The pterional approach and extradural anterior clinoidectomy to clip paraclinoid aneurysms

Endoscopic Endonasal Transsphenoidal Approach to Repair Cerebrospinal Fluid Rhinorrhea After an Anterior Clinoidectomy for Aneurysm Clipping: Series of 4 Cases

BACKGROUND

Cerebrospinal fluid (CSF) rhinorrhea through a pneumatized optic strut is a known potential complication after an anterior clinoidectomy that is used to microsurgically clip a proximal internal carotid artery aneurysm. The original craniotomy site can be reopened to repair the skull base defect, but this technique has disadvantages.

OBJECTIVE

To avoid a repeat craniotomy and address the limitations of a transcranial approach, a straightforward alternative was used for skull base repair-the binostril endoscopic endonasal transsphenoidal approach.

METHODS

This retrospective case series describes the use of endoscopic transsphenoidal repair and outcomes for patients with CSF leaks after anterior clinoidectomy for aneurysm repair between January 1, 2015, and December 31, 2019.

RESULTS

Four adult patients (3 women and 1 man) with a mean age of 59.5 years were reviewed. Skull base repair occurred on average 24 days (range, 4-75 days) after the index operation. After demucosalization of the parasellar sphenoid sinus, the fistula in the pneumatized optic strut was reconstructed with a free nasal mucosal graft with or without an autologous muscle graft. None of the patients developed a recurrent CSF leak at a mean follow-up of 12.5 months (range, 8-22 months), and none experienced complications.

CONCLUSION

The endoscopic endonasal transsphenoidal approach was safe and effective for skull base repair in 4 patients with CSF rhinorrhea after an anterior clinoidectomy for aneurysm clipping.

Clinical analysis of cavernous sinus anatomy, pathologies, diagnostics, surgical management and complications - comprehensive review

For decades, the cavernous sinus (CS) has been the subject of debates and scientific studies aimed at elucidating its anatomical variability, and at choosing the best method for accessing it so that optimal diagnoses and related surgical treatments can be decided. The present review considers a series of issues related to the CS. The anatomy of the CS and its features is explored first, and the most important structures, spaces and morphological variations are considered. This is followed by CS pathology and selected diagnostic methods that have proved useful in therapy, and then the management of these pathologies is discussed. Examples of therapeutic steps that have proved helpful in specific cases are taken from the literature. Finally, the various surgical accesses and complications that can be encountered during invasive interventions in the CS area are discussed. The aim of this study is to summarize up-to-date anatomical and clinical knowledge about the CS, citing the most informative scientific papers and aggregating their results. Morphological variations of the CS are common but have not been well described in the literature.

Clipping Ophthalmic Segment Artery Aneurysms Using a Modified Subdural Dolenc Approach: Classification and Experience Sharing

BACKGROUND

Ophthalmic segment artery aneurysms (OSAs) are difficult to clip; therefore, improvement of the surgical method is of great significance to the prevention of complications, and the classification of the aneurysms is essential to formulate a reasonable surgical plan.

OBJECTIVE

To explore the strategies and effects of surgery for OSAs using a modified subdural Dolenc approach.

METHODS

The clinical data of 38 patients (12 men and 26 women, aged 48-73 years) with OSA were analyzed retrospectively. A total of 44 aneurysms were identified, 40 of which were OSAs. The 40 aneurysms were divided into types Ia1 (n = 2), Ia2 (n = 2), Ib (n = 6), IIa (n = 4), IIb (n = 4), IIIa (n = 0), IIIb (n = 4), IIIc (n = 16), and IV (n = 2) based on preoperative images. Thirty-nine OSAs were operated successfully through pterional craniotomy combined with the modified subdural Dolenc approach, and 1 aneurysm was clipped through the contralateral approach. Clinical outcomes were evaluated using the Glasgow Outcome Scale (GOS).

