Laparoscopic treatment of a patent ductus venosus and the use of indocyanine green to monitor perioperative hepatic function

Laparoscopic treatment of a patent ductus venosus and the use of indocyanine green to monitor... Patent ductus venosus (PDV) is an uncommon but important congenital portocaval shunt that can lead to numerous compli- cations if untreated. This case describes the successful management of a 17-year-old male with symptomatic PDV. Doppler ultrasonography and contrast-enhanced computed tomography (CT) confirmed a large communication between the left por- tal vein and the inferior vena cava. Angiography demonstrated a large and high flow PDV which precluded its therapeutic embolization. Based on these findings, laparoscopic closure of the PDV was elected and successfully performed. Perioperative indocyanine green (ICG) clearance was performed and marked improvement was observed following the occlu- sion of the PDV. The patient showed immediate resolution of symptoms post-operatively and remains asymptomatic 2 years after his surgery. Laparoscopic approach to the management of PDV is feasible. ICG clearance, for the first time, was demonstrated in this setting to be a useful and rapid bedside test for the real-time assessment of liver function. INTRODUCTION and hepatopulmonary syndrome [3]. Taking into the account The ductus venosus (DV) arises from the posterior aspect of the of these factors, the placement of an endoluminal occlusive left portal vein and passes superolaterally to join the left hep- stent or even surgical occlusion (ligation/division/stapling) of atic vein. During foetal development, the DV shunts oxyge- the shunt can be attempted to minimize the complications of nated blood away from the liver. Complete closure normally PDV [4]. occurs 17 days after birth [1]. The remnant ligamentum veno- The evaluation of hepatic function can be performed by com- sum becomes fibrotic and lies within the fissure separating the paring serum ammonia levels and liver biochemistry before and caudate and the left lobe of the liver. This structure that leads after the procedure. However, such tests cannot be readily per- to the left hepatic vein is also a critical landmark in split liver formed intra-operatively. Indocyanine green (ICG) is a non-toxic transplantation [2]. fluorescent dye that is exclusively excreted by the liver [5]. The Complications of a Patent DV (PDV) include encephalop- rate of which ICG is removed from the circulation after intraven- athy, fatty infiltration of the liver, focal nodular hyperplasia ous injection enables the quantification of hepatic function. ICG Received: November 21, 2017. Accepted: February 15, 2018 Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author(s) 2018. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/ licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 2 M.V. Perini et al. clearance is measured as plasma disappearance rate (PDR) and Pre-operative blood tests showed normal liver biochemistry retention after 15 min (R15). The rapid and non-invasive nature and post-prandial hyperammonaenia (162 μmol/L: normal of using ICG to quantify hepatic function has attracted signifi- 16–60 μmol/L). Doppler ultrasound and computed tomography cant interests in many aspects of hepatic surgery [6, 7]. Its cur- (CT) demonstrated a large communication between the left por- rent role in the assessment of shunts like PDV is unclear and tal vein and the left hepatic vein with a patent and hypoplastic has not been reported. portal bed (Fig. 1a). Owing to the calibre and flow of the shunt, Here, we describe the second case in the English literature endovascular occlusion was not feasible (Fig. 2). Surgical treat- of laparoscopic treatment of PDV and the first case in which ment by a two-stage laparoscopic approach (partial occlusion intra-operative assessment of liver function with ICG was followed by division) was subsequently planned. Pre-operative performed. ICG clearance was measured as per institutional protocol (PDR: −1 5.5% min and R15:43.8%) [6]. Ports were placed as followed: 10 mm port at the umbilicus, CASE REPORT 10 mm port in the left mid anterior clavicular line, 5 mm in the A 17-year-old male patient was referred for the assessment of right upper quadrant and 5 mm incision in the sub-xyphoid hepatic encephalopathy associated with fine tremors, somno- region for the Nathanson liver retractor (Cook Medical, USA). lence and attention deficit on a background of recently diag- The liver was normal with no evidence of portal hyperten- sion. Laparoscopic intra-operative ultrasound (IOUS) showed a nosed PDV. Figure 1: Radiological assessment of the patent ductus venosus (PDV) by (a) computed tomography and (b) digital subtraction angiography. Black arrow: PDV traversing towards the inferior vena cava. Figure 2: Laparoscopic view of (a) gastro-hepatic ligament, (b) patent ductus venosus (PDV), (c) loop encircling the PDV with a vascular clamp occluding the PDV and (d) partial occlusion of the PDV with tightened vessel loop secured with surgical clips. White arrow, PDV; green arrow, surgical clamp used for temporary occlusion of the PDV; #, retracted left lobe of the liver. Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 ICG in the laparoscopic treatment of PDV 3 patent portal vasculature. The gastro-hepatic ligament was divided close to the liver to expose the caudate lobe and the PDV (Fig. 2a). The PDV was subsequently encircled with a vessel loop (Fig. 2b). The PDV was temporarily clamped and IOUS was performed to assess the intra-hepatic portal vasculature (Fig. 2c). The portal vasculature remained patent and the splanchnic vasculature did not demonstrate acute portal hypertension. ICG clearance was −1 repeated (PDR: 11.9% min and R15: 16.8%). The decision was undertaken to partially occlude the PDV to minimize the risks of mesenteric congestion or portal venous thrombosis. The vessel loop was tightened and secured with surgical clips and left in-situ, with a view to divide the PDV at a later stage (Fig. 2d). After partial occlusion, ICG clearance was −1 repeated (PDR: 19.5% min and R15: 5.4%). Day 1 post-operatively, the patient remained well and his Figure 3: Perioperative measurements of indocyanine green (ICG) clearance is symptoms continued to improve. His ammonia levels normalized effective for the intra-operative evaluation of hepatic function. ICG-PDR, indo- −1 to 43 μmol/L. ICG clearance was assessed (PDR: 14.2% min and cyanine green plasma disappearance rate; ICG-R15, indocyanine green reten- tion ratio after 15 min. R15: 11.9%). Doppler ultrasound confirmed portal venous patency and a completely occluded PDV. In view of this finding, therapeutic anticoagulation was initiated to minimize the risks of portal vein Non-invasive measurements of ICG clearance is increasingly thrombosis. The patient was discharged home after 3 days. being used to assess hepatic function. In this case, we have At 3 months, a quad-phase CT of the liver demonstrated an also demonstrated the practicality of ICG clearance in the rapid occluded PDV with patent extra- and intra-hepatic portal vas- intra-operative assessment of hepatic function after partial culature. An increase in liver volume from 830 to 1468 mL was occlusion of the shunt (Fig. 3). also observed on CT volumetry analysis. Anticoagulation was In conclusion, a minimally invasive laparoscopic approach ceased. The patient remains asymptomatic at 24 months. is safe and feasible for the treatment of PDV. The consideration Based on these findings, the initial plan to divide the PDV at a of a two-stage approach may be useful to manage PDV. In add- later stage was no longer required. ition, the use of perioperative ICG clearances is feasible to rap- idly evaluate the successful treatment of PDV. DISCUSSION ACKNOWLEDGEMENTS Reported treatments of PDV include radiological occlusion, surgi- cal ligation and liver transplantation. The use of these procedures, No acknowledgements. to date, remains heterogeneous owing to the rarity of the condi- tion [8]. CONFLICT OF INTEREST STATEMENT Shunt occlusion is the treatment of choice for PDV and this can be performed through an endovascular or a surgical approach. No competing financial interests. A key complication that can occur post-operatively is portal ven- ous thrombosis. This is critical in patients with hypoplastic intra- REFERENCES hepatic portal vasculature, whereby the sudden occlusion of the shunt can lead acute portal hypertension, gastrointestinal bleed- 1. Meyer WW, Lind J. The ductus venosus and the mechanism ing and intestinal infarct [8]. of its closure. Arch Dis Child 1966;41:597–605. Laparoscopic treatment of other porto-systemic shunts has 2. Majno PE, Mentha G, Morel P, Segalin A, Azoulay D, Oberholzer been reported [9]. However, only one case of PDV occlusion by a J, et al. Arantius’ ligament approach to the left hepatic vein laparoscopic approach has been reported, of which the patient and to the common trunk. JAm CollSurg 2002;195:737–9. developed portal venous thrombosis that required thromboly- 3. Tercier S, Delarue A, Rouault F, Roman C, Breaud J, Petit P. sis [10]. Congenital portocaval fistula associated with hepatopul- In order to minimize the risks of complications in this case, monary syndrome: ligation vs liver transplantation. J Pediatr a two-stage procedure was initially planned to partially occlude Surg 2006;41:e1–3. the shunt first, and divide the shunt at a later stage. It was pos- 