Long-term outcomes of 54 dogs with tracheal collapse treated with a continuous extraluminal tracheal prosthesis.

OBJECTIVE: To describe the surgical placement of a continuous extraluminal tracheal prosthesis (CETP) and report the subsequent postoperative clinical outcomes in dogs with tracheal collapse. STUDY DESIGN: Retrospective case series. ANIMALS: Fifty-four dogs. METHODS: Medical records of dogs in which cervical and/or thoracic inlet tracheal collapse was diagnosed and treated by placement of a CETP between 2010 and 2017 were reviewed to evaluate postoperative complications, changes in respiratory function, and survival. Histological examinations of tracheal tissues performed in 2 dogs at 51 and 57 months after surgery were also reviewed. RESULTS: Fifty-three (98%) dogs survived to discharge. Postoperative complications included laryngeal paralysis (1 dog), disseminated intravascular coagulation (1 dog), and recurrent tracheal collapse (2 dogs). None of the dogs exhibited clinical evidence of tracheal necrosis. Preoperative dry, harsh cough resolved in 87% of the dogs after surgery. Goose honking cough was resolved in 25 of 26 (96%) dogs. Median follow-up time was 30 months (range, 16 days to 76 months). The survival rate at 36 months was 86% (CI: 75%-96%). On histological examination in 2 dogs, the tracheal tissue surrounding the prosthesis was well preserved and without evidence of chronic inflammation. CONCLUSION: Continuous extraluminal tracheal prosthesis placement in dogs with tracheal collapse resulted in low postoperative complication rates and good long-term outcomes. CLINICAL SIGNIFICANCE: Continuous extraluminal tracheal prosthesis placement provides a viable alternative surgical option for managing dogs with tracheal collapse.

Outcomes of horses treated with removal of a laryngoplasty prosthesis.

OBJECTIVE: To determine the proportion of horses treated by laryngoplasty prosthesis removal (LPR) for complications associated with prosthetic laryngoplasty (LP), the reason for LPR, and the outcome of horses undergoing LPR to manage iatrogenic coughing/dysphagia. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Client-owned horses treated with LP (n = 1202) and LPR (n = 58). METHODS: Clinical case records were reviewed to determine the number of horses treated with LP and LPR by the same surgeon. Historical, clinical, endoscopic, and surgical data were extracted for those horses undergoing LPR. Long-term outcome was assessed by questionnaire. RESULTS: The proportion of horses treated with LP and subsequently treated with LPR by the same surgeon was 3.5% (42/1202). Coughing/dysphagia was the reason for LPR in 90% (52/58) of horses. Sufficient follow-up to determine outcome in horses undergoing LPR for coughing/dysphagia was available in 32 horses. Arytenoid abduction grade at the time of LPR did not influence clinical response (P = .416). Presenting clinical signs resolved after LPR in 21 of 32 (66%) horses, and 24 of 32 (75%) horses returned to exercise. CONCLUSION: Coughing/dysphagia was the most common reason for LPR. Clinical signs improved in most horses after LPR. CLINICAL SIGNIFICANCE: Laryngoplasty prosthesis removal can be a useful treatment option for horses affected with unmanageable coughing/dysphagia caused by LP.

A retrospective review of 146 active and passive fixation bradycardia lead implantations in 74 dogs undergoing pacemaker implantation in a research setting of short term duration.

