Pericranial Flap-Based Multilayer Reconstruction of Endoscopic Transcribriform Craniectomy for Sinonasal Malignancies

OBJECTIVE

Diffusion of endoscopic techniques for the resection of ethmoid bone malignancies through a transcribriform approach (TA) has raised new challenges regarding reconstruction options to reduce post-operative complications. Although there is consensus on the advantages of vascularized flaps over free grafts for large defects, no standard protocol exists on reconstruction procedures. In addition, although the pedicled nasoseptal flap has been extensively discussed, few studies have been published on extranasal pedicled flaps. The aim of this manuscript is to provide a detailed description of a reconstruction technique for large anterior skull base defects with the pericranial flap as part of a multilayered reconstruction. Moreover, patients treated with this approach were retrospectively assessed for post-operative complications.

METHODS

A detailed description of the reconstruction procedure as performed in our departments is provided. Pictures depicting the main surgical steps are also included. In addition, preliminary functional results from a retrospective series of patients who underwent a TA and subsequent pericranial flap-based multilayer reconstruction for ethmoid roof malignancies between 2016 and 2022 at two institutional centers are reported.

RESULTS

16 patients were included in the study. Nine patients (56.3%) underwent adjuvant radiotherapy. Two patients had a biochemically-confirmed postoperative CSF leak. Only one of the two patients required surgical revision. During follow-up (mean 13 months), no other early nor delayed complications were observed.

CONCLUSION

A standardized surgical technique with pericranial flap as part of a multilayered reconstruction for large anterior skull base defects following resection of sinonasal malignancies is proposed, which appears to be a safe choice when endonasal flaps are not available.

LEVEL OF EVIDENCE

Level 4 Laryngoscope, 133:2942-2947, 2023.

Use of a Pericranial Flap Technique for Deep Brain Stimulation Hardware Protection and Improved Cosmesis

OBJECTIVES

Deep brain stimulation (DBS) has become an established neuromodulation therapy; however, surgical site complications such as hardware skin erosion remain an important risk and can predispose to infection, requiring explantation of the system. Nuances of surgical technique can affect wound healing, cosmetic outcome, comfort, and risk of infection. In this study, we describe our experience with a layered closure technique using a vascularized pericranial flap for improving cosmesis and protection of the implanted hardware against skin erosion and infection.

MATERIALS AND METHODS

We retrospectively reviewed 636 individuals (746 lead implantations) who underwent DBS surgery by a single academic neurosurgeon between 2001 and 2020. A layered pericranial flap closure technique for the burr-hole and connector sites was instituted in 2015. We assessed the effects of a multimodal infection prevention approach that included the pericranial flap on hardware complication rates compared with the premultimodality cohort, and we report the nuances of the technique.

RESULTS

In our institutional experience, we found that implementation of a pericranial flap closure technique can enhance the subjective cosmetic result at the burr-hole cover site and increase patient comfort and satisfaction. In addition, we found a decrease in hardware infection rates in the current cohort with a multimodal infection prevention regimen that includes the pericranial-flap technique (n = 256, 2015-2020 period) to 1.2% (p = 0.006), from 6.9% in the earlier cohort (n = 490, 2001-2015 period).

CONCLUSIONS

The report highlights the potential of a pericranial-flap closure technique as a surgical adjunct to improve DBS surgical site healing and cosmesis and may, as part of a multimodal strategy, contribute to decreased risk of skin breakdown and hardware infection.

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.

Magnetic Resonance Imaging Study of the Pericranial Flap and Its Local Effects Following Endoscopic Craniofacial Resection

OBJECTIVES/HYPOTHESIS

To describe the magnetic resonance imaging (MRI) characteristics of the pericranial flap, changes in the pericranial flap thickness over time, presence of frontal sinus opacification, and presence of frontal lobe herniation into the nasal cavity.

STUDY DESIGN

Retrospective case series.

METHODS

Seventeen consecutive endoscopic craniofacial resections with pericranial flap reconstruction performed at a tertiary hospital from 2010 to 2019 were reviewed. Sixty-eight serial MRI scans were evaluated.

