Application of Frontotemporal Expanded Flap with Bilateral Superficial temporal vessels in Repair of Large Area Scar Contracture in Face and Neck

Ming-chen SHAO,Peng CHENG,Yan-kui CUI

Jiaozuo Second People’s Hospital,Jiaozuo Ciry,Henan Province,456000，China

ABSTRACT Objective To summarize the clinical experience of frontotemporal expanded flap with bilateral superficial temporal vessels in repairing large area scar contracture in face and neck.Methods 14 patients with facial and Cervical scar contracture in our hospital were taken as the research object.With bilateral superficial temporal vessels as pedicles,a 400-600ml skin dilator was inserted into the forehead and 50-100ml skin dilator was inserted into the two temporal parts respectively.Within 3-4 months,the water injection volume reaches 2 times of the dilator volume.After maintaining for one month,skin flap transplantation was performed.The frontal flap was reserved for hairline reconstruction,and the flap was cut to cover the area after facial and Cervical scar release to reconstruct the jaw-neck angle.The pedicle division and pedicle trimming were performed 3-4 weeks after operation.Results All the 14 patients completed the operation successfully.The flap expansion time is 5-6 months.The expanded skin flap covers an area of 26 cm×9 cm-42 cm×16 cm,and all the skin flaps survived after operation.Among them,2 patients suffered from flap congestion after flap transplantation.Follow-up for 6-12 months showed that the color and texture of the skin flap were similar to those of facial skin,with natural transition and no obvious bloating.The angle between the lower jaw and the neck is about 90.The anterior flexion,posterior extension,lateral flexion and rotation of the neck are obviously improved compared with the anterior,and the posterior extension is close to normal.Conclusion Frontotemporal expanded flap with bilateral superficial temporal vessels is suitable for patients with large-area scar contracture in face and neck that cannot be repaired after expansion of adjacent local normal tissues.

KEY WORDS Expanded skin flap; Frontotemporal region; Face and neck; Scar contracture; Large area;Superficial temporal vessels

Scar contracture of face and neck is a common sequelae of burns,which not only affects the facial functions and neck movement of patients,causing facial defects,but also affects the normal life and communication of patients to a certain extent,causing psychological burden to patients.The repair of facial and Cervical scar contracture should not only consider the improvement of function,but also try to ensure the beauty of appearance[1,2].The island flap with superficial temporal artery as blood supply source to repair facial soft tissue defects has the characteristics of similar color,texture and natural transition[3].The scar area of facial and Cervical scar contracture is often large,and it is difficult to repair it directly with skin flap.In this study,14 patients with facial and Cervical scar contracture were retrospectively analyzed by using frontotemporal expanded flaps with bilateral superficial temporal vessels.The report is as follows.

PATIENTS AND METHODS

General information

This group of patients came from 14 patients with facial and Cervical scar contracture admitted to our hospital from January 2010 to December 2018,all of whom were scar formation after burns,including 13 males and 1 female,aged 18-56 years,with an average age of 27.6 years.The average time from surgery to burn is 3.7 years,ranging from 12 months to 10 years.All patients suffered from scar involvement in face and neck,chin,neck and chest adhesion to varying degrees,and neck movement was obviously limited.All patients signed informed consent forms before operation.

Methods the operation was carried out in three stages

Skin dilator implantation.The patient takes the supine position.The doppler ultrasound blood flow detector was used to explore the position and course of frontal branch and parietal branch of superficial temporal artery in patients.The methylene blue meter was used to measure the embedding position and cavity range of the dilator.The anterior part is 1cm to the superior orbital edge,both sides are to the temporal hairline,and the posterior part of male patients is to the top of the head.After general anesthesia,the operation began.A length of 4-5cm was made at 1cm of the mark line at the posterior edge of the top of the head.Skin and subcutaneous tissue were cut successively,cap aponeurosis layer was peeled off,and blunt separation was carried out with bending shear.The frontal part should be separated under the frontal muscle.The temporal partial separation should be carried out between the deep temporal fascia and the temporal muscle.Separate boundary to methylene blue mark range.According to the defect that needs to be repaired after scar release,the flap area is calculated,and the appropriate cylindrical skin dilator is selected.A 400-600mL cylindrical skin dilator was placed on the frontal top of bilateral involved patients,and a 50-100mL cylindrical skin dilator was placed on the bilateral temporal parts.If the scar area at and below the neck is large,another 1-2 dilators can be embedded in the superficial layer of the deep fascia at the edge of the neck and chest scar.Place negative pressure drainage device,pull it out 3-4 days after operation,and start water injection after removing stitches 9-11 days after operation.Once a week,the amount of water injected each time is 10%-15% of the dilator volume.If the patient is obviously unwell or the skin flap turns white,the water injection interval can be prolonged by 1 week.The water injection period is 4-5 months,the total amount of water injection can reach up to twice the capacity of the dilator,and the expansion can be maintained for 1 month after reaching the ideal capacity.

