Opticocarotid Recess Research Articles

Analysis of the Medial Opticocarotid Recess in Patients with Pituitary Macroadenoma Using Three-Dimensional Images

The medial opticocarotid recess (MOCR), which contains the lateral tubercular recess (LTR), is an important landmark for the cavernous internal carotid artery (ICA) and for accessing the parasellar and suprasellar regions. These microanatomic landmarks for endoscopic endonasal surgery can be observed using surgical simulation with three-dimensional images. The aim of this study was to analyze the MOCR in patients with pituitary macroadenoma using three-dimensional images. We constructed three-dimensional computed tomography images of 20 patients with pituitary macroadenoma and 20 patients with unruptured aneurysms as a control. Using these images, we measured the distance between the left and right LTR, the midline and the unilateral LTR, and the left and right ICA. The distance between the left and right LTR was statistically longer in the pituitary adenoma group versus the control group. Tumor volumes were multivariate parameters for the distance between the left and right LTR, which was significantly longer in the group with tumor volumes >5 cm(3) versus the other groups. This distance was also significantly correlated with the distance between the left and right ICA. Pituitary macroadenomas expand the distance between the left and right MOCR together with the distance between the left and right ICA.

Morphometric analysis of the medial opticocarotid recess and its anatomical relations relevant to the transsphenoidal endoscopic endonasal approaches.

The medial opticocarotid recess (MOCR) is located in the posterior wall of the sphenoid sinus, medial to the junction of the optic canal (OC) and the carotid prominence (CP). There is controversy in the literature in relation to the presence of the MOCR and its constancy, which is relevant when approaching the skull base through an endoscopic route. The morphometric relations of the MOCR with the surrounding structures were studied in 18 cadaveric specimens after endoscopic endonasal approach (EEA). The distance between both MOCR was 11.06 ± 1.14 mm; the distance between the MOCR and the lateral opticocarotid (LOCR) recess was 5.56 ± 0.85 mm; the distance between the MOCR and the suprasellar recess was 3.72 ± 0.49 mm; the angle between the MOCR plane and the OC 13.32 ± 2.30°; the angle between the MOCR plane and the CP 13.50 ± 2.68° and; the angle between the OC and the CP 26.81 ± 4.26°. All measurements showed low variability, with low standard deviation and interquartile range. No relations were found between any of the measurements. The MOCR may be used as a reference point for precise location of structures during EEA. Objective measurements may be especially useful in cases with distorted sphenoid bone anatomy.

Morphological Characteristics of the Sphenoid Sinus and Endoscopic Localization of the Cavernous Sinus.

The aim of this study was to investigate the relationship between the morphological characteristics of the sphenoid sinus and endoscopic localization of the cavernous sinus (CS) using an extended endoscopic endonasal transsphenoidal approach. Thirty sides of CS in 15 adult cadaver heads were dissected to simulate the extended endoscopic endonasal transsphenoidal approach, and the morphology of the sphenoid sinus and anatomic structures of CS were observed. The opticocarotid recess (OCR), ophthalmomaxillary recess (V1V2R), and maxillomandibular recess (V2V3R) in the lateral wall of the sphenoid sinus were presented in 16 sides (53.3%), 6 sides (20%), and 4 sides (13.3%) of the 30 sides, respectively. OCR is a constant anatomic landmark in endoscopy and coincides with the anterior portion of the clinoidal triangle. The C-shaped internal carotid artery (ICA) in the lateral wall of the sphenoid sinus was presented in 11 sides (36.7%), the upper one-third of which corresponds to the middle portion of the clinoidal triangle, and the lower two-thirds of which correlates to the supratrochlear triangle, infratrochlear triangle, and ophthalmic nerve in CS, around which the medial, lateral, and anteroinferior interspaces are distributed. From a front-to-behind perspective, the C-shaped ICA consists of inferior horizontal segment, anterior vertical segment, clinoidal segment as well as partial subarachnoid segment of the ICA. OCR and C-shaped ICA in the lateral wall of the sphenoid sinus are the 2 reliable anatomic landmarks in the intraoperative location of the parasellar region of CS.

