Anteriorly based pericranial flap: an anatomic study of feeding arteries

Three-Dimensional Computed Tomographic Study of the Supratrochlear Artery and Supraorbital Artery to Determine Arterial Variations and Their Relationship

BACKGROUND

The forehead has high risks associated with filler injection considering its highly complex vascular system. This study aims to thoroughly describe the anatomical variations and relationships between the supratrochlear artery (STA) and supraorbital artery (SOA).

MATERIALS AND METHODS

We studied 56 cadaveric heads by computed tomography after contrast-agent injection.

RESULTS

The deep branch of the STA originated in the deep superior orbital arcade and the ophthalmic artery (OA), whereas that of the SOA originated at 3 locations: the deep superior orbital arcade, deep superior orbital artery, and OA. The superficial branch of the STA also had 3 origins: the superficial superior orbital arcade, OA, and angular artery, whereas the superficial branch of the SOA had 2 origins: the superficial superior orbital arcade and OA. Based on the relationship between the STA and SOA, 2 main arterial distribution patterns were observed in both superficial and deep layer arteries: STA/SOA connected pattern and STA/SOA disconnected pattern, of which the latter pattern has 3 subtypes.

CONCLUSION

The forehead arteries have complex origins. The relationship of the supratrochlear and supraorbital arteries could be categorized into 2 main patterns. The study elucidated the complexity of the forehead vasculature.

Obliteration and Contouring of Comminuted Anterior Wall Frontal Sinus Fracture Using Pericranial Flaps

One of the common postoperative complications of comminuted fractures of frontal sinus are contour deformity, hardware extrusion, adherence and/or palpability, and skin thinning. We are presenting our novel technique with pericranial flaps to decrease these complications. The study was performed from January 2019 to January 2020, on 40 cases of comminuted fractures of anterior wall of frontal sinus, 28 men and 12 women, with an average age of 41 years. Injury resulted from motor vehicle crashes (n = 25), motorcycle crashes (n = 11), and falling from heights (n = 4). Our novel technique involves the use of two anteriorly based pericranial flaps; one flap is used for obliteration of the frontal sinus and the other is used to overlay the hardware used to restore forehead contouring and to eliminate the possibility of early extrusion or late plates or mesh palpability. Two patients had postoperative minimal disruption of forehead lacerations healed with secondary intention and minimal scarring. Excellent patient compliance without any complaint of mesh palpability. No adherence occurred and no skin thinning. This technique (two anteriorly based pericranial flaps) may be more reliable to obliterate the frontal sinus also overlaying the hardware used to improve forehead contour and decrease the incidence of mesh palpability and skin adherence than using hardware without flap coverage.

The Transorbital Pericranial Flap

OBJECTIVE

The objective of the present study was to describe and evaluate the feasibility, mobility, and surface area provided by the simple and extended transorbital pericranial flap (TOPF). Furthermore, we compared this novel technique with the current practice of pericranial flap harvesting and insetting techniques. We also studied the adequacy of the TOPF in the reconstruction of postoperative anterior cranial fossa (ACF) defects.

METHODS

The TOPF was performed bilaterally in 5 alcohol-preserved, latex-injected human cadaveric specimens. The TOPF was harvested in 2 stages: the orbitonasal stage and the cranial stage. For the orbitonasal stage, a transorbital superior eyelid approach was used. We have described 2 harvesting techniques for creating 2 distinct TOPF types (simple and extended) according to the main vascular pedicle. The superficial flap areas offered by the simple and extended TOPF and the traditional bicoronal pericranial flap were calculated and compared. The distances from the supratrochlear and supraorbital arteries to specified anatomical landmarks were also measured. Additionally, the ACF defect area of relevant surgical cases performed using endoscopic transcribriform approaches were measured on immediate postoperative computed tomography head scans using radiological imaging software.

RESULTS

The harvest of both the simple and the extended TOPFs was efficient. As expected, the areas offered by simple and extended TOPFs were smaller than that offered by the traditional bicoronal flap. However, the surface area offered by either the simple or extended TOPF provides sufficient coverage for most ACF defects. A high spatial distribution was observed between the vascular pedicles and their respective foramen or notch.