RESULTS

All pericranial flaps consistently featured a homogenous appearance on T1-weighted sequence and enhanced with contrast. On T2-weighted sequence, the skull base reconstruction demonstrated four layers of alternating hypo- and hyperintensity, which corresponded with the inlay synthetic graft or neodura (hypointense), loose areolar tissue (hyperintense), fibrous pericranium (hypointense), and nasal mucosa or granulation tissue (hyperintense). The mean pericranial flap thickness was 9.9 mm. In thicker flaps, the loose areolar layer contributed the bulk of the thickness. Of 13 patients who underwent three or more serial MRI scans, 11 flaps (84.6%) were stable and two (15.4%) had >50% reduction in their original thickness over time. Thirteen of 17 (76.5%) patients had frontal sinus opacification on follow-up. None developed frontal sinus mucoceles or frontal lobe herniation.

CONCLUSIONS

The pericranial flap has a distinctive MRI appearance, especially on T2-weighted sequence. The thickness of the flap remains relatively stable over time for most patients even following radiotherapy. It is a sturdy flap that is able to support the frontal lobe. Frontal sinus obstruction is common, although complications from this appear to be rare.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E90-E97, 2021.

Surgical Management of Deep Brain Stimulator Infection without Electrode Removal: Report of Two Cases

Objective  Stimulation of the subthalamic nucleus by implanted electrodes (deep brain stimulation [DBS]) is performed to suppress symptoms of Parkinson's disease. However, postoperative wound dehiscence and infection can require removal of the implanted electrode leads. This report describes treatment of intractable unilateral wound infection in two patients without removing the DBS device. Methods  First, components of the DBS system were removed except for the electrode lead and thorough debridement of the infected wound was conducted. Second, the edges of the bone defect left by removal of DBS components were smoothed to eliminate dead space. Subsequently, the electrode lead was covered by using a pericranial-frontalis-muscle flap or a bi-pedicled-scalp flap with good blood supply. Closed intrawound continuous negative pressure and irrigation treatment was conducted for 1 week after the surgery, and then the drain was removed. Results  We treated two patients with wound infection after implantation of DBS electrodes. Case 1 developed a cutaneous fistula and Case 2 had wound dehiscence. After treatment by the method described above, complete wound healing was achieved in both patients. Conclusion  DBS is always associated with a risk of infection or exposure of components and treatment can be very difficult. We successfully managed intractable wound infection while leaving the electrode lead in situ, so that it was subsequently possible to continue DBS for Parkinson's disease.

Regional Reconstruction of Orbital Exenteration Defects

Aggressive disease such as invasive fungal infections or malignancies may necessitate orbital exenteration. The defects of orbital exenteration are often complex involving adjacent structures. Rehabilitation of the orbital exenteration defect poses unique challenges to the reconstructive surgeon. Various options have been described ranging from secondary intention to microvascular free tissue reconstruction. Here the authors review local/regional options for reconstruction of orbital exenteration defects.

Pediatric Diffuse Large B-Cell Lymphoma of the Frontal Sinus: A Case Report

An 11-year-old male presented with right proptosis, bulbar conjunctivitis, and diplopia. Computerized tomography (CT) and magnetic resonance imaging revealed an enhancing mass involving the superio-medial orbit, ethmoids, frontal sinus, and anterior cranial fossa with skull base destruction. Diffuse large B-cell lymphoma was diagnosed via CT-guided biopsy. As a component of multidisciplinary care, the patient underwent frontal sinus cranialization, with orbital and skull base reconstruction. Trauma reconstructive principles guided recreation of orbital, frontal sinus, and anterior skull base anatomy. This rare primary location is undescribed in the pediatric literature.

Clinical Experience with Secondary Endoscopic Reconstruction of Clival Defects with Extracranial Pericranial Flaps

Objectives  The aim of this study is to report the clinical outcome of extracranial pericranial flaps (ePCF) used for reconstruction of clival dural defects following failure of primary repair. Design  Retrospective review of skull base database. Setting  Academic medical center. Participants  Patients undergoing reconstruction of clival defects with ePCF following endoscopic endonasal surgery (EES). Main outcome measures  Postoperative cerebrospinal fluid (CSF) leak, meningitis, and flap necrosis. Results  Seven patients (five males and two females) who underwent ePCF reconstruction for clival defects following EES were included. All patients (ages 8-64 years) had a postoperative CSF leak due to a failed primary clival reconstruction (five had one, one had two, and one had three failed CSF leak repairs prior to ePCF reconstruction). Nasoseptal and inferior turbinate (lateral nasal wall) flaps were not available for secondary reconstruction due to prior surgeries. The immediate success rate of ePCF for the reconstruction of clival defects in patients with multiple flap failures was 58%. Two patients developed CSF leaks that were successfully repaired endoscopically with the addition of free tissue grafts; one patient had partial flap necrosis that required debridement; none required an additional vascularized flap. Width of the defect, length of the defect, properties of the ePCF, and age did not demonstrate significance ( p  > 0.05) for adverse outcome. Conclusion  An ePCF is a reconstructive option for high-risk, large clival defects when other local and regional vascularized flaps are not available or fail. ePCFs can be used for reconstruction of clival defects in all populations, including pediatric patients.

