Cosmetic globe surgery in the horse

Al-thnaian TA, Alkhodair KM, Tharwat M, El-Sherif MW. A modified supraorbital surgical approach for enucleation- exenteration in dromedary camels (camelus dromedarius): Clinical study

Enucleation and exenteration are widely utilized ophthalmic procedures in veterinary field. Enucleation in camels is like other large animals, typically performed under the influence of heavy sedation and loco-regional analgesia. The aim of the current study was to introduce a new surgical approach to enucleate the eye of camels through supraorbital fossa approach. for that purpose, the technique was applied to seven camels referred to the King-fisal teaching veterinary hospital for unilateral enucleation. Assessment of applicability, safety and feasibility of this technique was done. All procedures were performed in the kush (sitting) position under the influence of heavy sedation with Xylazine HCl in combination with retrobulbar nerve block. A "C" shaped skin incision was made in the skin and fascia of the supraorbital fossa to enter the orbital cavity, after which the periorbital fat was gripped, dissected and removed. Bleeding controlled by electrocautery and visible large blood vessels were ligated. After ligation the optic nerve and ophthalmic blood vessels, the eyeball was dissected sharply and freed from the orbital bony attachment. Finally, the orbital fascia and skin were sutured with simple interrupted pattern separately. The approach proved successful in all camels, with the enucleation procedure being both feasible and easily performed. The mean surgical time was approximately 46.6±12.4 minutes. The minimal occurrence of short and long-term complications was encouraging, and the cosmetic outcomes were notably improved. The supraorbital approach is a safe and effective technique for camel ophthalmic surgery, showing advantages in exposure and minimal complications. Further research is needed for validation and broader clinical applications.

Subconjunctival enucleation with orbital implant placement in standing horses: 20 cases (2014-2017)

OBJECTIVE

To develop a protocol for subconjunctival enucleation and orbital implant placement in standing horses and to document short- and long-term complications, cosmesis, and client satisfaction.

ANIMALS

20 horses with nonneoplastic ocular disease requiring enucleation.

PROCEDURES

A standardized protocol of surgical suite cleaning, patient preparation, sedation, local nerve blocks, surgical procedure, and postoperative care was performed. Owners were required to provide follow-up information at 1 year after surgery during a phone questionnaire. Additionally, some owners provided follow-up information at 1.8 to 4 years postoperatively.

RESULTS

11 mares, 6 geldings, and 3 stallions with a mean age of 9 years (range, 0.5 to 25 years) were included in this study. Reasons for enucleation included corneal lacerations (n = 3), perforated ulcers (4), end-stage uveitis (7), fungal keratitis (3), endophthalmitis (1), glaucoma (1), and stromal abscess (1). The mean surgery time was 64 minutes (range, 50 to 83 minutes). The most common implant size used was 45-mm diameter (range, 43- to 47-mm diameter). Complications included mild postoperative colic (n = 4), incisional swelling (1), and drainage from the surgical site (1) that resolved without implant removal. One-year follow-up information was available for 19 of 20 horses. Fourteen owners were very satisfied and 5 owners were satisfied with the cosmetic appearance. One horse was lost to follow-up.

CONCLUSIONS AND CLINICAL RELEVANCE

Subconjunctival enucleation and orbital implant placement in standing horses was a safe and efficient alternative to general anesthesia when a standardized perioperative protocol was used. No horse developed clinically relevant complications, and owner satisfaction and cosmesis were good.

A multicentre study of long-term follow-up and owner satisfaction following enucleation in horses

BACKGROUND

Horses are reported to return to a variety of disciplines following unilateral enucleation; however, owners of horses with ocular disease are frequently reluctant to consider the procedure. There is little published information investigating owners' attitudes towards, and satisfaction following, enucleation.

OBJECTIVES

To investigate the hypotheses: 1) horses return to their previous level of work following unilateral enucleation and 2) their owners are satisfied with the post-operative outcome.

STUDY DESIGN

Retrospective case series with cross-sectional survey.

METHODS

Clinical records from eight equine referral centres in the United Kingdom were reviewed to identify horses that underwent enucleation between August 2006 and March 2015. Owner questionnaires were completed to corroborate information provided by medical records and obtain information on client perceptions.

RESULTS

A total of 170 cases were identified and 119 owner questionnaires completed. The most frequent primary uses of horses in the study were pleasure/leisure riding, showjumping and dressage, with 25.2% (n = 30) of horses used for competition. Following enucleation, 77.3% (n = 92) of horses were performing at an equivalent or higher level than prior to enucleation and 60.0% (n = 18/30) of competition horses were competing at an equivalent or higher level. Complications related to the surgical site (predominantly mild post-operative swelling) were reported in 3.7% of cases and nonocular complications in 3.7% of cases. Of owners who reported being concerned or very concerned about certain factors prior to surgery, ≥86.8% reported that these factors caused little or no issue post-surgery. Most owners, 90.8% (n = 108) were pleased with the outcome following surgery, with 21.3% (n = 23/108) wishing the procedure had been undertaken sooner.