RESULTS

Thirty-nine OSAs were clipped, and one was wrapped. Visual dysfunction, headache, and dizziness improved after the operation in 18 patients. One patient had new visual impairment, and there were no deaths. At discharge, the GOS score was 5 in 36 cases, 4 in 1 case, and 3 in 1 case. Thirty-seven patients had a GOS score of 5, and 1 patient had a score of 3 at 6 months after the operation.

CONCLUSION

The modified subdural Dolenc approach (Zheng approach) for clipping OSAs may be associated with less trauma and good postoperative outcomes.

Anterior clinoidectomy using an extradural and intradural 2-step hybrid technique

In Brief: The authors found a practical intraoperative landmark to localize the optic strut during anterior clinoidectomy and used it as the basis for performing anterior clinoidectomy in two steps: extradural phase and intradural phase. This anatomically based technique can increase the safety of anterior clinoidectomy by providing easily identifiable landmarks and reducing intradural bone drilling, which could put the adjacent neurovauscular structures at risk.

The Extended Lateral Supraorbital Approach and Extradural Anterior Clinoidectomy Through a Frontopterio-Orbital Window: Technical Note and Pilot Surgical Series

BACKGROUND

Lateral approaches to treat anterior cranial fossa lesions have evolved since the first frontotemporal approach described by Dandy in 1918. We describe a less invasive approach to perform extradural anterior clinoidectomy through a lateral supraorbital (LSO) approach for anterior circulation aneurysms and anterolateral skull base lesions.

METHODS

The extended LSO approach involves performing a standard lateral supraorbital craniotomy followed by drilling of the sphenoid wing and lateral wall of the orbit through the frontal bony opening of the LSO approach, without any temporal extension of the craniotomy. This creates a frontopterio-orbital window exposing the periorbita; superior, medial, and anterior aspect of the temporal dura mater; and superior orbital fissure. After unroofing the superior orbital fissure, the meningo-orbital fold is cut, and the temporal dura mater is peeled from the lateral wall of the cavernous sinus to expose the anterior clinoid process allowing a standard opening of the optic canal and anterior clinoidectomy.

RESULTS

The extended LSO approach and extradural anterior clinoidectomy allowed access to 4 sphenoid wing/anterior clinoidal meningiomas, 5 anterior circulation aneurysms, 2 temporomesial lesions, and 1 orbital/cavernous sinus abscess. Postoperatively, 2 patients had transient hemiparesis, 2 patients had transient third nerve palsy, and 1 patient had minimal visual field deterioration. All patients had a modified Rankin Scale score ≤1 at 8-week follow-up.

CONCLUSION

The extended LSO approach opens a new route (frontopterio-orbital window) to perform extradural anterior clinoidectomy safely and increases surgical exposure, angles, and operability of a less invasive keyhole craniotomy (LSO approach) to treat anterior cranial fossa lesions.

Ten Triangles around Cavernous Sinus for Surgical Approach, Described by Schematic Diagram and Three Dimensional Models with the Sectioned Images

For the surgical approach to lesions around the cavernous sinus (CS), triangular spaces around CS have been devised. However, educational materials for learning the triangles were insufficient. The purpose of this study is to present educational materials about the triangles, consisting of a schematic diagram and 3-dimensional (3D) models with sectioned images. To achieve the purposes, other studies were analyzed to establish new definitions and names of the triangular spaces. Learning materials including schematic diagrams and 3D models with cadaver's sectioned images were manufactured. Our new definition was attested by observing the sectioned images and 3D models. The triangles and the four representative surgical approaches were stereoscopically indicated on the 3D models. All materials of this study were put into Portable Document Format file and were distributed freely at our homepage (anatomy.dongguk.ac.kr/triangles). By using our schematic diagram and the 3D models with sectioned images, ten triangles and the related structures could be understood and observed accurately. We expect that our data will contribute to anatomy education, surgery training, and radiologic understanding of the triangles and related structures.