Endoscopic pericranial flap design for the restoration of nasal mid-vault lining defects

Despite progress made in nasal reconstruction, the restoration of a large defect, including the whole septum and mid-nasal vault structures, remains a challenge. The pericranial flap (PCF) is used widely for the reconstruction of anterior cranial fossa defects. This article presents a surgical technique for nasal lining restoration with an endoscopic PCF design. This technique was used in patients with huge intranasal tumours. Two patients with nasal eosinophilic angiocentric fibrosis were treated. The structural involvement was similar in each case. The tumour was resected completely by combined endoscopic and external methods through an open rhinoplasty approach. The resulting defect included the whole nasal septum, bilateral upper lateral cartilage, and the entire mid-nasal vault mucosal lining. Reconstruction was achieved by endoscopic PCF design for internal lining reconstruction and rib cartilage for framework repair. The first patient was followed up for 18months and the second for 8months. No infection occurred in the postoperative period. Framework stability and texture were good, and both nasal shapes were acceptable. In conclusion, this endoscopic PCF approach for restoring the internal nasal lining appears to be a good choice in selected cases.

Radio-anatomical analysis of the pericranial flap "money box approach" for ventral skull base reconstruction

OBJECTIVES/HYPOTHESIS

To evaluate the versatility of the pericranial flap (PCF) to reconstruct the ventral skull base, using the frontal sinus as a gate for its passage into the sinonasal corridor "money box approach."

STUDY DESIGN

Anatomic-radiological study and case series.

METHODS

Various approaches and their respective defects (cribriform, transtuberculum, clival, and craniovertebral junction) were completed in 10 injected specimens. The PCF was introduced into the nose through the uppermost portion of the frontal sinus (money box approach). Computed tomography (CT) scans (n = 50) were used to measure the dimensions of the PCF and the skull base defects. The vertical projection of the external ear canal was used as the reference point to standardize the incisions for the PCF.

RESULTS

The surface area and maximum length of the PCF were 121.5 ± 19.4 cm² and 18.3 ± 1.3 cm, respectively. Using CT scans, we determined that to reconstruct defects secondary to transcribriform, transtuberculum, clival, and craniovertebral approaches, the PCF distal incision must be placed respectively at -3.7 ± 2.0 cm (angle -17.4 ± 8.5°), -0.2 ± 2.0 cm (angle -1.0 ± 9.3°), +5.5 ± 2.3 cm (angle +24.4 ± 9.7°), +8.4 ± 2.4 cm (angle +36.6 ± 11.5°), as related to the reference point. Skull base defects in our clinical cohort (n = 6) were completely reconstructed uneventfully with the PCF.

CONCLUSIONS

The PCF renders enough surface area to reconstruct all possible defects in the ventral and median skull base. Using the uppermost frontal sinus as a gateway into the nose (money box approach) is feasible and simple.

LEVEL OF EVIDENCE

NA. Laryngoscope, 127:2482-2489, 2017.

Endoscopic Endonasal Reconstructive Methods to the Anterior Skull Base

The success of expanded endoscopic endonasal approaches (EEAs) to the anterior skull base, sellar, and parasellar regions has been greatly aided by the advancement in reconstructive techniques. In particular, the pedicled vascularized flaps have been developed and effectively cover skull base defects of varying sizes with a significant reduction in postoperative CSF leaks. There are two aims to this review: (1) We will provide our current, simplified reconstruction algorithm. (2) We will describe, in detail, the relevant anatomy, indications/contraindications, and surgical technique, with a particular emphasis on the nasoseptal flap (NSF). The inferior turbinate flap (ITF), middle turbinate flap (MTF), pericranial flap (PCF), and temporoparietal fascial flap (TPFF) will also be described. The NSF should be the primary option for reconstruction of majority of skull base defects following endonasal endoscopic surgery. In general, for the planum, cribriform, and upper two-thirds of the clivus, the NSF is ideal. For the lower-third of the clivus, the NSF may not be adequate and may require additional reconstructive options. Although limited in reach or more technically challenging, these reconstructive flaps should still be considered and kept in the surgical algorithm.

