Evaluation of success rate of laparoscopic castration without orchidectomy in 32 mature horses

The surgical success of laparoscopic castration without orchidectomy results from avascular necrosis of the testes. However, failures and subsequent production of testosterone and stallion‐like behaviour have been previously identified. Laparoscopic castration without removal of the testes was performed in 32 horses with 2 normal descended scrotal testes between July 2006 and October 2012. The objectives of our study were to evaluate the success rate of laparoscopic castration without orchidectomy on descended testes in our population and assess complications and recovery time. Endocrine tests were performed after surgery and owners also asked to report on their horse's behaviour and ability to resume exercise. Castration was deemed successful if endocrine test results were in accordance with gelding values. Failed horses were castrated using a conventional technique and histology performed when possible. Basal testosterone levels decreased below 3 nmol/l after surgery in 30/32 cases. However, in 2 horses, stallion behaviour persisted and histological evaluation after inguinal castration showed residual viable tissue. Two horses maintained high testosterone levels after surgery associated with stallion‐like behaviour. Based on these results, 12.5% of horses (4/32 horses) failed to be considered a gelding based on either endocrine tests and/or histology. All horses, with one exception, were able to resume exercise less than a week after the procedure. Laparoscopic castration without orchidectomy appears to be a safe procedure. When assessing the success of laparoscopic castration, our total failure rate was 12.5% (4/32 horses) which is significantly higher than previously reported.     

The complex blood supply to the equine testis as a cause of failure in laparoscopic castration

REASONS FOR PERFORMING STUDY: Intra-abdominal ligation/ transection of the spermatic cord may result in necrosis of the testis; castration of abdominal cryptorchids via laparoscopy has therefore become common. Notwithstanding some adaptations of the technique, a small percentage of operations fail, prompting research into the anatomical background and clinical relevance of the procedure. HYPOTHESIS: That an alternate blood supply may prevent complete necrosis of the testis after spermatic cord transection. OBJECTIVE: To establish the prevalence of the problem in normal and cryptorchid stallions. METHODS: In a preliminary study, the spermatic cords of 8 normal stallions were ligated and transected at different sites and in various manners. Five weeks later the testes were removed and the vitality of both the testes and epididymes was evaluated. In a prospective clinical trial, intra-abdominal spermatic cord transection was performed in 241 cryptorchid and normal stallions. In cases of surgical failure, the testes were removed and histology performed. RESULTS: Examination of the specimen removed from the 8 animals of the preliminary study revealed that all epididymes were completely or largely spared. All except one testis were completely necrotic. In the patients that underwent surgery all abdominally retained testes (n = 123) were necrotic, while 5 out of 88 inguinally retained and 8 out of 236 normally descended testes had partially survived. The pattern of survival differed between inguinally retained and normally descended testes. The epididymes of these 13 horses were (largely) vital. The (partial) survival of the epididymes and inguinally retained testes was ascribed to an alternate blood supply via anastomosing vessels derived from the cremasteric artery. A tributary from the external pudendal artery was considered responsible for the partial survival of normally descended testes. CONCLUSIONS AND POTENTIAL RELEVANCE: After intra-abdominal transection of the entire spermatic cord, 5.6% of inguinally retained and 3.4% of normally descended testes failed to become completely necrotic, as a result of an alternate blood supply via the cremasteric and/or external pudendal artery. Therefore, laparoscopic castration without orchidectomy cannot be recommended as a trustworthy method for castration of inguinal cryptorchids and normal stallions.     

Inguinal percutaneous ultrasound to locate cryptorchid testes

Standing laparoscopic removal of abdominally retained cryptorchid testes may reduce patient morbidity and speed recovery compared with traditional laparotomy because anaesthesia is avoided and skin incisions are smaller. Reliably locating the testis preoperatively is therefore optimal to avoid unnecessary surgical morbidity and expense. We describe and review the results of a simple method of location using ultrasound scanning of the inguinal region, with a negative result indicating abdominal retention. One hundred and twenty‐seven horses with 141 cryptorchid testes were identified. Eighty‐five testes were identified inguinally: 56 abdominal. Two inguinally retained testes were not observed on ultrasound (false negatives) and 2 testes were considered inguinal but subsequently had to be removed from the abdomen (false positives). Sensitivity of inguinal ultrasound to predict the location of cryptorchid testes was therefore 98% and specificity 97%. The technique described herein proved a reliable technique to locate cryptorchid testes prior to surgery, minimising morbidity and cost. Suspect cryptorchids with no external evidence of testes should undergo a screening blood test prior to this ultrasound method of diagnosis.     

