Lymphography: An Old Technique Retains Its Usefulness

Refractory chylothorax following COVID-19: Successful surgical management of a rare complication; a case report

INTRODUCTION AND IMPORTANCE

Chylothorax is an uncommon complication linked to COVID-19. The fundamental pathophysiology and most effective management strategy are still uncertain.

CASE PRESENTATION

A 72-year-old man presented with worsening dyspnea and fatigue one month post-COVID-19. Imaging demonstrated a significant right pleural effusion, with thoracentesis confirming the presence of chylothorax. Despite the implementation of conservative interventions, the effusion remained unresolved. During the right thoracotomy procedure, a 1 cm (about 0.39 in) perforation in proximity to the Azygos vein, encircled by hypertrophic lymph nodes, was identified. Surgical intervention successfully alleviated the symptoms.

CLINICAL DISCUSSION

This case implies that mediastinal lymphadenopathy because of COVID-19 could potentially obstruct and interfere with the thoracic duct. This emphasizes the significance of considering chylothorax as a crucial diagnostic possibility in individuals presenting with new onset pleural effusions following COVID-19. Although conservative approaches are typically the first line of management, persistent cases may necessitate surgical intervention to target the root cause.

CONCLUSIONS

Additional research is imperative to elucidate the intricate pathways connecting COVID-19 and chylothorax, as well as to ascertain the most effective diagnostic and therapeutic approaches.

Current diagnostic and quantitative techniques in the field of lymphedema management: a critical review

Lymphedema evaluation entails multifaceted considerations for which options continue to evolve and emerge. This paper provides a critical review of the current status of diagnostic and quantitative measures for lymphedema, from traditional and novel bedside assessment tools for volumetric and fluid assessment, to advanced imaging modalities. Modalities are contrasted with regard to empirical support and feasibility of clinical implementation. The manuscript proposes a grid framework for comparing the ability of each modality to quantify specific lymphedema characteristics, including distribution, dysmorphism, tissue composition and fluid content, lymphatic anatomy and function, metaplasia, clinical symptoms, and quality of life and function. This review additionally applies a similar framework approach to consider how well assessment tools support important clinical needs, including: (1) screening, (2) diagnosis and differential diagnosis, (3) individualization of treatment, and (4) monitoring treatment response. The framework highlights which clinical needs are served by an abundance of assessment tools and identifies others that have problematically few. The framework clarifies which tools have greater or lesser empirical support. The framework is designed to assist stakeholders in selecting appropriate diagnostic and surveillance modalities, gauging levels of confidence when applying tools to specific clinical needs, elucidating overarching patterns of diagnostic and quantitative strengths and weaknesses, and informing future investigation.

Interventional solutions for post-surgical problems: a lymphatic leaks review

The lymphatic circulation plays a crucial role in maintaining fluid balance and supporting immune responses by returning serum proteins and lipids to the systemic circulation. Lymphatic leaks, though rare, pose significant challenges post-radical neck surgery, oesophagectomy, and thoracic or retroperitoneal oncological resections, leading to heightened morbidity and mortality. Managing lymphatic leaks necessitates consideration of aetiology, severity, and volume of leakage. Traditionally, treatment involved conservative measures such as dietary restrictions, drainage, and medical management, with surgical intervention reserved for severe cases, albeit with variable outcomes and extended recovery periods. Lymphography, introduced in the 1950s, initially served as a diagnostic tool for lymphoedema, lymphoma, tumour staging, and monitoring chemotherapy response. However, its widespread adoption was impeded by alternative techniques like Computed Tomography, learning curves, and its associated complications. Contemporary lymphatic interventions have evolved, favouring nodal lymphangiography over pedal lymphangiography for its technical simplicity and reduced complexity. Effective management of chylous leaks mandates a multimodal approach encompassing clinical evaluation and imaging techniques. In cases where conservative management proves ineffective, embolization through conventional lymphangiography by bipedal dissection or intranodal injection emerges as a viable option. This review underscores the importance of a comprehensive approach to diagnosing and treating lymphatic leaks, highlighting advancements in imaging and therapeutic interventions that enhance patient outcomes.

Lymphoscintigraphy Findings are Associated with Outcome in Children with Chylothorax After Cardiac Surgery

Postoperative chylothorax in patients with congenital heart diseases (CHD) results in poor outcomes if anatomical and functional abnormalities of the lymphatic system are present. While these abnormalities are typically diagnosed by intranodal lymphangiography and dynamic contrast magnetic resonance lymphangiography, the usefulness of lymphoscintigraphy in these patients has not been evaluated. Between January 2019 and December 2021, 28 lymphoscintigraphies were performed in our institution for investigating prolonged pleural effusion after cardiac surgery. The images were assessed by three board-certified pediatric cardiologists retrospectively to determine the likelihood of a central lymphatic flow disorder. The likelihood was scored (range 1-3) based on structural abnormalities and congestive flow in the lymphatic system. Those scores were summed and the likelihood was categorized as low to intermediate (< 8 points) or high (8 or 9 points). Median age at lymphoscintigraphy was 129 days (IQR, 41-412 days), it was performed at a median of 22 days (IQR, 17-43) after surgery, and median score was 6 points (IQR, 4-7.5). Kendall's coefficient of concordance (0.867; p < 0.05) indicated high inter-rater reliability. Overall survival at 6 months after surgery was 92.5% in the low-to-intermediate group but 68.6% in the high group (p < 0.05), and duration of postoperative thoracic drainage was 27 and 58 days, respectively (p < 0.05). Lymphatic abnormalities detected by lymphoscintigraphy were associated with poorer outcomes. Lymphoscintigraphy was thought to be useful in assessing anatomic and functional lymphatic abnormalities, despite its minimal invasiveness.