BACKGROUND: Canine veterinary patients increasingly benefit from implantation of transvenous pacemakers for bradyarrhythmias. No published data exist examining procedural outcomes of pacemaker implantation performed in the preclinical laboratory. The purpose was to review short term complication, infection, dislodgement, penetration rates, plus overall morbidity following pacemaker implantation in the research setting. A retrospective review of 74 Class A purpose-bred mongrels implanted with active (n = 89) and passive fixation (n = 57) intracardiac leads for dual (n = 72) or single (n = 2) chamber pacing was performed. RESULTS: All leads were implanted successfully, meeting electrical implant criteria. Follow-ups typically occurred every 7 days (first month), then at 30 day intervals. Seroma formation was 1.4% and 10.8% at the venotomy and pulse generator site respectively. Overall infection rate was 1.4%. Overall dislodgement rate was 2.1%, (2 passive atrial leads, 1 passive ventricular lead). Overall fractures and insulation defects were zero. Two helix penetrations were noted incidentally post mortem, one at the right atrial appendage and one at the right ventricle (64 dogs, 128 leads evaluated), a 1.6% event rate. Major in-life adverse events were 5.4% (4 of 74 dogs), including 1 infection and 3 lead dislodgements. CONCLUSIONS: This review demonstrates a low complication rate with bradycardia lead implants in the short term (up to 180 days), in a high volume research setting. Lead type, implant technique, surgeon experience, healthy patient population, patient size and follow-up care play a role. This review also suggests active fixation leads in the right atrial appendage of dogs are safe and reliable.

Comparison of diode laser trans-scleral cyclophotocoagulation versus implantation of a 350-mm2 Baerveldt glaucoma drainage device for the treatment of glaucoma in dogs (a retrospective study: 2010-2016).

OBJECTIVE: To compare outcomes following trans-scleral cyclophotocoagulation (TSCP) and 350-mm2 Baerveldt implantation in the treatment of canine refractory glaucoma. DESIGN: Retrospective case study. CASE SELECTION: Client owned dogs undergoing surgical treatment of glaucoma within a veterinary referral hospital. PROCEDURES: Eighty-six glaucoma surgeries were performed on 83 eyes (69 dogs) diagnosed with primary or secondary glaucoma. Medical records were retrieved, and baseline data, surgery, medications, intraocular pressures (IOPs), vision, and complications were extracted. RESULTS: Fifty-four eyes (44 dogs) were treated with TSCP and placement of an anterior chamber suture shunt; 28 eyes (24 dogs) were implanted with a Baerveldt glaucoma drainage device (GDD); and four eyes (4 dogs) underwent GDD implantation after failure of TSCP to manage IOP. Following TSCP, IOP control (<20 mmHg) and vision retention occurred in 81.5% and 42.6%, respectively, for 16.1 ± 1.36 months. Following GDD implantation, 71.4% maintained IOP <20 mmHg and 69.6% maintained vision for 11.0 ± 0.94 months. IOP control without loss of vision was more likely following Baerveldt implantation (17/28; 60.7%) than TSCP (19/54; 35.2%) (P = 0.027). One eye had functional vision restored following GDD placement. IOP control without adjunctive medications was more likely following Baerveldt implantation (P = 0.02). CONCLUSIONS: In this study, eyes treated with Baerveldt GDD implantation were more likely to maintain IOP control and retain vision compared to eyes treated with TSCP and placement of an anterior chamber suture shunt. Lack of formal randomization, inconsistencies in surgical techniques and TSCP protocols, and potential unmeasured confounders must be considered when extrapolating from this retrospective study.

Comparison of Outcome After Use of Extra-Luminal Rings and Intra-Luminal Stents for Treatment of Tracheal Collapse in Dogs.

OBJECTIVE: To report short- and long-term complications and outcomes of dogs treated for tracheal collapse secondary to chondromalacia with extra-luminal rings (ELR) or intra-luminal stents (ILS). STUDY DESIGN: Retrospective cohort. SAMPLE POPULATION: Dogs with naturally occurring tracheal collapse (n = 103). METHODS: Medical records (2002-2012) of dogs diagnosed with tracheal collapse that had treatment with ELR (n = 73) or ILS (30) were reviewed. Demographic information, procedural information, complications, survival time, and subjective outcomes were recorded. Follow-up periods were defined as <730 days (short-term) and >730 days (long-term). RESULTS: Ninety-two percent of dogs undergoing ELR and 100% of dogs undergoing ILS survived to hospital discharge. ELR dogs were significantly younger (P = .009) and significantly fewer had main-stem bronchial collapse (P < .001). After accounting for effects of age and presence of main-stem bronchial collapse, there was no significant difference in median survival time between groups. Dogs with main-stem bronchial collapse (regardless of treatment type) had a shorter survival time than dogs without main-stem bronchial collapse. Major complications occurred in ELR (42%) and ILS dogs (43%). CONCLUSIONS: Both ELR and ILS are associated with high complication rates. Younger dogs and dogs without main-stem bronchial collapse had a longer survival time, regardless of treatment.