CONCLUSIONS

The TOPF represents a novel harvesting, tunneling, and insetting technique that offers a large, versatile, pedicled flap for coverage of most standard ACF defects after endoscopic surgery.

Modification of Periosteal Flap as Management of Cerebrospinal Fluid Leakage after Frontal Sinus Fracture Surgery in Moderate Traumatic Brain Injury Patients

Main management for the frontal sinus fracture is using the pericranial flap. Pericranial flaps based on the supraorbital and supratrochlear vasculature have previously been used with significant success for the separation of intracranial and extracranial spaces after major trauma. Defect closure was modified due to lack of the frontal periosteum; the graft was made from the temporal side of periosteum to make primary periosteal flap longer. Defect closure could be optimum. Evaluation for 6 months showed a significant improvement without major complications. In this article, we propose a new modification technique as one of promising alternatives.

Localization and Topography of the Arteries on the Middle Forehead Region for Eluding Complications Following Forehead Augmentation: Conventional Cadaveric Dissection and Ultrasonography Investigation

Forehead augmentation with filler injection is one of the most dangerous procedures associated with iatrogenic intravascular injection resulting in the severe complications. Nonetheless, few studies have determined the explicit arterial localization and topography related to the facial soft tissues and landmarks. Therefore, this study aimed to determine an arterial distribution and topography on the middle forehead region correlated with facial landmarks to grant an appropriate guideline for enhancing the safety of injection. Nineteen Thai embalmed cadavers were discovered with conventional dissection and 14 Thai healthy volunteers were investigated with ultrasonographic examination on the middle forehead. This study found that at the level of mid-frontal depression point, the transverse distance from the medial canthal vertical line to the superficial and deep branches of supraorbital artery were 9.1 mm and 15.1 mm, respectively. Whereas the depths from the skin of these arteries were 4.1 mm and 4.3 mm, respectively. Furthermore, the frontal branch of superficial temporal artery was detectable in 42.1% as an artery entering the forehead area. At the level of lateral canthal vertical line, the vertical distance of frontal branch was 31.6 mm, and the depth from skin of the artery was 2.7 mm. In conclusion, a proper injection technique could be performed based on an intensive arterial distribution and topography, and ultrasonographic examination before the injection is also suggested in order to restrict the opportunity of severe complications.

Reliability of and indications for pericranial flaps in anterior skull base reconstruction

Owing to changes in the treatment of skull-base tumors, such as perioperative radiotherapy and advances in approaching the skull base, the use of pericranial flaps should be reconsidered. Therefore, we reviewed the reliability of and indications for pericranial flaps in 26 cases in terms of patient background, the effects of preoperative and postoperative treatment, and the pattern of blood circulation. Flaps were harvested as 25 anteriorly based and 4 laterally based. As a result, postoperative complications were observed in 4 patients. No other risk factors, except for heavy smoking, were observed relative to patient background. Sixteen patients had perioperative radiotherapy, and complication rate was significantly higher in patients with preoperative radiotherapy than patients without preoperative radiotherapy (P=0.014). However, no complications, such as cerebral spinal fluid leakage and intracranial infection, were observed in patients receiving postoperative radiotherapy. Laterally based pericranial flaps had a high complication rate (25%), but it was not significantly higher than anteriorly based flaps (P=0.467). Five anteriorly based flaps were harvested with less feeding vessels as usual because of applying dismasking flap approach, but it did not lead to increasing in complication rate. We conclude that a pericranial flap can be used for skull base reconstruction even if postoperative radiotherapy is planned but might be avoided for patients who have received preoperative radiotherapy. In addition, particular care and flap design should be taken to preserve sufficient vascularity when pericranial flaps are raised as laterally based and less feeding vessels as usual.

Use of pericranial flaps in the management of cranial base trauma

Pericranial flaps based on the musuloaponeurotic or myofacial layers of the scalp have great utility in the management of acquired and congenital craniofacial deformities. Their use in traumatic deformities is indicated in the presence of craniopharyngeal communications and significant anterior cranial fossa dead space created from frontal sinus obliteration. The indications and operative techniques and the results of the use of these flaps in 10 consecutive patient with extensive cranial base trauma are presented.

