Computed Tomography Lymphangiography Research Articles

Lymphatic plastic bronchitis and primary chylothorax: A study based on computed tomography lymphangiography.

This study presents an evaluation of the computed tomography lymphangiography (CTL) features of lymphatic plastic bronchitis (PB) and primary chylothorax to improve the diagnostic accuracy for these two diseases. To improve the diagnosis of lymphatic PB or primary chylothorax, a retrospective analysis of the clinical features and CTL characteristics of 71 patients diagnosed with lymphatic PB or primary chylothorax was performed. The clinical and CTL data of 71 patients (20 with lymphatic PB, 41 with primary chylothorax, and 10 with lymphatic PB with primary chylothorax) were collected retrospectively. CTL was performed in all patients. The clinical manifestations, CTL findings, and conventional chest CT findings of the three groups of patients were compared. The chi-square test or Fisher's exact test was used to compare the differences among the three groups. A difference was considered to be statistically significant when P < 0.05. (1) The percentages of abnormal contrast medium deposits on CTL in the three groups were as follows: Thoracic duct outlet in 14 (70.0%), 33 (80.5%) and 8 (80.0%) patients; peritracheal region in 18 (90.0%), 15 (36.6%) and 8 (80.0%) patients; pleura in 6 (30.0%), 33 (80.5%) and 9 (90.0%) patients; pericardium in 6 (30.0%), 6 (14.6%) and 4 (40.0%) patients; and hilum in 16 (80.0%), 11 (26.8%) and 7 (70.0%) patients; and (2) the abnormalities on conventional chest CT in the three groups were as follows: Ground-glass opacity in 19 (95.0%), 18 (43.9%) and 8 (80.0%) patients; atelectasis in 4 (20.0%), 26 (63.4%) and 7 (70.0%) patients; interlobular septal thickening in 12 (60.0%), 11 (26.8%) and 3 (30.0%) patients; bronchovascular bundle thickening in 14 (70.0%), 6 (14.6%) and 4 (40.0%) patients; localized mediastinal changes in 14 (70.0%), 14 (34.1%), and 7 (70.0%) patients; diffuse mediastinal changes in 6 (30.0%), 5 (12.2%), and 3 (30.0%) patients; cystic lesions in the axilla in 2 (10.0%), 6 (14.6%), and 2 (20.0%) patients; and cystic lesions in the chest wall in 0 (0%), 2 (4.9%), and 2 (4.9%) patients. CTL is well suited to clarify the characteristics of lymphatic PB and primary chylothorax. This method is an excellent tool for diagnosing these two diseases.

Contrast-enhanced and indirect computed tomography lymphangiography accurately identifies the cervical lymphocenter at risk for metastasis in pet dogs with spontaneously occurring oral neoplasia.

For dogs with oral tumors, cervical lymph node (LN) metastasis alters treatment and prognosis. It is therefore prudent to make an accurate determination of the clinical presence (cN+ neck) or absence (cN0 neck) of metastasis prior to treatment. Currently, surgical LN extirpation with histopathology is the gold standard for a diagnosis of metastasis. Yet, recommendations to perform elective neck dissection (END) for staging are rare due to morbidity. Sentinel lymph node (SLN) mapping with indirect computed tomography lymphangiography (ICTL) followed by targeted biopsy (SLNB) is an alternative option to END. In this prospective study, SLN mapping followed by bilateral END of all mandibular LNs (MLNs) and medial retropharyngeal LNs (MRLNs) was performed in 39 dogs with spontaneously occurring oral neoplasia. A SLN was identified by ICTL in 38 (97%) dogs. Lymphatic drainage patterns were variable although most often the SLN was identified as a single ipsilateral MLN. In the 13 dogs (33%) with histopathologically confirmed LN metastasis, ICTL correctly identified the draining lymphocentrum in all (100%). Metastasis was confined to the SLN in 11 dogs (85%); 2 dogs (15%) had metastasis beyond the SLN ipsilaterally. Contrast enhanced CT features had good accuracy in predicting metastasis, with short axis measurements less than 10.5 mm most predictive. ICTL imaging features alone were unable to predict metastasis. Cytologic or histopathologic SLN sampling is recommended prior to treatment to inform clinical decision-making. This is the largest study to show potential clinical utility of minimally invasive ICTL for cervical LN evaluation in canine oral tumors.

