Indocyanine green fluorescence imaging technology for the treatment of chylothorax after oesophageal cancer: A case report.

Chylothorax is a serious postoperative complication of oesophageal cancer, and to date, there is no standardized and effective intraoperative diagnostic tool that can be used to identify the thoracic duct and determine the location of lymphatic fistulas. A 50-year-old patient with oesophageal squamous cell carcinoma developed chylothorax after thoracolaparoscopy combined with radical resection of oesophageal cancer. Twelve hours after surgery, 1200 mL of clear fluid was drained from the thoracic drainage tube, and a chyle test was sent. A thoracothoracic duct ligation procedure was performed on the first day after surgery. Although fluid accumulating in the posterior mediastinum was observed, the location of the lymphatic fistula could not be determined. During the surgery, indocyanine green (ICG) was injected into the bilateral inguinal lymph nodes, and a fluorescent lens was used to determine the location of the lymphatic fistula so the surgeon could ligate the thoracic duct. ICG fluorescence imaging technology can help surgeons effectively manage chylothorax after oesophageal cancer surgery. To our knowledge, this is the first report to describe the use of ICG fluorescence imaging technology to treat postoperative chylothorax in patients with oesophageal cancer in China.

Thoracic Duct Visualization in Esophageal Resection: A Pilot Trial.

INTRODUCTION: Inadvertent thoracic duct injury is common during esophagectomy and may result in postoperative chylothorax. This study's objective was to investigate utility of patent blue injection as a modality for intraoperative thoracic duct visualization. METHODS: A prospective, single-arm, interventional study of patients undergoing minimally invasive esophagectomy was performed. Patients were injected with patent blue dye into both groins prior to thoracic stage of surgery and assessed for duct visualization. Control group was formed by propensity score matching using retrospectively collected data regarding patients who underwent esophagectomy. RESULTS: A total of 25 patients were included in analysis, compared to a control of 50 patients after matching. Thoracic duct was visualized in 60% of patients in the study group (15/25 patients). Significant differences were found between study and control groups (p < 0.05) with regards to median operative time (422 vs. 285 min, respectively), overall complications (16 vs. 34%, respectively), and median postoperative length of stay (13.5 vs. 10 days, respectively). There was a difference in rate of chyle leak between study and control groups; however, this was not significant (0 vs. 12%, respectively, p = 0.17). CONCLUSION: Patent blue injection represents a simple method for thoracic duct visualization during minimally invasive esophagectomy which may improve surgical outcomes.

Thoracic duct identification with indocyanine green fluorescence to prevent chyle leaks during minimally invasive esophagectomy.

INTRODUCTION: Chylothorax (CT) is a rare yet serious complication after esophagectomy. Identification of the thoracic duct (TD) during esophagectomy is challenging due to its anatomical variation. Real-time identification of TD may help to prevent its injury. Near infra-red imaging with Indocyanine green (ICG) is a novel technique that recently has been used to overcome this issue. METHODS: Patients who underwent minimally invasive esophagectomy for esophageal cancer were divided into two groups with and without ICG. We injected ICG into bilateral superficial inguinal lymph nodes. Identification of TD and its injuries during the operation was evaluated and compared with the non-ICG group. RESULTS: Eighteen patients received ICG, and 18 patients underwent surgery without ICG. Each group had one (5.5%) TD ligation. In the ICG group injury was detected intraoperative, and ligation was done at the site of injury. In all cases, the entire thoracic course of TD was visualized intraoperatively after a mean time of 81.39 min from ICG injection to visualization. The Mean extra time for ICG injection was 11.94 min. In the ICG group, no patient suffered from CT. One patient in the non-ICG group developed CT after surgery that was managed conservatively. According to Fisher's exact test, there was no significant association between CT development and ICG use, possibly due to the small sample size. CONCLUSIONS: This study confirms that ICG administration into bilateral superficial inguinal lymph nodes can highlight the TD and reduce its damage during esophagectomy. It can be a standard method for the prevention of postoperative CT.

Treatment Of Post-Operative Chylothorax: The Role Of Intranodal Lymphangiography And Thoracic Duct Disruption.

