Surgery of the Penis and Prepuce Flashcards
What is hypospadia?
A rare developmental abnormality affecting the male genitalia which is the result of the foetal urogenital fold failing to fuse
Where is the urethral opening in hypospadia?
more ventral and caudal to normal, which can be anywhere along its length
How do we classify hypospadia? Examples (5)
The location of the urethral opening is used to classify hypospadias and as such it can be described as glandular, penile, scrotal, perineal or anal.
Most common breed affected by hypospadia?
Boston terrier
What is the effect of hypospadia on the penis and prepuce?
ncomplete on the ventral aspect, underdeveloped and/or abnormal
Term used to describe irritation of the penis and preputial lining.
balanoposthitis
Differentials for hypospadia. (5)
Hermaphroditism
Pseudohermaphroditism
Trauma
Urethral fistula
Penile hypoplasia
When is diagnostic imaging needed in hypospadia?
useful to identify other congenital or developmental abnormalities in affected individuals.
What does hypospadia treatment depend on?
Classification and degree affected?
What is the medical management aims of hypospadia?
Attempts to manage urine scalding and irritation medically with barrier creams/ointments and daily preputial flushing with physiologic saline can be made.
When is surgery NOT required in hypospadia cases?
Where the external urethral orifice remains near the cranial end of the penis
What surgical approach might be needed to be taken in hypospadia?
reconstruction or amputation/excision of the penile defect may be necessary in combination with appropriate urethrostomy surgery.
What is recommended in cases of hypospadia for major deficits that involve the urethra, prepuce and penis?
Excision of the penile remnants and urethrostomy is recommended.
What age for surgical approach of hypospadia in pediatric patients?
Delay until 8 weeks due to GA considerations
Which area of the penis bleeds profusely if wounded?
Cavernous tissue
What trauma of penis can lead to a deviation?
of os penis
What swelling might occur If a penile wound is deeper and causes disruption to the penile urethra, urine leakage or extravasation can occur? (2)
diffuse periputial or inguinal swelling.
What imaging is useful to determine urethral involvement in a wound?
Contrast studies
What are the risks of penile wound healing without intervention? (4)
- Fistula formation
- Persistent haemorrhage urine extravasation
- Infection
- Stricture
If a penile wound involves the urethra, without complete transection, what can be done and for how long?
Passing a urinary catheter and keeping this in place for 5-7 days
If trauma has caused urethra transection, what approach should be taken?
urethral anastomosis or a more caudal urethrostomy will be required.
If a urethral catheter cannot be placed following trauma; what can be placed?
Tube cystotomy
How can penile wounds be closed?
- layer
- material
- needle
tunica albuginea
- Absorbable monofilament suture material
- Swaged on, taper point needle. 1.5-0.7 metric sizes are appropriate (4-0 to 6-0).
Steps for a penile amputation.
- Retract the prepuce and place a temporary tourniquet around the penis, caudal to the affected area.
- A V-shaped incision is made on the lateral aspect of the penis through the tunica albuginea and the cavernous tissue.
- Cut the os penis as far caudally as is feasible
- Transect the urethra 1-2 cm distal to the penile transection and incise along the length to spatulate the remaining end.
- Suture the urethral mucosa to the tunica albuginea using monofilament absorbable sutures.
- Shorten the prepuce so that exteriorisation of the distal portion of the remaining penis is possible.
Neoplasms can also arise on the mucosal lining of the prepuce and or the penis. Name.
transmissible venereal tumour (TVT), squamous cell carcinoma, haemangiosarcoma, papilloma and osteosarcoma of the os penis
Best treatment for transmissible venereal tumour (TVT)?
weekly vincristine-based chemotherapy, with remission usually possible after the 6th week.
Apart from chemo, other treatment options for transmissible venereal tumour (TVT)?
Radiotherapy and surgery (partial or complete penile amputation with scrotal or perineal urethrostomy)
Prognosis for transmissible venereal tumour (TVT) if treated with chemo/radiotherapy?