Endoscopic Endonasal Approach to the Optic Canal

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. 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. 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. 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. 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.

Endoscopic transsphenoidal resection of sellar tumors with conchal sphenoid sinus: A report of two cases.

A conchal non-pneumatized sphenoid sinus was previously considered to be a contraindication to the endoscopic transsphenoidal route to the sella due to its small sellar floor and poor anatomical landmarks, such as the optic nerve canal, opticocarotid recess and internal carotid arteries canal. The present study aimed to investigate the methodology and characteristics of the endoscopic transsphenoidal resection of sellar tumors with a conchal sphenoid sinus. Two patients with sellar tumor patients and non-pneumatized sphenoid sinuses received endoscopic transsphenoidal surgery. The two conchal sphenoid sinuses were accessed safely, total resection was achieved and no serious complications occurred. Therefore, the presence of a conchal non-pneumatized sphenoid is not an absolute contraindication for employing the endoscopic transsphenoidal route in the resection of sellar tumors; a positive outcome may be achieved, in particular when the surgery is performed by an experienced otolaryngologist.

Comparing operative exposures of the le fort I osteotomy and the expanded endoscopic endonasal approach to the clivus.

Objectives We compare surgical exposures to the clivus by Le Fort I osteotomy (LFO) and the expanded endoscopic endonasal approach (EEEA). Methods Ten cadaveric specimens were imaged with 1.25-mm computed tomography. After stereotactic navigation, EEEA was performed followed by LFO. Clival measurements included lateral and vertical limits to the midline lower extent of exposure (t test). Results For EEFA and LFO, respectively, maximal lateral exposure in millimeters (mean ± standard deviation) was 24.5 ± 3.7 and 24.5 ± - 3.8 (p = 0.99) at the opticocarotid recess (OCR) and 25.1 ± - 4.1 and 24.1 ± - 3.0 (p = 0.53) at the foramen lacerum level; lateral reach at the hypoglossal canals was 39.0 ± - 5.88 and 56.1 ± - 5.3 (p = 0.0004); and vertical extension was 56.0 ± - 4.1 and 56.3 ± - 3.4 (p = 0.78). Conclusions For clival exposures, LFO and EEEA were similar craniocaudally and laterally at the levels of the OCR and foramen lacerum. LFO achieved greater exposure at the level of the hypoglossal canal.

Allergic Fungal Sinusitis Infratemporal Fossa Involvement: Saudi Experience

Objectives: Allergic fungal rhinosinusitis (AFRS) is well known to expand and to extend to the surrounding structures like the orbit and the brain; however, it has not been reported to extend to the infratemporal fossa (ITF). Because of the difficulty of accessing the ITF, we report our experience over 5 years. Methods: One hundred one patients with AFRS were operated upon by the author between 2008 and 2013. Results: All of these patients had preoperative computed tomography scans (CTs), and all but 2 had postoperative CT of the paranasal sinus. Twelve had expansion or extension of the disease into the ITF: 8 males and 4 females, their ages ranged from 10 to 34 years with mean of 20.4 years. Four of them were children below 15 years of age. Three patients had bilateral disease and 9 had unilateral sinus involvement. Seven cases had expansion of the posterior wall of the maxillary sinus into the ITF, which was unilateral and mil; however, extension from the sphenoid sinus was more extensive in most of the cases; bilateral in 2 and unilateral in the others. Conclusions: ITF extension from the sphenoid sinus is more extensive than from the maxillary sinus. In a pediatric population, because of the incomplete fusion of the suture line, the disease expanded and eroded into the ITF. In adults, the opticocarotid recess is the weakest area and the disease can expand through it into the ITF. Posterior wall of maxillary sinus expansion into the ITF is mild in all cases, and all the ITF extensions were cured endoscopically.

Anatomic study and clinical significance of extended endonasal anterior skull base surgery.