Large Septal Perforation Repair with Pericranial Flap and Intraoperative Fluorescence Angiography

Septal perforations present a challenging dilemma for surgical intervention when medical therapy fails. Multiple techniques have been described in the literature to address perforations using numerous techniques; however, there have been varying rates of success and reproducibility reported. The use of a large, pericranial flap was previously described to repair large septal perforation. The objective of this case report is to describe the use of a pedicled pericranial flap in combination with intraoperative fluorescence angiography to quantify vascular perfusion. This article presents a 31-year-old man with an idiopathic, septal perforation measuring 1.7 × 1.7 cm who previously failed medical therapy and surgical repair. He underwent a combined, coronal incision and external rhinoplasty approach with a tunneled pericranial flap resulting in a successful repair. This case report illustrates robust reconstructive capability of pericranial flaps for repair of septal perforations, as well as the potential value of intraoperative fluorescence angiography in determining the likelihood of a successful outcome.

Surgical management of traumatic frontal sinus fractures: Case series from a single institution and literature review

BACKGROUND

Neurosurgeons are frequently involved in the management of patients with traumatic frontal sinus injury; however, management options and operative techniques can vary significantly. In this study, the authors review the current literature and retrospectively review the clinical series at a single tertiary referral center.

METHODS

After Institutional Review Board approval, the medical records and computed tomographic (CT) imaging of patients whose traumatic frontal sinus fractures were treated surgically at the University of Utah were retrospectively reviewed. Demographic information, mechanism of injury, associated injuries, operative technique, and pattern of injury on CT were analyzed.

RESULTS

Between 2000 and 2012, 33 patients underwent successful cranialization of the frontal sinus following traumatic injury. The material used to obliterate the sinus varied. No patients required immediate or delayed reoperation. Nasofrontal outflow tract obstruction, the importance of which has been emphasized in the plastic surgery literature, was apparent on either initial or retrospective review of the available CT imaging in 96%.

CONCLUSIONS

In this series, we successfully surgically treated 33 patients with frontal sinus fractures. The presence of cerebrospinal fluid leak, nasofrontal outflow tract injury, associated depressed skull fractures, and subsequent formation of communicating pathways and infection must be considered when constructing a treatment plan. The goals of treatment should be: (i) surgical repair of the defect and elimination of the conduit from the intracranial space to the outside and (ii) elimination of any cerebrospinal fluid pressure gradient that may develop across the surgical repair. We present a treatment algorithm focusing on the presence of nasofrontal outflow tract injury/obstruction, cosmetic deformity, and cerebrospinal fluid leak.

How to choose? Endoscopic skull base reconstructive options and limitations

As endoscopic skull base resections have advanced, appropriate reconstruction has become paramount. The reconstructive options for the skull base include both avascular and vascular grafts. We review these and provide an algorithm for endoscopic skull base reconstruction. One hundred and sixty-six skull base dural defects, reconstructed with an endonasal vascular flap, were examined. As an adjunct, avascular reconstruction techniques are discussed to illustrate all options for endonasal skull base reconstruction. Cerebrospinal fluid (CSF) leak rates are also discussed. Small CSF leaks may be successfully repaired with various avascular grafting techniques. Endoscopic endonasal approaches (EEAs) to the skull base often have larger dural defects with high-flow CSF leaks. Success rates for some EEA procedures utilizing avascular grafts approach 90%, yet in high-flow leak situations, success rates are much lower (50 to 70%). Defect location and complexity guides vascularized flap choice. When nasoseptal flaps are unavailable, anterior/sellar defects are best managed with an endoscopically harvested pericranial flap, whereas clival/posterior defects may be reconstructed with an inferior turbinate or temporoparietal flap. An endonasal skull base reconstruction algorithm was constructed and points to increased use of various vascularized reconstructions for more complex skull base defects.