Ex-vivo articular cartilage removal from equine proximal interphalangeal joints using cannulated drill bits.

Objective: This report evaluates the use of 4.5- and 5.5-mm cannulated drill bits for articular cartilage removal from the proximal interphalangeal joints of equine cadaver limbs. Animals: Limbs from 8 equine cadavers, all with normal proximal interphalangeal joints. Procedure: Proximal interphalangeal joints of 32 limbs from 8 equine cadavers were drilled using either 4.5- or 5.5-mm cannulated drill bits. Pastern joints were then disarticulated, and intra-articular drilling was evaluated by visual inspection. Results: Post-drilling evaluation revealed complete intra-articular drilling occurred in all 32 joints. Conclusion: Canulated 4.5- and 5.5-mm drill bits resulted in consistent accurate intra-articular drilling in the proximal interphalangeal joint of horses. Clinical relevance: Cannulated drill bits provided an effective and consistent modality for articular cartilage removal with potential for improved accuracy of articular drilling and applications in minimally invasive proximal interphalangeal joint arthrodesis.

Objectif: Ce rapport évalue l'utilisation de forets canulés de 4,5 et 5,5 mm pour l'élimination du cartilage articulaire des articulations interphalangiennes proximales des membres de cadavres équins. Animaux: Membres provenant de huit cadavres équins, tous avec des articulations interphalangiennes proximales normales. Procédure: Les articulations interphalangiennes proximales de 32 membres de huit cadavres équins ont été percées à l'aide de forets canulées de 4,5 ou 5,5 mm. Les articulations du paturon ont ensuite été désarticulées et le forage intraarticulaire a été évalué par inspection visuelle. Résultats: L'évaluation post-forage a révélé qu'un forage intra-articulaire complet s'était produit dans les 32 articulations. Conclusion: Les forets canulés de 4,5 et 5,5 mm ont permis un forage intra-articulaire précis et constant dans l'articulation interphalangienne proximale des chevaux. Pertinence clinique: Les forets canulés ont fourni une modalité efficace et constante pour l'élimination du cartilage articulaire avec un potentiel d'amélioration de la précision du forage articulaire et des applications dans l'arthrodèse de l'articulation interphalangienne proximale de manière minimalement invasive.(Traduit par Dr Serge Messier).

Ability to Perform Laparoscopic Intra- and Extracorporeal Suture Ligations in a Live Canine Ovariectomy Model after Simulation Training.

Veterinary resident training in minimally invasive surgery is currently inconsistent and depends on innate psychomotor skills. Simulation training has been shown to effectively increase basic skills, but demonstration of simulation training effects on advanced skills in the operating room is sparse. We aimed to determine if simulation-trained novice surgeons were able to perform laparoscopic suture ligation in live dogs. Three novice laparoscopic surgeons underwent a 12-session simulation training program with subsequent laparoscopic skills testing to demonstrate competency. The median skills scores of trainees and of one experienced surgeon were 417 and 472, respectively. Eighteen healthy client-owned (shelter) dogs were operated on by four surgeons: one experienced American College of Veterinary Surgeons (ACVS) diplomate, two novice ACVS residents, and one novice ACVS diplomate. Laparoscopic ovariectomy was performed with suture ligation of the ovarian pedicles. Successful surgery was defined as no evidence of ovarian vessel bleeding after transection of the pedicles. Simulation-trained novices performed successful suture-ligated ovariectomies in 11/13 dogs (85%), and the experienced surgeon in 5/5 (100%) dogs. Median total ligation time was 30 minutes (range: 17-57), which was not different among surgeons (p = .118). Median total surgery time was 105 minutes (range: 69-156) for novices and 89 minutes (range: 65-99) for the experienced surgeon (p = .038). Extensive simulation training including suturing may contribute toward surgery residents being able to perform complex laparoscopic procedures. These results need to be confirmed in larger numbers of trainees.

Ex vivo radiocontrast description of the caudal epigastric arteries in horses.

