Superficial anatomic landmarks can be used to triangulate the location of canine peripheral lymphocentrums: superficial cervical, axillary, and superficial inguinal.

OBJECTIVE: To utilize the geometry of superficial anatomic landmarks to guide incisional location and orientation for peripheral lymphadenectomy, document deep anatomic landmarks for lymphocentrum identification, and develop novel surgical approaches to the superficial cervical, axillary, and superficial inguinal lymphocentrums in dogs. ANIMALS: 12 canine cadavers. PROCEDURES: 2 cadavers were used for a pilot investigation to determine optimal body positioning, select superficial anatomic landmarks for lymphocentrum identification, and evaluate novel surgical approaches to the 3 lymphocentrums. These lymphocentrums were then dissected in 10 additional cadavers using these novel surgical approaches. Measurements of the distances from lymphocentrum to landmark and between landmarks were obtained for each lymphocentrum. Deep anatomic landmarks were recorded for each dissection. The mean and SD were calculated for each measurement and used to develop geometric guidelines for estimating the location of each lymphocentrum for these surgical approaches. RESULTS: Each peripheral lymphocentrum was found in the same location relative to the respective, predetermined, superficial, anatomic boundaries in all cadavers. Briefly, the superficial landmarks to each lymphocentrum were as follows: (1) superficial cervical: wing of atlas, acromion process of scapula, greater tubercle of humerus; (2) axillary: caudal border of transverse head of superficial pectoral muscle, caudal triceps muscle, ventral midline; and (3) superficial inguinal: origin of pectineus muscle, ipsilateral inguinal mammary gland, ventral midline. The proposed superficial and deep surgical landmarks were identified within every cadaver. The previously undescribed surgical approaches were effective for lymphocentrum identification. CLINICAL RELEVANCE: Anatomic landmarks provided in this study may help reduce surgical time and tissue trauma during peripheral lymphadenectomy in dogs. This study was also the first to describe a surgical approach to the superficial inguinal lymphocentrum and ventral approaches to the superficial cervical and axillary lymphocentrums and provided previously unpublished anatomic landmarks for a lateral approach to the superficial cervical lymphocentrum.

A narrative review on the role of carbon nanoparticles in oncology.

The lymphatic system is the first site of metastasis for most tumors and is a common reason for the failure of cancer therapy. The lymphatic system's anatomical properties make it difficult to deliver chemotherapy agents at therapeutic concentrations while avoiding systemic toxicity. Carbon nanoparticles offer a promising alternative for identifying and transporting therapeutic molecules. The larger diameter of lymphatic vessels compared to the diameter of blood vessels, allows carbon nanoparticles to selectively enter the lymphatic system once administered subcutaneously. Carbon nanoparticles stain tumor-draining lymph nodes black following intratumoral injection, making them useful in sentinel lymph node mapping. Drug-loaded carbon nanoparticles allow higher concentrations of chemotherapeutics to accumulate in regional lymph nodes while decreasing plasma drug accumulation. The use of carbon nanoparticles for chemotherapy delivery has been associated with lower mortality, fewer histopathology changes in vital organs, and lower serum concentrations of hepatocellular enzymes. This review will focus on the ability of carbon nanoparticles to target the lymphatics as well as their current and potential applications in sentinel lymph node mapping and oncology treatment regimens. This article is categorized under: Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery.

Incidence, survival time, and surgical treatment of parathyroid carcinomas in dogs: 100 cases (2010-2019).

