Page 215 - Manual of Equine Field Surgery

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CHAPTER 38

Perineal Urethrotomy in Males

Gal Keltner

. ,

1.5 cm in the urethral isthmus and penile urethra.
INDICATIONS

The urethralis muscle envelops the pelvic urethra.

The corpus spongiosum penis surrounds the

Treatment of urolithiasis involving the bladder urethra, and the bulbospongiosus muscle lies

and urethra, urethral rents causing hemosperrnia caudal to the pelvic urethra and beco1nes ventral

in stallions and hematuria in geldings, and tem- to the penile urethra distally. The symmetrical

porary urine diversion for urethral obstructive retractor penis muscle covers the bulbospongio-

lesions, such as hematoma, neoplasia (e.g., squa- sus and lies beneath the subcutaneous tissue at the

mous cell carcinoma), or parasitic granuloma perineal region.

(e.g., habronerniasis).!"

EQUIPMENT

A male urinary catheter is helpful for urethra iden- PROCEDURE

tification during surgery. When using urethro-

tomy to treat urolithiasis, special equipment such A vertical incision starts 4 to 6 cm distal to the

as a custom-made lithotrite may be necessary. anus and extends ventrally for 8 to 10 cm through

the median raphae skin and subcutaneous tissue

(Figure 38-1). The incision should not extend
PREPARATION AND POSITIONING
ventral to the ischium in order to prevent urine

spraying on the limbs and subsequent scald for-

The horse should be standing in stocks with the mation. The retractor penis muscles are separated

use of systemic sedation and epidural analge- on midline and reflected laterally (Figure 38-2).

sia. An alternative to epidural anesthesia is an The bulbospongiosus muscle is exposed and

inverted-V block L1siI1g local anesthetic. Manual incised. Hemorrhage is expected, at this stage,

emptying of feces from the rectum is followed by and is controlled by applying light pressure using

clipping, tail wrapping, and surgical preparation surgical gauze. The incision continues through

of the perineal region.
the corpus spongiosum penis and the urethral

wall. Urethral lumen entry is verified by visualiz-

ANATOMY ing and palpating the urinary catheter (Figure

38-3). The catheter helps to prevent both acci-

The male pelvic urethra is about 12 cm long and dental deviation from midline and penetration of

tapers i11 diameter from 3 cm near the prostate to the cranial urethral wall.!"

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