OBJECTIVE: To determine the location of the deep and superficial caudal epigastric arteries in relation to 3 midline positions and the relationship between the location of these arteries, body circumference, and body condition score. STUDY DESIGN: Descriptive anatomical study. SAMPLE POPULATION: Nine horses, aged 1-28 years (mean 10.61 ± 8.89 SD). METHODS: Body condition score and body circumference were measured prior to euthanasia. Angiographic studies of the deep and superficial caudal epigastric arteries were performed on resected abdominal walls. The distances between the deep and the superficial caudal epigastric arteries and 3 midline positions were measured. Correlations among these distances, body circumference, and body condition score were analyzed. RESULTS: The location of the deep caudal epigastric artery correlated with body circumference and body condition score at the umbilicus (r = 0.53 and 0.68, respectively), midpoint landmark (r = 0.79 and 0.83, respectively), and prepubic tendon attachment (r = 0.69 and 0.78, respectively). The course of this artery could be estimated by multiplying body circumference by 0.04 ± 0.02 at the umbilicus, 0.07 ± 0.01 at the midpoint landmark, and 0.03 ± 0.015 at the prepubic tendon attachment. The course of the superficial caudal epigastric artery did not correlate with anatomic landmarks. CONCLUSION: The course of the deep caudal epigastric artery could be estimated at 3 midline landmarks on the basis of body circumference and body condition score in equine cadavers. CLINICAL SIGNIFICANCE: Predicting the course of the caudal epigastric arteries in the equine abdomen based on correlation among location, body circumference, and body condition score may prevent iatrogenic damage during creation of laparoscopic portals.

Comparison of incisional bursting strength of 2-strand continuous crossing and simple continuous patterns for closure of the equine linea alba.

The objective of this study was to assess and compare the bursting pressure and mode of failure of a 2-strand continuous crossing suture pattern and a simple continuous suture pattern for closure of the equine linea alba. No difference in bursting strength or mode of failure was found between the 2 suture patterns.

Comparaison de la force d'éclatement des incisions des sutures simples continues et des sutures croisées continues à deux fils pour la fermeture de la linea alba des équidés. Cette étude avait pour objectif d'évaluer et de comparer la pression d'éclatement et le mode d'échec d'un type de suture croisée continue à deux fils et d'un type de suture simple continue pour la fermeture de la linea alba des équidés. Aucune différence de force d'éclatement ou de mode d'échec n'a été constatée entre les deux types de suture.(Traduit par Isabelle Vallières).

Laparoscopic evaluation of the small intestine in the standing horse: Technique and effects.

OBJECTIVE: To evaluate the feasibility and clinical outcomes after laparoscopic evaluation of the small intestines via laparoscopy. STUDY DESIGN: Prospective pilot study. ANIMALS: Healthy adult horses (n = 5). METHODS: Horses were restrained in standing stocks and received an infusion of detomidine. One port was placed in the left last intercostal space and 3 ports were placed in the right paralumbar fossa. The small intestine was run with atraumatic laparoscopic grasping forceps, from the duodenocolic plica to the ileocecal plica. Postoperative pain was scored every 4 hours for the first 48 hours. Horses were monitored via physical examinations for 2 weeks. Second look laparoscopy was repeated at 2 weeks, to run the small intestine and assess iatrogenic changes. An exploratory celiotomy was performed in 2 horses, 2 months later and long-term follow-up was recorded in 3 horses. RESULTS: Laparoscopic evaluation of the entire small intestine was successfully completed twice in every horse. This evaluation lasted 39 ± 21.2 minutes (mean ± SD), while total surgery time was 73 ± 34.1 minutes. Postoperative physical examinations remained normal in all horses, and pain scores were scored as mild. The only abnormalities at second look laparoscopy consisted of multifocal petechiae and ecchymoses in all horses, resolved by 2 months in the 2 horses explored via celiotomy. Three horses with long-term follow-up were healthy 8 months after the study. CONCLUSION: Running the small intestine laparoscopically is a feasible procedure in standing normal horses, and does not cause significant discomfort nor complications.

