The use of free flaps in skull base reconstruction

Reconstruction of Large Tissue Defects After the Resection of Brain Tumors Using a Skin Flap With Vascular Pedicle

The reconstruction of large tissue defects after the resection of brain tumors is challenging for every neurosurgeon. The authors describe the benefits of a skin flap with vascular pedicle in the reconstruction of large tissue defects after the resection of brain tumors. In this retrospective analysis, a skin flap with vascular pedicle reconstruction was used in 5 patients who underwent intracranial tumor resection, accompanied by tissue defects, cerebrospinal fluid leakage and scalp infection. The surgical techniques are described, and the outcomes were discussed. The harvested flaps showed well-vascularized healing of the transplanted skin without partial necrosis in all 5 patients. One patient had cerebrospinal rhinorrhea, which was successfully treated by endoscopic repair. Another patient had cerebrospinal fluid leakage, which was successfully treated by continuous lumbar drainage. A skin flap with vascular pedicle is an effective choice for the reconstruction of large tissue defects after the resection of brain tumors.

When is a multidisciplinary surgical approach required in sinonasal tumours with cranial involvement?

The term “sinonasal tumours” includes a large spectrum of diseases, which are characterized by heterogeneous biological behavior and prognosis, and located in a critical anatomic area. Diagnosis and treatment of sinonasal tumours require the contribution of different disciplines. A narrative review was performed to highlight the role of surgeons in contributing to a multidisciplinary approach to sinonasal tumours. Diagnosis and staging of sinonasal tumours is challenging and requires collaboration between surgeons, radiologists, and pathologists. The identification and management of critical extensions (orbital or intracranial encroachment, vascular abutment or encasement) is fundamental for successful treatment. Most cases of advanced sinonasal tumours can undergo surgical intervention by an adequately trained otorhinolaryngological team. The contribution of neurosurgeons and oculoplastic surgeons is required in selected scenarios. In rare circumstances, multidisciplinary reconstructive strategies can be indicated for complex tissue defects. Furthermore, a multidisciplinary approach is pivotal in the management of perioperative complications. While surgery remains the mainstay of treatment, the role of non-surgical adjuvant or even exclusive treatments is constantly expanding.

Role of craniofacial surgery in oral and maxillofacial tumors involving the skull base: A retrospective analysis of 126 patients

OBJECTIVES

Oral and maxillofacial tumors involving the skull base (SB) are rare and complex, making treatment difficult and controversial. The purpose of the present study was to evaluate the treatment efficacy of craniofacial surgery (CFS).

STUDY DESIGN

Patients who underwent CFS for these tumors between May 2000 and November 2017 were retrospectively analyzed. Clinicopathologic and treatment modality data were collected and follow-up was recorded. Kaplan-Meier and log-rank tests and Cox-regression model were used for survival analysis.

RESULTS

In total, 126 patients were enrolled (70 males and 56 females; 97 malignant tumors). Squamous cell carcinoma accounted for the majority of tumors. The lip-submandibular-neck approach was most frequently applied. Through-and-through SB bone or partial dura resection was performed in 42 cases. A pathologic positive margin was found in 18 cases. Of the included patients, 80 underwent simultaneous craniofacial reconstruction. The postoperative complications rate was 11.1%. Estimated 1-year, 3-year, and 5-year overall survival rates were 78.8%, 68.2%, and 54.4% respectively; and the 1-year, 3-year, and 5-year recurrence-free survival rates were 77.4%, 66.8%, and 63.8%, respectively. Multivariate analysis indicated postoperative complications, radiotherapy, recurrence, and metastasis status had a negative impact on survival (P < .05).

CONCLUSIONS

Although tumors involving the SB had various clinicopathologic characteristics, with interdisciplinary cooperation, CFS is an optimal option.

Free tissue reconstruction of the anterior skull base: A review

Objective

There has been a significant shift from open craniofacial resection of the anterior skull base to endoscopic approaches that accomplish the same outcomes in tumor ablation. However, when open resection is required, free flap reconstruction is often necessary to provide sufficient well-vascularized tissue for optimal wound healing as well as providing adequate tissue bulk for cosmesis. This articleaims to providea focused review of free flaps most commonly used in anterior skull base reconstruction.

Methods

This is a state-of-the-art review based on expert opinion and previously published reviews and journal articles, queried using PubMed and Google Scholar.

Results & conclusion

Anterior skull base reconstruction via free tissue transfer is imperative in limiting complications and promoting healing, particularly with large defects, post-radiation, and in at-risk patients. The type of free flap utilized for a particular anterior skull base reconstruction should be tailored to the patient and nature of the disease. This review offers insight into the numerous reconstructive options for the free flap surgeon.

Management of sinonasal adenocarcinomas with anterior skull base extension

INTRODUCTION

Sinonasal adenocarcinomas (SNAC) are rare and heterogeneous. Management of SNAC follows a rather standardized and internationally accepted paradigm. Several refinements have been introduced during the last decade.

METHODS

A narrative review of most updated literature on SNACs has been conducted.

