Radiographic evaluation of subcutaneously injected, water-soluble, iodinated contrast for lymphography

Abstract

17Sentinel lymph node (SLN) mapping is common in many types of human cancers, and is 18 gaining utility in veterinary medicine. There are currently many different methods described in 19 veterinary medicine for pre-operative SLN mapping, however, most of these are restricted to 20 referral institutions due to cost and need for specialized equipment. The purpose of this 21 prospective, pilot study was to evaluate the feasibility of radiographic evaluation of water-22 soluble, iodinated contrast (WIC) injected subcutaneously for lymphography in dogs. Eight dogs 23 were injected with 1-2 milliliters of WIC into the subcutaneous tissues overlying the tarsus in 4 24 separate locations mimicking a circumferential, peri-tumoral injection. Radiographs were taken 25 at select time points up to 50 minutes. Image sequences were evaluated by a single, board-26 certified radiologist. All 8 dogs had visible contrast-enhancing lymphatic channels. Median time 27 to lymphatic enhancement was immediately post-injection. Seven dogs (88%) had 8 contrast 28 enhancing lymph nodes (7 popliteal and 1 superficial inguinal). Median time to lymph node 29 enhancement was 20 minutes. In this study, the plantar aspect of the pes drained to the 30 superficial inguinal lymph node, and the dorsal aspect of the pes drained to the popliteal lymph 31 node. Subcutaneously-injected WIC was readily identifiable in the lymphatic channels and 32 draining lymph node(s). Subcutaneously injected WIC may offer a practical alternative to 33 previously described pre-operative methods of SLN mapping. Additionally, one cannot assume 34 that the popliteal lymph node alone, drains the distal pelvic limb.35

<strong></strong> A Manual and Machine Learning Based Case Investigations for Detecting the Lymphatic Spread of Canine Cancers

“…The lymph drainage pattern and SLN found in the mammary carcinoma detected through Lipiodol ultra-fluid and MB are congruent with earlier reports (Chioreanet al, 2016; Lee et al, 2018;Manfredi et al, 2021). Timing of radiograph are zero (0),2, 5,30,60 min and 2, 24 and, 72 hours interval same as in Patsikas et al2006 but further drainage to second-tier nodes as in Collivignarelli et al2021 is because captured images at 24h interval with the subcutaneous route.…”

“…Currently, several IL methods are used for assessing the lymphatic and lymph nodes draining the primary tumor mass. Those are vital blue dyes for visual detection (Mayer et al,2013;Brissot and Edery, 2016), radiocolloid lymphoscintigraphy (Hlusko et al, 2020;Manfredi et al, 2021), radiographic lymphography (Mayer et al,2013;Lee et al, 2018;Collivignarelli et al,2021), computed tomography (CT), lymphography (Sarowitz et al, 2017;Grimes et al, 2017;Majeski et al, 2017;Rossi et al,2018;Lapsley et al, 2020), fluorescent optical imaging or Near-infrared imaging (NIR) (Iida et al, 2913;Wan et al,2021;Beer et al,2022), contrast-enhanced ultrasound (CEUS) (Gelb et al,2010;Fournier et al, 2020), photoacoustic imaging(Garcia-Uribe et al, 2015), SPECT/PET CT (Beer et al, 2018;LeBlanc et al, 2013), Magnetic resonance (MR) lymphography (Turkbey et al, 2015), hybrid tracer (Nyberg et al, 2011), and nanocarriers (Jain et al, 2009). Manual detection of various types of cancerous tissues of canine patients is tedious process.…”