Thoracic duct embolization has been increasingly adopted as a first-line therapy of chylothorax and this procedure includes lipiodol lymphangiography, thoracic duct access and embolization. Lymphangiography itself has a therapeutic role, with volume-dependent success rates of 37%-97% and even a reported 100% success rate in outputs of < 500 mL/day. We present a clinical case of a 48-years-old man diagnosed with esophageal squamous cell carcinoma, who underwent esophagectomy and presented with post-operative high-output (> 1L/day) chylothorax; thoracic duct embolization was proposed. Even though thoracic duct access and embolization were not achieved due to technical and anatomical factors, lipiodol lymphangiography and possibly thoracic duct maceration (after several punctures/attempts) contributed to the clinical success of the procedure, and this chylothorax with output values superior to those reported in the literature resolved within three days. As such, the therapeutic role of intranodal lymphangiography and thoracic duct disruption should be taken into account.

Thoracic Duct Embolization for Treatment of Chyle Leakage After Thyroidectomy and Neck Dissection.

OBJECTIVE: This study aimed to evaluate the safety and efficacy of intranodal lymphangiography and thoracic duct embolization (TDE) for chyle leakage (CL) after thyroid surgery. MATERIALS AND METHODS: Fourteen patients who underwent intranodal lymphangiography and TDE for CL after thyroid surgery were included in this retrospective study. Among the 14 patients, 13 underwent bilateral total thyroidectomy with neck dissection (central compartment neck dissection [CCND], n = 13; left modified radical neck dissection (MRND), n = 11; bilateral MRND, n = 2), and one patient underwent left hemithyroidectomy with CCND. Ten patients (76.9%) had high-output CL (> 500 mL/d). Before the procedure, surgical intervention was attempted in three patients (thoracic duct ligation, n = 1; lymphatic leakage site ligation, n = 2). Lymphangiographic findings, technical and clinical successes, and complications were analyzed. Technical success was defined as the successful embolization of the thoracic duct after access to the lymphatic duct via the transabdominal route. Clinical success was defined as the resolution of CL or surgical drain removal. RESULTS: On lymphangiography, ethiodized oil leakage near the surgical bed was identified in 12 of 14 patients (85.7%). The technical success rate of TDE was 78.6% (11/14). Transabdominal antegrade access was not feasible due to the inability to visualize the identifiable cisterna chyli or a prominent lumbar lymphatic duct. Among patients who underwent a technically successful TDE, the clinical success rate was 90.1% (10/11). The median time from the procedure to drain removal was 3 days (with a range of 1-13 days) for the 13 patients who underwent surgical drainage. No CL recurrence was observed during the follow-up period (ranging from 2-44 months; median, 8 months). There were no complications, except for one case of chylothorax that developed after TDE. CONCLUSION: TDE appears to be a safe and effective minimally invasive treatment option for CL after thyroid surgery, with acceptable technical and clinical success rates.

Thoracic Duct Occlusion Leading to Intermittent Left Supraclavicular Swelling and Pancreatitis.

Intermittent left supraclavicular swelling is an uncommon and elusive condition that can lead to extensive diagnostic workups to determine the etiology and treatment. One potential cause is partial, intermittent, or complete thoracic duct occlusion (TDO). We report on a patient who presented with chronic, intermittent left supraclavicular swelling and abdominal pain that was relieved by thoracic duct angioplasty. Thoracic duct occlusion should be included in the differential diagnosis of left supraclavicular swelling. Lymphatic imaging can facilitate the diagnosis and allows for potential percutaneous treatment. Laryngoscope, 134:1313-1315, 2024.

Coil or Plug-Assisted Ethylene Vinyl Alcohol Copolymer (EVOH) Thoracic Duct Embolization in the Treatment of Postoperative Chylothorax.

Eleven patients (5 men, 6 women) with post-operative thoracic duct injuries and high output chylothorax were treated with thoracic duct embolization (TDE). Six patients underwent intraprocedural thoracic duct ligation at the time of original procedure. In all cases, the pleural fluid demonstrated high triglyceride levels (414 mg/dL; interquartile range [IQR], 345 mg/dL). Median daily (IQR) chest tube outputs before and after TDE were 900 mL (1,200 mL) and 325 mL (630 mL), respectively. Coil- or plug-assisted ethylene vinyl alcohol (EVOH) copolymer was used as embolic agent in all patients. Technical and clinical success rates were 100% and 82%, respectively. Nontarget venous embolization of EVOH copolymer was not identified on subsequent imaging.

Efficacy and safety of near-infrared fluorescence identification of the thoracic duct during left lateral neck dissection.