This study is to investigate the anatomical relationship of endonasal approach for anterior skull base surgery, and to determine the boundaries between anterior basicranial craniotomy and the security of operative techniques. A total of 10 adult dry skulls and 13 adult cadaveric heads processed by formalin were examined under operating microscope. The micro-anatomic structures of the turbinate, sphenoid sinus, ethmoid sinus, anterior ethmoidal artery, posterior ethmoidal artery and anterior skull base were observed. Artificial anatomy was performed and the deep-seated regions of the surgical approach were observed under operating microscope and endoscope. Examined from the intracranial and intranasal aspects, it was found that the middle turbinate, uncinate process, ethmoid bulla, lamina papyracea, anterior ethmoid canal, posterior ethmoid canal, prominence of the optic canal and opticocarotid recess were all important anatomic landmarks for surgery. The horizontal distances between medial orbital wall on both sides at the level of crista galli, anterior ethmoid canal, and posterior ethmoid canal were (22.31 ± 3.08) mm, (23 ± 2.93) mm, and (26.25 ± 2.88) mm, respectively. The distance between the double optic canal cranial opening was (14.67 ± 3.82) mm. During the endonasal approach for anterior skull base surgery, full advantage of the surgical corridor made by the middle turbinate resection should be taken. To control intraoperative bleeding, it is critical to identify anterior and posterior ethmoidal artery. Identification and protection of medial orbital wall and the optic nerve, and controlling the ranges of anterior basicranial craniotomy are of great importance for surgical safety.

The Recesses of the Sellar Wall of the Sphenoid Sinus and Their Intracranial Relationships

The sellar wall of the sphenoid sinus and its recesses have been previously studied, but their intracranial relationships to the diaphragma sellae, tuberculum, clinoid segment of the internal carotid artery, chiasmatic sulcus, and middle clinoid process need further definition. To describe these intra- and extracranial relationships of the recesses in the anterior sellar wall. The middle clinoid was studied in 132 parasellar areas of dry crania. Thirty-eight parasellar areas of formalin-fixed/silicone-colored specimens were dissected. After transsphenoidal endoscopic exposure, the optic, carotid, and sellar prominences; lateral opticocarotid and tuberculum recesses; and caroticosellar and medial opticocarotid points were identified. High-speed drills opened 1-mm perforations at these points to allow study of intracranial relationships. Two recesses and 2 junction points can be recognized in the sphenoid sinus: lateral opticocarotid and tuberculum recesses and medial opticocarotid and caroticosellar points. The lateral opticocarotid recess corresponds to the optic strut base, and the clinoid segment of the internal carotid artery is located medially. The diaphragma sellae attachment is at the level of the tuberculum recess, which in 50% of cases corresponds to the tuberculum. A middle clinoid in base or height greater than 1.5 mm is present in 21.1% and a caroticoclinoid ring in 3%. The middle clinoid is 1 mm inferior and lateral to the caroticosellar point and 4.7 mm inferior to the medial opticocarotid point. An understanding of the intra- and extracranial relationships of the recesses of the sphenoid sinus will aid in accurately directing transsphenoidal approaches.

The Medial Opticocarotid Recess

The medial opticocarotid recess (MOCR) has become an important landmark for endoscopic approaches to the cranial base. To examine the anatomy of the MOCR and outline its role as a "key landmark" for approaches to the sellar and suprasellar regions. Ten silicone-injected cadaveric specimens and 96 dry crania were examined. Dissections were done endoscopically and microscopically. The lateral tubercular recess is an osseous depression located at the lateral edge of the tuberculum when viewed from the sphenoid sinus. Intracranially, it corresponds to the lateral tubercular crest (LTC), a ridge situated at the superomedial aspect of the carotid sulcus. The MOCR is a teardrop-shaped osseous indentation formed at the medial junction of the paraclinoid carotid canal and the optic canal. Dorsally, it is represented by a teardrop-shaped area with vertices at the inferior aspect of the LTC, the medial aspect of the junction of the superior and posterior surfaces of the optic strut, and the superolateral aspect of the tuberculum. The middle clinoid process is situated inferior to the LTC. The distal osseous arch of the carotid sulcus connects the lateral opticocarotid recess to the lateral tubercular recess and is a landmark for the paraclinoid internal carotid artery. Only 44% of the specimens had middle clinoid processes. The MOCR and middle clinoid process are distinct structures. Because of its location at the confluence of the optic canal, the carotid canal, the sella, and the anterior cranial base, the MOCR is a key landmark for endoscopic approaches.