Castration of the Vietnamese pot-bellied boar: 8 cases

Surgical techniques for castration of the Vietnamese pot-bellied boar and outcome are described. Vietnamese pot-bellied pig (VPBP) boars (n = 8) were admitted for castration. Data retrieved from medical records (2002–2011) for these pigs included signalment, history, reason for castration, perioperative management, surgical technique, and complications. Follow-up information was obtained from owners. A scrotal approach with closed technique was used for 6 boars with normally descended testes. A scrotal approach and open technique was used in 1 inguinal cryptorchid boar. In a hemicastrated abdominal cryptorchid boar an ipsilateral parainguinal approach was used. No complications occurred. Castration of the Vietnamese pot-bellied boar is associated with minimal complications and a satisfactory cosmetic outcome. We recommend the routine closure of the external inguinal rings, a simple and fast procedure that may prevent post-castration inguinal herniation.     

Cryptorchidism and monorchism in cats: 25 cases (1980-1989).

Of 1,345 cats admitted for orchiectomy during a 10-year period, 23 (1.7%) were cryptorchid and 2 (0.1%) were monorchid. Persian cats were over-represented in the cryptorchid population (P = 0.01). Cats were more likely to be unilaterally than bilaterally cryptorchid (P = 0.01). A predisposition for location of undescended testes (abdominal vs inguinal or right vs left side) was not identified in unilateral cryptorchids. All bilateral cryptorchids had abdominally located testes. The most common surgical approaches used for orchiectomy of cryptorchid cats were a caudal ventral midline incision for inguinal testes and a caudal ventral midline celiotomy for abdominal testes.     

Laparoscopic Cryptorchid Castration in Standing Horses

Objective — This article describes a new technique for laparoscopic cryptorchid castration in standing horses. Study Design — Prospective study. Animals or Sample Population — Eight horses aged 11 months to 3 years and weighing between 300 and 643 kg. Methods — Food was withheld for 24 to 36 hours, and then horses were sedated with detomidine HC1 (0.02 to 0.03 mg/kg) and butorphanol tartrate (0.02 mg/kg). The paralumbar fossa region was desensitized with 2% mepivacaine in an inverted “L” pattern and caudal epidural anesthesia was administered with either xylazine (0.18 mg/kg diluted to 10 to 15 mL with 0.9% sodium chloride) or a combination of 2% mepivacaine and xylazine (0.18 mg/kg). Initial laparoscopic exploration was performed from the left flank; in three horses, right flank laparoscopy was needed to complete the procedure. The spermatic cord was ligated within the abdomen with one or two sutures of 0 polydioxanone suture, and the testis or testes removed through a flank incision. Results — In five horses with no palpably descended testes, standing laparoscopy was the only procedure performed, whereas in two horses, the abdominal testis was removed laparoscopically, and the descended testis was removed under short acting anesthesia. In one horse, with nonpalpable testes, it was determined by laparoscopic observation that the testes were in the inguinal canal, and castration was performed under general anesthesia. No surgical or postoperative complications were noted. The right side of the abdomen, and especially the right vaginal ring, could be easily observed from the left side by passing the laparoscope through a small perforation in the mesocolon of the descending colon or by elevating the descending colon with an instrument or by use of an arm in the rectum. Conclusions — The standing laparoscopic approach combined with or without short-acting anesthesia to remove the descended testis is easily performed. Clinical Relevance — This approach will provide surgeons with another option to castrate cryptorchid stallions.     