Lymphatic drainage dysfunction via narrowing of the lumen of cisterna chyli and thoracic duct after luminal dilation

BACKGROUND

The chronological pattern of extrahepatic lymphatic vessel progression in the course of chronic liver disease has not been clarified. This study aimed to clarify the chronological changes in lymphatic vessels with liver disease progression.

METHODS

This was a prospective cross-sectional study that enrolled a total of 199 patients. The maximum diameter of the cisterna chyli (CC) or terminal thoracic duct (tTD) was measured using computed tomography or ultrasonography, respectively. Changes in the maximum diameters of the CC and tTD were evaluated with patients with chronic liver disease as the pilot set (n = 138). Subsequently, we examined whether CC/tTD could be used to re-allocate unclassified patients by the Baveno-VII criteria to appropriately diagnose clinically significant portal hypertension (CSPH) in the pilot and validation sets.

RESULTS

In the pilot set, a scatter-plot showed that both CC and tTD were narrowed as terminal features in chronic liver disease after dilation. Because there was a significant correlation between the CC diameter and hepatic venous pressure gradient (r = 0.724) in unclassified patients, the diagnostic value of CC and tTD for CSPH was good (AUC: 0.961 and 0.913, respectively). After re-allocation, 68 and 27 unclassified patients were reduced to 4 and 5 in the pilot and validation sets, respectively.

CONCLUSION

Both the CC and tTD narrow in the course of liver disease after dilation. Moreover, the maximum diameter of the CC and tTD can be used to re-allocate patients who are unclassified according to the Baveno-VII criteria.

CLINICAL TRIAL NUMBER

UMIN trial no. 000044857.

Therapeutic lymphangiography with ethiodized oil for the management of lymphoceles and chylous ascites

PURPOSE

The purpose of this study was to analyze the safety, technical success and clinical outcome of percutaneous intranodal ethiodized oil (Lipiodol®) based lymphangiography (L-LAG) for the management of refractory pelvic lymphoceles or chylous ascites using high doses of ethiodized oil.

MATERIALS AND METHODS

Thirty-four patients presenting with symptomatic, refractory postoperative pelvic lymphocele or chylous ascites referred for theranostic, inguinal, intranodal L-LAG treatment between May 2018 and November 2021 were retrospectively included. There were 21 men and 13 women, with a mean age of 62.7 ± 16.2 (standard deviation) years (age range: 9-86 years), who underwent a total of 49 L-LAG for the management of lymphoceles (n = 14), chylous ascites (n = 18) or a combination of lymphocele and chylous ascites (n = 2). Clinical and radiological pre-interventional, procedural and follow-up data up to January 2022 were collected from patients' electronic medical records and imaging files.

RESULTS

Technical success was obtained in 48 out of 49 L-LAG (98%). No complications related to L-LAG were noted. After one or more L-LAG, clinical success was obtained in 30 patients (88%) with a mean of 1.4 interventions per patient and mean intranodal injected volume of 29 mL of ethiodized oil per session. The remaining four patients (12%), with one or more failed L-LAG, underwent additional surgical intervention to definitively treat the postoperative lymphatic leakage.

CONCLUSION

L-LAG using high doses of ethiodized oil is a minimally invasive, safe and effective treatment of postoperative pelvic lymphocele or chylous ascites. Multiple sessions may be needed to obtain a meaningful clinical result.

Chyluria: non-enhanced MR lymphography

Chyluria is an uncommon medical condition resulting from an abnormal communication between the abdominal lymphatic system and the urinary tract, which results in the presence of chyle in the urine, making it appear milky white. Proper diagnosis is demonstrated by the concentration of urinary lipids. Worldwide, chyluria is most commonly associated with the parasite Wuchereria bancrofti. However, in Europe and North America, where the condition is rare, non-parasitic etiologies predominate. Identifying the cause and location of the uro-lymphatic communication is essential in guiding therapeutic management, but imaging the lymphatic channels remains a challenge. Magnetic resonance (MR) lymphography, a non-invasive free-breathing 3D high-resolution fast-recovery fast spin-echo sequence similar to that used for 3D MR cholangiopancreatography, may demonstrate the cause and location of an abnormal communication between the lymphatic system and urinary tract. In parasitic causes of chyluria, dilated lymphatics vessels communicating with the lymphatic system are demonstrated. In non-parasitic causes of chyluria channel type lymphatic malformations are the most common. Markedly dilated and dysplastic lymphatic vessels communicating with the urinary tract are demonstrated. In addition, other cystic or channel type lymphatic malformations such as thoracic, soft tissue or bone abnormalities may be observed. This review describes the abdominal lymphatic diseases leading to chyluria and presents the technique and images obtained with non-enhanced MR lymphography to enable radiologists in identifying and classifying uro-lymphatic fistulae.Critical relevance statement: Non-enhanced MR lymphography enables the identification and categorization of uro-lymphatic fistulae.

