1404
’
Commentary: Lymphatic Interventions in IR
13. Boffa D, Sands M, Rice T, et al. A critical evaluation of a percutaneous diagnostic and treatment strategy for chylothorax after thoracic surgery. Eur J Cardiothorac Surg 2008; 33:435–439. 14. Itkin M, Kucharczuk J, Kwak A, Trerotola S, Kaiser L. Nonoperative thoracic duct embolization for traumatic thoracic duct leak: experience in 109 patients. J Thorac Cardiovasc Surg 2010; 139:584–590. 15. Mittleider D, Dykes TA, Cicuto KP, Amberson SM, Leusner CR. Retrograde cannulation of the thoracic duct and embolization of the cisterna chyli in the treatment of chylous ascites. J Vasc Intervent Radiol 2008; 19:285–290. 16. Sacks D, McClenny TE, Cardella JF, Lewis CA. Society of Interventional Radiology Clinical Practice Guidelines. J Vasc Interv Radiol 2003; 14 (suppl):S199–S202.
ltkin
’
JVIR
17. Gómez FM, Martínez-Rodrigo J, Martí-Bonmatí L, et al. Transnodal lymphangiography in the diagnosis and treatment of genital lymphedema. Cardiovasc Intervent Radiol 2012; 35:1488–1491. 18. Nadolski GJ, Itkin M. Thoracic duct embolization for nontraumatic chylous effusion: experience in 34 patients. Chest 2013; 143: 158–163. 19. Matsumoto T, Yamagami T, Kato T, et al. The effectiveness of lymphangiography as a treatment method for various chyle leakages. Br J Radiol 2009; 82:286–290. 20. Laslett D, Trerotola SO, Itkin M. Delayed complications following technically successful thoracic duct embolization. J Vasc Interv Radiol 2012; 23:76–79.
INVITED COMMENTARY
Lymphatic Intervention Is a New Frontier of IR Maxim Itkin, MD ABBREVIATIONS TDD = thoracic duct disruption, TDE = thoracic duct embolization
Since its original description in 1998 by Cope, thoracic duct embolization (TDE) has become the gold standard treatment of traumatic chylothorax. The ability to visualize lymphatic leaks has significantly increased the chances of success of the procedure, and the use of the minimally invasive approach resulted in reduction of complication rates compared with the surgical approach. Chylothorax is considered to be a rare disease, and there is abundant literature with numerous case reports and small case series describing different treatment approaches. However, it is difficult to make any meaningful treatment recommendations based on these anecdotal data. Therefore, the study by Pamarthi et al (1) that summarizes the second largest experience of TDE and thoracic duct disruption (TDD) to treat chylothorax is a valuable addition to the existing body of literature. This article reports the operators’ TDE experience that spans a period of more than 9 years, including the group’s initial experience. The described technical success rate of TDE/TDD was 85%, with failed cases primarily related to failure to perform pedal lymphangiography and poor opacification From the Department of Radiology, Penn Medicine, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104. Received June 5, 2014; final revision received and accepted June 6, 2014. Address correspondence to M.I.; E-mail: [email protected] The author has not identified a conflict of interest. Published by Elsevier, Inc., on behalf of SIR J Vasc Interv Radiol 2014; 25:1404–1405 http://dx.doi.org/10.1016/j.jvir.2014.06.004
of the retroperitoneal lymphatic ducts. Expertise in performance of pedal lymphangiography is a “dying art” in interventional radiology, and it is not surprising that the failure rate was relatively high. Introduction of intranodal lymphangiography (2) can potentially significantly improve the technical success of TDE. Intranodal lymphangiography is technically easy and falls within the skill set of any interventionalist with experience in ultrasonographically guided interventions. Intranodal lymphangiography also improves the opacification of the retroperitoneal lymphatic ducts as a result of the relative proximity of the contrast agent injection point in the groin to the retroperitoneal lymphatic ducts. The most technically challenging component of TDE is being able to access the central lymphatic system, ie, the cisterna chyli or, ideally, the lumbar ducts that lead to the cisterna chyli. It is challenging for the operator to get sufficient experience because of the relative infrequency of this condition. TDD, a less technically challenging alternative to TDE, was used in a significant number of cases in this study (1). Surprisingly, the success rate of TDD was only slightly less than that of TDE (72% vs 55%). This can also be explained by the well known therapeutic effect of lymphangiography alone. Another expected and striking observation is a significantly higher success rate of the treatment of traumatic chylothorax versus nontraumatic chylothorax: 62% vs 13%, respectively. The cause of traumatic chylothorax in most of cases is a leak from the thoracic duct or its tributaries. This injury can be easily visualized with lymphangiography and subsequently treated by
Volume 25
’
Number 9
’
September
’
2014
embolization. During the past few years, we learned that, in nontraumatic chylothorax, the source of the leak does not necessarily originate in the thoracic duct (3). One of the common causes of nontraumatic chylothorax is the passage of chylous ascites into the pleural cavity through the holes in the diaphragm as a result of relative negative pressure in the chest. Another common cause of nontraumatic chylothorax is the leakage of chyle through retroperitoneal or pulmonary lymphatic malformations, such as in the case of lymphangiomatosis, and through the lymphatic collateral vessels that originate below the diaphragm, such as in the example of lymphatic malignancies. Reported complications directly related to TDE are slightly more common in this study (1) than in previous reports, but none of them were of clinical significance. This again confirms the safety of this method. I believe lymphatic interventions represent the new frontier for interventional radiology, and any addition to the body of the literature at this early stage of the field is of paramount importance. During the past several decades, the lymphatic circulation was overlooked and is now frequently referred to as the “forgotten third circulation.” The importance of lymphatic flow was well appreciated from the 1950s to the 1970s in a number of disease processes, including ascites in liver cirrhosis and heart failure (4). Significant animal research was conducted to understand the change in the lymphatic flow in different pathologic conditions and the effect of this alteration on the symptoms. Unfortunately, the abundance of preclinical data was not transferred into
1405
widespread clinical practice, primarily because of a lack of clinical imaging and intervention options. Cope’s groundbreaking work paved the way to the new approach to interventions in the lymphatic system, taking full advantage of minimally invasive approaches. The development of new, technically easier imaging alternatives such as intranodal lymphangiography, noncontrast magnetic resonance imaging technique (5), and contrast-enhanced magnetic resonance lymphangiography technique further advances our understanding of lymphatic flow dynamics and their effect on a variety of disease processes. Given our understanding of the untapped potential for research and clinical applications, we expect that, within a few years, interventional lymphology will become the fastest growing sector of the minimally invasive field.