Skin flap transplantation Before the operation,the frontal branch and parietal branch of superficial temporal artery were marked with the Doppler ultrasound vascular detector.CT angiography is feasible for patients with unsatisfactory Doppler ultrasound imaging effect.Methylene blue was used to mark the flap area.The pedicle of the flap included the frontal branch and part of the parietal branch of the superficial temporal artery.General anesthesia was used in the operation,and the skin flap was cut according to the preoperative design.According to the width of the patient's hairline before operation,a new hairline was marked 5-7cm from the superior orbital edge on the expanded skin flap,and the dilator was removed by incision here.The frontotemporal flap was formed by transverse incision of the skin flap at the top of the head,and the surrounding hyperplastic bone and fibrous connective tissue were removed with bone chisel.The width of frontal flap is suitable for direct suture of donor site.The pedicle of the flap is generally 2-3cm,which is covered and fixed with scar skin to protect the pedicle.If the width of the pedicle reaches 6-7cm,a skin tube can be formed.Fully release scar tissue of face and neck so that the head can be fully tilted back.The contracture platysma muscle is transversely cut at the horizontal position of the hyoid bone and separated to the surface of the hyoid bone to form a new jaw-neck angle.When the skin flap is transferred to the defect wound surface,if the area is insufficient,it can be repaired jointly by thoracic expanded skin flap.It is used for carrying out covered wound repair.After hand surgery,attention should be paid to keeping the donor and recipient areas warm,observing the blood supply of skin flap,and preventing infection with conventional antibiotics.

Pedicle cutting and flap trimming were performed 3-4 weeks after flap transfer.Before the pedicle is broken,pedicle breaking training can be carried out.According to the scar situation around the pedicle,the disconnection position is determined,the scar skin temporarily covered by the temporal donor site is removed,the pedicle is trimmed,the remaining pedicle is reduced and sutured to the temporal part,and the sideburns are repaired by reconstruction.One month after the operation,laser depilation can be performed on the flap part once a month,and it takes generally 4 times to basically remove hair.

RESULTS

All 14 patients in this group successfully completed the operation.The flap expansion time was 5-6 months.The area of expanded skin flap was 26 cm×9 cm-42cm×16 cm.All the flaps survived after the operation.Among them,2 patients had skin flap congestion,dark purple and obvious swelling after skin flap transplantation,and gradually returned to normal after one week of acupuncture bloodletting and massage.Flap thinning and fat removal were performed on 7 patients with overstaffed skin flap.Six patients underwent laser depilation after operation.Follow-up for 6-12 months showed that the color and texture of the skin flap were similar to those of facial skin,with natural transition and no obvious bloating.The jawneck angle was about 90°.The anterior flexion,posterior extension,lateral flexion and rotation of the neck are obviously improved compared with the anterior,and the posterior extension is close to normal.The donor site suture incision is hidden,scar is not obvious,and head hair grows normally.

DISCUSSION

The scar area of the face and neck is generally at a relatively forward position.In the past,autologous skin graft and free skin flap were mostly used for repair.Among them,skin graft has good short-term effect and no bloating,but its color is obviously different from that of adjacent skin,which is not conducive to beauty.In the later stage,skin contracture will still limit neck mobility [4].The survival conditions of free skin flap are harsh,and the tissue is generally thick,bloated and unnatural.If this is to be improved,multiple thinning operations must be carried out in the later period[5].Skin soft tissue expansion is a surgical technique that uses the skin expansion ability to increase the skin area.Through expansion,enough thinner skin flaps conforming to the appearance characteristics can be obtained,thus meeting the repair requirements of large-area scars.