MRI of Lymphedema

Lymphedema is a devastating disease that has no cure. Management of lymphedema has evolved rapidly over the past two decades with the advent of surgeries that can ameliorate symptoms. MRI has played an increasingly important role in the diagnosis and evaluation of lymphedema, as it provides high spatial resolution of the distribution and severity of soft tissue edema, characterizes diseased lymphatic channels, and assesses secondary effects such as fat hypertrophy. Many different MR techniques have been developed for the evaluation of lymphedema, and the modality can be tailored to suit the needs of a lymphatic clinic. In this review article we provide an overview of lymphedema, current management options, and the current role of MRI in lymphedema diagnosis and management. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 5.

Correlation between capsule endoscopy classification and CT lymphangiography of primary intestinal lymphangiectasia

AIM

To investigate the correlation between capsule endoscopy (CE) classification of primary intestinal lymphangiectasia (PIL) and computed tomography (CT) lymphangiography (CTL).

MATERIALS AND METHODS

A total of 52 patients with diagnosed PIL were enrolled. All patients were examined using CTL and small intestinal CE before surgery. CE assessments included the morphology, scope, colour, and size of lesions. CTL assessments included intestinal wall, lymphatic vessel dilatation, lymph fluid reflux, and lymphatic fistula. Patients were divided into three groups according to type diagnosed by CE, and the CTL characteristics were analysed among the groups.

RESULTS

CE showed 15 patients with type I, 27 with II, and 10 with type III. Intestinal wall thickening was observed in 15 type I, 21 type II, and seven type III. Pericardial effusion was observed in only three type I patients; the difference among types was statistically significant (p=0.02). Abnormal contrast agent distribution in the intestinal wall and mesentery was observed in 15 type II patients, and the difference was significantly greater than that of types I and III (p=0.02). Abnormal contrast agent distribution in the abdominal cavity was observed in 12 type II, and the difference was statistically significant (p=0.03).

CONCLUSION

The CE PIL classification reflects the extent and scope of intestinal mucosa lesions; CTL more systematically demonstrates abnormal lymphatic vessels or reflux, and its manifestations of PIL are related to the CE classification. The combination of CTL with CE is useful for accurately evaluating PIL, and provides guidance for preoperative assessment and treatment management of PIL patients.

Emerging Indications for Interventional Oncology: Expert Discussion on New Locoregional Treatments

Interventional oncology (IO) employs image-guided techniques to perform minimally invasive procedures, providing lower-risk alternatives to many traditional medical and surgical therapies for cancer patients. Since its advent, due to rapidly evolving research development, its role has expanded to encompass the diagnosis and treatment of diseases across multiple body systems. In detail, interventional oncology is expanding its role across a wide spectrum of disease sites, offering a potential cure, control, or palliative care for many types of cancer patients. Due to its widespread use, a comprehensive review of the new indications for locoregional procedures is mandatory. This article summarizes the expert discussion and report from the "MIOLive Meet SIO" (Society of Interventional Oncology) session during the last MIOLive 2022 (Mediterranean Interventional Oncology Live) congress held in Rome, Italy, integrating evidence-reported literature and experience-based perceptions. The aim of this paper is to provide an updated review of the new techniques and devices available for innovative indications not only to residents and fellows but also to colleagues approaching locoregional treatments.

Recent advancement of imaging strategies of the lymphatic system: Answer to the decades old questions

The role of the lymphatic system in maintaining tissue homeostasis and a number of different pathophysiological conditions has been well established. The complex and delicate structure of the lymphatics along with the limitations of conventional imaging techniques make lymphatic imaging particularly difficult. Thus, in-depth high-resolution imaging of lymphatic system is key to understanding the progression of lymphatic diseases and cancer metastases and would greatly benefit clinical decisions. In recent years, the advancement of imaging technologies and development of new tracers suitable for clinical applications has enabled imaging of the lymphatic system in both clinical and pre-clinical settings. In this current review, we have highlighted the advantages and disadvantages of different modern techniques such as near infra-red spectroscopy (NIRS), positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI) and fluorescence optical imaging, that has significantly impacted research in this field and has led to in-depth insights into progression of pathological states. This review also highlights the use of current imaging technologies, and tracers specific for immune cell markers to identify and track the immune cells in the lymphatic system that would help understand disease progression and remission in immune therapy regimen.

Intranodal lipiodol injection for the treatment of chyle leak in children - a preliminary experience

OBJECTIVE

To assess the effectiveness of intranodal lymphangiography using ethiodised oil (Lipiodol; Guerbet Japan, Tokyo, Japan) for the treatment of refractory cases of chylothorax and chylous ascites in the paediatric population.

METHODS

Between 2016 and 2020, eight children having chyle leak resistant to conservative management underwent intranodal lymphangiography using lipiodol injection. After ethical approval by the Institutional Review Board, these patients' data were retrospectively analysed. Technical success was defined by opacification of inguinal and retroperitoneal lymphatics while injection on fluoroscopy. Clinical success was defined as progressively decreasing drain output and eventual cessation of output within a week after the procedure. Long-term follow up was done as feasible.

RESULTS

Technical success was achieved in all the patients. Complete cessation of drain output was noted within 1 week of procedure in all patients indicating clinical success. One patient had recurrence of chylous leakage after an interval of 1 month and intranodal lymphangiography was repeated for that patient. The child had technical as well as clinical success after the repeat procedure. Hence a total of 9 procedures were performed in 8 patients.

CONCLUSION

Intranodal lymphangiography may prove to be a valuable minimally invasive therapeutic tool in cases of refractory chylous leakage in paediatric patients with minimal risk of complications.

