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Ricardo L Carrau - One of the best experts on this subject based on the ideXlab platform.
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characterization and implications of the lingual process of the sphenoid bone a cadaveric and radiographic study
International Forum of Allergy & Rhinology, 2020Co-Authors: Daniel M Prevedello, Nyall R London, Xiaohong Chen, Ricardo L CarrauAbstract:BACKGROUND The surgical significance of the lingual process of the sphenoid bone (LPSB) has not been sufficiently addressed. The purpose of this study was to describe the anatomical details of the LPSB in relation to the Quadrangular Space. Moreover, the incidence of the LPSB and its correlation with the pneumatization of the sphenoid sinus and the development of the lateral recess of the sphenoid sinus (LRSS) were also evaluated. METHODS A dissection and exposure of the LPSB and the Quadrangular Space was performed on 10 cadaveric specimens (20 sides). The incidence, length, and height of the LPSB were also assessed on computed tomography (CT) images (60 patients, 120 sides). The association between the presence of the LPSB with the pneumatization type of the sphenoid sinus and the presence of a LRSS was evaluated. RESULTS In a cadaveric model, the LPSB, in association with the petrolingual ligament extending from the LPSB to the petrous apex, was identified on 7 sides (35%). The LPSB was continuous with the mandibular strut. The overall incidence of a LPSB was 48.33% on CT images, and the average length and height of the LPSB was (mean ± standard deviation) 5.30 ± 1.44 mm and 6.51 ± 1.32 mm, respectively. A significant correlation was identified between presence of the LPSB with the pneumatization type of the sphenoid sinus (p = 0.004) but no correlation was identified with the presence of the LRSS (p = 0.071). CONCLUSION The LPSB and the petrolingual ligament are useful landmarks for procedures in the Quadrangular Space and Meckel's cave. However, the LPSB is not consistently present.
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Anatomical nuances of the internal carotid artery in relation to the Quadrangular Space
Journal of neurosurgery, 2017Co-Authors: Ricardo Landini Lutaif Dolci, Smita Upadhyay, Lamia Buohliqah, Daniel M Prevedello, Leo F. S. Ditzel Filho, Carlos R. Goulart, Paulo Roberto Lazarini, Ricardo L CarrauAbstract:OBJECTIVE The aim of this study was to evaluate the anatomical variations of the internal carotid artery (ICA) in relation to the Quadrangular Space (QS) and to propose a classification system based on the results. METHODS A total of 44 human cadaveric specimens were dissected endonasally under direct endoscopic visualization. During the dissection, the anatomical variations of the ICA and their relationship with the QS were noted. RESULTS The Space between the paraclival ICAs (i.e., intercarotid Space) can be classified as 1 of 3 different shapes (i.e., trapezoid, square, or hourglass) based on the trajectory of the ICAs. The ICA trajectories also directly influence the volumetric area of the QS. Based on its geometry, the QS was classified as one of the following: 1) Type A has the smallest QS area and is associated with a trapezoid intercarotid Space, 2) Type B corresponds to the expected QS area (not minimized or enlarged) and is associated with a square intercarotid Space, and 3) Type C has the largest QS area and is associated with an hourglass intercarotid Space. CONCLUSIONS The different trajectories of the ICAs can modify the area of the QS and may be an essential parameter to consider for preoperative planning and defining the most appropriate corridor to reach Meckel's cave. In addition, ICA trajectories should be considered prior to surgery to avoid injuring the vessels.
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Endoscopic endonasal study of the cavernous sinus and Quadrangular Space: Anatomic relationships.
Head & neck, 2016Co-Authors: Ricardo L L Dolci, Smita Upadhyay, Leo F S Ditzel Filho, Mariano E Fiore, Lamia Buohliqah, Paulo R Lazarini, Daniel M Prevedello, Ricardo L CarrauAbstract:The Quadrangular Space permits an anterior entry into Meckel's cave while obviating the need for cerebral or cranial nerve retraction. This avenue is intimately associated with the cavernous sinus; thus, from this ventral perspective, it is feasible to visualize the anteromedial, anterolateral, and Parkinson triangles. Twenty middle cranial fossae were dissected endonasally under direct endoscopic visualization. Measurements of the surface area of the Quadrangular Space and the ventrally accessible cavernous sinus triangles were performed using 3 coordinates under image-guided navigation. The surface area of the Quadrangular Space was 16.36 mm(2) (±2.89 mm(2) ). The anterolateral triangle was the largest (47.27 ± 5.37 mm(2) ), whereas Parkinson's was the smallest (22.46 ± 5.54 mm(2) ); the anteromedial triangle presented an average surface area 36.07 mm(2) (±4.15 mm(2) ). The trajectory of the internal carotid artery (ICA) significantly impacts the Quadrangular Space area and may be a potential parameter for defining the feasibility of this corridor. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1680-E1687, 2016. © 2016 Wiley Periodicals, Inc.