RESULTS

SNACs are classified as intestinal-type and non-intestinal-type, which are further categorized according to grade. Preoperative work-up should include magnetic resonance imaging (or contrast-enhanced computed tomography as a secondary or complementary choice) and biopsy under general anesthesia, or under local anesthesia in case of a history of exposure to wood and/or leather dust. Positron emission tomography, neck ultrasound, and fine-needle aspiration cytology are indicated in selected cases. Surgery represents the most common upfront modality of treatment and is usually accomplished via a transnasal endoscopic approach. Adjuvant radiation therapy is indicated for high-grade, locally advanced tumors and/or in case of margins involvement. Neoadjuvant chemotherapy with cisplatin, 5-fluorouracil and leucovorin may offer high response rates and long-term control in a subgroup of patients affected by intestinal-type adenocarcinoma, and in particular in those whose tumors harbor a functional p53 protein. Most of the bio- and immune-therapeutic potentials on SNACs still remain theoretical, and no clinical data are currently available.

CONCLUSIONS

Management of SNAC consists of histological diagnosis, radiological staging, radical surgery, and adjuvant radiation therapy. Neoadjuvant chemotherapy can be indicated in selected cases. The role of biotherapy and immune therapy still needs to be elucidated.

Side-Door Temporoparietal Fascia Flap: A Novel Strategy for Anterior Skull Base Reconstruction

BACKGROUND

The armamentarium for anterior skull base (ASB) reconstruction includes a variegate spectrum of grafts, endonasal pedicled flaps, regional pedicled flaps, and free flaps, which are selected to face specific scenarios. The use of a vascularized flap in case of large ABS defects ensures an adequate blood supply. The aim of this study was to evaluate the possible role of temporoparietal fascia flap (TPFF) in ASB reconstruction.

METHODS

Eight fresh-frozen head specimens were dissected to evaluate the adequacy of TPFF and pericranial flap (PF) for the reconstruction of ASB defects. The percentage of coverage of the ASB was calculated for TPFF and PF. An anatomic-radiologic analysis was performed to provide useful practical information for flap harvesting and positioning.

RESULTS

The TPFF was easily transposed to the ABS defect through an epidural corridor; the edges of the TPFF were successfully placed in the intradural space, in the epidural space, or on the extracranial surface of the ABS defect. The PF was particularly adequate for median defects, and the TPFF was shown to be useful also in cases with paramedian-supraorbital extension. The median percentage of coverage of the ASB was significantly higher for TPFF (85.1%) than PF (65.7%) (P = 0.018).

CONCLUSIONS

The supraorbital epidural corridor is a possible novel pathway for transposition of the TPFF for ASB reconstruction. Side-door TPFF was shown to be an ideal choice for large ASB defect with lateral supraorbital extension and could be useful in the scenario of salvage reconstruction for recurrent ABS cerebrospinal fluid leak.

Technique for reconstruction of large clival defects through an endoscopic-assisted tunneled retropharyngeal approach

BACKGROUND

Reconstruction of the clivus and posterior cranial base defects following endoscopic skull-base surgery can be particularly challenging. Commonly, defects in this region are repaired with pedicled mucoperichondrial flaps from the sinonasal cavity. Complex and large defects often require regional or free flaps, particularly when intranasal flaps have been exhausted. While there are no primary barriers to routing flaps into the clivus or nasopharynx in large open approaches, secondary surgical corridors are necessary during endoscopic cases for routing of free flaps. Routing of free-flap pedicles for endoscopic cranial base reconstruction has been described through secondary surgical corridors created through the maxillary sinus and infratemporal fossa. Here we describe the technique of a more direct pedicle route to the clivus through the retropharyngeal space.

METHODS

A patient with frank cerebrospinal fluid (CSF) rhinorrhea and extensive osteoradionecrosis of the clivus and craniocervical junction presented for treatment. Due to the size and location of the defect and previous exhaustion of candidate mucoperichondrial flaps, free-flap reconstruction was performed. A radial forearm free flap was tunneled through the prevertebral space into the nasopharynx and clivus and inserted with endoscopic-assisted techniques. The flap pedicle coursed through the retropharyngeal space to the neck vessels where arterial and venous anastomosis was established.

RESULTS

The CSF leak and clival defect were successfully repaired with this technique. Postoperative imaging demonstrated appropriate positioning of the flap as well as the location of the free-flap pedicle and anastomosis. Endoscopic evaluation at 6 months showed complete resurfacing of the previously exposed cranial base. In cadaveric dissection in 3 adult specimens, the pedicle length necessary to reach the inferior clivus and craniocervical junction from the closest recipient pedicle through a retropharyngeal route was an average of 6.5 cm vs an average of 16 cm through the transmaxillary approach.

CONCLUSION

The retropharyngeal space offers a direct route for tunneling free flaps for the repair of large clival defects during endoscopic skull-base surgery. Several advantages include a less circuitous pedicle route, mucosalization of the fascial flap, avoidance of midfacial degloving, and avoidance of potential disruption of the maxillary sinus.