ADVANCES IN KNOWLEDGE

Intranodal lymphangiography using lipiodol may prove to be a minimally invasive alternative in paediatric patients with refractory lymphatic leaks.

State-of-the-art imaging for lymphatic evaluation in children

The lymphatic system has been poorly understood and its importance neglected for decades. Growing understanding of lymphatic flow pathophysiology through peripheral and central lymphatic flow imaging has improved diagnosis and treatment options in children with lymphatic diseases. Flow dynamics can now be visualized by different means including dynamic contrast-enhanced magnetic resonance lymphangiography (DCMRL), the current standard technique to depict central lymphatics. Novel imaging modalities including intranodal, intrahepatic and intramesenteric DCMRL are quickly evolving and have shown important advances in the understanding and guidance of interventional procedures in children with intestinal lymphatic leaks. Lymphatic imaging is gaining importance in the radiologic and clinical fields and new techniques are emerging to overcome its limitations.

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.

Occurrence of pulmonary oil microembolism (POME) with intramuscular testosterone undecanoate injection: literature review

Testosterone undecanoate injections (TU), an oil-based depot, is a universal hormonal-based treatment which has been associated with pulmonary oil microembolism (POME). However, the rate of POME during routine intramuscular (IM) TU injection is unknown. Here, we conduct a peer-reviewed literature review investigating POME incidents in the setting of TU injections. A total of 48 articles were selected in the literature review, which included 29 studies that used TU and reported its effects. Relatively few POME cases were reported across multiple published studies, including those that focused particularly on the occurrence rate of POME while administrating IM TU. Of the 29 individual studies, which included 7 978 patients, eight studies reported a total of 88 incidence of POME cases or cough. This included episodes of cough that were not originally declared as POME. One post market review reported 223 cases per 3,107,652 injections. When POME did occur, almost all cases resolved spontaneously within 60 min without intervention. Overall, POME was observed to be rare.

Postmortem Retrograde Contrasted Infusion in Thoracic Duct Outflow: Imaging Effectiveness Analysis

Background

Thoracic duct (TD) anomaly can be quite variable and dangerous in surgical interventions in the neck region as there are numerous variations in its formation and topography. This highlights the importance of full knowledge about the TD and its anatomical variations. Thus, it is important to emphasize that the lack of anatomical-clinical knowledge or surgical skill during an intervention can significantly hamper successful results. The present study aimed to perform radiopaque contrast infusion into the TD of intact cadavers, either formalinized or refrigerated, to evaluate possible lymphatic architecture patterns via reverse lymphography.

Methodology

TD dissection was performed on 13 cadaveric specimens. After isolating the lymphatic vessel, it was cannulated with an nº 4 urethral probe fixed with cordonnet cotton. Then, a 10 mL syringe was attached to the urethral probe and the radiopaque iodinated contrast was injected into the TD under constant and gradual manual pressure.

Results

TD outflow was detected on the posterior surface of the junction between the internal jugular and the left subclavian veins, either as direct outflow (in 10 cases) or as an arc (in three cases). Reverse contrast progression was impossible in each of the attempts, probably due to valvular resistance and lumen obliteration, which completely prevented pressure infusion into the thoracic and abdominal parts of the TD.

Conclusions

We emphasize the impracticality of obtaining postmortem radiopaque images via retrograde contrast injection into the TD in formalinized or refrigerated bodies.

Retrograde transvenous selective lymphatic duct embolization in post donor nephrectomy chylous ascites

Chylous ascites is a rare, potentially sinister complication in post donor nephrectomy patients which may cause significant morbidity in form of severe malnutrition and an immuno-compromised state. We present two patients with post donor nephrectomy-related chylous leaks who failed conservative treatment. In both cases, lymphangiography was done first to detect the chylous leak site in the left renal fossa, and thereafter transvenous retrograde approach via left subclavian vein with selective lymphatic duct embolization of chylous leak was done with coils and glue successfully. Chylous ascites resolved in both patients after the embolization. Hence retrograde transvenous embolization technique appears to be an effective management option for refractory chylous leaks.

Current Clinical and Pre-Clinical Imaging Approaches to Study the Cancer-Associated Immune System

In the light of the success and the expected growth of its arsenal, immuno-therapy may become the standard neoadjuvant procedure for many cancers in the near future. However, aspects such as the identity, organization and the activation status of the peri- and intra-tumoral immune cells would represent important elements to weigh in the decision for the appropriate treatment. While important progress in non-invasive imaging of immune cells has been made over the last decades, it falls yet short of entering the clinics, let alone becoming a standard procedure. Here, we provide an overview of the different intra-vital imaging approaches in the clinics and in pre-clinical settings and discuss their benefits and drawbacks for assessing the activity of the immune system, globally and on a cellular level. Stimulated by further research, the future is likely to see many technological advances both on signal detection and emission as well as image specificity and resolution to tackle current hurdles. We anticipate that the ability to precisely determine an immune stage of cancer will capture the attention of the oncologist and will create a change in paradigm for cancer therapy.