Inverted Papilloma Ooriginating from the Opticocarotid Recess

Objective: 1) Understand the relationship of the opticocarotid recess with the surrounding structures. 2) Explain the pathophysiology and natural history of an inverting papilloma (IP) in the sphenoid sinus. 3) Examine the significance of a neoplasm originating from the anterior clinoid. Method: This case report was conducted in a tertiary hospital setting in June 2011. The subject, a 49-year-old woman, presented with an inverting papilloma originating from the opticocarotid recess causing optic nerve dehiscence. The intervention was endoscopic excision. Outcome was measured by clinical examination, and follow-up patient analysis is ongoing. Results: The patient was found to have an inverting papilloma (IP) of the sphenoid sinus. During endoscopic sinus surgery, the inverted papilloma was visualized originating from the sphenoid sinus and causing bony erosion in the area of the opticocarotid recess. An area of optic nerve dehiscence was identified, and the sheath of the optic nerve was clearly visualized once the tumor was peeled off the optic canal. Pathology confirmed the diagnosis of inverting papilloma and was negative for carcinoma. Follow-up clinical examination of the patient revealed that endoscopic excision effectively removed the neoplasm without local complications or recurrence. Conclusion: Inverting papillomas originating from the region of the opticocarotid recess are an atypical entity and have the potential to cause rare, but serious, complications. The authors are unaware of any reported cases of an IP originating from this area. Early, effective management is crucial given the vital structures at risk.

Monocular Vision Loss and Headache in a 60-Year-Old Liver Transplant Patient

Monocular Vision Loss and Headache in a 60-Year-Old Liver Transplant Patient

Anatomical aspects in the transsphenoidal–transethmoidal approach to the optic canal: An anatomic–cadaveric study

BackgroundDetermining anatomic landmarks during a transsphenoidal–transethmoidal approach to the optic canal region is of critical importance. MethodsSella–parasella sphenoid bone blocks were extracted from adult cadavers. Anatomic dissections were performed in the optic canal region using a surgical microscope in 30 samples. Quantitative measurements were done using photographic techniques. For histological evaluation, coronal and longitudinal cross-sections were taken from the bilateral optic canal in seven decalcified samples. ResultsOptic protuberance (OP), carotid protuberance (CP), medial opticocarotid recess (MOCR) and lateral opticocarotid recess (LOCR) were defined as lateral landmarks determining the width of the opening in the extended transsphenoidal–transethmoidal approach. Among all anatomic markers, LOCR was the most determinant lateral marker with tubercular recess the most prominent central marker. OPs showing the optic canal direction and inter-recessal sulci had similar distinguishing rates in the sphenoid sinus base. Inter-recessal sulci formed by OPs and CPs were observed between MOCR and LOCR in most samples. In histologic sections, the dural sheath was thicker inferolaterally to the optic nerve compared to superiorly and medially; collagen arrangement was dense and irregular. ConclusionAlthough LOCRs and tubercular recesses are safe and prominent markers in extended transsphenoidal–transethmoidal approaches, other anatomic markers should also be taken into consideration to perform an efficient optic canal approach and optic canal decompression. Other factors for safe dissection are the length of the optic canal, bone thickness, adherence of dural structures and the course of the intradural ophthalmic artery.

