Protocols and complications in the reconstruction of major scalp defects
Condutas e intercorrências na reconstrução de grandes defeitos do couro cabeludo

INTRODUCTION

The outer table of the calvarium receives nutrition through the periosteum. Large scalp defects owing to trauma or neoplasms can endanger the vitality of the bones of the neurocranium, dura mater, and underlying brain. The loose connective tissue between aponeurotic galea/epicranium muscle and periosteum favors intracranial metastases, thrombi, and infections¹.

Large scalp defects are a major challenge for reconstruction, and in the absence of periosteum, these impair the use of skin grafts. Decortication of the outer table for skin grafting of the diploe provides aesthetically poor results, leading to fragility and susceptibility to malignancy. Romero et al., in 2018², published an algorithm recommending microsurgery for defects larger than 5 cm. Although vascular microsurgery provides the best results in the repair of large scalp defects³, it requires adequate team and resources. Souza, in 2012⁴, used local flaps and emphasized the importance of superficial temporal vessels in maintaining the viability of these flaps.

CASE REPORTS

CASE 1

A 69-year-old male patient with hypertension and diabetes underwent kidney transplant 17 years ago and regularly uses immunosuppressants. He had actinic keratoses on the face, scalp, and limbs, which were treated with cryotherapy and fluorouracil. In 2015, he had large moderately differentiated squamous cell carcinoma (SCC) with muscle invasion in the dorsum of the nose and was treated by excision and coverage using midline forehead flap. He had multiple and recurrent moderately differentiated multifocal SCC in the parietal regions (Figure 1).

Figure 1 - A: (Case 1) Recurrent squamous cell carcinomas in a renal transplant patient and defects after excision. B: (Case 1) Intraoperative period showing the anterior flap with later distal epidermolysis. C: (Case 1) Late postoperative appearance.

Figure 1 - A: (Case 1) Recurrent squamous cell carcinomas in a renal transplant patient and defects after excision. B: (Case 1) Intraoperative period showing the anterior flap with later distal epidermolysis. C: (Case 1) Late postoperative appearance.

CASE 2

A 68-year-old male, white patient with diabetes and rheumatoid arthritis regularly uses corticosteroids and methotrexate. He had multiple actinic keratoses on the bald scalp and was initially treated with cryotherapy. After 4 years, he returned with a recent, rapid-growth, infiltrate, vegetative, painful, ulcerated lesion in the frontoparietal region of the scalp measuring 4.5 x 4.0 x 1.5 cm. A biopsy revealed a well-differentiated, ulcerated SCC extending up to the hypodermis (Figure 2).

Figure 2 - A: (Case 2) Vegetating squamous cell carcinoma in an immunosuppressed patient and the defect after excision. B: (Case 2) Transoperative appearance: flap rotation and final aspect. C: (Case 2) Late postoperative appearance.

Figure 2 - A: (Case 2) Vegetating squamous cell carcinoma in an immunosuppressed patient and the defect after excision. B: (Case 2) Transoperative appearance: flap rotation and final aspect. C: (Case 2) Late postoperative appearance.

CASE 3

A 68-year-old male patient who underwent a liver transplant nine years ago and continuously uses immunosuppressants. He had a large vegetative lesion in the left parieto-occipital region. A biopsy revealed exophytic SCC (Figure 3).

Figure 3 - (Case 3) Squamous cell carcinoma in a renal transplant patient: initial lesion, deformity after excision, flap rotation, and final appearance.

Figure 3 - (Case 3) Squamous cell carcinoma in a renal transplant patient: initial lesion, deformity after excision, flap rotation, and final appearance.

CASE 4

An adult male patient who was struck with an ax seven years ago suffered head trauma. He was operated four times at Neurosurgery Services. For more than once, cranioplasty was performed with self-polymerizing acrylic, followed by subsequent infection and frontoparietal osteomyelitis, requiring the removal of the implant and new bone debridement (Figure 4).

Figure 4 - (Case 4) Sequelae of head trauma: frontoparietal bone loss with skin graft over the dura mater and fistula. Tissue expansion, cranioplasty, and immediate and late postoperative period.