Therapeutic Lymphangiography for Persistent Lymphatic Leak After Kidney Transplant: A Novel Technique

Lymphatic leakage is a common and well-described complication after kidney transplantation, occurring in up to 25% of patients. Accumulation of lymph is due to the surgical disruption of recipient lymphatic channels accompanying the external iliac vessels, complicated by lower extremity edema, wound breakdown, infection, and, if unresolved, graft loss due to extrinsic compression. In this report, we describe the novel use of diagnostic and therapeutic lymphangiography to successfully treat lymphatic leak after renal transplant that was resistant to drain placement, sclerotherapy, and laparoscopic peritoneal window creation. We also describe the methodology, indications, and contraindications and conclude that this technique is well-tolerated and offers a good option for complex lymph leaks that do not respond to conventional treatment. Further studies are required to compare its efficacy with other standard methods, including sclerotherapy and laparoscopic peritoneal fenestration, as the primary treatment modality.

Lymphangiography and Lymphatic Interventions

Compared with the traditional pedal lymphangiography, intranodal lymphangiography and MR lymphangiography have made imaging of the lymphatic system less challenging. Improvements in imaging and availability of newer catheters have allowed embolization of lymphatic system much more feasible that previously envisioned. In this article, we briefly review the anatomy, imaging, and current and future of lymphatic interventions.

SingHealth Radiology Archives pictorial essay Part 2: gastroenterology, musculoskeletal, and obstetrics and gynaecology cases

The Singapore Health Services cluster (SingHealth) radiology film archives are a valuable repository of local radiological cases dating back to the 1950s. Some of the cases in the archives are of historical medical interest, i.e. cerebral angiography in the workup of patients with hemiplegia. Other cases are of historical social interest, being conditions seen during earlier stages of Singapore's development, i.e. bound feet. The archives form a unique portal into the development of local radiology as well as the national development of Singapore. A selection from the archives is published in commemoration of the International Day of Radiology in 2020, as well as the 200th anniversary of the Singapore General Hospital in 2021. This pictorial essay comprises gastroenterology, musculoskeletal and obstetrics and gynaecology cases from the archives.

Chylothorax after Lung Cancer Surgery: A Key Factor Influencing Prognosis and Quality of Life

Chylothorax is caused by the accumulation of chylous fluid in the pleural cavity due to the injury of the thoracic duct or its tributaries. Chylothorax following lung cancer surgery, especially pulmonary resection and mediastinal lymph node dissection, is a raw potential postoperative complication as previously reported. Chylothorax might lead to a high mortality rate if not addressed in a timely fashion. This article reviews the anatomy of the thoracic duct, risk factors of postoperative chylothorax, diagnoses and management with chylothorax, and intraoperative prevention of chylothorax. With the development of researches on postoperative chylothorax, more effective treatment and prevention measures need to be proposed to better solve this clinical problem.

Isolated thoracic duct injury from blunt force trauma

Isolated thoracic duct injury is an uncommon clinical event and is rare in the setting of trauma. We describe a case of an isolated thoracic duct injury resulting in the development of bilateral chylothorax following a motor vehicle collision in the absence of any other definable injury. We outline the initial patient presentation and diagnosis. After failing a trial of conservative management the patient underwent lymphangiography followed by thoracic duct ligation with pleurodesis. This case highlights the importance of recognizing thoracic duct injury following trauma.

Chylous Ascites and Lymphoceles: Evaluation and Interventions

Kinmonth introduced lymphangiography in 1955 and it became an important tool in the diagnosis and treatment of malignant disease. The technique, based on bipedal approach, was difficult and time-consuming which limited its use in clinical practice. Cope is the father of percutaneous lymphatic interventions and he was the first person to access and intervene on the lymphatic system. After his initial work published on 1999, there has been an expansion of the lymphatic embolization techniques, particularly since the development of intranodal lymphangiography and advance lymphatic imaging. This article is focused on the evaluation and management of postoperative chylous ascites and lymphoceles. Their incidence is growing due to longer survival of cancer patients and more radical surgical approaches, leading to an increased morbidity and mortality in this patient population. Minimally invasive percutaneous lymphatic embolization is becoming a first-line therapy in patients with postoperative lymphatic leakage.

Lymphatic Imaging: Current Noninvasive and Invasive Techniques

After nearly disappearing, invasive lymphangiography not only has resurged, but new approaches have been developed to guide lymphatic interventions. At the same time, noninvasive lymphatic imaging is playing a larger role in the evaluation of lymphatic pathologies. Lymphangioscintigraphy, computed tomography lymphangiography, and magnetic resonance lymphangiography are increasingly being used as alternatives to invasive diagnostic lymphangiography. The purpose of this article is to review current invasive and noninvasive lymphatic imaging techniques.

Diagnosis of Lymphangiomatosis: A Study Based on CT Lymphangiography

RATIONALE AND OBJECTIVES

Lymphangiomatosis is a rare disease characterized by the widespread presence of lymphangiomas in any part of the body. In previous studies, lymphatic vessel abnormalities in lymphangiomatosis have only rarely been mentioned. The objective of this paper is to discuss the imaging features of lymphangiomatosis, including cystic lesions and lymphatic abnormalities, on computed tomography lymphangiography (CTL).

MATERIALS AND METHODS

All 34 patients who were diagnosed with lymphangiomatosis underwent direct lymphangiography followed by CTL. The CTL images were independently analyzed by two experienced radiologists. The CTL image analyses included assessment of the features of cystic lesions and lymphatic vessel abnormalities.