Comparison of the diagnosis and management of unilaterally castrated and cryptorchid horses at a referral hospital: 60 cases (2002-2006)

OBJECTIVE: To determine the incidence of unilaterally castrated horses among horses admitted to the hospital for castration and to compare horses that underwent previous unilateral castration with horses that had cryptorchism. DESIGN: Retrospective case series. ANIMALS: 16 unilaterally castrated horses and 44 cryptorchid horses. PROCEDURES: Medical records of horses that were admitted to the veterinary medical teaching hospital for castration, including cryptorchid and unilaterally castrated horses, between January 2002 and December 2006 were reviewed. Medical records of unilaterally castrated horses and cryptorchid horses were examined for age, breed, history, diagnostic procedures, surgical technique of cryptorchidectomy, location of the retained testicle, and cost of surgery. RESULTS: Of 160 horses admitted for castration, 16 (10%) had undergone previous unilateral castration and 44 (27.5%) had cryptorchidism. Unilaterally castrated horses were significantly older than cryptorchid horses. No significant difference was found in left versus right distribution of testicles. No significant difference was found in abdominal versus inguinal distribution of left-sided testicles. Unilaterally castrated horses had a significantly lower proportion of right inguinal testicles, compared with cryptorchid horses. The cost of diagnosis and management of unilaterally castrated horses was significantly greater than in cryptorchid horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the distribution of retained testicles is significantly different in unilaterally castrated horses, compared with cryptorchid horses, which may affect the selection of diagnostic and surgical approaches to unilaterally castrated horses.     

Unsuccessful laparoscopic castration in a cryptorchid Frisian stallion

A 2-year-old unilateral inguinal cryptorchid Frisian stallion was castrated by bilateral laparoscopic intra-abdominal spermatic cord transection. Because blood testosterone levels were still high on postoperative day 7, both testicles were removed using an open approach. Pathology revealed the presence of vital Leydig-cells in both testes. Failure of the laparoscopic castration in this horse was attributed to an alternate blood supply to the testes by vessels derived from the cremaster and/or external pudendal artery.     

A Review of Laparoscopic Cryptorchidectomy

Laparoscopic cryptorchidectomy has provided the surgeon with an easy, efficient means of locating and castrating abdominally retained testes without the complications associated with routine open approaches. It is especially useful when the horse's castration history is unknown, or if previous attempts at cryptorchid castration have been made. With the direct visualization that laparoscopy provides, surgeons are able to visualize both vaginal rings for presence of intra abdominal and inguinal testis in addition to testicular remnants and adhesion formation from previous surgical manipulations. Furthermore, because it is minimally invasive, laparoscopy shortens patient confinement time and reduces postoperative complications such as eventration. With experience, it is a technically easy procedure and can safely be performed on anesthetized or standing sedated horses.     

Morphological and immunohistochemical studies in testes of normal and cryptorchid boars

Scrotal (n = 66), inguinal (n = 7) and abdominal (n = 36) testes from pigs differing in age (from 1 day to 4 years) were collected after slaughtering or by castration, fixed in 4% formalin and examined by light microscopy. The expression of vimentin, desmin, alpha-actin and PCNA was detected by immunohistochemical technique. Histologically no differences between scrotal and cryptorchid testes are obvious during the prepubertal period, until the age of 10-12 weeks, but with the onset of puberty degenerative alterations (Sertoli-cell-only morphology, giant cells) in dystopic testes occur. Additionally the differentiation of the interstitial cells is disturbed in abdominal testes resulting in a deviating expression pattern of alpha-actin. The Sertoli cells show different distribution patterns (basal, perinuclear, apical) of vimentin depending on the position of the testis and the age of the animal.     

Laparoscopic Cryptorchidectomy in Standing Horses

Objective — The purpose of this study was to determine the feasibility of using laparoscopy to remove cryptorchid testes from standing horses.
Study Design — Prospective clinical study.
Animals or Sample Population — Eleven client-owned horses ranging in age from 4 months to 2 years.
Methods — Abdominal insufflation was initiated and maintained using a 20 F insufflation tube, attached via a stopcock, to the low pressure regulator on a standard carbon dioxide pressure tank. After trocar and laparoscope placement in the ipsilateral flank the testes were identified. Local anesthesia of the structures to be manipulated was administered through the instrument channel on the operative laparoscope, using a catheter with a needle attached. Testes were grasped with large laparoscopic forceps and exteriorized through the abdominal wall. Ligation and transection of the mesorchium was extracorporeal. The descended testes were removed using a standard standing technique.
Results — Complications were minor, including mild colic in one horse. The mean surgical time for standing laparoscopic cryptorchidectomy and castration of these colts was 58.9 ±24.3 minutes.
Conclusions and Clinical Relevance — Standing laparoscopic cryptorchidectomy, using the instrumentation described, is a safe and practical technique in young horses.     

