KEY WORDS
Donor site morbidity - phalloplasty - prefabricated flap
INTRODUCTION
Phalloplasty is commonly indicated for penile loss (secondary to trauma, infection and tumour ablation), transsexuals, congenital anomalies,[1] ectopia vesicae complex.[2] There are numerous methods described for phalloplasty; these methods include various pedicled and free flaps. The ideal phalloplasty should have following: one stage procedure that is predictable and reproducible, minimal donor site disfigurement, no functional loss, aesthetically acceptable phallus including a competent neourethra that will allow for voiding while standing with tactile and erogenous sensations and enough bulk to tolerate the insertion of the erectile prosthesis for sexual intercourse.[3]
The technique closest to ideal phalloplasty is radial forearm free flap phalloplasty. Major advantages of this flap are use of hairless skin for urethral reconstruction, very good sensations due to the incorporation of multiple sensory nerves in flap, good aesthesis as the flap vascularity is very robust and it can be moulded easily. Apart from other complications, this technique is associated with donor site morbidities such as impaired healing, poor scarring, unaesthetic result and varying degree of functional loss. The major disadvantage of this flap is its donor site morbidity including a readily apparent and potentially stigmatising scar on forearm.[4]
There are many techniques illustrated in the literature to reduce down the donor site morbidity of smaller radial forearm flaps as commonly used for head neck reconstruction and trauma. The soft tissue defect of radial forearm flap for phalloplasty is large often involving near total or total circumference; these measures cannot be applied to the phalloplasty donor area.
PROCEDURE
We present here a noble method of minimising the donor area morbidity of phalloplasty using prefabricated thigh flap. This patient a 35-year-old female wants gender reassignment surgery. After psychiatric consultation and completing the legal formalities, patient underwent subcutaneous mastectomy, hysterectomy, oophorectomy, vaginectomy in various stages. The patient was very conscious about the post-surgical skin grafting scar on the forearm.
The prefabrication of the right thigh flap was done as per markings of standard anterolateral thigh (ALT) flap. The descending branch of the lateral circumflex femoral artery was dissected away from the muscle keeping fatty cushion around it. The skin over the ALT region was dissected in the subcutaneous plane to reduce the thickness of the flap. The proximal part of the pedicle was encased in silicon sheet, and distal part was placed over the tissue expander (volume 500cc) placed in the subcutaneous plane. Hence, the distal part of the descending branch of lateral circumflex femoral pedicle was sandwiched between tissue expander and subcutaneous tissue and was stabilised there with anchoring stitches.
Expansion of tissue expander was started on the 10th post-operative day; weekly expansions were done till adequate size was reached. On attaining the desired size, the expander was left in situ for 3 months. Delay of the prefabricated thigh flap was done by cutting the skin on the lateral margins and stitching back 3 weeks before proposed phalloplasty [Figure 1]. Vascularity of the descending branch of lateral circumflex femoral artery to delayed flap was confirmed over the expander with the help of handheld Doppler. On the day of phalloplasty, simultaneous harvesting of radial forearm flap for phalloplasty and delayed thigh flap for donor area was done. The delayed thigh flap was dissected and isolated on one artery and 2 veins in the pedicle [Figure 2]. The delayed flap was measuring 30 cm × 14 cm [Figure 3]. The flap was thin and pliable. The silicone sheet had isolated the pedicle hence making the dissection proximally easy.
Figure 1: Prefabricated flap in the thigh
Figure 2: Harvested flap demonstrating the pedicle
Figure 3: Harvested flap showing dimensions
Radial forearm phalloplasty was done in a standard tube-within-a-tube method. After the radial forearm flap was divided and taken to perineum for anastomosis, the thigh flap was divided. The phalloplasty flap had consumed near total forearm skin except a skin bridge of 4 cm dorsally [Figure 4]. The thigh flap was temporarily stabilised with staples on the forearm and anastomosis was done with radial artery and venae comitantes [Figure 5]. The flap could cover whole of the donor area defect without the need of skin graft [Figure 6]. Meanwhile, the donor area of thigh flap was closed primarily obviating the need for skin graft in whole procedure [Figure 7].
Figure 4: Donor area defect on forearm
Figure 5: Prefabricated flap covering the donor defect
Figure 6: Aesthetically good result of donor area
Figure 7: Primary closure of thigh, forearm defects and newly reconstructed phallus
DISCUSSION
The Russian surgeon Nicoloj Bograz performed the first reconstruction of total penis using rib cartilage in a reconstructed phallus made from a tubed abdominal flap in 1936.[5] The first female to male gender reassignment surgery was performed in 1946 by Sir Harold Gilles on fellow physician Michael Dillon.[6] Following these earlier flaps numerous pedicled flaps were tried for phalloplasty like groin flap[7] with or without Iliac crest bone, abdominal flaps,[8] island TFL flaps[9] and recently pedicled ALT flaps.[10]
With the advent of microsurgery, one stage reconstruction of the phallus with free tissue transfer became a reality. Not only does the number of surgeries reduced but the aesthesis of reconstructed phallus, the tactile and erogenous sensations also improved.[11] Chang and Hwang popularised the tube within–a–tube design in 1980 using the radial forearm flap.[12] Radial forearm flap soon became gold standard flap for phalloplasty.[13] Apart from these many free flaps are used for phalloplasty-Latissimus dorsi flap,[14] free fibular flap,[15] ulnar artery flap,[16] lateral arm flap,[17] free ALT flap[18] and scapular flap.[19]
Donor area morbidity remains the unsolved problem in all these techniques. Donor area disfigurement of ALT flap, fibular flap, scapular flap is not much bothering as it is hidden in the clothing usually. Donor area of radial forearm flap being at exposed area troubles more. Many techniques are used to reduce the donor site morbidity of radial forearm flaps-suprafascial dissection, split thickness skin graft, full thickness skin graft, tissue expansions, use of artificial dermis, local flaps.[4] None of these techniques could reduce the unaesthetic appearance of forearm significantly although skin graft may do fairly well in some situations.
The phalloplasty and use of prefabricated thigh flap for donor area as in this case requires double free flaps. The total operating time is not prolonged as both the flaps are harvested and anastomosed simultaneously. It needs a dedicated team with good experience in microsurgery.
The use of prefabricated flaps for penile reconstruction has been enumerated in literature many times.[20]
[21] Rieger et al. have used the free groin flap to minimise the donor area morbidity by partially covering it and demonstrating good results both aesthetically and functionally.[22] However, there has been no reported case of use of prefabricated flap to cover the whole donor area of radial forearm phalloplasty without using skin graft minimising the donor area morbidity.
CONCLUSION
This new technique of using prefabricated thigh flap has significantly reduced the donor site morbidity both aesthetically and functionally without the use of skin grafting in whole procedure. The use of prefabricated flap has shown good aesthetic result but at the cost of multiple surgeries.
Financial support and sponsorship
Nil.