RESULTS

(i) CTL revealed several cystic lesions ranging in size from 3 mm to 14 cm; the lesions were located in the neck and shoulders (61.8%), mediastinum (52.9%), retroperitoneum (70.6%), and pelvis and perineum (64.7%). (ii) Approximately 29.4% of patients showed abnormal contrast medium accumulation in cystic masses. (iii) Approximately 67.6% of patients showed lymphatic reflux. (iv) Dilated lymphatic vessels were distributed in the mediastinum (38.2%), retroperitoneum (50.0%), pelvis and lower limbs (47.1%). (v) Finally, 8.8% of patients had perineal lymphatic fistulae, and 2.9% of patients had chyluria.

CONCLUSION

Lymphangiomatosis is a type of systemic lymphatic abnormality that is accompanied by multiple cystic lesions. The therapeutic measures for lymphangiomatosis are determined by the size of the cystic lesions. Furthermore, the prognosis of lymphangiomatosis is affected by lymphatic abnormalities.

Contemporary lymphatic interventions for post-operative lymphatic leaks

Post-operative lymphatic injuries are uncommon but increase morbidity and mortality in vulnerable patient populations. Post-surgical lymphatic leaks are most commonly a consequence of radical neck dissection, esophagectomy, and lung cancer resections or retroperitoneal surgeries such as radical nephrectomy and lymphadenectomy. Injury may occur anywhere along the lymphatic chains with most serious leaks occurring along the axial skeleton between the inguinal region and the left venous angle. The resultant clinical manifestations of a lymphatic leak are dependent on the location and severity of the lymphatic injury as well as patient factors. Treatment strategies are tailored toward the causative etiology, symptom severity, and daily leak volume with higher volume leaks warranting a more aggressive approach. Lymphangiography and lymphatic interventions, such as embolization, are increasingly applied for both the diagnosis and as a minimally invasive therapy for lymphatic injuries. Herein, a review of lymphatic anatomy, lymphangiography, and lymphatic interventions for the treatment of post-operative chylothorax, chylous ascites, and lymphocele is presented.

Complete resolution of chylopericardium after chemotherapy for chronic lymphocytic leukemia

Nontraumatic chylous pleural effusions (chylothorax) and pericardial effusions (chylopericardium) are rare. They can, however, accompany intrathoracic malignancies and, most commonly, lymphomas. An association of chronic lymphocytic leukemia (cll) with chylopericardium has rarely been reported. A 68-year-old woman with cll, previously treated with single-agent fludarabine in the community, developed pleuritic chest pain and a new pericardial effusion. Computed tomography (ct) imaging of her chest revealed a large pericardial effusion with progressive lymphadenopathy. Pericardiocentesis identified a chylous effusion, and complete evacuation was achieved by catheter drainage. The cll was not treated. An asymptomatic pericardial effusion subsequently recurred. Pericardiocentesis was not repeated. Lymph node biopsy and flow cytometry revealed no evidence of large-cell lymphoma transformation. The patient was treated with 6 cycles of chlorambucil and obinutuzumab. Imaging of her chest by ct between cycles 2 and 3 revealed a marked resolution of the intrathoracic lymphadenopathy, with complete disappearance of the pericardial effusion. Repeat imaging at 5 months and again at 3 years after completion of chemotherapy demonstrated no recurrence of either the lymphadenopathy or the pericardial effusion. The mechanism of production and the treatment of chylous effusions are poorly defined. In this case, resolution of the pericardial effusion with effective chemotherapy is postulated to have alleviated obstruction of anterograde lymphatic flow facilitating drainage into the systemic venous system and allowing for spontaneous complete resolution of the pericardial effusion without surgical intervention.

Clinical approach and review of causes of a chylothorax

A chylothorax, also known as chylous pleural effusion, is an uncommon cause of pleural effusion with a wide differential diagnosis characterized by the accumulation of bacteriostatic chyle in the pleural space. The pleural fluid will have either or both triglycerides >110 mg/dL and the presence of chylomicrons. It may be encountered following a surgical intervention, usually in the chest, or underlying disease process. Management of a chylothorax requires a multidisciplinary approach employing medical therapy and possibly surgical intervention for post-operative patients and patients who have failed medical therapy. In this review, we aim to discuss the anatomy, fluid characteristics, etiology, and approach to the diagnosis of a chylothorax.

CT Lymphangiography (CTL) in Primary Intestinal Lymphangiectasia (PIL): A Comparative Study with Intraoperative Enteroscopy (IOE)

RATIONALE AND OBJECTIVES

To investigate the clinical feasibility of CT lymphangiography (CTL) in primary intestinal lymphangiectasia (PIL) by comparison with intraoperative enteroscopy (IOE) during exploratory laparotomy.

MATERIALS AND METHODS

Eleven PIL patients (F/M, two/nine, age range 10-37 years) were recruited in this study, and they were performed IOE during exploratory laparotomy for suspected serious lymphatic-intestinal leakages. All the patients were performed CTL before surgery, and the imaging data were reviewed by two radiologists separately. CTL assessments included intestinal lesions, edematous lesions, intestinal and mesenteric lymphangiectasia, lymphaticabdominal leakages, lymph fluid reflux, lymphangioma and abnormal lymphatics in other area. The intestinal lymphangiectasia and lymphaticintestinal leakages were confirmed by histology and IOE.

RESULTS

For CTL, (1) nine intestinal wall thickening; (2) eight ascites, complicated with four pleural effusions, (3) eight intestinal and mesenteric lymphangiectasia, (4) six lymph fluid reflux (5) one lymphatic-abdominal leakage, (6) two lymphangioma. While for IOE, intestinal lymphangiectasia has been confirmed in all patients, including five segemental and six diffusive lesions in intestinal mucosa. Besides, one lymphatic-intestinal fistula, one lymphatic-abdominal leakage was confirmed. Compared to IOE and histology, the accuracy of CTL was 72.7% in detecting intestinal lymphangiectasia.