MAIN LIMITATIONS

Retrospective data collection from clinical records and the potential for recall bias.

CONCLUSIONS

Horses can return successfully to a variety of disciplines following enucleation. Owners are satisfied with the outcome and pleased that enucleation was performed.

A retrospective analysis of the risk factors for surgical site infections and long-term follow-up after transpalpebral enucleation in horses

Background

Implants are often used to improve the cosmetic appearance of horses after enucleation of the eye. When surgical site infection (SSI) occurs, the implant will almost always be lost. The aim of this study is to collect data on the risk factors for SSIs and report long-term follow-up (cosmetic results and return to work) after transpalpebral enucleations. In this retrospective study, records of horses undergoing transpalpebral enucleation were reviewed (2007–2014) and telephone interviews were used to obtain long term follow-up. The potential risk factors for SSIs (indication for enucleation, use of an implant, standing procedures, duration of surgery, opening of the conjunctival sac and prolonged use of antimicrobials) were analysed for their association with the outcome measure ‘SSI’ vs ‘no SSI’ by multivariable binary logistic regression testing. Indications for enucleation were grouped as follows: Group 1 (clean) included equine recurrent uveitis, too small or too large globes, and intraocular tumours, Group 2 (non-clean) included corneal perforation/rupture and infected ulcers and Group 3 (tumour) included extraocular tumours.

Results

One hundred and seven cases of enucleation were evaluated. An implant was used in 49 horses. The overall number of SSIs was 8 (7.5%). Multivariable logistic regression testing showed implants (OR 7.5, P = 0.04) and standing procedures (OR 12.1; P = 0.03) were significantly associated with the percentage of SSIs and increased the risk of SSI. The eyes of horses in Groups 2 and 3 trended towards a larger risk for developing SSIs (OR 4.9; P = 0.09 and OR 5.9; P = 0.1, respectively). Prolonged use of antimicrobials, long surgery times and the opening of the conjunctival sac during dissection did not show significant associations with SSI risk.

Conclusions

The risk of SSI after enucleation is low in clean eyes and when no implant is used. Placing an implant or performing a standing enucleation significantly increases the risk of SSIs. Although implants can be used for eyes that fall into Groups 2 and 3, 17% of the horses in these two groups developed an SSI leading to loss of the implant.

Computed Tomography and Magnetic Resonance Anatomy of the Normal Orbit and Eye of the Horse

Traumatic and infectious diseases of the eye and orbit can occur in horses. For diagnosis and monitoring of such diseases, medical imaging is useful including computed tomography (CT) and magnetic resonance imaging (MRI). The aim of the current study was to describe CT and MRI anatomy of the equine orbit and ocular globe. The heads from four adult horses were scanned with a 6-slice Emotion 6 CT (Siemens, Erlangen), and a 3.0 Tesla Siemens Verio 6 MRI using T1 and T2-weighted sequences. To validate CT and MR reference images, these were compared with anatomical models and gross anatomical sections. The bony limits of the orbital cavity, the relationship of the orbit with sinuses and foramina of the skull were well identified by CT. MRI was useful to observe soft tissues and was able to identify adnexae of the ocular globe (eyelids, periorbital fat, extraocular muscles, lacrymal and tarsal glands). Although MRI was able to identify all components of the eye (including the posterior chamber), it could not differentiate sclera from choroid and retina. The only nerve identified was the optic nerve. Vessels were not seen in this series of cadaver heads. This study showed that CT and MRI are useful techniques to image the equine orbit and eye that can have clinical applications.

Comparison of orbital prosthesis motility following enucleation or evisceration with sclerotomy with or without a motility coupling post in dogs

OBJECTIVE

To evaluate motility of silicone orbital implants and corneoscleral prostheses, with and without use of a motility coupling post (MCP) in dogs.

ANIMALS STUDIED

Eighteen mixed-breed dogs.

PROCEDURES

The motility of an orbital silicone implant and corneoscleral prosthesis after enucleation (n = 6), evisceration (n = 6), or use of a MCP with evisceration (n = 6) in dogs were compared. One eye from each dog had surgery whereas the opposite eye was used as a control. Clinical evaluations were performed three times a week. Histopathology of the orbital tissues was performed 8 and 12 weeks after surgery.

RESULTS

Implant motility in dogs with evisceration (vertical movement [VM] 8.04 +/- 2.13; horizontal movement [HM] 11 +/- 3.05) and evisceration with MCP (VM 9.61 +/- 1.59); HM was significantly greater than the enucleation group (VM 0.51 +/- 0.5; HM 1.22 +/- 0.68) (P < 0.01). Prosthetic motility in dogs with evisceration with MCP was significantly greater than in dogs with evisceration; dogs with evisceration had significantly greater motility than dogs with enucleation (P < 0.01). No postoperative complications were observed in any of the groups. No significant abnormalities were noted on histopathology.

CONCLUSIONS

MCP placement in silicone orbital implants significantly enhanced the prosthetic motility in dogs. This study supports the use of MCP in silicone orbital implants to enhance corneoscleral prosthesis motility and cosmetics in dogs.