BACKGROUND: Thoracic duct leaks occur in up to 5% of left lateral neck dissections. No one imaging modality is routinely used to identify the thoracic duct intraoperatively. The goal of our study was to evaluate the efficacy and safety of indocyanine green lymphangiography for intraoperative identification of the thoracic duct compared to traditional methods using ambient and evaluate the optimal timing of indocyanine green administration. METHODS: We enrolled all patients who underwent left lateral neck dissection at our institution from 2018 to 2022 in this prospective clinical trial. After indocyanine green injection into the dorsum of the foot, we performed intraoperative imaging was performed with a near-infrared fluorescence camera. We reported the data using descriptive statistics. RESULTS: Of the 42 patients we enrolled, 14 had prior neck surgery, and 3 had prior external beam radiation. We visualized the thoracic duct with ambient light in 48% of patients and with near-infrared fluorescence visualization in 64%. In 17% of patients, we could identify the thoracic duct only using near-infrared fluorescence visualization, which occurred within 3 minutes of injection, and were required to re-dose 5 patients. We visualized the thoracic duct with near-infrared fluorescence in all patients with prior neck radiation and 77% of patients with prior neck surgery. One adverse reaction occurred (hypotension), and 5 intraoperative thoracic duct injuries occurred that were ligated. There with no chylous fistulas postoperatively. CONCLUSION: This trial demonstrates that near-infrared fluorescence identification of the thoracic duct is feasible and safe with indocyanine green lymphangiography, even in patients with prior neck surgery or radiation.

Impact of fluorescent thoracic duct lymphography via intranodal approach in minimal access esophageal cancer surgery.

PURPOSE: Chyle leak resulting from thoracic duct (TD) injury poses significant morbidity and mortality challenges. We assessed the feasibility of using near-infrared (NIR) indocyanine green (ICG) imaging for intraoperative fluorescence TD lymphography during minimal access esophagectomy (MAE) in a semiprone position with inguinal nodal injection of ICG dye. METHODS: Ninety-nine patients with esophageal or gastroesophageal junctional cancer undergoing MAE received inguinal node injections of 2.5 mg ICG dye (total 5 mg) under sonographic guidance during anesthesia induction. Stryker's 1688 AIM HD system was used in 76 cases, Karl Storz OPAL 1 S in 20, and in three cases the Karl Storz Rubina. RESULTS: In 93 patients (94%), the TD was clearly delineated along its entire length; it was not visualized in 6 patients (6%). Fluorescence guidance facilitated TD ligation in 16 cases, while 3 cases required clipping of duct tributaries for oncological considerations. Twenty-eight patients exhibited minor duct variations. Fluorescence was sustained throughout surgery (median observation time 60 min post-injection; range 30-330). No patient experienced any chyle leak within 30 days post-surgery and no adverse reactions to ICG was evident. CONCLUSIONS: Intraoperative fluorescence TD lymphography using ICG during MAE in a semiprone position with inguinal nodal injection proved safe, feasible, and effective, allowing clear visualization of the TD in almost all cases. This approach aids safe ligation and reduces chyle leak risk. It offers real-time imaging of TD anatomy and variations, providing valuable feedback to surgeons for managing TD injuries during MAE procedures and represents an excellent educational tool.

Simultaneous Visualization of the Thoracic Duct and Blood Vessels Using MRI: A Comparison Between Balanced Turbo-field-echo and Spin-echo.

OBJECTIVE: Magnetic resonance thoracic ductography (MRTD), concomitant with blood vessel imaging, provides useful anatomical information. The purpose of this study was to assess the visibility of the thoracic duct and blood vessels simultaneously by MRTD using balanced turbo-field-echo (bTFE) and turbo spin-echo (TSE). METHODS: MRTDs concomitant with blood vessel imaging on bTFE and TSE were obtained for 10 healthy volunteers with a 1.5T-magnetic resonance unit. Visibility of the thoracic duct, blood vessels in the thoracic region; motion artifacts; and overall image quality were scored by two radiologists using three-to-five-point scales; those were compared between bTFE and TSE. RESULTS: The thoracic duct was generally well-visualized on MRTD sequences. The upper part of the thoracic duct was better visualized on TSE than on bTFE (p < 0.05). The blood vessels were well visualized on bTFE and TSE; the bilateral subclavian arteries and the right subclavian veins were better visualized on TSE than on bTFE (all p < 0.05). Motion artifacts and overall image quality were better on TSE than on bTFE (p = 0.0039 and 0.0020, respectively). CONCLUSION: MRTD concomitant with blood vessel imaging on TSE has better visibility of the thoracic duct and blood vessels than bTFE.

Magnetic resonance three-dimensional steady-state free precession imaging of the thoracic duct in patients with Fontan circulation and its relationship to outcomes.