Cystic Rete Testis in a 3-Year-Old Gypsy Vanner Colt: A Case Report

A 3-year-old Gypsy Vanner colt was presented at the Auburn University College of Veterinary Medicine for castration. The left testicle of the horse was present within the scrotum, but neither the right testicle nor the epididymis was found during external palpation of the right inguinal ring. Removal of the retained testicle by a routine inguinal approach by traction on the gubernaculum and dilation of the internal inguinal ring was not possible. During a parainguinal approach to the abdomen, an enlarged cystic testicle was discovered. Histopathologic diagnosis was cystic rete testis. This case report stresses the importance of preoperative ultrasonographic assessment of cryptorchid testicles to decrease surgical time.     

Laparoscopic‐assisted diagnosis of anomalous unilateral abdominal cryptorchidism

This report describes an unusual case of unilateral abdominal cryptorchidism in a Shetland pony. On the cryptorchid side, no testicular structures were present in the inguinal area but testicular/epididymal remnants at the distal end of a pedunculated structure could be discerned in the abdomen at laparoscopic examination. Furthermore, the deferent duct was disconnected from the epididymal remnants and the deferent duct was visible at the caudal aspect of the bladder, traversing over the lateral ligament of the bladder into the vaginal ring where it ended blindly in the vaginal process. After laparoscopic removal of the testicular/epididymal remnants and castration of the contralateral normally descended testicle, the hCG stimulation test was negative and the pony no longer exhibited masculine behaviour.     

Laparoscopic cryptorchidectomy in a cat

Several techniques for castration of cryptorchid cats have been described. In this case report, the use of laparoscopy for castration of a bilateral cryptorchid cat (with testes located in the abdomen) is described. Three trocars were inserted into the abdominal cavity, the testicles were easily identified adjacent to the urinary bladder. Haemostasis of the gubernaculum testis and spermatic cord was achieved with bipolar cauterisation. The testicles were easily removed in approximately 20 min. To the authors' knowledge this is the first report of the use of laparoscopy for the treatment of cryptorchidism in cats.     

Equine castration: review of anatomy, approaches, techniques and complications in normal, cryptorchid and monorchid horses

Complications associated with equine castration are the most common cause of malpractice claims against equine practitioners in North America. An understanding of the embryological development and surgical anatomy is essential to differentiate abnormal from normal structures and to minimise complications. Castration of the normal horse can be performed using sedation and regional anaesthesia while the horse is standing, or under general anaesthesia when it is recumbent. Castration of cryptorchid horses is best performed under general anaesthesia at a surgical facility. Techniques for castration include open, closed and half-closed techniques. Failure of left and right testicles to descend occurs with nearly equal frequency, however, the left testicle is found in the abdomen in 75% of cryptorchid horses compared to 42% of right testicles. Bilateral cryptorchid and monorchid horses are uncommon. Surgical approaches described for the castration of cryptorchid horses include an inguinal approach with or without retrieval of the scrotal ligament, a parainguinal approach, or less commonly a suprapubic paramedian or flank approach. Laparoscopic castration of cryptorchid horses has recently been described but the technique has limited application in practice at this time. A definitive diagnosis of monorchidism can only be made after surgical exploration of the abdomen, removal of the normal testis and hormonal testing. Hormonal assays reported to be useful include analysis of basal plasma or serum testosterone or oestrone sulphate concentrations, testosterone concentrations following hCG stimulation, and faecal oestrone sulphate concentrations. Reported complications of castration include postoperative swelling, excessive haemorrhage, eventration, funiculitis, peritonitis, hydrocele, penile damage and continued stallion-like behaviour.     