Comparison of 2 training programs for basic laparoscopic skills and simulated surgery performance in veterinary students.

OBJECTIVE: To compare the effects of 2 training curricula on laparoscopic skills and performance of simulated surgery in veterinary students. STUDY DESIGN: Prospective study. SAMPLE POPULATION: Veterinary students (n = 33) with no prior hands-on experience in minimally invasive surgery. METHODS: Basic laparoscopic skills (BLS) were assessed based on 5 modified McGill inanimate system for training and evaluation of laparoscopic skills. Motion metrics and an objective structured assessment of technical skills (OSATS) were used to evaluate surgical skills during a simulated laparoscopic cholecystectomy performed in an augmented reality simulator. Students were randomly assigned to either skill-based (group A) or procedural-based (group B) training curriculum. Both tests were performed prior to and after a 10-session training curriculum. RESULTS: Post-training BLS results were improved in both training groups (P < .001). Seven participants completed both presimulated and postsimulated laparoscopic cholecystectomy, preventing paired analysis. Based on motion metrics analysis, participants completed tasks in a shorter time (P = .0187), and with better economy of movement (P = .0457) after training. No difference was detected in OSATS before and after training. CONCLUSION: Both training curricula improved BLS, but significant differences were not detected between the procedural-based training program and basic skills training alone in veterinary students. Motion metrics such as time, economy of movement, and instrument path were superior to an OSATS, when assessing surgical performance. Further studies are needed to compare the effects of different simulators on the training of veterinarians with diverse laparoscopic surgical experience.

Morcellation for testes extraction in horses undergoing standing laparoscopic cryptorchidectomy.

The major objective of this study was to describe the use of morcellation for standing laparoscopic cryptorchidectomy in 30 client-owned horses. A second objective was to describe a laparoscopic-assisted standing scrotal technique for removal of a descended testis in unilateral cryptorchids. Morcellation for extraction of abdominal testes is effective, efficient, and well-tolerated. Morcellation enabled safe and straightforward extraction of testes from the abdomen through an approximately 13- to 20-mm incision using a 2-portal technique. No incisional or morcellator-related complications occurred. Our laparoscopic-assisted standing scrotal technique for removal of a descended testis in unilateral cryptorchids entails intra-abdominal sealing and transection of the spermatic cord under laparoscopic viewing and subsequent removal of the testis through a scrotal incision. This technique enabled the surgeon to confirm hemostasis after transection of the spermatic cord and allowed tension-free removal of the descended testis. No intra-operative or incisional complications were encountered.

Morcellement pour l'extraction des testicules chez les chevaux subissant une cryptorchidectomie laparascopique debout. L'objectif majeur de cette étude consistait à décrire l'utilisation du morcellement pour la cryptorchidectomie laparascopique debout chez 30 chevaux appartenant à des clients. Un second objectif était de décrire une technique scrotale debout assistée par laparascopie pour l'enlèvement d'un testicule descendu pour les cryptorchides unilatéraux. Le morcellement pour l'extraction des testicules abdominaux est efficace et bien tolérée. Le morcellement a permis une extraction sûre et simple des testicules par l'abdomen par une incision d'environ 13 à 20 mm à l'aide d'une technique à deux portails. Aucune complication cicatricielle ou liée au morcellateur ne s'est produite. Notre technique scrotale debout assistée par laparoscopie pour l'enlèvement des testicules descendus dans les cryptorchides unilatéraux implique un scellement intra-abdominal et le sectionnement transversal du cordon spermatique sous une vue laparascopique et l'enlèvement subséquent des testicules par une incision scrotale. Cette technique a permis au chirurgien de confirmer l'hémostase après le sectionnement transversal du cordon spermatique et a permis l'enlèvement sans tension des testicules descendus. Aucune complication intra-opératoire ou cicatricielle ne s'est produite.(Traduit par Isabelle Vallières).