Intranodal dynamic contrast-enhanced CT lymphangiography and dynamic contrast-enhanced MR lymphangiography in microminipig.

To evaluate the feasibility and image quality of intranodal dynamic contrast-enhanced CT lymphangiography (DCCTL) and dynamic contrast-enhanced MR lymphangiography (DCMRL) in microminipigs. Our institution's committee for animal research and welfare provided approval. Three microminipigs underwent DCCTL and DCMRL after inguinal lymph node injection of 0.1mL/kg contrast media. Mean CT values on DCCTL and signal intensity (SI) on DCMRL were measured at the venous angle and thoracic duct (TD). The contrast enhancement index (CEI; increase in CT values pre- to post-contrast) and signal intensity ratio (SIR; SI of lymph divided by SI of muscle) were evaluated. The morphologic legibility, visibility, and continuity of lymphatics were qualitatively evaluated using a 4-point scale. Two microminipigs underwent DCCTL and DCMRL after lymphatic disruption and the detectability of lymphatic leakage was evaluated. The CEI peaked at 5-10min in all microminipigs. The SIR peaked at 2-4min in two microminipigs and at 4-10min in one microminipig. The peak CEI and SIR values were 235.6 HU and 4.8 for venous angle, 239.4 HU and 2.1 for upper TD, and 387.3 HU and 2.1 for middle TD. The visibility and continuity of upper-middle TD scores were 4.0 and 3.3-3.7 for DCCTL, and 4.0 and 4.0 for DCMRL. In the injured lymphatic model, both DCCTL and DCMRL demonstrated lymphatic leakage. DCCTL and DCMRL in a microminipig model enabled excellent visualization of central lymphatic ducts and lymphatic leakage, indicating the research and clinical potential of both modalities. • Intranodal dynamic contrast-enhanced computed tomography lymphangiography showed a contrast enhancement peak at 5-10min in all microminipigs. • Intranodal dynamic contrast-enhanced magnetic resonance lymphangiography showed a contrast enhancement peak at 2-4min in two microminipigs and at 4-10min in one microminipig. • Both intranodal dynamic contrast-enhanced computed tomography lymphangiography and dynamic contrast-enhanced magnetic resonance lymphangiography demonstrated the central lymphatic ducts and lymphatic leakage.

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

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

Systematic lymphatic abnormality-related osseous lesions: a study based on CT lymphangiography.

BackgroundFew studies have focused on the morphology of systematic lymphatic abnormality-related osseous lesions. In this study, we classified systematic lymphatic abnormality-related osseous lesions into four types based on their morphology and density. We also discussed the imaging features of computed tomography lymphangiography (CTL) in this disease.MethodsIn this retrospective cohort study, the clinical and imaging data of 39 patients with systematic lymphatic abnormality-related osseous lesions were collected. All patients underwent computed tomography (CT) scans of the chest and abdomen after direct lymphangiography, and two experienced radiologists evaluated the CTL features of intraosseous and extraosseous lymphatic vessel abnormalities.ResultsIntraosseous osteolytic changes were observed in all 39 patients. According to the morphological density of the lesions, systematic lymphatic abnormality-related osseous lesions were classified into four types: cyst-like (76.9%), canal-like or honeycomb-like (87.2%), osteoporosis-like (41.0%), and osteosclerosis-like (20.5%), with abnormal deposits of lipiodol seen in the first two types. Enhanced CT of the thorax and abdomen was performed in 11 cases, and enhancement was not seen in any intraosseous lesions.ConclusionsThe CTL features of systematic lymphatic abnormality-related osseous lesions have specific characteristics and are often accompanied by extraosseous abnormalities, which can provide a vital imaging basis for the diagnosis and differentiation of this disease.

