Endoscopic Endonasal Approach to the Optic Canal: Anatomic Considerations and Surgical Relevance

Abstract BACKGROUND Increasing use of endoscopic endonasal surgery for suprasellar lesions with extension into the optic canal (OC) has necessitated a better endonasal description of the OC. OBJECTIVE To identify the osseous OC transcranially and then investigate its anatomic relationship to the key endonasal intrasphenoidal landmarks. We also aimed to determine and describe the technical nuances for safely opening the falciform ligament and intracanalicular dura (surrounding the optic nerve [ON]) endonasally. METHODS Ten fresh human head silicon-injected specimens underwent an endoscopic transtuberculum/transplanum approach followed by 2-piece orbitozygomatic craniotomy to allow identification of 20 OCs. After completing up to 270° of endonasal bony decompression of the OC, a dural incision started at the sella and continued superiorly across the superior intercavernous sinus. Subsequently the dural opening was extended anterolaterally across the dura of the prechiasmatic sulcus, limbus sphenoidale, and planum. RESULTS Endonasally, the length of the osseous OC was approximately 6 mm and equivalent to the length of the lateral opticocarotid recess, as measured anteroposteriorly. The ophthalmic artery arose from the supraclinoidal carotid artery at approximately 2.5 mm from the medial osseous OC entrance. Transcranial correlation of the endonasal dural incision confirmed medial detachment of the falciform ligament and exposure of the preforaminal ON. CONCLUSION The lateral opticocarotid recess allows distinction of the preforaminal ON, roofed by the falciform ligament from the intracanalicular segment in the osseous OC. This facilitates the preoperative surgical strategy regarding the extent of OC decompression and dural opening. Extensive endonasal decompression of the OC and division of the falciform ligament is feasible.

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Anatomic Nuances of the Ophthalmic Artery Origin from a Ventral Viewpoint: Considerations and Implications for Endoscopic Endonasal Surgery

Operative Neurosurgery ◽

10.1093/ons/opy188 ◽

2018 ◽

Vol 16 (4) ◽

pp. 478-485

Author(s):

Cristian A Naudy ◽

Juan C Yanez-Siller ◽

Paulo M Mesquita Filho ◽

Matias Gomez G. ◽

Bradley A Otto ◽

...

Keyword(s):

Ophthalmic Artery ◽

Internal Carotid ◽

Point Of View ◽

Endoscopic Endonasal Surgery ◽

Endonasal Surgery ◽

Endoscopic Endonasal ◽

Nerve Segment ◽

Surgical Field ◽

The Right ◽

Ophthalmic Arteries

Abstract BACKGROUND The origin of the ophthalmic artery is within the surgical field of endoscopic endonasal approaches (EEAs) to the suprasellar and parasellar regions. However, its anatomy from the endoscopic point-of-view has not been adequately elucidated. OBJECTIVE To highlight the anatomy of the ophthalmic artery origin from an endoscopic endonasal perspective. METHODS The origin of the ophthalmic artery was studied bilaterally under endoscopic visualization, after performing transplanum/transtubercular EEAs in 17 cadaveric specimens (34 arteries). Anatomic relationships relevant to surgery were evaluated. To complement the cadaveric findings, the ophthalmic artery origin was reviewed in 200 “normal” angiographic studies. RESULTS On the right side, 70.6% of ophthalmic arteries emerged from the superior aspect, while 17.6% and 11.8% emerged from the superomedial and superolateral aspects of the intradural internal carotid artery, respectively. On the left, 76.5%, 17.6%, and 5.9% of ophthalmic arteries emerged from the superior, superomedial, and superolateral aspects of the internal carotid, respectively. Similar findings were observed on angiography. All ophthalmic arteries emerged at the level of the medial opticocarotid recess. Overall, 47%, 26.5%, and 26.5% of ophthalmic arteries (right and left) were inferolateral, inferior, and inferomedial to the intracranial optic nerve segment, respectively. On both sides, the intracranial length of the ophthalmic artery ranged from 1.5 to 4.5 mm (mean: 2.90 ± standard deviation of 0.74 mm). CONCLUSION Awareness of the endoscopic nuances of the ophthalmic artery origin is paramount to minimize the risk of sight-threatening neurovascular injury during EEAs to the suprasellar and parasellar regions.

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Pontine encephalocele and abnormalities of the posterior fossa following transclival endoscopic endonasal surgery

Journal of Neurosurgery ◽

10.3171/2013.12.jns13756 ◽

2014 ◽

Vol 121 (2) ◽

pp. 359-366 ◽

Cited By ~ 21

Author(s):

Maria Koutourousiou ◽

Francisco Vaz Guimaraes Filho ◽

Tina Costacou ◽

Juan C. Fernandez-Miranda ◽

Eric W. Wang ◽

...