Anatomical landmarks for transnasal endoscopic skull base surgery

Resection of midline skull base lesions involve approaches needing extensive neurovascular manipulation. Transnasal endoscopic approach (TEA) is minimally invasive and ideal for certain selected lesions of the anterior skull base. A thorough knowledge of endonasal endoscopic anatomy is essential to be well versed with its surgical applications and this is possible only by dedicated cadaveric dissections. The goal in this study was to understand endoscopic anatomy of the orbital apex, petrous apex and the pterygopalatine fossa. Six cadaveric heads (3 injected and 3 non injected) and 12 sides, were dissected using a TEA outlining systematically, the steps of surgical dissection and the landmarks encountered. Dissection done by the "2 nostril, 4 hands" technique, allows better transnasal instrumentation with two surgeons working in unison with each other. The main surgical landmarks for the orbital apex are the carotid artery protuberance in the lateral sphenoid wall, optic nerve canal, lateral optico-carotid recess, optic strut and the V2 nerve. Orbital apex includes structures passing through the superior and inferior orbital fissure and the optic nerve canal. Vidian nerve canal and the V2 are important landmarks for the petrous apex. Identification of the sphenopalatine artery, V2 and foramen rotundum are important during dissection of the pterygopalatine fossa. In conclusion, the major potential advantage of TEA to the skull base is that it provides a direct anatomical route to the lesion without traversing any major neurovascular structures, as against the open transcranial approaches which involve more neurovascular manipulation and brain retraction. Obviously, these approaches require close cooperation and collaboration between otorhinolaryngologists and neurosurgeons.

The Medial Opticocarotid Recess: An Endoscopic Keyhole to the Ventral Cranial Base

Objective: The medial opticocarotid recess (MOCR) is an important landmark for expanded endonasal endoscopic approaches. The goal of this study was to examine the anatomical features of this structure and understand its role as a keyhole for endoscopic approaches to the cranial base.

Endoscopic Orientation of the Parasellar Region in Sphenoid Sinus with Ill-Defined Bony Landmarks: An Anatomic Study

The sphenoid bony landmarks are important for endoscopic orientation in skull base surgery but show a wide range of variations. We aimed to describe an instructional model for the endoscopic parasellar anatomy in sphenoid sinuses with ill-defined bony landmarks. Five preserved injected cadaveric heads and four sides of dry skulls were studied endoscopically via transethmoid, transsphenoidal approach. The parasellar region was exposed by drilling along the maxillary nerve (V2) canal [the length of the foramen rotundum (FR) between the middle cranial fossa and the pterygopalatine fossa]. This was achieved by drilling in the inferior part of the lateral wall of posterior ethmoids immediately above the sphenopalatine foramen. Cavernous V2 was traced to the paraclival internal carotid artery (ICA). Cavernous sinus (CS) apex was exposed by drilling a triangle bounded by V2 and its canal inferiorly, bone between FR and superior orbital fissure (SOF) anteriorly, and ophthalmic nerve (V1) superiorly. Drilling was continued toward the annulus of Zinn (AZ) and optic nerve superiorly and over the intracavernous ICA posteriorly. Endoscopic measurements between V2, SOF, AZ, and opticocarotid recess were obtained. Endoscopic systematic orientation of parasellar anatomy is presented that can be helpful for approaching sphenoid sinus with ill-defined bony landmarks.

Endoscopic Endonasal Trans-sphenoidal Optic Nerve Decompression for Traumatic Optic Neuropathy -Technical Note-

The endoscopic endonasal trans-sphenoidal approach can decompress the traumatized and swollen optic nerve without brain retraction. Three cases of traumatic optic neuropathy (TON) were treated by this endoscopic approach. We performed 58 endoscopic endonasal trans-sphenoidal approaches in 52 patients between April 2006 and December 2007. Three patients, 2 men and a woman aged 42-66 years, with TON were treated by endoscopic endonasal trans-sphenoidal optic nerve decompression. Adequate decompression of the optic canal was observed in all three patients. Two experienced improved visual function, but the third did not. No surgical complications were observed in any patient. We were able to reach the optic canal above the opticocarotid recess near the orbit. Endoscopic endonasal trans-sphenoidal optic canal decompression using a navigation system may be a safe and effective surgical strategy in carefully selected patients with TON.