BACKGROUND: Lymphatic complications are common in patients with Fontan circulation. Three-dimensional balanced steady-state free precession (3D bSSFP) angiography by cardiovascular magnetic resonance (CMR) is widely used for cardiovascular anatomical assessment. We sought to determine the frequency of thoracic duct (TD) visualization using 3D bSSFP images and assess whether TD characteristics are associated with clinical outcomes. METHODS: This was a retrospective, single-center study of patients with Fontan circulation who underwent CMR. Frequency matching of age at CMR was used to construct a comparison group of patients with repaired tetralogy of Fallot (rTOF). TD characteristics included maximum diameter and a qualitative assessment of tortuosity. Clinical outcomes included protein-losing enteropathy (PLE), plastic bronchitis, listing for heart transplantation, and death. A composite outcome was defined as presence of any of these events. RESULTS: The study included 189 Fontan patients (median age 16.1 years, IQR 11.0-23.2 years) and 36 rTOF patients (median age 15.7 years, IQR 11.1-23.7 years). The TD diameter was larger (median 2.50 vs. 1.95 mm, p = 0.002) and more often well visualized (65% vs. 22%, p < 0.001) in Fontan patients vs. rTOF patients. TD dimension increased mildly with age in Fontan patients, R = 0.19, p = 0.01. In Fontan patients, the TD diameter was larger in those with PLE vs. without PLE (age-adjusted mean 4.11 vs. 2.72, p = 0.005), and was more tortuous in those with NYHA class ≥ II vs. class I (moderate or greater tortuosity 75% vs. 28.5%, p = 0.02). Larger TD diameter was associated with a lower ventricular ejection fraction that was independent of age (partial correlation = - 0.22, p = 0.02). More tortuous TDs had a higher end-systolic volume (mean 70.0 mL/m2 vs. 57.3 mL/m2, p = 0.03), lower creatinine (mean 0.61 mg/dL vs. 0.70 mg/dL, p = 0.04), and a higher absolute lymphocyte count (mean 1.80 K cells/µL vs. 0.76 K cells/µL, p = 0.003). The composite outcome was present in 6% of Fontan patients and was not associated with TD diameter (p = 0.50) or tortuosity (p = 0.09). CONCLUSIONS: The TD is well visualized in two-thirds of patients with Fontan circulation on 3D-bSSFP images. Larger TD diameter is associated with PLE and increased TD tortuosity is associated with an NYHA class ≥ II.

Therapeutic effect of lymphography in the postoperative chylothorax - case reports and literature review.

Postoperative chylothorax is a well-known rare complication of thoracic surgery. It is a serious complication that is fatal in cases of inadequate treatment. The authors present 2 cases of postoperative chylothorax that were successfully treated by performing pedal and/or intranodal lymphography. In one case, the patient underwent lymphography after previous unsuccessful surgical ligation of the thoracic duct. The presented case reports describe therapeutic importance of conventional lymphography as a minimally invasive treatment of the postoperative chylothorax.

Feasibility study of percutaneous thoracic duct embolization with lower-limb intermittent pneumatic compression devices

PURPOSE: To demonstrate intranodal thoracic duct embolization (TDE) for treating chyle leaks following thoracic surgery and the feasibility of applying lower-limb intermittent pneumatic compression devices during TDE. METHODS: Between December 2017 and October 2020, 12 consecutive TDEs for post-operative chyle leaks were performed in 11 patients using intranodal lymphangiogram (IL) with an intermittent pneumatic compressive device applied to the lower limb. The procedure's duration, technical/clinical success, and complications were retrospectively evaluated. RESULTS: IL was successful at imaging the thoracic duct in all procedures (100%), and TDE had an intention- to-treat success rate of 92% (11/12). No related complications were observed during follow-up, which took place at a mean of 27 days. The time from the commencement of lymphangiogram until visualization of the thoracic duct was a mean of 21.6 min, and the mean overall procedure time was 87.3 min. CONCLUSION: This study supports IL-guided TDE as a safe and effective option to treat post-thoracic surgery chyle leaks. We revealed shorter lymphangiogram times compared with previously published studies, and we postulate that the application of intermittent lower-limb pneumatic compressive devices contributed toward this study's results by expediting the return of lymph from the lower limb. This study is the first to illustrate this approach in TDE and advocates for randomized controlled studies to further evaluate the influence of intermittent pneumatic compressive devices on the procedure.

Near-infrared fluorescence imaging of thoracic duct in minimally invasive esophagectomy.