In this study,frontotemporal expanded flap was designed to repair facial and Cervical scar contracture.The main blood supply of the flap comes from the superficial temporal artery and its frontal and parietal branches[6].The superficial temporal artery originates from the external carotid artery,separates from the mandibular neck,passes through the parotid gland body,and extends from the superficial layer of the root of zygomatic arch to the subcutaneous layer.Its position is shallow,running between superficial temporal fascia and subcutaneous.The superficial temporal fascia generally branches 2-4 cm above the zygomatic arch,i.e.Frontal branch and parietal branch.The frontal branch further branches out the frontal parietal branch and the frontal orbital branch,and moves backward and upward and anterior and downward respectively.The superficial temporal vein and its branches are accompanied by the superficial temporal artery and its branches,which are 2cm apart and slightly thicker than the arteries of the same name[7].At the zygomatic arch level,the superficial temporal vein is located behind the superficial temporal artery,and its end is injected into the posterior mandibular vein.

The skin flap with superficial temporal artery as blood supply source can take various forms.Hou Hexian et al.[8]used superficial temporal artery frontal branch island flap combined with neck expanded flap to repair cheek scar contracture patients with lower eyelid ectropion and mouth angle displacement.The maximum cutting area is 13.0cm×6cm,and the minimum area is 10.0 cm×3.0cm.All flaps survived after operation.Li Yangqun et al.[9]implanted superficial temporal vessels under the skin of cervical expanded flap.After 3 months of expansion,a cervical prefabricated flap pedicled with superficial temporal vessels was formed.The maximum area of the obtained flap is 12 cm×8 cm,and the pedicle length is 7-8 cm.Facial soft tissue defects was repaired,which achieved good results.

The flap area pedicled with unilateral superficial temporal vessels should not be too large.Some scholars[10]applied frontal expanded skin flap to treat hemifacial scar contracture deformity.After direct repair,obvious distal venous reflux disorder occurred.However,facial arteriovenous anastomosis with superficial temporal arteriovenous anastomosis can ensure good survival of the flap.In this study,patients need to repair Cervical scars,so this method is not suitable for repair.Instead,frontotemporal flap pedicled with bilateral superficial temporal vessels was used for repair.Double pedicle method has been practiced clinically.Yu Xiaobo et al.[11]reported the application of double pedicled frontal expanded flap to repair cervical scar contracture deformity.The method is to embed a 300-400ml dilator in the forehead,and the maximum area of the skin flap obtained is 28cm×12cm,and the cervical mobility is obviously improved after transplantation.Huang Yongxin et al.[12]used the same method to obtain axial flap with an area of 25cm×6cm-33cm×16cm,which was used to repair mandibular scar and achieved good results.The double pedicle flap method adopted in this study is to add the temporal expanded flap to the frontal expanded flap,and the obtained flap has a larger area,with the maximum area being 42cm×16 cm.The expanded tempora flap not only increases the width of the pedicle of the flap,but also can be used to repair scars in the preauricular region and cheek region,ensuring tension-free suture between the pedicle and donor tissue and reducing secondary deformities after repair.

The surgical experience and experience are as follows:(1)Superficial temporal vessels must be accurately located before operation,which can be detected by the Doppler ultrasound.When necessary,CA angiography can be used to determine vascular distortion[13].(2)Frontal dilator can stimulate the proliferation of surrounding skull bone and fibrous connective tissue.The bone chisel should be used to remove it as much as possible to avoid obvious protrusion of forehead after operation,which affects the appearance.(3)Male patients can carry part of the front hairline for heavy beard reconstruction; female patients should try not to remove or cut less hairline endothelial flap.(4)When the remaining expanded frontal flap is sutured with hairline suture,partial modification should be made for those with poor incision alignment to avoid postoperative scar adhesion[14].(5)Cervical scar contracture often involves platysma muscle and anterior cervical muscle group.It must be released to the hyoid surface to completely expose the jaw-neck angle.(6)Low tension suture should be applied to the skin flap and the donor site,and elastic sleeve should be used for compression bandaging after operation,thus reducing the probability of venous reflux disorder of largearea skin flap[15].(7)The skin incision at the sideburns of the skin flap should not be too large.Generally,it should be controlled within 3cm to ensure the closure of the incision.(8)Wear neck brace after operation and strengthen functional exercise to prevent scar recurrence.Evaluation of surgical methods:The superficial temporal vessels and their branches have thick diameters,long vascular pedicles,abundant blood supply,easy flap cutting and large repairable range,but the risk of venous reflux disorder after operation is high,which should be paid attention to.This operation is suitable for those who cannot be repaired after normal tissue expansion in adjacent areas.The operation was carried out in three phases.The patients were hospitalized for a long time and the discomfort of the flap dilator was obvious.Patients must have sufficient psychological preparation.The amount of surgery is large,and there are many modified operations after repair,and the requirements for doctors are high.It is recommended to be performed by experienced doctors in facial surgery.