Laser-Doppler examination of the blood supply in pericranial flaps

PURPOSE

The purpose of this investigation was to determine if there is evidence suggestive of blood flow within pericranial flaps.

PATIENTS AND METHODS

An index of blood flow using laser-Doppler blood flowmetry was obtained in pericranial flaps from 10 patients who were undergoing a coronal flap for reconstructive procedures. The data were analyzed using fast Fourier transformation to indicate the presence or absence of blood flow.

RESULTS

All but 1 pericranial flap showed evidence of blood flow within. Most flaps had blood flow even several centimeters distal to the origin of the flaps' pedicles.

CONCLUSION

The data clearly indicate that pericranial flaps contain at least some blood flow. However, the quantity of blood flow could not be assessed using this technology.

Utility of the pericranial flap in frontal sinus and anterior cranial fossa trauma

Complex injuries to the frontal bar of the upper face can cause significant damage to the anterior cranial fossa. One of the biggest challenges in the repair of such injuries is the prevention of a cerebrospinal fluid leak and separation of the brain from the nasal cavity. Although many autogenous and alloplastic materials can be used for this purpose, the pericranial flap offers a viable alternative. This axially based flap is readily available, does not require an extra harvest site, and can be fashioned appropriately to obliterate the frontal sinus and/or line the anterior cranial base to decrease the possibility of cerebrospinal fluid leaks. The authors' experience with this flap in complex frontal sinus and anterior cranial fossa injuries is described.

Vascular Anatomy of the Anteriorly Based Pericranial Flap

OBJECTIVE:

The purpose of this study was to examine the vascular supply of the anteriorly based frontal pericranial flap to determine whether separating the pericranium from the galea above the orbital rim would devascularize the pericranial flap.

METHODS:

The arteries supplying and the veins draining the frontal pericranial flap were examined in 17 adult cadavers using ×3 to ×30 magnification. The arteries were examined on 25 sides and the veins on 16 sides.

RESULTS:

The main trunk and superficial branches of the supraorbital and supratrochlear arteries, which course in the galea-frontalis muscle layer, give rise to the deep branches that supply the pericranium. These pericranial branches may arise in the orbit or at the level of or above the orbital rim. Pericranial arteries that arose above the level of the orbital rim and would be divided in separating the galea and pericranium were found in 28% of the sides examined. Pericranial veins that coursed above the orbital rim and would be divided in separating the galea-frontalis muscle layer from the pericranial layer were found in 43.8% of the sides examined.

CONCLUSION:

In preparing a pericranial flap based anteriorly on the supraorbital rim, the separation of the galea-frontalis muscle layer from the pericranium layer should not extend into the 10 mm above the supraorbital rim if the arterial and venous pedicle of the pericranial flap is to be preserved.

The use of multifolded pericranial flaps as "plugs" and "pads"

Pericranial flaps are thin and, hence, their volumes are small. Therefore, their use for soft-tissue augmentation has not been popular. In this article, the author introduces a new concept: the use of a multifolded pericranial flap as a "plug" or a "pad" for localized contour defects. Eight patients were included in the study. In all cases, an anteriorly based pericranial flap was used, and the flap was folded on itself several times to increase its bulk. The results were satisfactory in all patients. The literature on the topic is reviewed, and the blood supply of pericranial flaps is discussed.

Surgical approach to midline skull base tumors with olfactory preservation

Through the frontal approach, a skull base tumor in the deep midline region is obscured by the cribriform plate. This paper demonstrates our experience of operating on seven patients with midline skull base tumors posterior to the cribriform plate using a technique of maintaining the olfactory-cribriform anatomy. Following a bifrontal craniotomy and an orbitonaso-glabellar osteotomy, a circumferential osteotomy of the cribriform plate and horizontal incision of the nasal mucosa permitted mobilization of the cribriform plate unit along with the frontal lobe, providing a wide exposure of the posterior midline area. Tumors were resected from the posterior nasopharynx, ethmoid sinus, sphenoid sinus, and upper portion of the clivus. The skull base defects were repaired with the bipedicled temporoparietal galeal flap. Two patients lost olfaction because of poor preservation of the nasal mucosa and intradural dissection of the olfactory bulb. Five patients showed complete recovery of olfaction in 8 weeks. None of the patients developed cerebrospinal fluid leakage, infection, or increased neurologic deficits. En bloc mobilization of the cribriform plate and the bipedicled temporoparietal galeal flap are very useful for the management of midline cranial base tumors posterior to the cribriform plate as long as the olfactory unit is not involved with tumors.