Keyword(s):

Posterior Fossa ◽

Fourth Ventricle ◽

Fat Graft ◽

Control Group ◽

Reconstruction Technique ◽

Endoscopic Endonasal Surgery ◽

Posterior Fossa Tumors ◽

Endonasal Surgery ◽

Endoscopic Endonasal ◽

Dural Opening

Object Transclival endoscopic endonasal surgery (EES) has recently been used for the treatment of posterior fossa tumors. The optimal method of reconstruction of large clival defects following EES has not been established. Methods A morphometric analysis of the posterior fossa was performed in patients who underwent transclival EES to compare those with observed postoperative anatomical changes (study group) to 50 normal individuals (anatomical control group) and 41 matched transclival cases with preserved posterior fossa anatomy (case-control group) using the same parameters. Given the absence of clival bone following transclival EES, the authors used the line between the anterior commissure and the basion as an equivalent to the clival plane to evaluate the location of the pons. Four parameters were studied and compared in the two populations: the pontine location/displacement, the maximum anteroposterior (AP) diameter of the pons, the maximum AP diameter of the fourth ventricle, and the cervicomedullary angle (CMA). All measurements were performed on midsagittal 3-month postoperative MR images in the study group. Results Among 103 posterior fossa tumors treated with transclival EES, 14 cases (13.6%) with postoperative posterior fossa anatomy changes were identified. The most significant change was anterior displacement of the pons (transclival pontine encephalocele) compared with the normal location in the anatomical control group (p < 0.0001). Other significant deformities were expansion of the AP diameter of the pons (p = 0.005), enlargement of the fourth ventricle (p = 0.001), and decrease in the CMA (p < 0.0001). All patients who developed these changes had undergone extensive resection of the clival bone (> 50% of the clivus) and dura. Nine (64.3%) of the 14 patients were overweight (body mass index [BMI] > 25 kg/m2). An association between BMI and the degree of pontine encephalocele was observed, but did not reach statistical significance. The use of a fat graft as part of the reconstruction technique following transclival EES with dural opening was the single significant factor that prevented pontine displacement (p = 0.02), associated with 91% lower odds of pontine encephalocele (OR = 0.09, 95% CI 0.01–0.77). The effect of fat graft reconstruction was more pronounced in overweight/obese individuals (p = 0.04) than in normal-weight patients (p = 0.52). Besides reconstruction technique, other noticeable findings were the tendency of younger adults to develop pontine encephalocele (p = 0.05) and the association of postoperative meningitis with the development of posterior fossa deformities (p = 0.05). One patient developed a transient, recurrent subjective diplopia; all others remained asymptomatic. Conclusions Significant changes in posterior fossa anatomy that have potential clinical implications have been observed following transclival transdural EES. These changes are more common in younger patients or those with meningitis and may be associated with BMI. The use of a fat graft combined with the vascularized nasoseptal flap appears to minimize the risk of pontine herniation following transclival EES with dural opening.

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Frontal mucopyocele with bone erosion in a 7-year-old child - exclusively endoscopic endonasal approach - a case report

Rhinology online ◽

10.4193/rhinol/20.090 ◽

2021 ◽

Vol 4 (4) ◽

pp. 108-112

Author(s):

A.W.D. Felippu ◽

A.J.S. Cunha ◽

A.C.S. Oliveira ◽

T.P. Morsch ◽

M.P. Limongi ◽

...

Keyword(s):

Slow Growth ◽

Bone Erosion ◽

Benign Lesion ◽

Endoscopic Endonasal Approach ◽

Endoscopic Endonasal Surgery ◽

Endonasal Surgery ◽

Endoscopic Endonasal ◽

Slow Growth Rate ◽

Important Complication ◽

Safe Approach

A mucocele is a benign lesion that predominantly affects the paranasal sinuses, with a slow growth rate and expansive pattern. When infected, it is known as mucopyocele. Presentation of a frontal mucopyocele can be found more frequently in adults. In contrast, it is rarely seen in children since pneumatization of the sinuses usually takes place after age 7. This report aims to present one case of a frontal mucopyocele as an important complication of a pansinusitis in a 7-year-old child and discuss the diagnosis, surgical approach, and differentials. Endoscopic endonasal surgery is a safe approach and must be taken into consideration in these situations.

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Sinonasal quality of life in patients after an endoscopic endonasal surgery of a sellar tumour

Scientific Reports ◽

10.1038/s41598-021-02747-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vlastimil Novák ◽

L. Hrabálek ◽

J. Hoza ◽

C.Hučko ◽

D. Pohlodek ◽

...