Instrument Motion Metrics for Laparoscopic Skills Assessment in Virtual Reality and Augmented Reality.

OBJECTIVE: To determine the construct and concurrent validity of instrument motion metrics for laparoscopic skills assessment in virtual reality and augmented reality simulators. STUDY DESIGN: Evaluation study. SAMPLE POPULATION: Veterinarian students (novice, n = 14) and veterinarians (experienced, n = 11) with no or variable laparoscopic experience. METHODS: Participants' minimally invasive surgery (MIS) experience was determined by hospital records of MIS procedures performed in the Teaching Hospital. Basic laparoscopic skills were assessed by 5 tasks using a physical box trainer. Each participant completed 2 tasks for assessments in each type of simulator (virtual reality: bowel handling and cutting; augmented reality: object positioning and a pericardial window model). Motion metrics such as instrument path length, angle or drift, and economy of motion of each simulator were recorded. RESULTS: None of the motion metrics in a virtual reality simulator showed correlation with experience, or to the basic laparoscopic skills score. All metrics in augmented reality were significantly correlated with experience (time, instrument path, and economy of movement), except for the hand dominance metric. The basic laparoscopic skills score was correlated to all performance metrics in augmented reality. The augmented reality motion metrics differed between American College of Veterinary Surgeons diplomates and residents, whereas basic laparoscopic skills score and virtual reality metrics did not. CONCLUSION: Our results provide construct validity and concurrent validity for motion analysis metrics for an augmented reality system, whereas a virtual reality system was validated only for the time score.

Transoral snare removal of subepiglottic cysts.

OBJECTIVE: The objective of this demonstration was to describe and simulate a surgical technique for removing subepiglottic cysts in horses via an oral approach under endoscopic guidance using a cadaver model for simulation and clinical data. The technique aims to provide a minimally invasive method for the removal of these cysts. ANIMALS: 2 clinical case images from the Washington State University Teaching Hospital were used in the video. In a third horse euthanized for reasons unrelated to the study, the procedure was simulated after the head was frozen and transected transversally. METHODS: Files from 2 horses were reviewed, and the relevant parts were selected. The horse head was set on a stand, and a simulated cyst was implanted under the mucosa, made of the fingertip from a glove filled with carboxymethyl cellulose gel, and sutured. The procedure was performed by one of the authors (CAR) and recorded. A bronchoesophageal grasping forceps and cautery snare were used to simulate a clinical situation in dorsal recumbency. RESULTS: The cyst was successfully removed as in the real procedure, and the demonstration was recorded for educational use. The review of the videos shows that the simulated procedure is also achievable in a real clinical environment. CLINICAL RELEVANCE: This technique provides a minimally invasive method for the removal of subepiglottic cysts in horses. The demonstration of this procedure is crucial for the training of surgeons, as it allows the visualization of the procedure in a controlled setting, free from the complications of real clinical situations.

Comparison of thoracic and abdominal cavity volumes during abdominal CO2 insufflation and abdominal wall lift.

OBJECTIVE: To compare thoracic and abdominal cavity volumes during abdominal CO2 insufflation and abdominal wall lift (AWL) conditions. STUDY DESIGN: In vitro cadaveric study. ANIMALS: Mature medium-to-large breed fresh canine cadavers (n = 6). METHODS: Each cadaver was imaged with computed tomography (CT) under baseline, abdominal CO2 insufflation, and AWL conditions. Measurements of thoracic and abdominal cavities were performed for each condition using image-analyzing software. Resulting volumes for each cadaver were converted to percent change from baseline to normalize the data. The t-tests were used to compare percent changes of both thoracic and abdominal volumes. RESULTS: Thoracic volume significantly decreased from baseline during CO2 insufflation (P < .01). No significant difference in thoracic volume occurred with AWL when compared with baseline. Abdominal volume increased by 80% with CO2 insufflation (95% CI: 56.4-107.0%) but only 25% with AWL (95% CI: 12.3-37.8%). CONCLUSIONS: Abdominal CO2 insufflation results in decreased thoracic volume when compared with baseline. AWL preserved thoracic volume similar to baseline. Abdominal volumes achieved with abdominal CO2 insufflation are significantly greater than those attained with AWL.