Prospective evaluation of lymphatic embolization as part of the treatment in dogs with presumptive idiopathic chylothorax.

To describe the embolization technique and short-term clinical outcome in dogs undergoing lymphatic embolization (LE) as part of treatment for presumptive idiopathic chylothorax (IC). Additionally, to document findings in computed tomography lymphangiography (CTLa) following embolization. Prospective case series. Eight client-owned dogs. Dogs underwent CTLa followed by thoracic duct ligation (TDL), pericardiectomy (PC) and LE. A mixture of 3:1 lipiodol: n-butyl cyanoacrylate embolic solution was injected through a catheterized mesenteric lymphatic vessel via limited abdominal approach using intraoperative fluoroscopy. CTLa was scheduled for 12 weeks postoperatively, and long-term follow-up was obtained via telephone contact. LE was technically successful in six of the eight dogs; and clinically successful in five of the six dogs. In the unsuccessful dog, a diagnosis of lymphangiosarcoma was determined, and the owners elected for euthanasia. Five dogs who underwent successful LE underwent CTLa at 12 weeks. Complete resolution of pleural effusion occurred in three dogs and scant pleural effusion in two dogs. A robust lymphatic embolus preventing antegrade continuation of radiocontrast was documented in all five dogs. Five of the six dogs that underwent LE, were alive and clinically normal at 358-960 days postoperatively. LE is a feasible part of treatment for dogs with IC. Additionally, a robust lymphatic embolus and lack of radiocontrast flow past the embolus was documented at 12 weeks following surgery. LE has the potential to reduce surgical failure by reducing efferent lymphatic chyle flow, occluding missed lymphatic branches and preventing the development of collateral branches.

Abstract No. 22 Water-soluble pediatric ultra-high resolution computed tomography lymphangiography

To describe a novel lymphatic imaging technique: pediatric ultra-high resolution CT lymphangiography (UHR CTL) with water-soluble iodinated contrast via direct inguinal intranodal injection. UHR CTL is particularly beneficial in complex congenital heart disease patients with postoperative high-mortality continuous chylothorax and right-to-left shunt.

Computed tomography lymphangiography via intrametatarsal pad injection is feasible in cats with chylothorax.

To evaluate the feasibility of CT lymphangiography via intrametatarsal pad injection in cats with chylothorax. 7 client-owned cats. This was a multicenter, retrospective, descriptive study. Medical records and imaging data from 4 veterinary hospitals were reviewed to identify cats with chylothorax that had undergone intrametatarsal pad injection via CT lymphangiography. In total, 7 client-owned cats were included in the study. Signalment, history, image findings, and follow-up data were recorded. Descriptive statistics were used to analyze the success rate of thoracic duct (TD) enhancement and describe relevant clinical findings. Enhancement of TDs was successful in 6 of the 7 cats within 5 to 15 minutes after initiating intrametatarsal pad injection under general anesthesia. Successful migration of contrast medium into the lymphatic vessels cranial to the popliteal lymph nodes was observed in all cats within 5 minutes after injection. The recommended dose of contrast medium to achieve TD enhancement was 1 mL/kg (0.5 mL/kg/pad; concentration, 350 mg of iodine/kg). Only 1 cat had mild swelling of the paws after the procedure, and it recovered quickly without pain medication; no cats experienced lameness. Similar to dogs and unlike in previously published reports, 72% of TD branches were located in the right hemithorax. CT lymphangiography via intrametatarsal pad injection is a feasible and safe procedure for cats with chylothorax. This technique provides detailed information regarding the unique TD anatomy and cisterna chyli location. It also contributes to surgical planning.