4. Blanc T, Guerin F, Franchi-Abella S, Jacquemin E, Pariente tulated that this will allow the portal vasculature to adapt to D, Soubrane O, et al. Congenital portosystemic shunts in the increased portal flow changes. This manoeuvre is con- children: a new anatomical classification correlated with sidered reversible and upon occurrence of catastrophic post- surgical strategy. Ann Surg 2014;260:188–98. operative complications, the vessel loop (occluding the PDV) 5. Imamura H, Sano K, Sugawara Y, Kokudo N, Makuuchi M. can be readily removed. Assessment of hepatic reserve for indication of hepatic As there was no PDV flow documented on Doppler ultra- resection: decision tree incorporating indocyanine green sound on Day 1 post-operatively, therapeutic anticoagulation test. J Hepatobiliary Pancreat Surg 2005;12:16–22. was commenced to reduce the overall risks of portal venous 6. LauL,ChristophiC,Nikfarjam M, StarkeyG, Goodwin M, thrombosis. Since the patient remained asymptomatic and the Weinberg L, et al. Assessment of liver remnant using ICG clear- PDV remained occluded without any evidence of portal venous ance intraoperatively during vascular exclusion: early experi- thrombosis at 3 months, it was thus considered that the second ence with the ALIIVE technique. HPB Surg 2015;2015:757052. stage of the procedure for ligation and division of the PDV was 7. Thomas MN, Weninger E, Angele M, Bosch F, Pratschke S, no longer necessary. Andrassy J, et al. Intraoperative simulation of remnant liver Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 4 M.V. Perini et al. function during anatomic liver resection with indocyanine 9. Kimura T, SohH,HasegawaT,SasakiT,KurodaS,YuriE,etal. green clearance (LiMON) measurements. HPB (Oxford) 2015; Laparoscopic correction of congenital portosystemic shunt in 17:471–6. children. Surg Laparosc Endosc Percutan Tech 2004;14:285–8. 8. Kamimatsuse A, Onitake Y, Kamei N, Tajima G, Sakura N, 10. Hara Y, Sato Y, Yamamoto S, Oya H, Igarashi M, Abe S, et al. Sueda T, et al. Surgical intervention for patent ductus ven- Successful laparoscopic division of a patent ductus ven- osus. Pediatr Surg Int 2010;26:1025–30. osus: report of a case. Surg Today 2013;43:434–8. Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Surgical Case Reports Oxford University Press

Laparoscopic treatment of a patent ductus venosus and the use of indocyanine green to monitor perioperative hepatic function

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Abstract

Patent ductus venosus (PDV) is an uncommon but important congenital portocaval shunt that can lead to numerous compli- cations if untreated. This case describes the successful management of a 17-year-old male with symptomatic PDV. Doppler ultrasonography and contrast-enhanced computed tomography (CT) confirmed a large communication between the left por- tal vein and the inferior vena cava. Angiography demonstrated a large and high flow PDV which precluded its therapeutic embolization. Based on these findings, laparoscopic closure of the PDV was elected and successfully performed. Perioperative indocyanine green (ICG) clearance was performed and marked improvement was observed following the occlu- sion of the PDV. The patient showed immediate resolution of symptoms post-operatively and remains asymptomatic 2 years after his surgery. Laparoscopic approach to the management of PDV is feasible. ICG clearance, for the first time, was demonstrated in this setting to be a useful and rapid bedside test for the real-time assessment of liver function. INTRODUCTION and hepatopulmonary syndrome [3]. Taking into the account The ductus venosus (DV) arises from the posterior aspect of the of these factors, the placement of an endoluminal occlusive left portal vein and passes superolaterally to join the left hep- stent or even surgical occlusion (ligation/division/stapling) of atic vein. During foetal development, the DV shunts oxyge- the shunt can be attempted to minimize the complications of nated blood away from the liver. Complete closure normally PDV [4]. occurs 17 days after birth [1]. The remnant ligamentum veno- The evaluation of hepatic function can be performed by com- sum becomes fibrotic and lies within the fissure separating the paring serum ammonia levels and liver biochemistry before and caudate and the left lobe of the liver. This structure that leads after the procedure. However, such tests cannot be readily per- to the left hepatic vein is also a critical landmark in split liver formed intra-operatively. Indocyanine green (ICG) is a non-toxic transplantation [2]. fluorescent dye that is exclusively excreted by the liver [5]. The Complications of a Patent DV (PDV) include encephalop- rate of which ICG is removed from the circulation after intraven- athy, fatty infiltration of the liver, focal nodular hyperplasia ous injection enables the quantification of hepatic function. ICG Received: November 21, 2017. Accepted: February 15, 2018 Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author(s) 2018. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/ licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 2 M.V. Perini et al. clearance is measured as plasma disappearance rate (PDR) and Pre-operative blood tests showed normal liver biochemistry retention after 15 min (R15). The rapid and non-invasive nature and post-prandial hyperammonaenia (162 μmol/L: normal of using ICG to quantify hepatic function has attracted signifi- 16–60 μmol/L). Doppler ultrasound and computed tomography cant interests in many aspects of hepatic surgery [6, 7]. Its cur- (CT) demonstrated a large communication between the left por- rent role in the assessment of shunts like PDV is unclear and tal vein and the left hepatic vein with a patent and hypoplastic has not been reported. portal bed (Fig. 1a). Owing to the calibre and flow of the shunt, Here, we describe the second case in the English literature endovascular occlusion was not feasible (Fig. 2). Surgical treat- of laparoscopic treatment of PDV and the first case in which ment by a two-stage laparoscopic approach (partial occlusion intra-operative assessment of liver function with ICG was followed by division) was subsequently planned. Pre-operative performed. ICG clearance was measured as per institutional protocol (PDR: −1 5.5% min and R15:43.8%) [6]. Ports were placed as followed: 10 mm port at the umbilicus, CASE REPORT 10 mm port in the left mid anterior clavicular line, 5 mm in the A 17-year-old male patient was referred for the assessment of right upper quadrant and 5 mm incision in the sub-xyphoid hepatic encephalopathy associated with fine tremors, somno- region for the Nathanson liver retractor (Cook Medical, USA). lence and attention deficit on a background of recently diag- The liver was normal with no evidence of portal hyperten- sion. Laparoscopic intra-operative ultrasound (IOUS) showed a nosed PDV. Figure 1: Radiological assessment of the patent ductus venosus (PDV) by (a) computed tomography and (b) digital subtraction angiography. Black arrow: PDV traversing towards the inferior vena cava. Figure 2: Laparoscopic view of (a) gastro-hepatic ligament, (b) patent ductus venosus (PDV), (c) loop encircling the PDV with a vascular clamp occluding the PDV and (d) partial occlusion of the PDV with tightened vessel loop secured with surgical clips. White arrow, PDV; green arrow, surgical clamp used for temporary occlusion of the PDV; #, retracted left lobe of the liver. Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 ICG in the laparoscopic treatment of PDV 3 patent portal vasculature. The gastro-hepatic ligament was divided close to the liver to expose the caudate lobe and the PDV (Fig. 2a). The PDV was subsequently encircled with a vessel loop (Fig. 2b). The PDV was temporarily clamped and IOUS was performed to assess the intra-hepatic portal vasculature (Fig. 2c). The portal vasculature remained patent and the splanchnic vasculature did not demonstrate acute portal hypertension. ICG clearance was −1 repeated (PDR: 11.9% min and R15: 16.8%). The decision was undertaken to partially occlude the PDV to minimize the risks of mesenteric congestion or portal venous thrombosis. The vessel loop was tightened and secured with surgical clips and left in-situ, with a view to divide the PDV at a later stage (Fig. 2d). After partial occlusion, ICG clearance was −1 repeated (PDR: 19.5% min and R15: 5.4%). Day 1 post-operatively, the patient remained well and his Figure 3: Perioperative measurements of indocyanine green (ICG) clearance is symptoms continued to improve. His ammonia levels normalized effective for the intra-operative evaluation of hepatic function. ICG-PDR, indo- −1 to 43 μmol/L. ICG clearance was assessed (PDR: 14.2% min and cyanine green plasma disappearance rate; ICG-R15, indocyanine green reten- tion ratio after 15 min. R15: 11.9%). Doppler ultrasound confirmed portal venous patency and a completely occluded PDV. In view of this finding, therapeutic anticoagulation was initiated to minimize the risks of portal vein Non-invasive measurements of ICG clearance is increasingly thrombosis. The patient was discharged home after 3 days. being used to assess hepatic function. In this case, we have At 3 months, a quad-phase CT of the liver demonstrated an also demonstrated the practicality of ICG clearance in the rapid occluded PDV with patent extra- and intra-hepatic portal vas- intra-operative assessment of hepatic function after partial culature. An increase in liver