surgery small animal

BACKGROUND: Sitosterolemia, also known as phytosterolemia, is a rare recessive genetic disorder characterized by accumulation of sitosterol from vegetable oils, nuts, and other plant-based foods in the body. In those with sitosterolemia, there is an increase of fatty deposits in the arteries (atherosclerosis), which may occur in early childhood, impeding blood flow and increasing the risk of a heart attack, stroke, or sudden death at a very early age. Visual signs of sitosterolemia may include small yellowish xanthomas beginning in early childhood...

Small animal transplant models are indispensable for organ tolerance studies investigating feasible therapeutic interventions in preclinical studies. Rat liver transplantation (LTx) protocols typically use an orthotopic model where the recipients' native liver is removed and replaced with a donor liver. This technically demanding surgical procedure requires advanced micro-surgical skills and is further complicated by lengthy anhepatic and lower body ischemia times. This prompted the development of a less complicated heterotopic method that can be performed faster with no anhepatic or lower body ischemia time, reducing post-surgery stress for the recipient animal...

OBJECTIVE: High-intensity magnetic resonance-guided focused ultrasound (MRgFUS) is a non-invasive therapy to lesion brain tissue, used clinically in patients and pre-clinically in several animal models. Challenges with focused ablation in rodent brains can include skull and near-field heating and accurately targeting small and deep brain structures. We overcame these challenges by creating a novel method consisting of a craniectomy skull preparation, a high-frequency transducer (3 MHz) with a small ultrasound focal spot, a transducer positioning system with an added manual adjustment of ∼0...

Veterinary minimally invasive surgery continues to grow as a specialty. With increasing experience in this field, comes improved accessibility as well as progressive complexity of procedures performed. Advancement in technology has been both a response to the growth and a necessary driver of continued refinement of this field. Innovative research leading to advancements in surgical equipment has led to the development of novel image acquisition platforms, cannulas, smoke evacuation systems, antifog devices, instrumentation, and ligating/hemostatic devices...

Hyperbaric oxygen therapy (HBOT) is utilized as an adjunctive treatment for human and veterinary patients with compromised tissues. Medical records from two veterinary hospitals with HBOT chambers were searched for small animal veterinary dentistry and oral surgery specialty patients. The HBOT records were combined with the medical records from the referring specialty veterinary dentistry and oral surgery services. Clinical indications for HBOT treatments associated with a positive outcome in this case series included resistant bacterial infections, electrical cord injury, bite wound injuries, osteomyelitis, crush/traumatic injuries including mandibular fractures, oral surgery performed at previously irradiated sites, and osteonecrosis, presumably radiation induced...

Minimally invasive endoscopic surgery is growing in veterinary medicine, in large part, due to the advantages associated with reduced pain, potential for decreased complications, and increased visualization of structures through magnification and illumination. With advancing technologies, we can now improve upon natural "white light" endoscopy with fluorescence-guided imaging. Near-infrared (NIR) cameras allow for real-time, high-definition visualization of vessels, anatomic structures, and perfusion. New uses of NIR technologies during laparoscopy are continuing to grow for vascular, lymphatic, and oncologic-related techniques...

Intraoperative near-infrared fluorescence imaging allows for real time, noninvasive visualization of anatomic structures (blood vessels, lymphatic vessels) or diseased states (cancer, inflammation). This technique is easily adapted to thoracoscopy and has allowed for improved detection of lung tumors and other various cancers, thoracic lymphatics, and cardiothoracic vasculature.

Whole blood analysis can evaluate numerous parameters, including pH, pCO₂, pO₂, HCO₃- , base excess, glucose, electrolytes, lactate, blood urea nitrogen, creatinine, bilirubin, and hemoglobin. This valuable tool enables clinicians to make more informed decisions about patient care. However, the current body of literature describing perioperative whole blood analysis in Dorset sheep ( Ovis aries ) is small, so clinicians lack adequate information to guide their decision-making when evaluating test results...

Hiatal hernias result from a widening of the esophageal hiatus that leads to the displacement of the lower esophageal sphincter and stomach into the thoracic cavity. Clinical signs of regurgitation, gastroesophageal reflux, and esophagitis are managed medically, but surgery is considered in those that fail to respond to medical management. Surgical treatment of hiatal hernia can be performed laparoscopically. Treatment involves plication of the esophageal hiatus, as well as a pexy of the esophagus to the diaphragm and a left sided gastropexy...