Chylothorax is a serious complication after esophagectomy and there are unmet needs for new intraoperative navigation tools to reduce its incidence. The aim of this study is to explore the feasibility and effectiveness of near-infrared fluorescence imaging (NIR-FI) with indocyanine green (ICG) to identify thoracic ducts (TDs) and chyle leakage during video-assisted thoracoscopic esophagectomy. We recruited 41 patients who underwent thoraco-laparoscopic minimally invasive esophagectomy (MIE) for esophageal cancer in this prospective, open-label, single-arm clinical trial. ICG was injected into the right inguinal region before operations, after which TD anatomy and potential chyle leakage were checked under the near-infrared fluorescence intraoperatively. In 38 of 41 patients (92.7%) using NIR-FI, TDs were visible in high contrast. The mean signal-to-background ratio (SBR) value of all fluorescent TDs was 3.05 ± 1.56. Fluorescence imaging of TDs could be detected 0.5 hours after ICG injection and last up to 3 hours with an acceptable SBR value. The optimal observation time window is from about 1 to 2 hours after ICG injection. Under the guidance of real-time NIR-FI, three patients were found to have chylous leakage and the selective TD ligations were performed intraoperatively. No patient had postoperative chylothorax. NIR-FI with ICG can provide highly sensitive and real-time assessment of TDs as well as determine the source of chyle leakage, which might help reduce TD injury and direct selective TD ligation. It could be a promising navigation tool to reduce the incidence of chylothorax after minimally invasive esophagectomy.

The cisterna chyli: a systematic review of definition, prevalence, and anatomy.

The cisterna chyli is a lymphatic structure found at the caudal end of the thoracic duct that receives lymph draining from the abdominal and pelvic viscera and lower limbs. In addition to being an important landmark in retroperitoneal surgery, it is the key gateway for interventional radiology procedures targeting the thoracic duct. A detailed understanding of its anatomy is required to facilitate more accurate intervention, but an exhaustive summary is lacking. A systematic review was conducted, and 49 published human studies met the inclusion criteria. Studies included both healthy volunteers and patients and were not restricted by language or date. The detectability of the cisterna chyli is highly variable, ranging from 1.7 to 98%, depending on the study method and criteria used. Its anatomy is variable in terms of location (vertebral level of T10 to L3), size (ranging 2-32 mm in maximum diameter and 13-80 mm in maximum length), morphology, and tributaries. The size of the cisterna chyli increases in some disease states, though its utility as a marker of disease is uncertain. The anatomy of the cisterna chyli is highly variable, and it appears to increase in size in some disease states. The lack of well-defined criteria for the structure and the wide variation in reported detection rates prevent accurate estimation of its natural prevalence in humans.

Cervical thoracic duct cyst: a conservative resolution.

A woman in her 70s presented with an enlarging, asymptomatic palpable mass in the left supraclavicular fossa. The clinical impression was of a lipoma. Imaging showed a cystic lesion with continuity of a tubular structure leading to the carotid sheath. Cytology was consistent with thoracic duct sampling. A diagnosis of the rare entity of a thoracic duct cyst with supraclavicular extension was made. This was managed conservatively via repeated aspirations which reduced the size of the mass.

Imaging Findings of Thoracic Lymphatic Abnormalities.

The lymphatic system plays an important role in balancing fluid compartments in the body. It is disrupted by various disease processes in the thorax, including injury to the thoracic lymphatic duct after surgery, as well as malignancy and heart failure. Because of the small size of lymphatic vessels, imaging of the lymphatics is relatively difficult, and effective imaging methods are still being optimized and developed. The standard of reference for lymphatic imaging has been conventional lymphangiography for several decades. Other modalities such as CT, noncontrast or contrast-enhanced MRI, and lymphoscintigraphy can also demonstrate lymphatic abnormalities and help in treatment planning. Imaging findings associated with lymphatic abnormalities can be seen in the pulmonary parenchyma, pleural space, and mediastinum. In the pulmonary parenchyma, common findings include interlobular septal thickening as well as reversal of lymphatic flow with intravasation of contrast material into pulmonary lymphatics. In the pleural space, findings include chylous pleural effusion and occasionally nonchylous pleural effusion. In the mediastinum, thoracic duct leak, plexiform thoracic duct, lymphatic malformations, and lymphangiectasis may occur. Management of chylothorax includes conservative or medical treatment, surgery, and interventional radiology procedures. The authors discuss thoracic lymphatic anatomy, imaging manifestations of lymphatic abnormalities in the various anatomic compartments, and interventional radiology treatment of chylothorax. Radiologists should be familiar with these imaging findings for diagnosis and to help guide appropriate management. ©RSNA, 2022.