REFERENCES 1. Pamarthi V, Stecker MS, Schenker MP, et al. Thoracic duct embolization and disruption for treatment of chylous effusions: experience with 105 patients. J Vasc Interv Radiol 2014; 25:1398–1404. 2. Nadolski GJ, Itkin M. Feasibility of ultrasound-guided intranodal lymphangiogram for thoracic duct embolization. J Vasc Interv Radiol 2012; 23: 613–616. 3. Nadolski G, Itkin M. Thoracic duct embolization for the management of chylothoraces. Curr Opin Pulm Med 2013; 19:380–386. 4. Witte MH, Dumont AE, Clauss RH, Rader B, Levine N, Breed ES. Lymph circulation in congestive heart failure: effect of external thoracic duct drainage. Circulation 1969; 39:723–733. 5. Dori Y, Keller MS, Fogel MA, et al. MRI of lymphatic abnormalities after functional single-ventricle palliation surgery. AJR Am J Roentgenol 2014, http://dx.doi.org/10.2214/AJR.13.11797.
’
Commentary: Lymphatic Interventions in IR
13. Boffa D, Sands M, Rice T, et al. A critical evaluation of a percutaneous diagnostic and treatment strategy for chylothorax after thoracic surgery. Eur J Cardiothorac Surg 2008; 33:435–439. 14. Itkin M, Kucharczuk J, Kwak A, Trerotola S, Kaiser L. Nonoperative thoracic duct embolization for traumatic thoracic duct leak: experience in 109 patients. J Thorac Cardiovasc Surg 2010; 139:584–590. 15. Mittleider D, Dykes TA, Cicuto KP, Amberson SM, Leusner CR. Retrograde cannulation of the thoracic duct and embolization of the cisterna chyli in the treatment of chylous ascites. J Vasc Intervent Radiol 2008; 19:285–290. 16. Sacks D, McClenny TE, Cardella JF, Lewis CA. Society of Interventional Radiology Clinical Practice Guidelines. J Vasc Interv Radiol 2003; 14 (suppl):S199–S202.
ltkin
’
JVIR
17. Gómez FM, Martínez-Rodrigo J, Martí-Bonmatí L, et al. Transnodal lymphangiography in the diagnosis and treatment of genital lymphedema. Cardiovasc Intervent Radiol 2012; 35:1488–1491. 18. Nadolski GJ, Itkin M. Thoracic duct embolization for nontraumatic chylous effusion: experience in 34 patients. Chest 2013; 143: 158–163. 19. Matsumoto T, Yamagami T, Kato T, et al. The effectiveness of lymphangiography as a treatment method for various chyle leakages. Br J Radiol 2009; 82:286–290. 20. Laslett D, Trerotola SO, Itkin M. Delayed complications following technically successful thoracic duct embolization. J Vasc Interv Radiol 2012; 23:76–79.