Long-term outcome, complications and disease progression in 23 dogs after placement of tracheal ring prostheses for treatment of extrathoracic tracheal collapse.

OBJECTIVE: To report complications, long-term outcome, and disease progression in dogs with extrathoracic tracheal collapse treated by surgical placement of commercially available extraluminal rings. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs (n = 23). METHODS: Medical records (2002-2011) of dogs treated with extraluminal rings for extrathoracic tracheal collapse were reviewed. Owner interviews, conducted at >10 months postoperatively, determined response to surgery, progression of clinical signs after surgery, and frequency of medication administration. Long-term re-evaluation (>10 months after surgery) was offered for surviving dogs, including radiographs and tracheoscopy if indicated. RESULTS: Of 23 dogs, 22 survived to discharge after surgery. Clinical signs improved in all dogs at 2 weeks after surgery and at long-term re-evaluation. Fourteen dogs (65%) required no medical management for respiratory signs after surgery. Four dogs (17%) were diagnosed with laryngeal paralysis at some point after surgery, but only 9% were diagnosed within 48 hours of the surgery. Additional rings were placed between previously placed rings in 2 dogs, and 1 dog was treated with an endoluminal stent for intrathoracic tracheal collapse. Three dogs had clinical signs consistent with progression of tracheal collapse. Based on owner questionnaire, all owners were satisfied with surgical outcome. CONCLUSIONS: Treatment of severe cervical tracheal collapse with commercially-available extraluminal ring placement leads to an overall improvement in quality of life and good long-term results, with about one-third of dogs requiring continued medical management. Most dogs do not have clinical signs consistent with disease progression after surgery.

Histopathological study of the causes for failure of intrascleral prostheses in dogs and cats.

OBJECTIVE: To characterize the histopathological causes for failure of intrascleral prosthesis placement in dogs and cats. PROCEDURES: The Comparative Ocular Pathology Laboratory of Wisconsin database was searched to find canine and feline evisceration samples that were diagnosed with neoplasia. A second population included canine and feline scleral shells that were removed after an evisceration surgery had been performed. The causes for removal were divided into: neoplasia, corneal abnormalities, and other causes. RESULTS: In dogs, 163 of 1985 evisceration samples (8.21%) contained a neoplasm, whereas 17 of 88 (19.31%) evisceration samples in cats contained a neoplasm. In dogs, severe corneal disease was diagnosed in 38 of 80 scleral shells (46.25%) and neoplasia was diagnosed in 31 of 80 scleral shells (38.75%). Malignant melanoma was the most frequently diagnosed tumor, in 14 of 31 scleral shells. In cats, eight of 12 scleral shells contained a tumor (66.7%), with feline diffuse iris melanoma being diagnosed most commonly (six of eight shells). Two of 12 feline scleral shells had severe corneal disease (16.7%). Epithelial downgrowth, lining the inner aspect of the fibrous tunic, was seen in 14 of 38 canine scleral shells and in two of two feline scleral shells with severe corneal disease. CONCLUSIONS: Severe corneal disease and neoplasia are the most common causes for intrascleral prosthesis failure in dogs, whereas neoplasia is the single most common cause for intrascleral prosthesis failure in cats.

Intra- and inter-observer reliability of combined segmental measurement techniques for predicting immediate post-deployment intraluminal tracheal stent length in dogs.

