Thoracic Duct Embolization: Analysis of Practice Patterns

Non-conservative Management of Chylothorax

Chylothorax is caused by lymphatic leakage, which can develop after thoracic surgery and is associated with cancer. Although prospective randomized trials have not been performed, radiological interventions have been performed in several cases with persistent chylothorax, adjunct to 2 weeks of conservative management. The success rate of such interventions is diverse due to anatomical variations, although the results are promising. However, in cases of treatment failure after cycles of interventions, a team approach may be necessary to determine whether surgical management is warranted.

Thoracic duct embolization in treating postoperative chylothorax: does bail-out retrograde access improve outcomes?

OBJECTIVES

To evaluate clinical outcomes of thoracic duct embolization (TDE) for the management of postoperative chylothorax with the aid of the bail-out retrograde approach for thoracic duct cannulation (TDC).

MATERIALS AND METHODS

Forty-five patients with postoperative chylothorax underwent Lipiodol lymphangiography (LLG) between February 2016 and November 2019. If targetable central lymphatic vessels were identified in LLG, TDC, a prerequisite for TDE, was attempted. While the conventional antegrade transabdominal approach was the standard TDC method, the retrograde approach was applied as a bail-out method. Embolization, the last step of TDE, was performed after confirming leakages in the trans-TDC catheter lymphangiography. Technical and clinical success rates were determined retrospectively.

RESULTS

TDC was attempted in 40 among 45 patients based on LLG findings. The technical success rate of TDC with the conventional antegrade approach was 78% (31/40). In addition, six more patients were cannulated using the bail-out retrograde approach, which raised the technical success rate to 93% (37/40). While 35 patients underwent embolization (TDE group), ten patients did not (non-TDE group) for the following reasons: (1) lack of targetable lymphatics for TDC in LLG (n = 5), (2) technical failure of TDC (n = 3), and (3) lack of discernible leakages in the transcatheter lymphangiography (n = 2). The clinical success of the TDE group was 89% (31/35), compared with 50% (5/10) of the non-TDE group. One major procedure-related complication was bile peritonitis caused by the needle passage of the distended gallbladder.

CONCLUSIONS

Bail-out retrograde approach for TDC could improve the overall technical success of TDC significantly.

KEY POINTS

• Bail-out retrograde thoracic duct access may improve the overall technical success of thoracic duct access, thus improving the clinical success of thoracic duct embolization.

Radiological management of postoperative lymphorrhea

PURPOSE

Postoperative lymphorrhea can occur after different surgical procedures and may prolong the hospital stay due to the need for specific treatment. In this work, the therapeutic significance of the radiological management of postoperative lymphorrhea was assessed and illustrated.

METHOD

A standardized search of the literature was performed in PubMed applying the Medical Subject Headings (MeSH) term "lymphangiography." For the review, the inclusion criterion was "studies with original data on Lipiodol-based Conventional Lymphangiography (CL) with subsequent Percutaneous Lymphatic Intervention (PLI)." Different exclusion criteria were defined (e.g., studies with <15 patients). The collected data comprised of clinical background and indications, procedural aspects and types of PLI, and outcomes. In the form of a pictorial essay, each author illustrated a clinical case with CL and/or PLI.

RESULTS

Seven studies (corresponding to evidence level 4 [Oxford Centre for Evidence-Based Medicine]) accounting for 196 patients were included in the synthesis and analysis of data. Preceding surgery resulting in postoperative lymphorrhea included different surgical procedures such as extended oncologic surgery or vascular surgery. Central (e.g., chylothorax) and peripheral (e.g., lymphocele) types of postoperative lymphorrhea with a drainage volume of 100-4000 ml/day underwent CL with subsequent PLI. The intervals between "preceding surgery and CL" and between "CL and PLI" were 2-330 days and 0-5 days, respectively. CL was performed before PLI to visualize the lymphatic pathology (e.g., leakage point or inflow lymph ducts), applying fluoroscopy, radiography, and/or computed tomography (CT). In total, seven different types of PLI were identified: (1) thoracic duct (or thoracic inflow lymph duct) embolization, (2) thoracic duct (or thoracic inflow lymph duct) maceration, (3) leakage point direct embolization, (4) inflow lymph node interstitial embolization, (5) inflow lymph duct (other than thoracic) embolization, (6) inflow lymph duct (other than thoracic) maceration, and (7) transvenous retrograde lymph duct embolization. CL-associated and PLI-associated technical success rates were 97-100% and 89-100%, respectively. The clinical success rate of CL and PLI was 73-95%. CL-associated and PLI-associated major complication rates were 0-3% and 0-5%, respectively. The combined CL- and PLI-associated 30-day mortality rate was 0%, and the overall mortality rate was 3% (corresponding to six patients). In the pictorial essay, the spectrum of CL and/or PLI was illustrated.

CONCLUSION

The radiological management of postoperative lymphorrhea is feasible, safe, and effective. Standardized radiological treatments embedded in an interdisciplinary concept are a step towards improving outcomes.

Lymphangiographic Interventions to Manage Postoperative Chylothorax

Background

Postoperative chylothorax may be caused by iatrogenic injury of the collateral lymphatic ducts after thoracic surgery. Although traditional treatment could be considered in most cases, resolution may be slow. Radiological interventions have recently been developed to manage postoperative chylothorax. This study aimed to compare radiological interventions and conservative management in patients with postoperative chylothorax.

Methods

We retrospectively reviewed periprocedural drainage time, length of hospital stay, and nil per os (NPO) duration in 7 patients who received radiological interventions (intervention group [IG]) and in 9 patients who received conservative management (non-intervention group [NG]).

Results

The baseline characteristics of the patients in the IG and NG were comparable; however, the median drainage time and median length of hospital stay after detection of chylothorax were significantly shorter in the IG than in the NG (6 vs. 10 days, p=0.036 and 10 vs. 20 days, p=0.025, respectively). NPO duration after chylothorax detection and total drainage duration were somewhat shorter in the IG than in the NG (5 vs. 7 days and 8 vs. 14 days, respectively).

Conclusion

This study showed that radiological interventions reduced the duration of drainage and the length of hospital stay, allowing an earlier return to normal life. To overcome several limitations of this study, a prospective, randomized controlled trial with a larger number of patients is recommended.