Total remission prognosis- good
Define paraphimosis
The protrusion of the penis with inability to retract into the prepuce.
Define phimosis
impossible to extrude the penis from the prepuce
Congenital stenosis of the preputial opening has been reported in what breeds? (5)
Bouvier des Flandres
German Shepherds
Labradors
Golden Retrievers
Mixed breed dogs
Breed predisposition to congenital phimosis
None
What may acquired phimosis be preceded by? (3)
Trauma
Neoplasia
In puppies - excessive licking by others/mum
Why can preputial and penile irritation develop with phimosis?
secondary to urine pooling and distension of the prepuce.
Define Balanoposthitis
inflammation of the penis and preputial lining
How is phimosis diagnosed?
based on a clinical exam identifying a narrowed or absent preputial opening and inability to extrude the penis
When is imaging required in phimosis?
Imaging is rarely necessary unless the condition is acquired secondary to neoplasia or trauma.
How can the preputial opening be widened surgically?
The craniodorsal aspect of the existing preputial opening is incised with a full thickness wedge of tissue being removed. The preputial mucosa and skin edge are then apposed using a simple interrupted monofilament absorbable suture on either side.
What would happen surgically in severe cases of phimosis?
In more severe cases, the distal portion of the prepuce may require amputation in order to achieve an adequately sized preputial opening.
How is paraphimosis congenital?
Congenital narrowing +/- shortening of prepuce
How is paraphimosis acquired? (5)
trauma
neoplasia
constriction with preputial hair
following sexual activity
secondary to priapism
Define priapism
Persistent erection of the penis without sexual excitement
How to diagnose paraphimosis
Clinical exam
When is imaging needed for paraphimosis
If suspect urethra involved
How to reduce oedema in cases of paraphimosis?
Hyperosmotic material such as sugar can be considered to reduce oedema.
Once the penis is replaced following paraphimosis, what should happen next, and meds to go home with.
If replacement of the penis within the prepuce is subsequently possible a loose purse string suture can be placed to temporarily (36-48 hours) to maintain the reduction. Anti-inflammatory medication may be appropriate
If conservative management is not possible with paraphimosis, what surgery may be necessary? (to allow retraction followed by..)
A preputiotomy may be necessary to allow retraction of the penis with preputial reconstruction, phallopexy or penile amputation subsequently required.
Surgical option for paraphimosis With narrow preputial openings causing a secondary paraphimosis?
Techniques to increase the opening size, such as those used in phimosis, can be used;
Surgical option for paraphimosis with a short prepuce which does not cover the penis sufficiently?
The prepuce can be advanced, or the penis amputated or anchored to the peputial mucosa (phallopexy);
Surgical option for paraphimosis in cases where the penis is able to be replaced into the prepuce?
Phallopexy can be used to prevent recurrence
Surgical option for paraphimosis in cases where paraphimosis occurs secondary to sexual activity?
Castration
How to perform a phallopexy? Including material
A portion of mucosa from the dorsal surface of the penis and from the preputial mucosa 2-3 cm from the preputial opening. These incisions are then apposed using 3-0 or 4-0 monofilament absorbable sutures.
Preputial advancement:
A) Position for surgery?
B) What shape incision is made around the prepuce?
A) Dorsal recumbency
B) Crescent shape
Following the initial incision for a preputial advancement; what are the next steps?
incision is made around the prepuce allowing the prepuce to be dissected as a flap from its body wall attachment. The prepuce can then be pulled cranially until the penis is covered and a surgical pen used to mark this position on the abdominal skin cranial to the initial incision.
A second crescent incision is then made at the cranial aspect of the abdominal incision, joining with the first and the segment of redundant abdominal skin removed.
The exposed preputial muscles can then be transected and re-apposed or plicated and secured with sutures before the abdominal and preputial skin are closed routinely.
How can a preputioplasty narrow the preputial office?
By opposing two incisions made on the ventral part of the preputial opening.