CONCLUSION

Compared to IOE, CTL demonstrates feasibility in detection of intestinal lymphangiectasia and other abnormalities in whole lymphatic circulation for PIL. Combination of CTL with IOE accommodates guidance for preoperative evaluation and therapeutic management for PIL.

Diagnosis, assessment, and management of surgical complications following esophagectomy

Despite improvements in operative strategies for esophageal resection, anastomotic leaks, fistula, postoperative pulmonary complications, and chylothorax can occur. Our review seeks to identify potential risk factors, modalities for early diagnosis, and novel interventions that may ameliorate the potential adverse effects of these surgical complications following esophagectomy.

Nonthrombotic Pulmonary Embolism From Inorganic Particulate Matter and Foreign Bodies

Nonthrombotic pulmonary embolism (NTPE) is a complete or partial occlusion of the pulmonary vasculature by various organic and inorganic materials. These materials include organic particulate matter (PM) such as adipocytes, tumor cells, bacteria, fungi, or gas and inorganic PM. Although NTPE due to organic PM has been extensively reported in the medical literature, there are no comprehensive reviews of inorganic material embolizing to the lungs. The purpose of this article is to examine the current literature describing NTPE resulting from inorganic PM and foreign bodies. Cases of NTPE are uncommon and often difficult to diagnose. The diagnosis is challenging due to its varied presentation, clinical features, and unusual radiologic features. In contrast to the "classic" pulmonary thromboembolism, the pathophysiologic effects of embolism by PM are not only mechanical but also a consequence of the nature of the offending material. NTPE caused by these substances can be relatively innocuous, life-threatening, or lead to chronic pulmonary disease, if left undetected. We hope that the heightened sense of awareness of this entity may allow earlier diagnosis and recognition of its complications.

Experience of Lymphangiography as a Therapeutic Tool for Lymphatic Leakage After Kidney Transplantation

INTRODUCTION

Lymphatic leakage after kidney transplantation is a relatively frequent complication but sometimes resistant to treatment, and there is no fixed treatment algorithm. The effectiveness of therapeutic lymphangiography for postoperative lymphatic or chyle leakage has been reported, but few reports are available regarding patients who have undergone kidney transplantation. In this study, we report our experience with lymphangiography as a therapeutic tool for lymphatic leakage after kidney transplantation.

PATIENTS AND METHODS

Intranodal lymphangiography for lymphatic leakage was performed in 4 patients (3 male, 1 female; age range, 38 to 70 years old) after living kidney transplantation at the Osaka City University Hospital in Japan. The amount of drainage before lymphangiography was 169 to 361 mL/day. The procedure for intranodal lymphangiography was as follows: the inguinal lymph node was punctured under ultrasound guidance, and the tip of the needle was instilled at the junction between the cortex and the hilum, after which Lipiodol was slowly and manually injected.

RESULTS

Lymphangiography was technically successful in 3 out of the 4 patients. In all successful cases, the amount of drainage decreased and leakage finally stopped without additional therapy such as sclerotherapy or fenestration. In 2 cases, we were able to directly detect the leakage site using lymphangiography. The time between lymphangiography and leakage resolution ranged from 8 to 13 days. There were neither complications of lymphangiography nor recurrence of lymphatic leakage in the successful cases.

CONCLUSIONS

Intranodal lymphangiography may be not only a diagnostic tool but also an effective, minimally-invasive, and safe method for treatment of lymphatic leakage resistant to drainage after kidney transplantation.

Unilateral pedal lymphangiography plus computed tomography angiography for location of persistent idiopathic chyle leakage not detectable by ordinary contrast computed tomography

Background

To identify the value of unilateral pedal lymphangiography (LPG) plus computed tomography angiography (CTA) in accurate depiction of persistent idiopathic chyluria undetectable by ordinary contrast CT.

Methods

Eighteen patients 44–63 years of age with persistent idiopathic chyluria who failed conservative management were included. Ordinary CT had not revealed a chyle leak. Cystoscopy, unilateral LPG, and post-LPG CT angiography (CTA) were sequentially performed. Ligation and stripping of the perirenal lymphatics were subsequently performed guided by lymphangiography and CTA.

Results

LPG and post-LPG CTA detected 17 unilateral and one bilateral chyle leaks in the 18 patients, with clear images of the communication of lymphatic vessels and the renal collecting or vascular system. The success rate was significantly better than cystoscopy (100% vs 50.0%, P = 0.005) or LPG alone (100% vs. 72.2%, P = 0.016). Chyluria resolved after surgery in all patients; no relapses were found.

Conclusions

LPG plus post-LPG CTA accurately characterized perirenal lymphangiectasia that was not demonstrated by routine contrast-enhanced CT or not suitable for magnetic resonance imaging. Despite of its invasiveness, this method is a good diagnostic alternative to LPG in patients with persistent chyluria requiring surgery.