This study evaluated segmental measurement techniques for predicting immediate post-deployment intraluminal tracheal stent length in dogs with naturally occurring tracheal collapse. Radiographs of 12 client-owned dogs that underwent intraluminal tracheal stent placement were retrospectively reviewed. Tracheal lengths were divided into 1, 2, 3, or 4 equal segments. Stent lengths were predicted using the widest dorsoventral height of each segment, with and without the addition of 10%, and an accompanying foreshortening chart. Techniques were compared for intra- and inter-observer reliability, and post-deployment stent length predictability. There was good to high intra- and inter-observer reliability for all segmental measurements; median intra-class correlation coefficients were 0.98 and 0.92, respectively. Measuring 2 segments without the addition of 10% to the widths was significantly more accurate in predicting immediate post-deployment stent length in terms of percent (P = 0.03) and absolute difference (P = 0.02). Segmental measuring techniques are repeatable amongst observers and may help guide stent selection.

Fiabilité intra-observateur et inter-observateur des techniques de mesure de segments combinées pour la prédiction de la longueur d'une endoprothèse trachéale intraluminale immédiatement après le déploiement chez les chiens. Cette a étude a évalué les techniques de mesure de segments pour prédire la longueur des endoprothèses trachéales intraluminales immédiatement après le déploiement chez les chiens avec un collapse trachéal naturel. Des radiographies de 12 chiens, appartenant à des propriétaires, qui avaient subi le placement d'une endoprothèse trachéale intraluminale ont été examinées rétrospectivement. Les longueurs trachéales ont été divisées en 1, 2, 3, ou 4 segments égaux. Les longueurs d'endoprothèses ont été prédites en utilisant la hauteur dorsoventrale la plus large de chaque segment, avec et sans l'ajout de 10 % et le tableau d'effet de raccourcissement connexe. Les techniques ont été comparées pour la fiabilité intra-observateur et inter-observateur et la prédictibilité de la longueur de l'endoprothèse après le déploiement. Il y avait une fiabilité intra-observateur et inter-observateur de bonne à élevée pour toutes les mesures de segments; les coefficients moyens de corrélation entre les classes étaient de 0,98 et de 0,92, respectivement. La mesure de 2 segments sans l'ajout de 10 % aux largeurs était significativement plus exacte pour la prédiction de la longueur de l'endoprothèse immédiatement après le déploiement en termes de pourcentage (P = 0,03) et de différence absolue (P = 0,02). Les techniques de mesures de segments peuvent être répétées parmi les observateurs et peuvent aider à guider le choix de l'endoprothèse.(Traduit par Isabelle Vallières).

A rabbit model of tracheal collapse for optimal self-expanding metal stents.

Investigating the characteristics of tracheas can help the understanding of diseases related to the trachea, particularly tracheal collapse (TC) in dogs. This study aimed to compare the mechanical properties of tracheas from New Zealand White (NZW) rabbits and dogs and to introduce a method for inducing a model of TC in the normal trachea. Tracheal samples were obtained from NZW rabbit cadavers (n=5) weighing 3.62-3.92 kg and from dog cadavers (n=5) weighing 2.97-3.28 kg. Three live NZW rabbits weighing 3.5-4.0 kg were used to establish the model. The radial forces of both sample sets were measured using a digital force gauge and statistically compared. Subsequently, TC was surgically induced in three female NZW rabbits by physically weakening their tracheal cartilage under general anesthesia. Their clinical signs were monitored for 3 months, and radiographic examinations were performed monthly for 3 months. The mean radial forces of the two sample sets were comparable (P>0.05). The clinical signs, radiographic examinations, and macroscopic examinations were all comparable to those of dogs with TC. The cadaveric study between the rabbits and dogs demonstrated that the surgically induced rabbit model of TC is an excellent candidate for the experimental study of dogs with TC. This study also provides a reference of tracheal radial force values to enable selection of appropriate mesh types and wire diameters of self-expanding metal stents.

Use of nitinol stents for end-stage tracheal collapse in dogs.