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The front door to meckel's cave: an anteromedial corridor via expanded endoscopic endonasal approach- technical considerations and clinical series.
Neurosurgery, 2009Co-Authors: Amin B Kassam, Daniel M Prevedello, Ricardo L Carrau, Carl H Snyderman, Shigeyuki Osawa, Askin Seker, Paul A. Gardner, Albert L RhotonAbstract:OBJECTIVE: Tumors within Meckel's cave are challenging and often require complex approaches. In this report, an expanded endoscopic endonasal approach is reported as a substitute for or complement to other surgical options for the treatment of various tumors within this region. METHODS: A database of more than 900 patients who underwent the expanded endoscopic endonasal approach at the University of Pittsburgh Medical Center from 1998 to March of 2008 were reviewed. From these, only patients who had an endoscopic endonasal approach to Meckel's cave were considered. The technique uses the maxillary sinus and the pterygopalatine fossa as part of the working corridor. Infraorbital/V 2 and the vidian neurovascular bundles are used as surgical landmarks. The Quadrangular Space is opened, which is bound by the internal carotid artery medially and inferiorly, V 2 laterally, and the abducens nerve superiorly. This offers direct access to the anteroinferomedial segment of Meckel's cave, which can be extended through the petrous bone to reach the cerebellopontine angle. RESULTS: Forty patients underwent an endoscopic endonasal approach to Meckel's cave. The most frequent abnormalities encountered were adenoid cystic carcinoma, meningioma, and schwannomas. Meckel's cave and surrounding structures were accessed adequately in all patients. Five patients developed a new facial numbness in at least 1 segment of the trigeminal nerve, but the deficit was permanent in only 2. Two patients had a transient Vlth cranial nerve palsy. Nine patients (30%) showed improvement of preoperative deficits on Cranial Nerves III to VI. CONCLUSION: In selected patients, the expanded endoscopic endonasal approach to the Quadrangular Space provides adequate exposure of Meckel's cave and its vicinity, with low morbidity.
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The Front Door to Meckel's Cave: An Anteromedial Corridor via Expanded Endoscopic Endonasal Approach—Technical Considerations and Clinical Series
Operative Neurosurgery, 2009Co-Authors: Amin B Kassam, Daniel M Prevedello, Ricardo L Carrau, Carl H Snyderman, Paul Gardner, Shigeyuki Osawa, Askin Seker, Albert L RhotonAbstract:Abstract Objective: Tumors within Meckel's cave are challenging and often require complex approaches. In this report, an expanded endoscopic endonasal approach is reported as a substitute for or complement to other surgical options for the treatment of various tumors within this region. Methods: A database of more than 900 patients who underwent the expanded endoscopic endonasal approach at the University of Pittsburgh Medical Center from 1998 to March of 2008 were reviewed. From these, only patients who had an endoscopic endonasal approach to Meckel's cave were considered. The technique uses the maxillary sinus and the pterygopalatine fossa as part of the working corridor. Infraorbital/V2 and the vidian neurovascular bundles are used as surgical landmarks. The Quadrangular Space is opened, which is bound by the internal carotid artery medially and inferiorly, V2 laterally, and the abducens nerve superiorly. This offers direct access to the anteroinferomedial segment of Meckel's cave, which can be extended through the petrous bone to reach the cerebellopontine angle. Results: Forty patients underwent an endoscopic endonasal approach to Meckel's cave. The most frequent abnormalities encountered were adenoid cystic carcinoma, meningioma, and schwannomas. Meckel's cave and surrounding structures were accessed adequately in all patients. Five patients developed a new facial numbness in at least 1 segment of the trigeminal nerve, but the deficit was permanent in only 2. Two patients had a transient Vlth cranial nerve palsy. Nine patients (30%) showed improvement of preoperative deficits on Cranial Nerves III to VI. Conclusion: In selected patients, the expanded endoscopic endonasal approach to the Quadrangular Space provides adequate exposure of Meckel's cave and its vicinity, with low morbidity.