Midbody penile urethrocutaneous fistula repaired by fistulectomy and urethral anastomosis in a stallion.

CASE DESCRIPTION: A 12-year-old Friesian stallion was examined because of a 1-year history of preputial injury and urination through a urethrocutaneous fistula located at the midbody of the ventral aspect of the penis. CLINICAL FINDINGS: Physical examination revealed an opening with a clearly apparent mucocutaneous junction 12 cm from the distal opening of the urethra on the ventral left side of the penis. Endoscopic examination of the distal portion of the urethra confirmed a blind pouch with no communication with the fistula or proximal portion of the urethra. TREATMENT AND OUTCOME: A temporary perineal urethrostomy was performed with sedation and local anesthesia, with the stallion standing, to divert urine from the urethral reconstruction site. Fistulectomy and urethral resection and anastomosis were performed under general anesthesia with the stallion in dorsal recumbency. At 15 days after surgery, endoscopic examination of the urethra revealed distortion of the urethral lumen at the fistulectomy site. Under sedation, the urethra was dilated for 5 minutes every 12 hours for 3 days. At 22 days after surgery, endoscopic examination of the urethra revealed a healed anastomosis site and a large urethral luminal diameter. At 36 months after surgery, the owner reported that the stallion had normal micturition and had sired multiple foals by live cover matings. CLINICAL RELEVANCE: Severe preputial or penile trauma in horses is most commonly treated with amputation because of concerns of postoperative urethral stricture and occlusion. To the authors' knowledge, this case represented the first time that a successful end-to-end anastomosis of the distal portion of the urethra has been performed in a stallion.

Effects of head position on internal and external carotid pressures in standing sedated horses.

The effects of head position on internal carotid artery (ICA) and external carotid artery (ECA) pressures in standing sedated horses were evaluated in this study. The common carotid artery (CCA) was catheterized in 6 horses using an ultrasound-guided technique to facilitate placement of a pressure transducer within the ICA and ECA at the level of the guttural pouch. Transducer position was confirmed by endoscopic visualization. Mean arterial pressure (MAP) was measured with horses in both a head-up and head-down position. The dorsal metatarsal artery was catheterized as a control. Maintaining a head-up position decreased MAP in both the ICA (median: 75.21 mmHg) and ECA (median: 79.43 mmHg), relative to the head-down position (ICA median: 104.65 mmHg; ECA median: 102.26 mmHg). Mean arterial pressure in the dorsal metatarsal artery was not affected by head position. The head-up position resulted in lower arterial pressures in both the ICA and ECA (P = 0.03) compared with the head-down position in standing sedated horses.

Cette étude a évalué les effets de la position de la tête sur la pression artérielle au niveau de l'artère carotide interne (ICA) et de l'artère carotide externe (ECA) chez des chevaux sous sedation debout. L'artère carotide commune (CCA) a été cathétérisée chez six chevaux en utilisant une technique échoguidée pour faciliter le placement d'un transducteur de pression dans l'ICA et l'ECA au niveau de la poche gutturale. La position du transducteur a été confirmée par endoscopie. La pression artérielle moyenne (MAP) a été mesurée chez les chevaux avec la tête en position haute et en position basse. L'artère métatarsienne dorsale a été cathétérisée et a servi comme témoin. Les MAP enregistrées au niveau de l'ICA (médiane: 75,21 mmHg) et de l'ECA (médiane: 79,43 mmHg) lorsque la tête est en position élevée sont plus faibles que celles enregistrées lorsque la tête est en position basse (médiane ICA: 104,65 mmHg; médiane ECA: 102,26 mmHg). La MAP de l'artère métatarsienne dorsale n'a pas été affectée par la position de la tête. En conclusion, chez les chevaux sédatés et debout, la position élevée de la tête produit des pressions artérielles plus faibles au niveau de ICA et ECA (P = 0,03) que celles obtenues lorsque la tête est en position basse.(Traduit par les auteurs).