OBJECTIVE: To report bronchoscopic placement of nitinol stents (Vet Stent-Trachea®) for improvement of end-stage clinical signs in dogs with tracheal collapse. STUDY DESIGN: Case series. SAMPLE POPULATION: Dogs (n = 18). METHODS: Medical records (January 1, 2004-October 31, 2008) were searched for dogs with a diagnosis of tracheal collapse; 18 dogs met inclusion criteria. Tracheal diameter was compared before and after stent deployment. Stent dimensions were compared after stent deployment and at radiographic follow-up. RESULTS: There was a significant difference in the minimum tracheal diameter when initial and post deployment tracheal diameters were compared (P = .003). Stent length was significantly shorter at follow-up when compared to post deployment measurements (P = .004). Owner assessment of outcome was available for all dogs with 11.1% mortality within 60 days. Complications were documented in 9 dogs. CONCLUSIONS: Use of a nitinol stent (Vet Stent-Trachea®) in dogs with end-stage tracheal collapse is associated with a fair to good outcome despite significant temporal stent fore shortening after bronchoscopic placement.

Biodegradable sleeves for metal implants to prevent implant-associated infection: an experimental in vivo study in sheep.

OBJECTIVE: To evaluate biocompatibility of biodegradable sleeves containing antimicrobial agents, designed for local drug delivery to prevent implant-related infection. STUDY DESIGN: Synthetic polyester sleeves (a copolymer of glycolide, caprolactone, trimethylene carbonate, lactide) were cast as thin films. The antimicrobial agents incorporated in the sleeves included gentamicin sulfate, triclosan, or a combination of these drugs. ANIMALS: Adult sheep (n = 15). METHODS: Two limited contact dynamic compression plates (LC-DCP) with or without sleeves were implanted on tibiae (bilateral) of 15 sheep. Sleeves were placed over the plates before implantation. Beneath half of the plates, 5-mm drill hole defects were made in the near cortex. Samples were harvested 4 weeks later for histology and microradiography. RESULTS: Macroscopically, no irritation of bone or adjacent tissue was seen. Small remnants of sleeves were visible on histology, and positively correlated with the presence of macrophages and foreign body cells. Thick sections showed no difference between the test samples and controls in terms of fibrous capsule formation, periosteal remodeling, and defect remodeling. Inflammatory cells, macrophages, and foreign body cells were more prominent in sections with sleeves, but were not statistically significantly different from controls. Cell numbers were within normal physiologic limits normally seen as cellular response to foreign bodies consisting of polymers. CONCLUSION: The normal healing response indicated that the biodegradable sleeves demonstrate tissue biocompatibility.

Surgical outcomes in dogs with tracheal collapse treated with a novel cross-and-hook braided endoluminal stent.

BACKGROUND: Stenting is an effective treatment option for tracheal collapse in dogs. Cross-braided tracheal stents are currently the norm in veterinary medicine, but cross-and-hook braided stents have recently been adopted in human medicine. We examined whether stents manufactured using this novel braiding technique provided additional advantages for the treatment of tracheal collapse in dogs. OBJECTIVES: To evaluate the outcomes of cross-and-hook braided stent implantation in the treatment of tracheal collapse in dogs. METHODS: The medical records of 22 client-owned dogs that underwent luminal placement of cross-and-hook braided Fauna Stents for the treatment of tracheal collapse between January 2018 and July 2021 were examined and data on canine signalment, clinical signs, diagnostic test results, surgical outcomes, and postoperative complications were retrieved and analyzed statistically. RESULTS: Twenty-six stents were surgically implanted, with 20 dogs (90.9%) receiving one stent and the remaining two (9.1%) receiving two or more stents. All dogs survived the procedure. The median survival time at a median follow-up of 990 days was 879 days. At the final follow-up examination, loss or mild improvement of cough was observed in all dogs. CONCLUSIONS: Compared with conventional lumen stents, the cross-and-hook braided Fauna Stent offered a higher survival rate and improved clinical symptoms in all patients. The results of this study suggest that the Fauna Stent may be a promising treatment option for dogs with tracheal collapse.

Comparison of short-, intermediate-, and long-term results between dogs with tracheal collapse that underwent multimodal medical management alone and those that underwent tracheal endoluminal stent placement.