INVITED COMMENTARY
Lymphatic Intervention Is a New Frontier of IR Maxim Itkin, MD ABBREVIATIONS TDD = thoracic duct disruption, TDE = thoracic duct embolization
Since its original description in 1998 by Cope, thoracic duct embolization (TDE) has become the gold standard treatment of traumatic chylothorax. The ability to visualize lymphatic leaks has significantly increased the chances of success of the procedure, and the use of the minimally invasive approach resulted in reduction of complication rates compared with the surgical approach. Chylothorax is considered to be a rare disease, and there is abundant literature with numerous case reports and small case series describing different treatment approaches. However, it is difficult to make any meaningful treatment recommendations based on these anecdotal data. Therefore, the study by Pamarthi et al (1) that summarizes the second largest experience of TDE and thoracic duct disruption (TDD) to treat chylothorax is a valuable addition to the existing body of literature. This article reports the operators’ TDE experience that spans a period of more than 9 years, including the group’s initial experience. The described technical success rate of TDE/TDD was 85%, with failed cases primarily related to failure to perform pedal lymphangiography and poor opacification From the Department of Radiology, Penn Medicine, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104. Received June 5, 2014; final revision received and accepted June 6, 2014. Address correspondence to M.I.; E-mail: [email protected] The author has not identified a conflict of interest. Published by Elsevier, Inc., on behalf of SIR J Vasc Interv Radiol 2014; 25:1404–1405 http://dx.doi.org/10.1016/j.jvir.2014.06.004
of the retroperitoneal lymphatic ducts. Expertise in performance of pedal lymphangiography is a “dying art” in interventional radiology, and it is not surprising that the failure rate was relatively high. Introduction of intranodal lymphangiography (2) can potentially significantly improve the technical success of TDE. Intranodal lymphangiography is technically easy and falls within the skill set of any interventionalist with experience in ultrasonographically guided interventions. Intranodal lymphangiography also improves the opacification of the retroperitoneal lymphatic ducts as a result of the relative proximity of the contrast agent injection point in the groin to the retroperitoneal lymphatic ducts. The most technically challenging component of TDE is being able to access the central lymphatic system, ie, the cisterna chyli or, ideally, the lumbar ducts that lead to the cisterna chyli. It is challenging for the operator to get sufficient experience because of the relative infrequency of this condition. TDD, a less technically challenging alternative to TDE, was used in a significant number of cases in this study (1). Surprisingly, the success rate of TDD was only slightly less than that of TDE (72% vs 55%). This can also be explained by the well known therapeutic effect of lymphangiography alone. Another expected and striking observation is a significantly higher success rate of the treatment of traumatic chylothorax versus nontraumatic chylothorax: 62% vs 13%, respectively. The cause of traumatic chylothorax in most of cases is a leak from the thoracic duct or its tributaries. This injury can be easily visualized with lymphangiography and subsequently treated by
Volume 25
’
Number 9
’
September
’
2014
embolization. During the past few years, we learned that, in nontraumatic chylothorax, the source of the leak does not necessarily originate in the thoracic duct (3). One of the common causes of nontraumatic chylothorax is the passage of chylous ascites into the pleural cavity through the holes in the diaphragm as a result of relative negative pressure in the chest. Another common cause of nontraumatic chylothorax is the leakage of chyle through retroperitoneal or pulmonary lymphatic malformations, such as in the case of lymphangiomatosis, and through the lymphatic collateral vessels that originate below the diaphragm, such as in the example of lymphatic malignancies. Reported complications directly related to TDE are slightly more common in this study (1) than in previous reports, but none of them were of clinical significance. This again confirms the safety of this method. I believe lymphatic interventions represent the new frontier for interventional radiology, and any addition to the body of the literature at this early stage of the field is of paramount importance. During the past several decades, the lymphatic circulation was overlooked and is now frequently referred to as the “forgotten third circulation.” The importance of lymphatic flow was well appreciated from the 1950s to the 1970s in a number of disease processes, including ascites in liver cirrhosis and heart failure (4). Significant animal research was conducted to understand the change in the lymphatic flow in different pathologic conditions and the effect of this alteration on the symptoms. Unfortunately, the abundance of preclinical data was not transferred into
1405
widespread clinical practice, primarily because of a lack of clinical imaging and intervention options. Cope’s groundbreaking work paved the way to the new approach to interventions in the lymphatic system, taking full advantage of minimally invasive approaches. The development of new, technically easier imaging alternatives such as intranodal lymphangiography, noncontrast magnetic resonance imaging technique (5), and contrast-enhanced magnetic resonance lymphangiography technique further advances our understanding of lymphatic flow dynamics and their effect on a variety of disease processes. Given our understanding of the untapped potential for research and clinical applications, we expect that, within a few years, interventional lymphology will become the fastest growing sector of the minimally invasive field.
REFERENCES 1. Pamarthi V, Stecker MS, Schenker MP, et al. Thoracic duct embolization and disruption for treatment of chylous effusions: experience with 105 patients. J Vasc Interv Radiol 2014; 25:1398–1404. 2. Nadolski GJ, Itkin M. Feasibility of ultrasound-guided intranodal lymphangiogram for thoracic duct embolization. J Vasc Interv Radiol 2012; 23: 613–616. 3. Nadolski G, Itkin M. Thoracic duct embolization for the management of chylothoraces. Curr Opin Pulm Med 2013; 19:380–386. 4. Witte MH, Dumont AE, Clauss RH, Rader B, Levine N, Breed ES. Lymph circulation in congestive heart failure: effect of external thoracic duct drainage. Circulation 1969; 39:723–733. 5. Dori Y, Keller MS, Fogel MA, et al. MRI of lymphatic abnormalities after functional single-ventricle palliation surgery. AJR Am J Roentgenol 2014, http://dx.doi.org/10.2214/AJR.13.11797.