Treatment of temporohyoid osteoarthropathy in horses with a basihyoid-ceratohyoid disarticulation technique: 6 cases (2018-2019).

OBJECTIVE: To describe a technique for basihyoid-ceratohyoid disarticulation (BCD) in standing sedated horses affected by temporohyoid osteoarthropathy (THO) and report outcomes for horses that underwent the procedure. ANIMALS: 6 client-owned horses. PROCEDURES: Electronic medical records of a veterinary teaching hospital were searched to identify horses that underwent BCD for treatment of THO from 2018 to 2019. Signalment, clinical data, use of the horse, and complications were recorded. Follow-up data obtained by telephone interview with owners included the clinical outcome and time to improvement after surgery, any persistent clinical signs, horse's activity level before onset of clinical signs and after BCD, subsequent use of the horse, and whether they would pursue the same treatment again. RESULTS: All horses tolerated the procedure well, with no complications and improved neurologic function after BCD. Five of 6 horses had a reported activity level equal to or greater than that prior to having signs of THO. Three of 3 horses with acute ataxia prior to BCD reportedly had full resolution of this sign; 3 of 4 horses with facial nerve deficits prior to BCD had mild residual facial nerve deficits at follow-up. All owners indicated they would pursue BCD again. CONCLUSIONS AND CLINICAL RELEVANCE: The BCD procedure was performed safely in this sample of THO-affected horses that were sedated while standing, avoiding risks associated with general anesthesia and resulting in no adverse effects such as iatrogenic injury to neurovascular structures.

Assessment of laparoscopic skills before and after simulation training with a canine abdominal model.

OBJECTIVE-To determine whether scores for basic laparoscopic skills were significantly associated with extent of laparoscopic experience and compare basic laparoscopic skill scores obtained before and after 2 laparoscopic training sessions incorporating a canine abdominal model. DESIGN-Evaluation study. SAMPLE POPULATION-8 experienced and 25 novice individuals. PROCEDURES-Novice participants were randomly assigned to control (n = 10) and training (15) groups. Individuals in the experienced and novice training groups were required to undergo 2 training sessions with a canine abdominal model. Basic laparoscopic skills were assessed twice on the basis of 3 tasks included in the McGill Inanimate Simulator for Training and Evaluation of Laparoscopic Skills (MISTELS). RESULTS-For the novice training group, laparoscopic skills scores were significantly higher after training than before, but for individuals in the novice control group, scores did not differ significantly between the first and second assessments. The increase in score for the novice training group was significantly higher than increases for the experienced group and for the novice control group, but the increase in score for the experienced group was not significantly different from the increase in score for the novice control group. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that basic laparoscopic skills scores obtained with the MISTELS were associated with extent of laparoscopic experience and that training with a canine abdominal model could increase skills scores for individuals without previous laparoscopic experience.

A laparoscopic surgical skills assessment tool for veterinarians.

Our aim in this study was to validate a test of laparoscopic surgical performance by determining the relation of scores from an objective structured assessment of technical skills performed in a canine abdominal model to experience and basic laparoscopic skills. The number of years the participants had performed rigid video-endoscopic procedures (VEP), using triangulation skills, correlated positively with both evaluators' total surgical performance scores for all three evaluation methods: global rating scale, visual analog scale (VAS) rating of overall performance, and operative component rating scale (OCRS). Experience of VEP without triangulation skills (i.e., flexible endoscopy, otoscopy) or video game experience did not correlate with surgical performance. A highly validated basic laparoscopic skills assessment (McGill University inanimate system for training and evaluation of laparoscopic skills, or MISTELS) score was strongly correlated with the VAS score for surgical performance and OCRS scores. Inter-rater reliability was high for the VAS and OCRS evaluation methods, and scores from the detailed OCRS method did not differ between evaluators. In conclusion, the surgical performance test correlated with VEP triangulation experience and basic laparoscopic skills. This type of test needs to be evaluated in a larger sample population including higher numbers of veterinary laparoscopic surgeons for further validation.