Peter Gloviczki - One of the best experts on this subject based on the ideXlab platform.
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Quadrilateral Space Syndrome
Mayo Clinic proceedings, 2015Co-Authors: Sherry-ann Brown, Derrick A. Doolittle, Carol J. Bohanon, Arjun Jayaraj, Sailendra Naidu, Eric A. Huettl, Kevin J. Renfree, Gustavo S. Oderich, Haraldur Bjarnason, Peter GloviczkiAbstract:Quadrilateral Space syndrome (QSS) arises from compression or mechanical injury to the axillary nerve or the posterior circumflex humeral artery (PCHA) as they pass through the quadrilateral Space (QS). Quadrilateral Space syndrome is an uncommon cause of paresthesia and an underdiagnosed cause of digital ischemia in overhead athletes. Quadrilateral Space syndrome can present with neurogenic symptoms (pain and weakness) secondary to axillary nerve compression. In addition, repeated abduction and external rotation of the arm is felt to lead to injury of the PCHA within the QSS. This often results in PCHA thrombosis and aneurysm formation, with distal emboli. Because of relative infrequency, QSS is rarely diagnosed on evaluation of athletes with such symptoms. We report on 9 patients who presented at Mayo Clinic with QSS. Differential diagnosis, a new classification system, and the management of QSS are discussed, with a comprehensive literature review. The following search terms were used on PubMed: axillary nerve, posterior circumflex humeral artery, quadrilateral Space, and Quadrangular Space. Articles were selected if they described patients with symptoms from axillary nerve entrapment or PCHA thrombosis, or if related screening or imaging methods were assessed. References available within the obtained articles were also pursued. There was no date or language restriction for article inclusion; 5 studies in languages besides English were reported in German, French, Spanish, Turkish, and Chinese. a 2015 Mayo Foundation for Medical Education and Research n Mayo Clin Proc. 2015;nn(n):1-13 From the Department of Medicine (S.-A.N.B.), Department of Radiology (D.A.D.), Division of Vascular Medicine (C.J.B., W.E.W., I.R.M.), Division of Vascular Surgery (A.J., G.S.O., P.G.), and Division of Vascular and Interventional Radiology (H.B., I.R.M.), Mayo Clinic, Rochester, MN; and Division of Vascular and Interventional Radiology (S.G.N., E.A.H.) and Department of Orthopedic Surgery (K.J.R.), Mayo Clinic, Scottsdale, AZ. Q uadrilateral Space syndrome (QSS) arises from compression or mechanical injury to the axillary nerve (neurogenic quadrilateral Space syndrome [nQSS]) and/or posterior circumflex humeral artery (PCHA) (vascular quadrilateral Space syndrome [vQSS]) as they pass through the quadrilateral Space (QS). The QS is bounded by the edge of the long head of the triceps medially, the medial edge of the surgical neck of the humerus laterally, the tendon of the teres major and latissimus dorsi muscles inferiorly, and the teres minor muscle or the scapulohumeral capsule superiorly (Supplemental Figure 1, available online at http://www.mayoclinicproceedings.org). The term QSS was first coined by Cahill in 1980 and then again in 1983 in a subsequent article describing several patients with axillary Mayo Clin Proc. n XXX 2015;nn(n):1-13 n http://dx.doi.org/10.1016 www.mayoclinicproceedings.org n a 2015 Mayo Foundation for M nerve compression. McCarthy et al later reported partial occlusion of the PCHA in a baseball pitcher, with distal embolization to the right third digit, felt to be due to PCHA injury within the QS. Subsequently, QSS has been reported most commonly in overhead or “throwing” athletes in sports that heavily involve abduction and external rotation (AER), including volleyball, baseball, and swimming. Quadrilateral Space syndrome has also been associated with other activities with frequent AER, such as yoga or window cleaning. Patients with QSS manifest with various symptoms (Figure 1). Neurogenic manifestations may include nondermatomal neuropathic pain, numbness, and weakness in the shoulder (usually posterior), often radiating down the arm. Vascular manifestations may /j.mayocp.2014.12.012 edical Education and Research 1
Frank A. Liporace - One of the best experts on this subject based on the ideXlab platform.