CT virtual endoscopy for transsphenoidal microsurgical treatment of pituitary microadenomas

Objective To evaluate the value of CT virtual endoscopy(CTVE)for microsurgery of pituitary microadenomas via transsphenoidal approach.Methods In 18 patients with pituitary micmadenomas underwent microsurgery via transsphenoidal approach,the presurgical CT data was transfered to work station,the anatomies of the sphenoid sinus were then reconstructed by CTVE.The CTVE images were used to make the preoperative planning and indentify sphenoid sinus, sellar floor,and the position of the tumor during surgery.The CTVE images and the views from intraoperative microscope were compared. Results CTVE could display the anotomoties of sphenoid sinus in a three-dimentional mode.The display rates of superfical antomies such as sphenoid septa,sellar floor,carotid prominence,optic prominence and opticocarotid recess were 344.4%,100%,41.7%,36.1%and 58.3%respectively and the visual fields of these anatomic landmarks were larger than the views from the intraoperative microscope. CTVE could depcit the anatomies of the enhanced carotid ateries and pituitary tissue and some optic canals underlying the sellae by transparent function or heighten the threshold.The sites of the tumor could be marked correctly on CTVE images.CTVE could simulate the operative approach and some operating procedures properatively. Conclusion CTVE can display the anatomies of sphenoid sinus in a three-dimensional mode. In transsphenoidal treatment of pituitary microadenoma,CTVE can help to make preoperative planning,locate the intraoperative structures and make a precise bone window during surgery. Key words: CT virtual endoscopy; Microsurgical operation; Transsphenoidal approach; Pituitary; Microadenomas

Transsphenoidal Optic Nerve Decompression

The objective was to study the relationships among the optic nerve, posterior paranasal sinuses, and ophthalmic artery. The identification of reliable anatomic landmarks would provide an endoscopic anatomic basis for optic nerve localization and effective prevention of ophthalmic artery injury during transsphenoidal optic nerve decompression surgery. The Messerklinger technique was performed to open the posterior ethmoid sinus and sphenoid sinus in 8 adult-head specimens. The opticocarotid recess and optic canal were identified under endoscopy, and the relationships between the optic nerve and posterior paranasal sinuses were observed. The relationship between the optic nerve and ophthalmic artery was examined. In all specimens, the opticocarotid recess could be identified; however, the optic nerve protuberance was present in only 10 sides (62%). Three types of relationships were found to exist among the optic nerve, sphenoid sinus, and posterior ethmoid sinus. The posterior ethmoid sinus was anterior and the sphenoid sinus was posterior in 8 sides (50%), the sphenoid sinus was both anterior and posterior in 5 sides (31%), and the ethmoid sinus was both anterior and posterior in 3 sides (19%). At the intracranial opening of the optic canal, the ophthalmic artery was inferomedial to the optic nerve in 9 sides (56%), inferior to the optic nerve in 4 sides (25%), and inferolateral to the optic nerve in 3 sides (19%). The ophthalmic artery coursed laterally from inferior to the optic nerve, and at the intraorbital opening of the optic canal, the ophthalmic artery was inferolateral to the optic nerve in 13 sides (81%) and inferior to the optic nerve in 3 sides (19%). The opticocarotid recess is always present; the imaging characteristics of endoscopy allow this recess to be more reliably identified than the optic nerve protuberance. It can be used as the anatomic landmark of choice in endoscopic optic nerve decompression. The origin of the ophthalmic artery is inferomedial to the optic nerve, and thereafter, it courses inferolaterally. An intersecting relationship exists along its course, a factor that must be taken into account during surgery to avoid injuring the ophthalmic artery.

Endoscopic and Microsurgical Anatomy of the Opticocarotid Recess of the Sphenoid Sinus Applied to Endoscopic Transnasal Skull Base Surgery

Endoscopic and Microsurgical Anatomy of the Opticocarotid Recess of the Sphenoid Sinus Applied to Endoscopic Transnasal Skull Base Surgery