The Use of Pneumatic Impact Lithotripsy in a Laparoscopic Retrieval Pouch for Removal of Large Cystoliths in Two Female Horses.

Two mares, aged 15 and 21 years, were examined because of urinary incontinence, intermittent hematuria, and urine scalding. On admission of both horses, physical parameters were within normal limits and urine scalding of the skin at the ventral perineum was noted. Transrectal palpation and cystoscopy revealed a large type I cystolith (>10 cm) with associated hyperemia and focal ulceration of the bladder mucosa. In horse 1, hemogram, serum biochemical analysis, and renal ultrasound were not performed because of owner finances. In horse 2, results from hematological and serum biochemical analysis were unremarkable and renal ultrasonography did not reveal any abnormalities. Pneumatic impact lithotripsy in a laparoscopic retrieval pouch was performed under cystoscopic guidance after caudal epidural anesthesia, with the horses standing and under sedation. A laparoscopic retrieval device was passed alongside a flexible endoscope into the urinary bladder and the cystolith was manipulated into the pouch. A customized single stainless-steel rod scaler attached to an air compressor was used for fragmentation of the cystolith contained within the retrieval pouch. Lithotripsy time was 42 minutes for horse 1 and 31 minutes for horse 2. Both horses were released from hospital the day of surgery. Both horses were continent and voided normal streams of urine for the duration of the follow-up periods of 27 and 19 months for horse 1 and horse 2, respectively. Pneumatic impact lithotripsy in a laparoscopic retrieval pouch provided a time-efficient and minimally invasive surgical treatment option for removal of large cystoliths in mares.

A porcine ligated loop model reveals new insight into the host immune response against Campylobacter jejuni.

The symptoms of infectious diarrheal disease are mediated by a combination of a pathogen's virulence factors and the host immune system. Campylobacter jejuni is the leading bacterial cause of diarrhea worldwide due to its near-ubiquitous zoonotic association with poultry. One of the outstanding questions is to what extent the bacteria are responsible for the diarrheal symptoms via intestinal cell necrosis versus immune cell initiated tissue damage. To determine the stepwise process of inflammation that leads to diarrhea, we used a piglet ligated intestinal loop model to study the intestinal response to C. jejuni. Pigs were chosen due to the anatomical similarity between the porcine and the human intestine. We found that the abundance of neutrophil related proteins increased in the intestinal lumen during C. jejuni infection, including proteins related to neutrophil migration (neutrophil elastase and MMP9), actin reorganization (Arp2/3), and antimicrobial proteins (lipocalin-2, myeloperoxidase, S100A8, and S100A9). The appearance of neutrophil proteins also corresponded with increases of the inflammatory cytokines IL-8 and TNF-α. Compared to infection with the C. jejuni wild-type strain, infection with the noninvasive C. jejuni ∆ciaD mutant resulted in a blunted inflammatory response, with less inflammatory cytokines and neutrophil markers. These findings indicate that intestinal inflammation is driven by C. jejuni virulence and that neutrophils are the predominant cell type responding to C. jejuni infection. We propose that this model can be used as a platform to study the early immune events during infection with intestinal pathogens.

Pneumocephalus secondary to removal of an osteoma from the paranasal sinuses of a horse.