OBJECTIVE: To compare short-, intermediate-, and long-term results between dogs with tracheal collapse (TC) that received multimodal medical management only and those that underwent tracheal endoluminal stent placement. ANIMALS: 159 dogs with TC that underwent medical management only (MM group; n = 84) or were surgically managed by stent placement (SM group; 75). PROCEDURES: Medical records of dogs with TC that underwent medical management only or stent placement at a referral hospital between September 1, 2009, and August 1, 2018, were reviewed. Data regarding signalment, information relevant to TC, and outcome were extracted from the records and aggregated into short-, intermediate-, and long-term follow-up periods for analysis. Descriptive data and median survival times (MSTs) were compared between the MM and SM groups. RESULTS: Clinical signs of dogs in the MM group generally improved during the short term but regressed and worsened over time. The proportion of dogs with malformation-type TC that underwent stent placement (38/43 [88%]) was significantly greater than the proportion of dogs with traditional-type TC that underwent stent placement (37/107 [35%]). The MST from TC diagnosis was 3.7 years for the MM group and 5.2 years for the SM group. For dogs with severe disease, the MST was 12 days for medically managed dogs and 1,338 days for dogs that underwent stent placement. CONCLUSIONS AND CLINICAL RELEVANCE: Multimodal medical management alleviated clinical signs for months to years in dogs with mild to moderate TC disease, but stent placement should be considered for dogs with severe disease.

Osseodensification enables bone healing chambers with improved low-density bone site primary stability: an in vivo study.

Primary implant stability is a prerequisite for successful implant osseointegration. The osseodensification technique (OD) is a non-subtractive drilling technique that preserves the bone tissue, increases osteotomy wall density, and improves the primary stability. This study aimed to investigate the hypothesis that OD, through a wider osteotomy, produces healing chambers (HCs) at the implant-bone interface without impacting low-density bone primary stability. Twenty implants (3.5 × 10 mm) with a nanohydroxyapatite (nHA) surface were inserted in the ilium of ten sheep. Implant beds were prepared as follows: (i) 2.7-mm-wide using subtractive conventional drilling (SCD) technique (n = 10); (ii) 3.8-mm-wide using an OD bur system (n = 10). The sheep were randomized to two groups, with samples collected at either 14-(n = 5) or 28-days (n = 5) post-surgery and processed for histological and histomorphometric evaluation of bone-implant contact (BIC) and bone area fraction occupancy (BAFO). No significant group differences were found with respect to final insertion torque and implant stability quotient (p > 0.050). BIC values were higher for SCD after 14 and 28 days (p < 0.050); however, BAFO values were similar (p > 0.050). It was possible to conclude that the OD technique allowed a wider implant bed preparation without prejudice on primary stability and bone remodeling.

Evaluation of the susceptibility artifacts and tissue injury caused by implanted microchips in dogs on 1.5 T magnetic resonance imaging.

Performing magnetic resonance imaging (MRI) in patients with a metallic implant raises concern over the potential complications, including susceptibility artifacts, implant migration, and heat injury. The purpose of this study was to investigate these complications in dogs with implanted microchips by evaluating MR images and the histopathological changes after 1.5 Tesla (T) MRI. Five dogs underwent microchip implantation in the cervicothoracic area. One month later, the area was imaged using 1.5T MRI in three dogs. The microchips were removed surgically together with the surrounding tissue in all dogs. There was significant signal loss and image distortion over a wide range around the area where the microchip was implanted. This change was consistent with susceptibility artifacts, which rendered the affected area including the spinal cord undiagnostic. The artifact was more extensive in T2*-weighted images (gradient-echo) and less extensive in proton density-weighted images (fast spin-echo with short echo time). Histopathologically, all microchips were well-encapsulated with granulation tissue, and there were no evidence of migration of microchips. Cell debris and a moderate number of degenerated cells with fibrin were seen in the inner layer of the granulation tissue in each dog that underwent MRI. These changes were very subtle and did not seem to be clinically significant. The results of this study suggest that, in 1.5T MRI, susceptibility artifacts produced by implanted microchips can be marked, although the dogs with implants appeared to be scanned safely.