Effect of contrast agent viscosity and massage on success of computed tomography lymphangiography with aqueous contrast for sentinel lymph node identification in healthy dogs.

Sentinel lymph node (SLN) evaluation is important for accurate cancer staging. Computed tomography (CT) lymphangiography with aqueous contrast is a feasible technique for SLN identification in dogs. Although most studies report success rates around 90%, success rates as low as 60% have been reported. One reason for low success rates may be the difference in viscosity of the various agents used in comparison to normal lymph viscosity. The objective of this study was to evaluate contrast agents of differing viscosities for use in CT lymphangiography for SLN identification and to determine the influence of massage on contrast flow rates. The hypothesis was that lower viscosity agents would have a higher success rate and faster time to identification of the SLN than higher viscosity agents and that massage would increase contrast flow rates. Dogs were anaesthetised and CT lymphangiography was performed with four contrast agents of differing viscosities in a randomized crossover design. Injections were made on the dorsal pes bilaterally on two study days and the popliteal lymph nodes were evaluated for contrast uptake. There was no significant difference in success of SLN identification or time to SLN identification among the four agents. Massage of the injection site increased rate of contrast flow through the lymphatics. No specific recommendation for one contrast agent over another can be made with these results. Massage is recommended to improve lymphatic flow when performing CT lymphangiography with aqueous contrast in dogs.

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.

Dynamic contrast-enhanced computed tomography lymphangiography with intranodal injection of water-soluble iodine contrast media in microminipig: imaging protocol and feasibility.

To evaluate the optimal imaging protocol and the feasibility of intranodal dynamic contrast-enhanced computed tomography lymphangiography (DCCTL) in microminipigs. The Committee for Animal Research and Welfare provided university approval. Five female microminipigs underwent DCCTL after inguinal lymph node injection of 0.1mL/kg of iodine contrast media at a rate of 0.3mL/min with three different iodine concentrations: group 1, 75mgI/mL; group 2, 150mgI/mL; and group 3, 300mgI/mL. The CT values of the venous angle, thoracic duct (TD), cisterna chyli, iliac lymphatic duct, and iliac lymph node were measured; increases in CT values pre- to post-contrast were assessed as the contrast-enhanced index (CEI). Multi-detector row CT (MDCT) and volume rendering images showing the highest CEI were qualitatively evaluated. The CEI of all lymphatics peaked at 5-10min. The mean CEI of TD at 10min of group 2 (193.0 HU) and group 3 (201.5 HU) were significantly higher than that of group 1 (70.7 HU) (p = 0.024). The continuity and overall diagnostic acceptability of all lymphatic system components were better in group 3 (3.6 and 3.0, respectively) than group 1 (2.6 and 1.6) and group 2 (3.0 and 2.6) (p = 0.249 and 0.204). The optimal imaging protocol for intranodal DCCTL could be dual-phase imaging at 5 and 10min after the injection of 300mgI/mL iodinated contrast media. DCCTL provided good images of lymphatics and is potentially feasible in clinical settings. • Dynamic contrast-enhanced computed tomography lymphangiography with intranodal injection of water-soluble iodine contrast media showed the highest enhancement of all lymphatics at scan delays of 5 and 10min. • The optimal iodine concentration for intranodal dynamic contrast-enhanced computed tomography lymphangiography might be 300mgI/mL. • Intranodal dynamic contrast-enhanced computed tomography lymphangiography provided good images of all the lymphatic system components and is potentially feasible in clinical settings.

Canine tonsillar neoplasia and tonsillar metastasis from various primary neoplasms.