Figure 4 - (Case 4) Sequelae of head trauma: frontoparietal bone loss with skin graft over the dura mater and fistula. Tissue expansion, cranioplasty, and immediate and late postoperative period.

At another service, he received partial skin graft placed directly on the remaining dura mater and the presumably performed galeal flap. Initial examinations revealed a frontoparietal defect, subdural clamps, and a clinically significant fistula draining serous material over the brain mass precariously protected by the graft. He had convulsive episodes after suffering minor trauma in the graft region during his work as a car mechanic.

DISCUSSION

The low elasticity, thickness of the skin and subcutaneous tissue, and presence of a thick aponeurotic galea on a convex surface make the reconstruction of large scalp defects a challenging task. Abundant anastomoses between the temporal, supraorbital, supratrochlear, posterior auricular and occipital vessels usually allow scalp flaps with only a small pedicle to survive and large flaps to recover without complications^5,6.

Most published cases of SCC have reported occurrence in the head and neck, with 8.3%–25.2% lesions occurring in the scalp. The current large numbers of living patients who underwent transplantation require more attention since immunosuppressants contribute to the formation of skin neoplasms.

The clinical recommendation for the margin of excision of SCC is 4 mm for low-risk patients and 6 mm for high-risk patients⁷. We use about 10 mm of margin based on the pathology, frequently removing the periosteum.

In case 1, local relapses and coalescence of premalignant lesions required a large excision. Although the large defect (16 x 16 cm) indicated the need for a microsurgical free flap, the chronic use of immunosuppressants, diabetes, and hypertension increases the risk of compromising the kidney transplanted 17 years ago in a longer surgery. We used two temporal-parietal-occipital rotation flaps for the reconstruction. The first, with a pedicle in the right temporal region, was rotated to cover the earliest portion of the defect. The second, lower and longer, with pedicle in the left temporal region, was rotated to occlude the posterior portion. The secondary occipital defect, with intact periosteum, received an inguinal total skin graft. In the postoperative period, epidermolysis and superficial necrosis occurred on the distal margin of the first flap. They were treated by debridement with hyaluronidase and outpatient cleaning, followed by dressings with Rifamycin and, finally, by colloidal occlusive dressings, showing excellent results.

Chronic use of methotrexate in patients with severe rheumatoid arthritis causes immunosuppression (case 2). After excision of the lesion, two randomized flaps were used: one larger and longer on the right with occipital pedicle, and one smaller on the left with temporal pedicle.

Distal suffering occurred in the flap on the right, leading to bone exposure and gap. With local anesthesia, a small flap of adjacent galea was rotated and sutured over the exposed bone. Using occlusive hydrocolloid dressings, epithelialization from the galea completely repaired the defect. This case illustrates the high safety of the pediculated flap in the temporal vessels and the high epithelization capacity of the galea.

Case 3, who underwent liver transplantation, received surgical treatment similar to case 2. But in this case, the right flap of the occipital pedicle was shorter, and there were no complications.

In case 4, temporal, frontal, and occipital scars limited the use of flaps. Tissue expansion was the option chosen in the absence of microsurgical resources in a local public hospital in the 1980s. This technique was recommended by Sasaki in 1985⁸, Anger in 1988⁹, and other authors¹⁰, followed by cranioplasty Korloff et al., 1973¹¹ and some osteosyntheses with steel wires. Despite the extrusion of one synthesis and a small bone fragment, it had no relapse of the fistula, with adequate protection to the brain and excellent aesthetic results. This case illustrates the use of an expanded advancement flap in the unpredictability of temporal flaps.

CONCLUSION

The experience gained in the surgical treatment of these complex and unusual cases indicates the preferred choice of random-pattern large fasciocutaneous flaps with temporal pedicles in the reconstruction of large scalp defects over microsurgery. Distal ischemic suffering may occur in these flaps, but when they are adequately treated, as in the cases presented, excellent aesthetic and functional results are achieved.