Limb amputations can be devastating and significantly affect an individual's independence, leading to functional and psychosocial challenges in nearly 2 million people in the United States alone. Over the past decade, robotic devices driven by neural signals such as neuroprostheses have shown great potential to restore the lost function of limbs, allowing amputees to regain movement and sensation. However, current neuroprosthetic interfaces have challenges in both signal quality and long-term stability. To overcome these limitations and work toward creating bionic limbs, the Neuromuscular Laboratory at University of Michigan Plastic Surgery has developed the Regenerative Peripheral Nerve Interface (RPNI)...

Fracture fixation in an ageing population is challenging and fixation failure increases mortality and societal costs. We report a novel fracture fixation treatment by applying a hydroxyapatite (HA) based biomaterial at the bone-implant interface and biologically activating the biomaterial by systemic administration of a bisphosphonate (zoledronic acid, ZA). We first used an animal model of implant integration and applied a calcium sulphate (CaS)/HA biomaterial around a metallic screw in the tibia of osteoporotic rats...

Veterinary minimally invasive surgery (MIS) training options are becoming more available. This article reviews new developments in this area and the current evidence for manual skills and cognitive training of MIS.

Innovative bioengineering strategies utilizing extracellular matrix (ECM) based scaffolds derived from decellularized tissue offer new prospects for restoring damaged uterine tissue. Despite successful fertility restoration in small animal models, the translation to larger and more clinically relevant models have not yet been assessed. Thus, our study investigated the feasibility to use a 6 cm2 graft constructed from decellularized sheep uterine tissue, mimicking a future application to repair a uterine defect in women...

This article reviews minimally invasive approaches to the nasopharynx. It also introduces a novel approach, transbuccal retrograde rigid pharyngoscopy, and describes three cases in which this approach was used.

BACKGROUND: The tumor immune microenvironment is distinct between early-onset and late-onset colorectal cancer which facilitates tumor progression. We previously identified several genes, including complement factor D, as having increased expression in patients with early-onset colorectal cancer. OBJECTIVE: This study aimed to assess and validate differential expression of immune genes in early and late-onset colorectal cancer. We also aimed to test known drugs targeting genes increased in early-onset colorectal cancer in preclinical mouse models...

Pulmonary hypertension (PH) associated with left heart disease (PH-LHD) is the most common form of PH. In PH-LHD, changes in the pulmonary vasculature are assumed to be mainly caused by pulmonary venous congestion. However, the underlying mechanisms of this form of PH are poorly understood. We aimed to establish a model of PH associated with pulmonary venous congestion. Wistar-Kyoto rats underwent partial occlusion of the left pulmonary vein to induce pulmonary venous congestion or sham surgery and were assessed at various time points post-surgery (3, 6, 9, 12 weeks)...

Monitoring homeostasis is an essential aspect of obtaining pathophysiological insights for treating patients. Accurate, timely assessments of homeostatic dysregulation in deep tissues typically require expensive imaging techniques or invasive biopsies. We introduce a bioresorbable shape-adaptive materials structure that enables real-time monitoring of deep-tissue homeostasis using conventional ultrasound instruments. Collections of small bioresorbable metal disks distributed within thin, pH-responsive hydrogels, deployed by surgical implantation or syringe injection, allow ultrasound-based measurements of spatiotemporal changes in pH for early assessments of anastomotic leaks after gastrointestinal surgeries, and their bioresorption after a recovery period eliminates the need for surgical extraction...

Hypertension is a leading cause of cerebral small vessel disease (CSVD) and vascular dementia in elderly individuals. We aimed to assess cerebral perfusion and dynamic changes in brain structure in stroke-prone renovascular hypertensive rats (RHRSPs) with different durations of hypertension and to investigate whether they have pathophysiological features similar to those of humans with CSVD. The RHRSP model was established using the two-kidney, two-clip (2k2c) method, and the Morris water maze (MWM) test, MRI, immunohistochemistry, and biochemical analysis were performed at multiple time points for up to six months following the 2k2c operation...

Small joint reconstruction remains challenging and can lead to prosthesis-related complications, mainly due to the suboptimal performance of the silicone materials used and adverse host reactions. In this study, we developed hybrid artificial joints using three-dimensional printing (3D printing) for polycaprolactone (PCL) and incorporated electrospun nanofibers loaded with drugs and biomolecules for small joint reconstruction. We evaluated the mechanical properties of the degradable joints and the drug discharge patterns of the nanofibers...

A 10-month-old female neutered domestic shorthair cat presented with a history of urinary incontinence and recurrent bacterial cystitis since 2 months of age. Physical examination was unremarkable other than vulval hypoplasia. Genitourinary dysplasia was diagnosed following a physical examination, CT imaging and retrograde positive contrast urethrocystography. Attempted medical management of the urinary incontinence was unsuccessful. Surgical treatment consisted of cystourethroplasty combined with artificial urethral sphincter placement, resulting in marked improvement of urinary continence...