Tonsillar metastasis from distant primary tumours has not been described in dogs, and reports are rare in humans. The aims of this study were to determine whether tumour metastasis occurs to the canine palatine tonsils and evaluate whether afferent lymphatics drain to the palatine tonsils via skull indirect computed tomography lymphangiography (ICTL). Retrospective review of the diagnostic laboratory tonsillar histopathology submissions was performed. ICTL studies (n = 53) were retrospectively reviewed by a single radiologist. Of 882 total tonsil histopathology samples, 492 (56%) were considered neoplastic, with 8% of them benign. Of the primary malignant neoplasms of the tonsil, squamous cell carcinoma (55%), lymphoma (17%) and melanoma (12%) were most common. Tonsillar metastasis was confirmed in 41 cases; histopathologic evaluation revealed melanoma (25), carcinoma (10), hemangiosarcoma (2) and one each of fibrosarcoma, malignant histiocytosis, basal cell tumour and undifferentiated sarcoma. A total of 53 tonsillar melanoma cases were identified, of which 25 represented metastasis from a known distant primary tumour and 28 were solely tonsillar, with 9 of these cases having concurrent lymph node metastasis. No ICTL cases had lymphatic contrast drainage to the palatine tonsil. The palatine tonsil is an important site of metastasis for a variety of primary tumour types from many locations. ICTL did not reveal lymphatics draining to the palatine tonsil, which is highly supportive of hematogenous route of metastasis to the tonsil. Tonsillar metastasis may be more common than previously thought. It is recommended to perform a thorough oral examination, including the tonsils, for all oral tumours and melanoma cases.

Computed tomographic lymphangiography via intra-metatarsal pad injection is feasible in dogs with chylothorax.

Lymphangiography can be useful for preoperative planning in chylothorax. Conventional ultrasound-guided intranodal injection can be difficult in some cases and is dependent upon operator skill. Alternative methods have been proposed to simplify the procedure, but their feasibility has not been sufficiently evaluated in clinical cases. The primary purpose of this multicenter, retrospective, descriptive study was to assess the feasibility and describe the clinical findings of CT lymphangiography by intrametatarsal pad injection in dogs with naturally occurring chylothorax. Twenty dogs were analyzed, and enhancement of thoracic ducts (TDs) was successful in 18 (90%) dogs within 5-14 min after initiating the injection, while successful enhancement of the lymphatic vessels cranial to the popliteal lymph nodes was seen in all dogs within 5 min after injection. The dose with good success to achieve TD enhancement was 1mL/kg (concentration 350mg I/kg). Only two dogs had mild discomfort after recovery from general anesthesia. Computed tomography lymphangiography by intrametatarsal pad injection is a feasible, easy, and safe procedure, which could provide adequate TD and cisterna chyli enhancement, identify TD number and cisterna chyli location and structure, and contribute to surgical planning.

Use of indirect computed tomography lymphangiography to determine metastatic status of sentinel lymph nodes in dogs with a pre-operative diagnosis of melanoma or mast cell tumour.

Canine melanomas and mast cell tumours (MCTs) frequently metastasize to lymph nodes, worsening prognosis compared with dogs without metastasis. Sentinel lymph node (SLN) evaluation is more specific than evaluation of the lymph node closest to the tumour, which may not be the draining lymph node. Computed tomography lymphangiography (CTL) allows for SLN identification and one study of canine mammary tumours found that CTL was able to assist in determination of the metastatic status of inguinal SLNs prior to extirpation and histopathology. The objective of the present study was to evaluate CTL for use in determining metastasis to the SLN in dogs with a pre-operative diagnosis of melanoma or MCT in various locations by correlating CTL findings with histopathology. The hypothesis was that CTL would not be able to determine the metastatic status of lymph nodes, based on author experience. Dogs were prospectively enrolled and underwent CTL and subsequent SLN extirpation. Histopathology results for the primary tumour, SLN, and additional extirpated lymph nodes were recorded. Fifteen dogs were enrolled and 21 SLN were evaluated. The SLN enhancement pattern (heterogeneous, homogenous or peripheral) was not associated with metastasis, nor was the attenuation value at 1 minute, 5 minutes, or the change in attenuation value. No correlation was found between CTL findings and metastatic status of SLNs. Based on these results, CTL alone cannot be used to diagnose SLN metastasis. Extirpation of the SLN with histopathology is recommended to diagnose lymph node metastasis in dogs with melanoma and MCT.

