The patients were usually admitted from the outpatients department. The carcinoma had often been present for two years or more, during which various local remedies had been tried. Common reasons for finally attending the hospital were bleeding, repeated secondary infections, pain and functional disruption of the nose. There was a strong preponderance of women, many of whom worked in the fields with headgear covering all but the nose. The patients' main concerns were the length of time they would be in hospital and how quickly they could return to their families and work.

Figure 1 Operation technique. From original paper by Converse (see Ref. 6)

Once the flap is raised, the incision is extended from the lateral border of the skin flap posteriorly with a coronal incision from the tip of one auricle to the apex of the other, incorporating the contralateral superficial temporal vessels. To ensure adequate length for a long columella and thus a good nasal tip, the flap is mobilized until the distal tip easily reaches the upper lip.⁷ The flap is then sutured down onto the nasal defect while the rest is folded in on itself without tension to mould the nasal tip, columella and alar rims. The permanent forehead defect can be covered with a retroauricular full-thickness skin graft. The temporary scalp defect is covered with a split skin graft or a non-adherent dressing, and pressure bandages are applied for 24 hours.

The second-stage procedure is performed 2-3 weeks later, by which time the flap has acquired a host blood supply. The pedicle is divided and inset, while the proximal end of the flap, which is surplus to requirement, is returned to its original donor site on the forehead. Additional support or lining of the nose can be used in conjunction with the Converse flap and may include septal composite grafts, bone or cartilage. ^4,7

In the Yemen the delay in presentation of basal cell carcinoma is probably due to a combination of ignorance of the potential seriousness of the lesion, misdiagnosis as primary infection and treatment with antibiotics, misplaced confidence in traditional remedies, fear of ‘western medicine’, and inability to take time off work or pay for medical attention. In most of the patients seen radiotherapy, even if available, would no longer have been an option. Even for smaller lesions the required regimen, entailing multiple visits to the hospital, might not be economically feasible. The choice is thus essentially limited to surgery. The use of tissue expanders in the forehead to create ‘extra skin’ for cover of the nasal defect has been well described for such cases, ⁸ but in this series was ruled out because of the high cost but also because of the required number of hospital visits and perceived higher infection rate. The scalping flap is an acceptable compromise between excision of tumour, reconstruction, aesthetics and patients' desire to return to their work and families.

The reliability and versatility of the Converse scalping flap can be explained in terms of the angiosomes involved. In 1987 Taylor and Palmer introduced the concept of dividing the body into angiosomes—three-dimensional anatomical blocks of tissue supplied by source arteries. ⁹ Houseman and Taylor used this new knowledge of territories of the superficial temporal and ophthalmic arteries to explain the differences in scalp and forehead flaps.¹⁰ They showed that, in the design of a flap, an adjacent vascular territory can safely be captured on the branches of one angiosome but that perfusion difficulties can arise when attempts are made on one or more successive territories. This explains why large local skin flaps can be raised successfully, in defiance of conventional ideas on length-to-breadth ratios. Whereas the Converse scalping flap is based primarily on the superficial temporal vessels on one side, avoids the ophthalmic territory on the same side and links with the contralateral ophthalmic or superficial temporal artery to produce a two-territory flap, McGregor's transverse forehead flap tries to capture three additional territories in succession, often with poor tip perfusion.

The scalping flap thus has several advantages over other options for nasal reconstruction. For all but the largest defects, skin for the permanent defect can be taken from the upper and lateral portion of the forehead, thus minimizing the visible scar. The donor defect can be covered with a full thickness skin graft from the retroauricular or supraclavicular region, which gives a good colour and texture match. Most of the incision is behind the hairline, and once the pedicle of the flap is divided at stage two, the hair-bearing scalp skin is returned, leaving scars mainly in hairy scalp.

Sixty years after it was first described, the Converse scalping flap still has a place in subtotal nasal reconstruction.