Galeo-pericranial flaps in the forehead: a study of blood supply and volumes

Despite their extensive use in anterior cranial base reconstruction, very little is understood about the blood supply of galeo-pericranial flaps derived from the forehead region. The goal of this study was to define the extent of the reliable axial blood supply and to determine the volumes of these flaps. The blood supply to anteriorly based galeo-pericranial flaps depends entirely upon the deep branches and a variable component of the superficial branches of the supraorbital and the supratrochlear vessels. The axial component of the blood supply to these flaps is 20-70 mm. The extent of "random' pattern blood supply distal to this could not be adequately assessed. The volumes of various galeo-pericranial flaps range from 3 to 48 cc. The well vascularized proximal portions of galeo-pericranial flaps may well serve the reconstructive needs of the anterior cranial base. Use of more distal portions of these flaps should be undertaken with caution. Some increase in bulk and vascularity may be achieved if the pericranial and the galeal-frontalis myofascial flaps are harvested as a single unit, the composite galeal-frontalis-pericranial flap. Due to the vascular and volume limitations of galeo-pericranial flaps, consideration should be given to the use of microvascular free tissue transfers in instances where large soft tissue defects and a large "dead space' occur.

Vascular anatomy of the galeal occipitalis flap: a cadaver study

The vascular anatomy of the galeal occipitalis flap was studied in 10 fresh cadavers by an intraarterial dye injection technique. The scalp flap was based posteriorly, incorporating both the occipital and posterior auricular arteries. A good transmidline anastomosis was demonstrated between the two occipital arteries in the full-thickness scalp flap. However, in the isolated galeal flap, although the axial distribution of the occipital artery was maintained, fewer transmidline connections were seen between the two occipital arteries. The posterior auricular artery was consistently visualized in all dissections, and it showed good connections with the ipsilateral occipital artery. However, there were very few anastomoses between the two posterior auricular arteries across the midline. The rich anastomotic network between the occipital artery and the posterior auricular artery extended well beyond the vertex. This study showed that a large flap can be raised if both the occipital artery and the posterior auricular artery are included in its base. The occipital artery is a vessel of satisfactory size and is potentially a good vascular source for a thin galeal free flap. It is recommended that the flap be raised at the subperiosteal level for ease of dissection and protection of the vessels, which are initially in the subgaleal plane and then arborize in the galea.

Reconstruction of the anterior cranial base with the galeal frontalis myofascial flap and the vascularized outer table calvarial bone graft

Reconstruction of the anterior cranial base after tumor extirpation must seal off the cranial cavity from the upper respiratory tract. The key to success is to use vascularized materials for the structural support of the brain. From October 1989 to July 1992, 10 patients underwent anterior cranial base reconstruction after basicranial tumor resection; the lesions were four meningiomas and six malignant tumors of the ethmoid, maxilla, and orbit. The malignant tumors included four recurrent tumors that had been previously treated by a transfacial approach. After tumor extirpation, the resultant bony defects in the anterior cranial base, involving the orbital roof as well as the cribriform plate, ranged from 4 x 3 to 6 x 7 cm in size. The materials used in reconstruction were the galeal frontalis myofascial flap and the outer table calvarial bone flap, which is based on the temporoparietal galeal flap. Both materials are known to have rich blood supplies. These flaps make a reliable separation between the cranial cavity and the respiratory tract in three layers: the galeal frontalis myofascial flap, the vascularized calvarial bone, and the temporoparietal galea. Postoperative complications included one subcutaneous hematoma and one temporary cerebrospinal fluid rhinorrhea. We think this reconstructive technique will be useful in selected circumstances, especially after resection of a recurrent malignant tumor.