Diagnosis of Lymphangiomatosis: A Study Based on CT Lymphangiography

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). 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. (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. 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.

Video‐assisted thoracoscopic thoracic duct sealing is inconsistent when performed with a bipolar vessel‐sealing device in healthy cats

To describe a technique for video-assisted thoracoscopic (VATS) thoracic duct ligation (TDL) in normal cats with a bipolar vessel-sealing device and to assess durability of the seal. Prospective case series. Six healthy research cats. Cats were placed under anesthesia for computed tomography lymphangiography (CTLA) to identify thoracic duct anatomy. On the basis of CTLA findings, cats were positioned in either right or left lateral recumbency for a 3-port VATS TDL. Thoracic duct branches were dissected from the aorta after subcutaneous indirect near-infrared fluorescence (NIRF) lymphography with indocyanine green was performed to optimize detection. A vessel-sealing device was used to seal each thoracic duct in 1 or more locations. Postattenuation, indirect NIRF lymphography was repeated to confirm complete occlusion of thoracic duct flow. CTLA was repeated in all cats 3 months postoperatively. The thoracic duct was surgically approached from the right in 3 cats and from the left in 3 cats. A median of 2.5 (range 1-6) TDL seal sites were applied. In 2 cats, leakage of chyle was detected during dissection. At 3 months postoperatively, CTLA confirmed reestablished chylous flow in 5 of 6 cats, appearing to occur through recanalization of previously sealed sites rather than through development of de novo lymphatic vessels. VATS TDL is feasible in cats, although the variable and delicate nature of feline thoracic duct anatomy should be considered preoperatively. Bipolar vessel-sealing devices are not a durable modality for thoracic duct sealing in healthy cats in a seal only fashion.

Indirect computed tomography lymphangiography with aqueous contrast for evaluation of sentinel lymph nodes in dogs with tumors of the head.

Sentinel lymph node evaluation is widely used in human medicine to evaluate the first lymph node(s) to which a tumor drains. Sentinel lymph node biopsy allows avoidance of extensive lymphadenectomies in cases where the sentinel lymph node is negative for metastasis, thereby reducing patient morbidity. It has been shown that regional lymph nodes are not always the sentinel lymph node, thus identification and sampling of sentinel lymph nodes allows for more accurate staging, which is critical for treatment and prognostication in dogs with cancer. The objective of this prospective, pilot study was to determine if indirect computed tomography (CT) lymphangiography with aqueous contrast agent would successfully allow identification of sentinel lymph nodes in dogs with masses on the head. Eighteen dogs underwent CT lymphangiography. The sentinel lymph node was successfully identified within 3 min of contrast injection in 16 dogs (89%). Compression of lymphatic vessels from endotracheal tube ties and/or the patient's own body weight delayed or prevented identification of sentinel lymph nodes in two dogs (11%). Computed tomography lymphangiography with aqueous contrast can be used successfully to rapidly identify sentinel lymph nodes in dogs with masses on the head.

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.

Computed Tomography-Guided Access to the Cisterna Chyli: Introduction of a Technique for Direct Lymphangiography to Evaluate and Treat Chylothorax

The purpose of this report is to introduce a technique of direct lymphangiography to enable chylothorax treatment. Using a hybrid computed tomography (CT) and fluoroscopy imaging system, a 21-gauge needle was placed under CT guidance into the cisterna chyli to allow contrast lymphangiography and CT lymphangiography in two patients with presumed postoperative chylothorax. Water-soluble contrast media injection demonstrated the thoracic duct anatomy in both patients. Further successful needle disruption of the cisterna chyli was performed in one patient to interrupt lymph flow and stop the chylous leak, with subsequent resolution of the chylothorax.