Modern Techniques of Lymphangiography and Interventions: Current Status and Future Development

One of the crucial functions of the lymphatic system is maintenance of fluid balance. Nonetheless, due to lack of clinical imaging and interventional techniques, the lymphatic system has been under the radar of the medical community. The recently developed intranodal lymphangiography and dynamic contrast-enhanced MR lymphangiography provide new insight into lymphatic pathology. Thoracic duct embolization has become the method of choice for the treatment of patients with chylous leaks. Interstitial lymphatic embolization further expanded the lymphatic embolization approaches. Liver lymphatic lymphangiography and embolization allow treatment of postsurgical liver lymphorrhea and protein-losing enteropathy. The potential for further growth of lymphatic interventions is vast and includes liver lymphatic procedures and advanced thoracic duct interventions, such as thoracic duct externalization and stenting. These current and future advances will open up a realm of new treatments and diagnostic opportunities.

Computed tomography lymphangiography findings in 27 cases of lymphangioleiomyomatosis

Background Lymphangioleiomyomatosis (LAM) is a rare disease involving the bronchi, lymphatic vessels, and veins. However, there are few reports about lymphatic vessel abnormalities associated with LAM. Purpose To evaluate computed tomography (CT) lymphangiography findings in cases of LAM, especially lymphatic vessel abnormalities. Material and Methods Twenty-seven patients with LAM underwent direct lymphangiography (DLG), followed by a post-procedural thoracoabdominal CT examination. Results All 27 patients were diagnosed with LAM, including 25 (93%) with chylothorax, eight (30%) with chyloperitoneum, seven (26%) with chylous fluid in the chest and abdomen, and one (4%) with lower-limb lymphedema. The CT lymphangiography showed that 27/27 (100%) patients presented iliac or retroperitoneal lymphatic vessel dilation; 20/27 (74%) presented thoracic duct outlet obstruction; 9/27 (33%) presented pleural lymph leakage; and 13/27 (48%) presented an abnormal distribution of contrast agent in the contralateral lumbar trunk, 3/27 (11%) in the pulmonary field, 1/27 (4%) in the abdominal cavity, and 4/27 (15%) in the pelvic cavity. Five of the 27 patients (19%) had retroperitoneal lymphangioleiomyomas, with contrast agent accumulation in three cases during CT lymphangiography. Two of the 27 (7%) patients had enlarged lymph nodes in the retroperitoneum. All 27 patients (100%) diagnosed with LAM displayed various lung cysts on thoracic high-resolution CT scans. Conclusion CT lymphangiography findings can be used to diagnose most LAM cases accurately. Moreover, these findings also display the various lymphatic vessel abnormalities associated with LAM.

Lymphoscintigraphy for Imaging of the Lymphatic Flow Disorders

Lymphoscintigraphy has introduced with the great advantage for diagnostic imaging of the lymphatic flow disorders. Lymphoscintigraphy can be performed in patients of any age, including neonates, and even in patient in critical conditions. The procedure is quite simple, and it needs only subcutaneous injection of small amounts of radiotracers. From subcutaneous tissue the radiotracer is taken by the lymphatic vessels and gives off energy in the form of gamma radiation detected by a gamma camera. Radiotracers rarely cause the allergic reaction and can be administered to the patients with allergy to iodine contrast media. Comparing with the Lipiodol, radiotracers cannot cause pulmonary embolism; therefore, it is safe for the patients with respiratory dysfunction. The objective of this article is to describe the indication, technique, equipment, pitfalls, safety, and effectiveness of lymphoscintigraphy for imaging of the lymphatic flow disorders.

Percutaneous Treatment of Chylous Ascites

Chylous ascites occurs as a result of lymphatic leakage, which contains high concentration of triglycerides. The leakage is caused by various benign or malignant etiologies ranging from congenital lymphatic abnormality to trauma. Lymphangiography has been shown to be effective in the diagnosis of lymphatic leakage and has also been reported to have therapeutic outcome. The development of intranodal technique for lymphangiography has recently made the procedure more widespread. As an adjunctive procedure, percutaneous embolization may be performed which involves use of embolic agents such as N-butyl cyanoacrylate and coil to occlude the leak. Embolization in the lymphatic system was first made popular by the introduction of thoracic duct embolization by Cope et al and has recently led to the development of various techniques for percutaneous embolization. This article reviews the options and techniques for percutaneous treatment of lymphatic leaks in patients presenting with chylous ascites.

The thoracic duct: clinical importance, anatomic variation, imaging, and embolization

The thoracic duct is the body's largest lymphatic conduit, draining upwards of 75 % of lymphatic fluid and extending from the cisterna chyli to the left jugulovenous angle. While a typical course has been described, it is estimated that it is present in only 40-60% of patients, often complicating already challenging interventional procedures. The lengthy course predisposes the thoracic duct to injury from a variety of iatrogenic disruptions, as well as spontaneous benign and malignant lymphatic obstructions and idiopathic causes. Disruption of the thoracic duct frequently results in chylothoraces, which subsequently cause an immunocompromised state, contribute to nutritional depletion, and impair respiratory function. Although conservative dietary treatments exist, the majority of thoracic duct disruptions require embolization in the interventional suite. This article provides a comprehensive review of the clinical importance of the thoracic duct, relevant anatomic variants, imaging, and embolization techniques for both diagnostic and interventional radiologists as well as for the general medical practitioner.

KEY POINTS

• Describe clinical importance, embryologic origin, and typical course of the thoracic duct. • Depict common/lesser-known thoracic duct anatomic variants and discuss their clinical significance. • Outline the common causes of thoracic duct injury and indications for embolization. • Review the thoracic duct embolization procedure including both pedal and intranodal approaches. • Present and illustrate the success rates and complications associated with the procedure.