The interposition of a layer between the neourethra and the skin suture line represents one of the major technical advances in hypospadias surgery [9]. This principle has been introduced by Smith in 1973, when he described a de-epithelialized overlap flap to cover the neourethra in staged repair [10]. In his original report [10], Smith referred to his idea of skin shaving being previously described by Pers and Crawford [11]. The advantage of this overlap technique is that it allows for “tissue adhesion over a wide area rather than edge to edge healing” and without superimposed suture lines [10]. Currently, the dorsal dartos and the tunica vaginalis flaps (introduced later by Retik, and Snow, respectively) are the two more popular alternatives to cover the neourethra with different techniques of hypospadias repair [12-15].
In this report, we have revisited the original Smith technique [10], which we have found very suitable with the two-stage hypospadias repair. The de-epithelialized double-breasting skin closure offered excellent healing and support for the neourethra along the penile shaft, while complications were mainly restricted to the most distal (glanular) part. Although glanular dehiscence (partial or complete) was a common complication in this series, yet some experts may still consider subglanular/coronal meatus a success after proximal hypospadias repair [16], which can be both functional and cosmetically accepted [5]. We believe that multiple factors may be responsible for failure of glanular closure in patients with proximal hypospadias; the small size of the glans may be a major contributing factor. Moreover, the applied technique of de-epithelialized double-breasting skin closure may not be always sufficient to cover the whole length of the neo-urethra, especially at both ends. The proximal end of the neo-urethra can be covered by a nearby (readily available) scrotal dartos flap; however, the distal (glanular) end of the neourethra may be left unprotected by a second layer.
Proximal hypospadias represents a persistent challenge with no consensus on the best type of repair [17]. Preservation of the urethral plate seems to play a major role in recurrence of ventral curvature that may be under-reported [5,17]. Over the past years, a lower threshold to sacrifice the plate and stage the repair has been observed [19]. Flaps versus grafts in two stage repair remains a controversial debate in the literature [18]. A major concern about grafts is liability for contracture and shrinkage even after years [18]. In this report, we had a complication of urethral stricture in one case from the ‘graft’ group. However, discussing this major complication is beyond our scope in this report, and will be studied in a separate one.
The two-stage hypospadias repair was the standard in the 1960s and 1970s [5]. Later, in the 1980s, Duckett induced worldwide shift to one-stage repair by introducing the preputial island flaps [19]. The universal acceptance of the new concepts might have masked the success of the Smith’s de-epithelialized overlap flap. In 1988, Belman renewed the interest in the de-epithelialized flap applying it with modern techniques for hypospadias repair [20]; however, the dartos and tunica flaps were already taking over as more popular techniques for covering the neourethra. With the worldwide trend back to two-stage repairs [8], the Smith technique may be recalled to life in the 21st century.
In our experience, the Smith technique is much simpler and offers better healing than the tunica vaginalis flap. The latter is more invasive by dissection around the testis and is liable for contractures. Covering the neourethra by an intervening layer is not just for waterproofing [15], but also it can promote healing by providing neovascularity and growth factors [20]. This may be best achieved by using the subcutaneous tissue as a second layer for covering the neourethra.