995; 8(4):321–6. [5] Lee PC, Rhee RY, Gordon RY, Fung JJ, Webster MW. Management of splenic artery aneurysms: the significance of portal and essential hypertension. J Am Coll Surg 1999;189(5):483–90. [6] Stanley JC, Fry WJ. Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 1974;76(6):898–909. [7] Gaglio PJ, Regenstein F, Slakey D, et al. Alpha-1 antitrypsin deficiency and splenic artery aneurysm rupture: an association? Am J Gastroenterol 2000;95(6):1531–4. [8] Messina LM, Shanley CJ. Visceral artery aneurysms. Surg Clin North Am 1997;77(2):425–42. [9] Brockman RL. Aneurysm of splenic artery. Br J Surg 1929; 30(17):692–3. [10] Hillemanns P, Knitza R, Muller-Hocker J. Rupture of splenic artery aneurysm in a pregnant patient with portal hypertension. Am J Obstet Gynecol 1996;174(5):1665–6. [11] Pomerantz RA, Eckhauser FE, Strodel WE, Knol JA, Turcotte JG. Splenic aneurysm rupture in cirrhotic patients. Arch Surg 1986;121(9):1095–6. [12] de Perrot M, Buhler L, Deleaval J, Borisch B, Mentha G, Morel P. Management of true aneurysms of the splenic artery. Am J Surg 1998;175(6):466–8. [13] Mattar SG, Lumsden AB. The management of splenic artery aneurysms: experience with 23 cases. Am J Surg 1995;169(6):580–4.
[14] de Csepel J, Quinn T, Gagner M. Laparoscopic exclusion of a splenic artery aneurysm using a lateral approach permits preservation of the spleen. Surg Laparosc Endosc Percutan Technol 2001;11(3):221–4. [15] Saltzberg SS, Maldonado TS, Lamparello PJ, et al. Is endovascular therapy the preferred treatment for all visceral artery aneurysms? Ann Vasc Surg 2005;19(4):507–15. [16] Okinaga K, Giebink GS, Rich RH, Baesl TJ, Krishnanaik D, Leonard AS. The effect of partial splenectomy on experimental pneumococcal bacteremia in an animal model. J Pediatr Surg 1981;16(5):717–24. [17] Chakfe N, Mantz F, Kretz JG, Gasser B, Loson R, Eisenmann B. Treatment of a distal splenic artery aneurysm with splenic conservation. A case report. J Cardiovasc Surg (Torino) 1993;34(6):503–6. [18] Moyer HR, Hiramoto JS, Wilson MW, Reddy P, Messina LM, Schneider DB. Stent-graft repair of a splenic artery aneurysm. J Vasc Surg 2005;41(5):897. [19] Rice HE, Oldham KT, Hillery CA, Skinner MA, 0’Hara SM, Ware RE. Clinical and haemotological benefits of partial splenectomy for congenital hemolytic anaemias in children. Ann Surg 2003;237(2): 281–8. [20] Bader-Meunier B, Gauthier F, Archambaud F, et al. Long-term evaluation of the beneficial effect of subtotal splenectomy for management of hereditary spherocytosis. Blood 2001;97(2):399–403. [21] Stoehr GA, Stauffer UG, Eber SW. Near-total splenectomy: a new technique for the management of hereditary spherocytosis. Ann Surg 2005;241(1):40–7.