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Unusual anatomic variant of the axillary nerve challenging the deltopectoral approach to the shoulder: a case report
Patient Safety in Surgery, 2019Co-Authors: Richard A. Pizzo, Jeffrey Lynch, Donald M. Adams, Richard S. Yoon, Frank A. LiporaceAbstract:Background The deltopectoral approach is a well-described surgical approach to the proximal humerus and glenohumeral joint. One of the structures at risk during this approach is the axillary nerve. Typically, the axillary nerve arises off the posterior cord of the brachial plexus and courses lateral to the proximal humerus and inferior to the glenohumeral joint, exiting the axilla through the Quadrangular Space. We describe a case of an aberrant axillary nerve, coursing anteriorly across the glenohumeral joint within the deltopectoral groove encountered during a reverse total shoulder arthroplasty.
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Unusual anatomic variant of the axillary nerve challenging the deltopectoral approach to the shoulder: a case report
BMC, 2019Co-Authors: Richard A. Pizzo, Jeffrey Lynch, Donald M. Adams, Richard S. Yoon, Frank A. LiporaceAbstract:Abstract Background The deltopectoral approach is a well-described surgical approach to the proximal humerus and glenohumeral joint. One of the structures at risk during this approach is the axillary nerve. Typically, the axillary nerve arises off the posterior cord of the brachial plexus and courses lateral to the proximal humerus and inferior to the glenohumeral joint, exiting the axilla through the Quadrangular Space. We describe a case of an aberrant axillary nerve, coursing anteriorly across the glenohumeral joint within the deltopectoral groove encountered during a reverse total shoulder arthroplasty. Case presentation A 73-year-old female presented complaining of atraumatic progressive right shoulder pain of several months duration. Clinical and radiographic findings were consistent with advanced rotator cuff arthropathy. After failing appropriate non-operative treatment, the patient elected to undergo reverse total shoulder arthroplasty. During the deltopectoral approach to the glenohumeral joint, the axillary nerve was found to be coursing deep to the cephalic vein within the deltopectoral interval. The nerve was isolated and protected, and the glenohumeral joint was accessed via a small window in the anterior deltoid muscle. The remainder of the procedure was performed without complication. The patient was found to be healing well and with normal axillary nerve function at 4-month follow-up. Conclusions Neurologic lesions are well-documented complications of reverse total shoulder arthroplasty. The integrity of the axillary nerve is of particular importance to reverse total shoulder arthroplasty as it innervates the deltoid and post-operative function of the extremity is dependent upon a functioning deltoid muscle. Extreme care must be taken to avoid insult to the axillary nerve and any aberrant paths it may course around the glenohumeral joint
Daniel M Prevedello - One of the best experts on this subject based on the ideXlab platform.
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characterization and implications of the lingual process of the sphenoid bone a cadaveric and radiographic study
International Forum of Allergy & Rhinology, 2020Co-Authors: Daniel M Prevedello, Nyall R London, Xiaohong Chen, Ricardo L CarrauAbstract:BACKGROUND The surgical significance of the lingual process of the sphenoid bone (LPSB) has not been sufficiently addressed. The purpose of this study was to describe the anatomical details of the LPSB in relation to the Quadrangular Space. Moreover, the incidence of the LPSB and its correlation with the pneumatization of the sphenoid sinus and the development of the lateral recess of the sphenoid sinus (LRSS) were also evaluated. METHODS A dissection and exposure of the LPSB and the Quadrangular Space was performed on 10 cadaveric specimens (20 sides). The incidence, length, and height of the LPSB were also assessed on computed tomography (CT) images (60 patients, 120 sides). The association between the presence of the LPSB with the pneumatization type of the sphenoid sinus and the presence of a LRSS was evaluated. RESULTS In a cadaveric model, the LPSB, in association with the petrolingual ligament extending from the LPSB to the petrous apex, was identified on 7 sides (35%). The LPSB was continuous with the mandibular strut. The overall incidence of a LPSB was 48.33% on CT images, and the average length and height of the LPSB was (mean ± standard deviation) 5.30 ± 1.44 mm and 6.51 ± 1.32 mm, respectively. A significant correlation was identified between presence of the LPSB with the pneumatization type of the sphenoid sinus (p = 0.004) but no correlation was identified with the presence of the LRSS (p = 0.071). CONCLUSION The LPSB and the petrolingual ligament are useful landmarks for procedures in the Quadrangular Space and Meckel's cave. However, the LPSB is not consistently present.