volume from 830 to 1468 mL was occlusion of the shunt (Fig. 3). also observed on CT volumetry analysis. Anticoagulation was In conclusion, a minimally invasive laparoscopic approach ceased. The patient remains asymptomatic at 24 months. is safe and feasible for the treatment of PDV. The consideration Based on these findings, the initial plan to divide the PDV at a of a two-stage approach may be useful to manage PDV. In add- later stage was no longer required. ition, the use of perioperative ICG clearances is feasible to rap- idly evaluate the successful treatment of PDV. DISCUSSION ACKNOWLEDGEMENTS Reported treatments of PDV include radiological occlusion, surgi- cal ligation and liver transplantation. The use of these procedures, No acknowledgements. to date, remains heterogeneous owing to the rarity of the condi- tion [8]. CONFLICT OF INTEREST STATEMENT Shunt occlusion is the treatment of choice for PDV and this can be performed through an endovascular or a surgical approach. No competing financial interests. A key complication that can occur post-operatively is portal ven- ous thrombosis. This is critical in patients with hypoplastic intra- REFERENCES hepatic portal vasculature, whereby the sudden occlusion of the shunt can lead acute portal hypertension, gastrointestinal bleed- 1. Meyer WW, Lind J. The ductus venosus and the mechanism ing and intestinal infarct [8]. of its closure. Arch Dis Child 1966;41:597–605. Laparoscopic treatment of other porto-systemic shunts has 2. Majno PE, Mentha G, Morel P, Segalin A, Azoulay D, Oberholzer been reported [9]. However, only one case of PDV occlusion by a J, et al. Arantius’ ligament approach to the left hepatic vein laparoscopic approach has been reported, of which the patient and to the common trunk. JAm CollSurg 2002;195:737–9. developed portal venous thrombosis that required thromboly- 3. Tercier S, Delarue A, Rouault F, Roman C, Breaud J, Petit P. sis [10]. Congenital portocaval fistula associated with hepatopul- In order to minimize the risks of complications in this case, monary syndrome: ligation vs liver transplantation. J Pediatr a two-stage procedure was initially planned to partially occlude Surg 2006;41:e1–3. the shunt first, and divide the shunt at a later stage. It was pos- 4. Blanc T, Guerin F, Franchi-Abella S, Jacquemin E, Pariente tulated that this will allow the portal vasculature to adapt to D, Soubrane O, et al. Congenital portosystemic shunts in the increased portal flow changes. This manoeuvre is con- children: a new anatomical classification correlated with sidered reversible and upon occurrence of catastrophic post- surgical strategy. Ann Surg 2014;260:188–98. operative complications, the vessel loop (occluding the PDV) 5. Imamura H, Sano K, Sugawara Y, Kokudo N, Makuuchi M. can be readily removed. Assessment of hepatic reserve for indication of hepatic As there was no PDV flow documented on Doppler ultra- resection: decision tree incorporating indocyanine green sound on Day 1 post-operatively, therapeutic anticoagulation test. J Hepatobiliary Pancreat Surg 2005;12:16–22. was commenced to reduce the overall risks of portal venous 6. LauL,ChristophiC,Nikfarjam M, StarkeyG, Goodwin M, thrombosis. Since the patient remained asymptomatic and the Weinberg L, et al. Assessment of liver remnant using ICG clear- PDV remained occluded without any evidence of portal venous ance intraoperatively during vascular exclusion: early experi- thrombosis at 3 months, it was thus considered that the second ence with the ALIIVE technique. HPB Surg 2015;2015:757052. stage of the procedure for ligation and division of the PDV was 7. Thomas MN, Weninger E, Angele M, Bosch F, Pratschke S, no longer necessary. Andrassy J, et al. Intraoperative simulation of remnant liver Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018 4 M.V. Perini et al. function during anatomic liver resection with indocyanine 9. Kimura T, SohH,HasegawaT,SasakiT,KurodaS,YuriE,etal. green clearance (LiMON) measurements. HPB (Oxford) 2015; Laparoscopic correction of congenital portosystemic shunt in 17:471–6. children. Surg Laparosc Endosc Percutan Tech 2004;14:285–8. 8. Kamimatsuse A, Onitake Y, Kamei N, Tajima G, Sakura N, 10. Hara Y, Sato Y, Yamamoto S, Oya H, Igarashi M, Abe S, et al. Sueda T, et al. Surgical intervention for patent ductus ven- Successful laparoscopic division of a patent ductus ven- osus. Pediatr Surg Int 2010;26:1025–30. osus: report of a case. Surg Today 2013;43:434–8. Downloaded from https://academic.oup.com/jscr/article-abstract/2018/2/rjy026/4898379 by Ed 'DeepDyve' Gillespie user on 16 March 2018

Journal

Journal of Surgical Case ReportsOxford University Press

Published: Feb 1, 2018

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