Open heart closure of an atrial septal defect by use of an atrial septal occluder in a dog.

CASE DESCRIPTION: A 3-year-old sexually intact male Standard Poodle was admitted to the veterinary teaching hospital for transcatheter closure of a large atrial septal defect (ASD). CLINICAL FINDINGS: The dog had exercise intolerance and was thin. Findings on physical examination were within normal limits with the exception of a left base systolic heart murmur (grade 5/6). The dog was not receiving any medications. Echocardiography and thoracic radiography confirmed the diagnosis of ASD and revealed compensatory changes consistent with a large left to right shunting ASD. Results of serum biochemical analysis and CBC were within reference range limits. TREATMENT AND OUTCOME: Transcatheter ASD closure with an atrial septal occluder (ASO) was performed and failed. An open heart surgical approach under cardiopulmonary bypass was declined by the dog's owners. The dog underwent a novel hybrid approach involving active device fixation under temporary inflow occlusion after transatrial device deployment. The dog recovered with some manageable postoperative complications. As of the last follow-up examination, the dog had 10 months of event-free survival. CLINICAL RELEVANCE: Transcatheter closure by use of an ASO and open heart patch repair with cardiopulmonary bypass to surgically treat dogs with ASD has been reported. Transcatheter closure is not possible in dogs with large ASD. The novel hybrid procedure reported herein represented a viable alternative to euthanasia.

Custom-made artificial eyes using 3D printing for dogs: A preliminary study.

Various incurable eye diseases in companion animals often result in phthisis bulbi and eye removal surgery. Currently, the evisceration method using silicone balls is useful in animals; however, it is not available to those with impaired cornea or severe ocular atrophy. Moreover, ocular implant and prostheses are not widely used because of the diversity in animal size and eye shape, and high manufacturing cost. Here, we produced low-cost and customized artificial eyes, including implant and prosthesis, using computer-aided design and three-dimensional (3D) printing technique. For 3D modeling, the size of the artificial eyes was optimized using B-mode ultrasonography. The design was exported to STL files, and then printed using polycaprolactone (PCL) for prosthesis and mixture of PCL and hydroxyapatite (HA) for ocular implant. The 3D printed artificial eyes could be produced in less than one and half hour. The prosthesis was painted using oil colors and biocompatible resin. Two types of eye removal surgery, including evisceration and enucleation, were performed using two beagle dogs, as a preliminary study. After the surgery, the dogs were clinically evaluated for 6 months and then histopathological evaluation of the implant was done. Ocular implant was biocompatible and host tissue ingrowth was induced after in vivo application. The custom-made prosthesis was cosmetically excellent. Although long-term clinical follow-up might be required, the use of 3D printed-customized artificial eyes may be beneficial for animals that need personalized artificial eye surgery.

Transcatheter atrial septal defect closure with the Amplatzer atrial septal occluder in 13 dogs: short- and mid-term outcome.

BACKGROUND: Transcatheter atrial septal defect (ASD) closure in the dog was first reported in 2005. OBJECTIVES: Describe the technique and both short- and mid-term outcome of transcatheter ASD closure with the Amplatzer atrial septal occluder (ASO). ANIMALS: Thirteen client-owned dogs with ASD. METHODS: Records of the initial 13 dogs in which transcatheter ASD closure was attempted at Texas A&M University were reviewed. RESULTS: All dogs had hemodynamically relevant septum secundum ASD. Two dogs had concurrent congenital abnormalities. ASOs were deployed in 13 dogs and released in 12. Eleven were released by a right jugular approach and 1 by a transatrial approach through a right lateral thoracotomy. Transthoracic echocardiographic estimates of ASD size were 14.0 + or - 5.4 mm (mean + or - 1 standard deviation) with a range of 7-22 mm. Accidental right atrial release occurred in 1 dog and embolization after release occurred in 2 dogs. Transcatheter ASD closure was successful in 10 dogs. Transthoracic color Doppler echocardiography the day after ASD closure indicated complete occlusion in 5 dogs, trivial to mild residual shunting in 4 dogs, and moderate residual shunting in 1 dog. Follow-up echocardiograms (mean of 12.4 + or - 7.4 months postprocedure) were available for 9 dogs. There was no residual ASD shunting in 6 dogs. In 3 of the 5 dogs with postoperative residual shunting it was judged to be decreased and hemodynamically unimportant relative to the dogs' postoperative evaluations. The mean length of event-free survival in the 10 dogs that underwent successful transcatheter ASD closure was 22.2 + or - 10.2 months.

