Defining the limits and indications of the Draf III endoscopic approach to the lateral frontal sinus and maximizing visualization and maneuverability: a cadaveric and radiological study

Benign bony lesions of paranasal sinuses and skull base: from osteoma to fibrous dysplasia

PURPOSE OF REVIEW

Benign bony lesions of the craniofacial complex are relatively common. However, their location close to critical neurovascular structures may render their treatment, if required, highly challenging.This article reviews the current literature on their pathophysiology, diagnosis, natural course and treatment, with a focus on most recent findings.

RECENT FINDINGS

A new classification has been suggested concerning endoscopic resectability. The ratio of lateral frontal to interorbital distance can accurately and reliably predict the endoscopic reach to lateral frontal sinus, while orbital transposition can assist us in reaching lateral frontal sinus when anatomy is unfavorable. New and combined endoscopic transnasal and transorbital approaches are now in the surgical armamentarium. Prophylactic optic nerve decompression in fibrous dysplasia is absolutely contraindicated as it leads to worse visual outcomes. Radiotherapy of such lesions is of no benefit and may lead to a higher risk of malignant transformation. The presence of Guanine Nucleotide binding protein Alpha Stimulating (GNAS) mutation in chromosome 20 is universally present in fibrous dysplasia and can differentiate them from ossifying fibromas.

SUMMARY

Diagnosis and therapeutic management of benign craniofacial bone lesions remains challenging. If surgical treatment is contemplated, the morbidity of the intervention should always be weighed against the potential benefits. Evolution of extended endoscopic endonasal and transorbital surgery means that more lesions can be reached purely endoscopically with better oncological and cosmetic results.

360 Degrees Endoscopic Access to and Through the Orbit

The treatment of pathologies located within and surrounding the orbit poses considerable surgical challenges, due to the intricate presence of critical neurovascular structures in such deep, confined spaces. Historically, transcranial and craniofacial approaches have been widely employed to deal with orbital pathologies. However, recent decades have witnessed the emergence of minimally invasive techniques aimed at reducing morbidity. Among these techniques are the endoscopic endonasal approach and the subsequently developed endoscopic transorbital approach (ETOA), encompassing both endonasal and transpalpebral approaches. These innovative methods not only facilitate the management of intraorbital lesions but also offer access to deep-seated lesions within the anterior, middle, and posterior cranial fossa via specific transorbital and endonasal corridors. Contemporary research indicates that ETOAs have demonstrated exceptional outcomes in terms of morbidity rates, cosmetic results, and complication rates. This study aims to provide a comprehensive description of endoscopic-assisted techniques that enable a 360° access to the orbit and its surrounding regions. The investigation will delve into indications, advantages, and limitations associated with different approaches, while also drawing comparisons between endoscopic approaches and traditional microsurgical transcranial approaches.

Comprehensive access strategies to the frontal sinus

PURPOSE OF REVIEW

Despite the impressive evolutions in endoscopic endonasal approaches and instrumentations, the frontal sinus remains a challenging area. Different surgical options have been described over the years, but the main criticism lies in choosing the most suitable approach for a given case, based on the anatomy of each patient and the disease to treat. The purpose of this study is to provide a comprehensive review of surgical access strategies currently available to address the frontal sinus, including both endonasal and traditional external procedures, analysing indications, contraindications, complications and outcomes.

RECENT FINDINGS

Frontal sinus surgery includes minimally invasive endonasal approaches (balloon dilatation, Draf type I); extended endonasal approaches (Draf type IIA-IIB-IIC, Draf type III and their modifications via orbital transposition and contralateral pyriform aperture resection); external procedures (superior eyelid incision, frontal osteoplastic flap, Riedel procedure, Riedel-Mosher operation); and combined approaches.

SUMMARY

Recent advances in endoscopic endonasal techniques have deeply reshaped the surgical options to manage frontal sinus diseases, in an attempt to minimize the invasiveness of the procedures and maximize their outcomes. Traditional external procedures should be used in selected cases nonamenable for endonasal surgery. The appropriate selection of cases appears to be of paramount importance to obtain successful outcomes.