CASE DESCRIPTION: A 2-year-old Quarter Horse was evaluated because of a progressive left-sided facial deformity and unilateral nasal and ocular discharge. CLINICAL FINDINGS: Physical examination revealed convexity of the left frontonasal region, left-sided nasal and ocular discharge, and decreased air flow through the left nares. Radiography and computed tomography revealed an extensively mineralized mass occupying most of the left paranasal sinuses. TREATMENT AND OUTCOME: The mass was surgically debulked, but complete removal was precluded because the mass was tightly adhered to the frontal and maxillary bones. Results of histologic examination of the mass were consistent with a diagnosis of osteoma. The horse developed transient pyrexia and colic following surgery, and postoperative radiography revealed gas opacities in the lateral ventricles of the brain, consistent with iatrogenic pneumocephalus. However, the horse did not develop any neurologic signs and was performing normally 2 years after surgery. CLINICAL RELEVANCE: Findings reinforce concerns that paranasal sinus surgery in horses can be associated with intracranial complications such as pneumocephalus. In horses with a mass involving the paranasal sinuses, computed tomography may be helpful in determining the boundaries of the mass and formulating a surgical treatment plan.

Hemodynamic changes during laparoscopic radiofrequency ablation of normal adrenal tissue in dogs.

OBJECTIVE: To determine the hemodynamic response to radiofrequency ablation (RFA) of normal adrenal tissue in dogs. STUDY DESIGN: Experimental study. ANIMALS: Healthy adult mixed-breed dogs (n=6). METHODS: During general anesthesia a Swan-Ganz thermodilution catheter was flow directed into the pulmonary artery and used to quantify cardiac output. An arterial catheter was used for direct blood pressure measurements. An RFA device was introduced into the left adrenal gland under observation through laparoscopic instrumentation. Blood samples were collected and hemodynamic variables studied after a stable surgical anesthetic depth was achieved (time 1), during CO(2) insufflation of the abdomen (time 2), during adrenal RFA (time 3), and after completed RFA (time 4). Catecholamine determinations were performed with a human enzyme immunoassay. Histopathology was performed to verify medullary necrosis. RESULTS: Arterial, pulmonary arterial and central venous pressure, and plasma norepinephrine increased more during RFA than during abdominal insufflation. Heart rate and cardiac index did not differ between time points. High baseline epinephrine was present and significant differences between time points were not detected. Systemic vascular resistance had very high individual variation and differences were not detected. CONCLUSIONS: RFA of normal adrenal tissues is associated with severe hemodynamic alterations. Further studies of the optimal blockage of catecholamine-induced hypertension in dogs are warranted. CLINICAL RELEVANCE: Clinicians should prepare for potential hypertensive crisis during RFA of adrenal masses, especially if treating a margin of normal tissue.

Use of non-contrast-enhanced computed tomography to identify deep digital flexor tendinopathy in horses with lameness: 28 cases (2014-2016).

OBJECTIVE: To describe the use of non-contrast-enhanced CT to identify deep digital flexor (DDF) tendinopathy in horses with lameness attributed to pain in regions distal to the metatarsophalangeal or metacarpophalangeal joints. DESIGN: Retrospective case series. ANIMALS: 28 client-owned horses. PROCEDURES: Medical records were searched to identify horses that underwent non-contrast-enhanced CT with or without high-field MRI as part of an evaluation for lameness localized to areas distal to the metacarpophalangeal or metatarsophalangeal joint in ≥ 1 limb. Horses were included in the study if they had ≥ 1 DDF tendon lesion (DDF tendinopathy) identified. Signalment, lameness examination findings and response to perineural anesthesia, imaging modality, anesthetic agents and duration of anesthesia, and imaging findings were recorded. Data were summarized descriptively. RESULTS: Bilateral imaging was performed for all horses, irrespective of unilateral or bilateral lameness. Nine of 28 horses underwent both CT and MRI, and all DDF tendon lesions identified by one modality were identified by the other. Of 48 limbs with DDF tendinopathy, 46 (96%) had core lesions and 35 (73%) had dorsal border irregularities. Median anesthesia time for CT and CT followed by MRI was 15 and 110 minutes, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that non-contrast-enhanced CT was useful for identifying DDF tendinopathy in horses with lameness localized to the phalangeal regions, and this was supported by consistency of findings in a subset of horses that underwent MRI. Further research is needed to confirm these results.