weekly_question 14/7/2024

[Admin]

A 9-month-old child undergoes removal of a central abdominal neuroblastoma. Postoperatively, she develops accumulation of fluid in her abdomen. The fluid has 90% lymphocytes and high chylomicron levels. She undergoes abdominal drain placement due to respiratory compromise. She receives octreotide infusion and TPN administration. Six weeks later, the patient continues to have 40-50 ml/kg/day of chylous ascites, persistent lymphopenia, and hypoalbuminemia. The best option to manage persistent chylous ascites is

A abdominal exploration with direct ligation of lymphatic vessels

B percutaneous lymphatic duct embolization

C percutaneous retroperitoneal injection of thrombin

D direct ligation of thoracic duct at the neck

E low dose abdominal radiation DISCUSSION

[Admin]

Correct answer
B percutaneous lymphatic duct embolization

Percutaneous manipulation of the thoracic duct has been described to treat both traumatic and nontraumatic leaks in the lymphatic system. Two methods have been described: thoracic duct embolization (TDE) designed to directly stop leaks at the site of injury and thoracic duct disruption (TDD) that causes disruption of the thoracic duct to create a controlled leak and inflammatory reaction in the retroperitoneum, leading to lymphatic collateralization and diversion of flow from the main thoracic duct.

Numerous approaches to embolization have been described including intranodal lymphangiography, transabdominal, and retrograde catheterization of the thoracic duct. The first step is to identify the leak in the lymphatic system which may be accomplished with magnetic resonance ductography in non-traumatic lymph leaks or lymphangiography. A classic method of lymphangiography starts by injecting a small volume of isosulfan blue (0.2 ml of 1% isosulfan blue mixed 1:1 with lidocaine) in the web spaces between the toes. After 5-10 minutes, an incision is made in the upper dorsal foot to look for the blue lymphatic vessel. Another more contemporary method is direct lymph node injection of the groin. The lymph node/ lymphatic vessel is carefully cannulated with a very small (30 gauge) needle. Five mL of ethiodized oil is injected using a lymphatic pump. The flow of the lymph is followed to the lumbar spine L1-L2 level where the flow becomes less defined due to intermixing with splanchnic lymph. In this region, if the cisterna chyli or one main abdominal lymphatic vessels are identified, manipulation with guidewires or direct embolization of the leak is performed, depending on the clinical need.

If the leak is identified, embolization using cyanoacrylate glue and/or microcoils has been described. Collectively, TDE has higher clinical success treating traumatic compared with nontraumatic chyle leaks. Overall, acute complications associated with TDE are minor and generally self-limited and are estimated at 2% to 6% range.

Long-term complications may be seen in up to 14% of patients and may include leg swelling, abdominal swelling, or chronic diarrhea.

Surgical ligation of the thoracic duct and its branches is the traditional surgical option for persistent lymphatic leaks and is reported to be 80% successful. However, in institutions where percutaneous intervention involving the lymphatic system is available, this approach has evolved to be the first line therapy for lymphatic leaks. Direct thoracic duct ligation at the neck would likely exacerbate chylous ascites. Open and laparoscopic administration of fibrin glue have been described during surgical procedures to control lymph leaks when a specific leaking lymphatic vessel is not identified. The results of the fibrin glue approach has not been systematically reported. Abdominal radiation has not been utilized for lymphatic leaks in the pediatric population, but a case has been reported recently in an adult patient.

[Ismailmohamed]

A

[Bilal]

A

[Admin]

Correct answer
B percutaneous lymphatic duct embolization

Percutaneous manipulation of the thoracic duct has been described to treat both traumatic and nontraumatic leaks in the lymphatic system. Two methods have been described: thoracic duct embolization (TDE) designed to directly stop leaks at the site of injury and thoracic duct disruption (TDD) that causes disruption of the thoracic duct to create a controlled leak and inflammatory reaction in the retroperitoneum, leading to lymphatic collateralization and diversion of flow from the main thoracic duct.

Numerous approaches to embolization have been described including intranodal lymphangiography, transabdominal, and retrograde catheterization of the thoracic duct. The first step is to identify the leak in the lymphatic system which may be accomplished with magnetic resonance ductography in non-traumatic lymph leaks or lymphangiography. A classic method of lymphangiography starts by injecting a small volume of isosulfan blue (0.2 ml of 1% isosulfan blue mixed 1:1 with lidocaine) in the web spaces between the toes. After 5-10 minutes, an incision is made in the upper dorsal foot to look for the blue lymphatic vessel. Another more contemporary method is direct lymph node injection of the groin. The lymph node/ lymphatic vessel is carefully cannulated with a very small (30 gauge) needle. Five mL of ethiodized oil is injected using a lymphatic pump. The flow of the lymph is followed to the lumbar spine L1-L2 level where the flow becomes less defined due to intermixing with splanchnic lymph. In this region, if the cisterna chyli or one main abdominal lymphatic vessels are identified, manipulation with guidewires or direct embolization of the leak is performed, depending on the clinical need.

If the leak is identified, embolization using cyanoacrylate glue and/or microcoils has been described. Collectively, TDE has higher clinical success treating traumatic compared with nontraumatic chyle leaks. Overall, acute complications associated with TDE are minor and generally self-limited and are estimated at 2% to 6% range.

Long-term complications may be seen in up to 14% of patients and may include leg swelling, abdominal swelling, or chronic diarrhea.

Surgical ligation of the thoracic duct and its branches is the traditional surgical option for persistent lymphatic leaks and is reported to be 80% successful. However, in institutions where percutaneous intervention involving the lymphatic system is available, this approach has evolved to be the first line therapy for lymphatic leaks. Direct thoracic duct ligation at the neck would likely exacerbate chylous ascites. Open and laparoscopic administration of fibrin glue have been described during surgical procedures to control lymph leaks when a specific leaking lymphatic vessel is not identified. The results of the fibrin glue approach has not been systematically reported. Abdominal radiation has not been utilized for lymphatic leaks in the pediatric population, but a case has been reported recently in an adult patient.