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Anatomical nuances of the internal carotid artery in relation to the Quadrangular Space
Journal of neurosurgery, 2017Co-Authors: Ricardo Landini Lutaif Dolci, Smita Upadhyay, Lamia Buohliqah, Daniel M Prevedello, Leo F. S. Ditzel Filho, Carlos R. Goulart, Paulo Roberto Lazarini, Ricardo L CarrauAbstract:OBJECTIVE The aim of this study was to evaluate the anatomical variations of the internal carotid artery (ICA) in relation to the Quadrangular Space (QS) and to propose a classification system based on the results. METHODS A total of 44 human cadaveric specimens were dissected endonasally under direct endoscopic visualization. During the dissection, the anatomical variations of the ICA and their relationship with the QS were noted. RESULTS The Space between the paraclival ICAs (i.e., intercarotid Space) can be classified as 1 of 3 different shapes (i.e., trapezoid, square, or hourglass) based on the trajectory of the ICAs. The ICA trajectories also directly influence the volumetric area of the QS. Based on its geometry, the QS was classified as one of the following: 1) Type A has the smallest QS area and is associated with a trapezoid intercarotid Space, 2) Type B corresponds to the expected QS area (not minimized or enlarged) and is associated with a square intercarotid Space, and 3) Type C has the largest QS area and is associated with an hourglass intercarotid Space. CONCLUSIONS The different trajectories of the ICAs can modify the area of the QS and may be an essential parameter to consider for preoperative planning and defining the most appropriate corridor to reach Meckel's cave. In addition, ICA trajectories should be considered prior to surgery to avoid injuring the vessels.
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Endoscopic endonasal study of the cavernous sinus and Quadrangular Space: Anatomic relationships.
Head & neck, 2016Co-Authors: Ricardo L L Dolci, Smita Upadhyay, Leo F S Ditzel Filho, Mariano E Fiore, Lamia Buohliqah, Paulo R Lazarini, Daniel M Prevedello, Ricardo L CarrauAbstract:The Quadrangular Space permits an anterior entry into Meckel's cave while obviating the need for cerebral or cranial nerve retraction. This avenue is intimately associated with the cavernous sinus; thus, from this ventral perspective, it is feasible to visualize the anteromedial, anterolateral, and Parkinson triangles. Twenty middle cranial fossae were dissected endonasally under direct endoscopic visualization. Measurements of the surface area of the Quadrangular Space and the ventrally accessible cavernous sinus triangles were performed using 3 coordinates under image-guided navigation. The surface area of the Quadrangular Space was 16.36 mm(2) (±2.89 mm(2) ). The anterolateral triangle was the largest (47.27 ± 5.37 mm(2) ), whereas Parkinson's was the smallest (22.46 ± 5.54 mm(2) ); the anteromedial triangle presented an average surface area 36.07 mm(2) (±4.15 mm(2) ). The trajectory of the internal carotid artery (ICA) significantly impacts the Quadrangular Space area and may be a potential parameter for defining the feasibility of this corridor. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1680-E1687, 2016. © 2016 Wiley Periodicals, Inc.
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The front door to meckel's cave: an anteromedial corridor via expanded endoscopic endonasal approach- technical considerations and clinical series.
Neurosurgery, 2009Co-Authors: Amin B Kassam, Daniel M Prevedello, Ricardo L Carrau, Carl H Snyderman, Shigeyuki Osawa, Askin Seker, Paul A. Gardner, Albert L RhotonAbstract:OBJECTIVE: Tumors within Meckel's cave are challenging and often require complex approaches. In this report, an expanded endoscopic endonasal approach is reported as a substitute for or complement to other surgical options for the treatment of various tumors within this region. METHODS: A database of more than 900 patients who underwent the expanded endoscopic endonasal approach at the University of Pittsburgh Medical Center from 1998 to March of 2008 were reviewed. From these, only patients who had an endoscopic endonasal approach to Meckel's cave were considered. The technique uses the maxillary sinus and the pterygopalatine fossa as part of the working corridor. Infraorbital/V 2 and the vidian neurovascular bundles are used as surgical landmarks. The Quadrangular Space is opened, which is bound by the internal carotid artery medially and inferiorly, V 2 laterally, and the abducens nerve superiorly. This offers direct access to the anteroinferomedial segment of Meckel's cave, which can be extended through the petrous bone to reach the cerebellopontine angle. RESULTS: Forty patients underwent an endoscopic endonasal approach to Meckel's cave. The most frequent abnormalities encountered were adenoid cystic carcinoma, meningioma, and schwannomas. Meckel's cave and surrounding structures were accessed adequately in all patients. Five patients developed a new facial numbness in at least 1 segment of the trigeminal nerve, but the deficit was permanent in only 2. Two patients had a transient Vlth cranial nerve palsy. Nine patients (30%) showed improvement of preoperative deficits on Cranial Nerves III to VI. CONCLUSION: In selected patients, the expanded endoscopic endonasal approach to the Quadrangular Space provides adequate exposure of Meckel's cave and its vicinity, with low morbidity.