Use of transabdominal ultrasonography to determine the location of cryptorchid testes in the horse

REASONS FOR PERFORMING STUDY: Transrectal ultrasonography is a reliable technique to identify intra-abdominal testes, but can be hazardous or impractical in fractious, juvenile or small equids. The transabdominal approach therefore requires validation. OBJECTIVES: To evaluate the sensitivity and specificity of transabdominal ultrasonography to localise cryptorchid testes. METHODS: Thirty-eight horses admitted for cryptorchidism underwent transabdominal ultrasonography to locate errant testes. Location of the testes was confirmed during surgery (n = 37) or necropsy (n = 1). RESULTS: Horses weighed 175-760 kg. Twenty-two testes were located within the abdomen, 19 in the inguinal space and 3 in a subcutaneous location. In 2 horses, a thick winter coat prevented adequate contact between the probe and the skin, and visualisation of their inguinal testis and one abdominal testis was missed during transabdominal ultrasonography. Excluding the 2 horses with excessive hair, the sensitivity of transabdominal ultrasonography to locate errant testes was 97.6% (93.2% when all horses were included), and its specificity 100%. CONCLUSIONS: Transabdominal ultrasonography is a reliable, safe and immediate technique to diagnose cryptorchidism precisely in horses of all ages, sizes and temperaments. POTENTIAL RELEVANCE: Transabdominal ultrasonography provides an immediate definitive diagnosis of adominal cryptorchidism and should enhance selection of an appropriate surgical approach for their removal.     

Testicular ischaemic necrosis as a cause of equine cryptorchidism

Cryptorchidism is a fairly common pathology presented to equine surgical facilities with the cryptorchid testicle most commonly located in the abdomen or ipsilateral inguinal canal. The causes of cryptorchidism are not known, but testicular abnormalities have been suggested. Monorchidism as a cause of maldescent of one or both testicles is rare and is hypothesised to be the result of a vascular insult, similar to testicular regression in man. This case report details laparoscopic abdominal exploration of a cryptorchid horse and identification of an abnormal testicular remnant affected by ischaemic necrosis.     

Concentrations of oestradiol and testosterone in peripheral and spermatic venous blood of dogs with unilateral cryptorchidism

Plasma testosterone and oestradiol concentrations were measured in peripheral and spermatic venous blood of 13 dogs with unilateral inguinal cryptorchidism, 9 dogs with unilateral abdominal cryptorchidism, and in a control group of 36 mature normal dogs. The hormone concentrations were similar in the three groups, both in the peripheral and in the spermatic venous blood. The weight of the testes in the control group was correlated with the body weight and there was no significant difference between the weight of the right and the left testes. The weight of the abdominal testes was lower than that of the inguinal testes, and there was no compensatory enlargement of the contralateral scrotal testis. The cryptorchid testes showed little or no histological evidence of spermatogenesis, and spermatogenesis was usually normal in the scrotal testes.     

Use of an inguinal approach adapted from equine surgery for cryptorchidectomy in dogs and cats: 26 cases (1999-2010)

OBJECTIVE-To determine whether a surgical technique used in cryptorchid horses can be used successfully to remove testicles retained in the inguinal region or abdominal cavity in dogs and cats. DESIGN-Retrospective case series. ANIMALS-22 dogs and 4 cats with cryptorchidism. PROCEDURES-In 1999 through 2010, 26 cryptorchid patients underwent surgery during which an incision was made over the inguinal ring and the undescended testicle was located for removal via identification of the vaginal process and the embryonic gubernaculum. Castration was performed once a testicle was located in the inguinal region or via removal of an intra-abdominally located testicle through the inguinal canal. RESULTS-4 dogs and 1 cat were bilaterally cryptorchid. Testicles were retained in the abdominal cavity in 18 dogs and in the inguinal region in 4 dogs; in all 4 cats, undescended testicles were located in the inguinal region. Twenty-one dogs and 4 cats were castrated without breaching the abdominal cavity; in one of those dogs, the inguinal ring was enlarged to permit extraction of a tumorous testicle. In 1 dog, the inguinal ring was enlarged into a paramedian laparotomy and viscera were manipulated to exteriorize an intra-abdominally located testicle because the gubernaculum had ruptured. Major intraoperative or long-term complications did not occur. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that as in horses, the surgical approach over the inguinal ring, wherein the vaginal process and the remnant of the gubernaculum are identified and used to locate an undescended testicle for removal, can be used successfully in dogs and cats.