Keyword(s):

Quality Of Life ◽

Nasal Congestion ◽

Cranial Base ◽

Fascia Lata ◽

Endoscopic Endonasal Approach ◽

Endoscopic Endonasal Surgery ◽

Endonasal Surgery ◽

Endoscopic Endonasal ◽

Snot 22

AbstractEndoscopic endonasal approach uses the nasal cavity and paranasal sinuses to access the cranial base and may be a source of post-surgical morbidity in many patients with a sellar tumour. The objective of the presented study was to evaluate sinonasal quality of life and assess the effect of chosen reconstruction of the cranial base on the final condition. 65 patients, 33 male and 32 female who underwent an endoscopic endonasal surgery due to sellar expansion, were included into this prospective study. Sinonasal quality of life was evaluated using the Sinonasal Outcome Test-22 (SNOT-22) questionnaire before the surgery and six months after the surgery. Sinonasal quality of life was evaluated for the total cohort of patients and for patients after reconstruction (fascia lata, muscle) and without reconstruction. The minimum follow-up period was one year. There was no significant difference between the score (SNOT-22) before the surgery (average 14.4 points) and after the surgery (average 17.5 points), p = 0.067 in the whole cohort. Statistically significant differences were found in the following items—the need to blow nose, nasal congestion, loss of smell and taste, and thick discharge from the nose. The comparison of subgroups with and without the reconstruction yielded statistically significant differences in favour of patients with reconstruction in the following items—lack of high-quality sleep and feeling exhaustion. The endoscopic endonasal approach in patients with a sellar tumour is a gentle method with minimal effects on sinonasal quality of life over a period longer than six months. The most common complaints are the need to blow nose, nasal congestion, loss of smell and taste, and thick discharge from the nose. Cranial base reconstruction using the muscle and fascia lata seems to be a potential factor positively influencing sinonasal quality of life.

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Anatomical assessment of the endoscopic endonasal approach for the treatment of paraclinoid aneurysms

Journal of Neurosurgery ◽

10.3171/2018.6.jns18800 ◽

2019 ◽

Vol 131 (6) ◽

pp. 1734-1742 ◽

Cited By ~ 2

Author(s):

Ali Tayebi Meybodi ◽

Leandro Borba Moreira ◽

Andrew S. Little ◽

Michael T. Lawton ◽

Mark C. Preul

Keyword(s):

Ophthalmic Artery ◽

Internal Carotid ◽

Oculomotor Nerve ◽

Endoscopic Endonasal Approach ◽

Endoscopic Endonasal ◽

Risks And Benefits ◽

Paraclinoid Aneurysms ◽

Distal Internal Carotid Artery ◽

Dural Opening ◽

Neurovascular Structures

OBJECTIVEEndoscopic endonasal approaches (EEAs) are increasingly being incorporated into the neurosurgeon’s armamentarium for treatment of various pathologies, including paraclinoid aneurysms. However, few anatomical assessments have been performed on the use of EEA for this purpose. The aim of the present study was to provide a comprehensive anatomical assessment of the EEA for the treatment of paraclinoid aneurysms.METHODSFive cadaveric heads underwent an endonasal transplanum-transtuberculum approach to expose the paraclinoid area. The feasibility of obtaining proximal and distal internal carotid artery (ICA) control as well as the topographic location of the origin of the ophthalmic artery (OphA) relative to dural landmarks were assessed. Limitations of the EEA in exposing the supraclinoid ICA were also recorded to identify favorable paraclinoid ICA aneurysm projections for EEA.RESULTSThe extracavernous paraclival and clinoidal ICAs were favorable segments for establishing proximal control. Clipping the extracavernous ICA risked injury to the trigeminal and abducens nerves, whereas clipping the clinoidal segment put the oculomotor nerve at risk. The OphA origin was found within 4 mm of the medial opticocarotid point on a line connecting the midtubercular recess point to the medial vertex of the lateral opticocarotid recess. An average 7.2-mm length of the supraclinoid ICA could be safely clipped for distal control. Assessments showed that small superiorly or medially projecting aneurysms were favorable candidates for clipping via EEA.CONCLUSIONSWhen used for paraclinoid aneurysms, the EEA carries certain risks to adjacent neurovascular structures during proximal control, dural opening, and distal control. While some authors have promoted this approach as feasible, this work demonstrates that it has significant limitations and may only be appropriate in highly selected cases that are not amenable to coiling or clipping. Further clinical experience with this approach helps to delineate its risks and benefits.

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