Short-, intermediate-, and long-term results for endoluminal stent placement in dogs with tracheal collapse.

OBJECTIVE To evaluate outcomes following endoluminal stent placement for treatment of tracheal collapse (TC) in dogs. DESIGN Retrospective case series with nested observational study. ANIMALS 75 dogs that underwent endoluminal placement of a self-expanding metallic stent to treat TC between September 2009 and August 2015. PROCEDURES Medical records were reviewed to collect data on dog characteristics, clinical signs, TC type, diagnostic test results, peri- and postoperative complications, and outcomes. Complication rates and survival times and rates were compared between various groups. RESULTS The 75 dogs received 119 stents (56% [42/75] received 1 stent and 44% [33/75] received ≥ 2 stents). Thirty-eight (51%) dogs had a malformation type of TC, and 37 (49%) had the traditional type. Ninety-three percent (70/75) of dogs survived to hospital discharge. Median survival time was 1,005 days. Improvement in goose-honking or raspy breathing (89% [42/47]) and dyspnea (84% [43/51]) was reported at final follow-up examination. Major complications requiring additional stent placement procedures occurred in 47% (33/70) of dogs over the follow-up period; stent fracture and tissue ingrowth were the most common types. Male dogs and younger dogs had a significantly longer survival time than other dogs. Mainstem bronchial collapse at the time of stent placement had no significant association with outcome. CONCLUSIONS AND CLINICAL RELEVANCE Endoluminal stent placement provided a high survival rate for dogs with TC, even those with severe clinical signs. This information, as well as the information on potential complications, should be useful for advising owners of affected dogs.

Correlations among tracheal dimensions, tracheal stent dimensions, and major complications after endoluminal stenting of tracheal collapse syndrome in dogs.

BACKGROUND: Endoluminal tracheal stenting can relieve signs associated with tracheal collapse syndrome (TCS) in dogs, but major complications can result. OBJECTIVE: To identify associations among tracheal dimensions, stent dimensions, and subsequent complications requiring additional stent placement after endoluminal stenting for TCS. ANIMALS: Fifty-two dogs from the hospital population. METHODS: Medical records of dogs that received an endoluminal self-expanding tracheal stent for TCS by the interventional radiology service between 2009 and 2014 were reviewed for relevant data. Signalment and clinical details, including tracheal collapse type, tracheal measurements, nominal stent dimensions, follow-up evaluation times, and stent complications, were recorded. RESULTS: Fifty-two dogs that received an endoluminal stent for TCS met the inclusion criteria. Major complications included stent fracture (13/52; 25%), obstructive tissue ingrowth (10/52; 19%), and progressive tracheal collapse (6/52; 12%). Natural tracheal taper (P = .04) and more stent diameter oversizing (P = .04) in the intrathoracic (IT) trachea were associated with caudodorsal stent fracture. Only stents with a 14-mm nominal diameter fractured. Progressive tracheal collapse was associated with smaller maximum tracheal diameters (P = .02). The majority of dogs with obstructive tissue ingrowth (7/10; 70%; P = .30) and all dogs with thoracic inlet fractures (3/3; 100%) had tracheal malformations. CONCLUSIONS AND CLINICAL IMPORTANCE: A higher taper in tracheal diameter may lead to increased risk of fracture in the IT location. Dogs with tracheal malformations may have higher risk for thoracic inlet fracture and development of obstructive tissue ingrowth. Clinicians should be aware of the possible risk factors for tracheal stent complications.