OBJECTIVE: To evaluate outcomes of dogs with parathyroid carcinoma (PTC) treated by surgical excision and to describe the incidence of postoperative hypocalcemia, degree of hypocalcemia, duration of hospitalization, duration of calcium supplementation, and survival time. ANIMALS: 100 client-owned dogs with PTC admitted to academic, referral veterinary institutions. PROCEDURES: In a retrospective multi-institutional study, medical records of dogs undergoing surgical excision of PTC between 2010 to 2019 were reviewed. Signalment, relevant medical history, clinical signs, clinicopathologic testing, imaging, surgical findings, intraoperative complications, histologic examination, and survival time were recorded. RESULTS: 100 dogs with PTC were included, and 96 dogs had clinical or incidental hypercalcemia. Common clinical signs included polyuria (44%), polydipsia (43%), hind limb paresis (22%), lethargy (21%), and hyporexia (20%). Cervical ultrasonography detected a parathyroid nodule in 91 of 91 dogs, with a single nodule in 70.3% (64/91), 2 nodules in 25.3% (23/91), and ≥ 3 nodules in 4 (4/91)% of dogs. Hypercalcemia resolved in 89 of 96 dogs within 7 days after surgery. Thirty-four percent of dogs developed hypocalcemia, on the basis of individual analyzer ranges, within 1 week after surgery. One dog had metastatic PTC to the prescapular lymph node, and 3 dogs were euthanized for refractory postoperative hypocalcemia. Estimated 1-, 2-, and 3-year survival rates were 84%, 65%, and 51% respectively, with a median survival time of 2 years. CONCLUSIONS AND CLINICAL RELEVANCE: Excision of PTC results in resolution of hypercalcemia and excellent long-term tumor control. Surgical excision of PTC is recommended because of resolution of hypercalcemia and a good long-term prognosis. Future prospective studies and long-term follow-up are needed to further assess primary tumor recurrence, metastasis, and incidence of postoperative hypocalcemia.

Otoscopic evaluation of epithelial remnants in the tympanic cavity after total ear canal ablation and lateral bulla osteotomy.

OBJECTIVE: To determine the ability to detect the presence of epithelial remnants after total ear canal ablation (TECA) and lateral bulla osteotomy (LBO) with endoscopy and to identify the most common locations of epithelial remnants after tympanic curettage. STUDY DESIGN: Experimental study. ANIMALS: Five fresh canine cadavers with no gross evidence of middle ear disease. METHODS: Ten TECA-LBO were performed by four surgeons. After tympanic curettage, a 1.9-mm rigid 30° endoscope was inserted into the rostral, caudal, dorsal, ventral, and medial sections of the tympanic cavity. Three observers evaluated otoscopic images for epithelial remnants in each compartment. The median distribution of epithelial remnants was calculated for each section of the tympanic cavity with a three-dimensional tympanic cavity model. RESULTS: Epithelial remnants were identified in at least one of the five areas of the tympanic cavity after each TECA-LBO. The rostral section contained the most epithelial remnants (35.6%), while the medial section contained the least amount (1.8%). CONCLUSION: Use of a 1.9-mm rigid endoscope was an effective method to evaluate all sections of the tympanic cavity after curettage in TECA-LBO. Epithelial remnants were consistently found after TECA-LBO, especially in the rostral compartment. CLINICAL SIGNIFICANCE: Intraoperative endoscopy should be considered to improve removal of epithelium after initial TECA-LBO or revision surgeries.

Characterisation of peripheral blood mononuclear cell populations in periparturient dairy cows that develop metritis.

Bacterial contamination of the uterus following calving is ubiquitous in the dairy cow, 40% of cows develop postpartum uterine infection, including metritis. While predisposing factors like twinning and dystocia are associated with metritis, it is unclear why some cows remain healthy following calving and others develop uterine infection, negatively impacting animal health, milk production and economic return. Here, we profiled peripheral blood mononuclear cells of cows before calving and during postpartum metritis. We hypothesized that peripheral blood mononuclear cell function and proportions would be altered during the prepartum period in cows that develop postpartum metritis. Using flow cytometry we observed reduced proportions of peripheral CD3+/CD4+, CD4+/CD62L+, FOXP3+ and CD21+ populations from -10 to 40 days relative to calving associated with metritis, while the proportion of peripheral CD3+/CD4+ lymphocytes were specifically reduced in the prepartum period before the onset of metritis. Peripheral blood mononuclear cells from cows with metritis had a perturbed capacity to secrete IL-1ß or IFNγ in response to in vitro stimulus; cells collected during the prepartum period from cows that would go on to develop metritis failed to increase IL-1ß secretion in response to stimulation, while IFNγ secretion was altered at calving and postpartum in cows with metritis compared to healthy herd mates. No effect of metritis was observed in the capacity of cows to mount a humoral immune response to antigen administered on the day of calving. The studies discussed here suggest that while minor changes to the prepartum immune system are observed in cows that develop metritis, changes observed in the postpartum period are more prevalent and likely a consequences of disease and not causative. Future studies to modulate the prepartum immune system may help to limit postpartum metritis.