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The Front Door to Meckel's Cave: An Anteromedial Corridor via Expanded Endoscopic Endonasal Approach—Technical Considerations and Clinical Series
Operative Neurosurgery, 2009Co-Authors: Amin B Kassam, Daniel M Prevedello, Ricardo L Carrau, Carl H Snyderman, Paul Gardner, Shigeyuki Osawa, Askin Seker, Albert L RhotonAbstract:Abstract Objective: Tumors within Meckel's cave are challenging and often require complex approaches. In this report, an expanded endoscopic endonasal approach is reported as a substitute for or complement to other surgical options for the treatment of various tumors within this region. Methods: A database of more than 900 patients who underwent the expanded endoscopic endonasal approach at the University of Pittsburgh Medical Center from 1998 to March of 2008 were reviewed. From these, only patients who had an endoscopic endonasal approach to Meckel's cave were considered. The technique uses the maxillary sinus and the pterygopalatine fossa as part of the working corridor. Infraorbital/V2 and the vidian neurovascular bundles are used as surgical landmarks. The Quadrangular Space is opened, which is bound by the internal carotid artery medially and inferiorly, V2 laterally, and the abducens nerve superiorly. This offers direct access to the anteroinferomedial segment of Meckel's cave, which can be extended through the petrous bone to reach the cerebellopontine angle. Results: Forty patients underwent an endoscopic endonasal approach to Meckel's cave. The most frequent abnormalities encountered were adenoid cystic carcinoma, meningioma, and schwannomas. Meckel's cave and surrounding structures were accessed adequately in all patients. Five patients developed a new facial numbness in at least 1 segment of the trigeminal nerve, but the deficit was permanent in only 2. Two patients had a transient Vlth cranial nerve palsy. Nine patients (30%) showed improvement of preoperative deficits on Cranial Nerves III to VI. Conclusion: In selected patients, the expanded endoscopic endonasal approach to the Quadrangular Space provides adequate exposure of Meckel's cave and its vicinity, with low morbidity.
Jerry W Oakes - One of the best experts on this subject based on the ideXlab platform.
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surgical anatomy of the axillary nerve within the Quadrangular Space
Journal of Neurosurgery, 2005Co-Authors: Shane R Tubbs, Alan C Aikens, Justin P Martin, Leslie L Weed, George E Salter, Elizabeth C Tylerkabara, Jerry W OakesAbstract:Object. There is a paucity of literature regarding the surgical anatomy of the Quadrangular Space (QS), which is a potential site of entrapment for the axillary nerve. Muscle hypertrophy of this geometrical area and fascial bands within it have been implicated in compression of the axillary nerve. Methods. Fifteen human cadavers (30 sides) were dissected for this study. Measurements of the QS and its contents were made. The mean height of this Space was 2.5 cm and the mean width 2.5 cm; its mean depth was 1.5 cm. The axillary nerve was always the most superior structure in the Space, and in all cases the nerve and artery hugged the surgical neck of the humerus just superior to the origin of the lateral head of the triceps brachii muscle. This arrangement placed the axillary nerve in the upper lateral portion of the QS in all cadaveric specimens. The nerve branched into its muscular components within this Space in 10 sides (33%) and posterior to it in 20 sides (66%). The cutaneous component of the axillary nerve branched from the main trunk of the nerve posterior to the QS in all specimens. Fascial bands were found in this Space in 27 (90%) of 30 sides. Conclusions. Knowledge of the anatomy of the QS may aid the surgeon who wishes to explore and decompress the axillary nerve within this geometrical confine.
