Carl Snyderman - Academia.edu (original) (raw)

Papers by Carl Snyderman

Research paper thumbnail of Feasibility and Safety Issues of Endoscopic Endonasal Surgery for Sinonasal Malignancy in Low Volume Center

Journal of neurological surgery, Mar 2, 2017

Research paper thumbnail of Surgical telementoring: A new model for surgical training

Laryngoscope, Mar 24, 2016

Objectives/Hypothesis: To assess the efficacy of a surgical telementoring program for endoscopic ... more Objectives/Hypothesis: To assess the efficacy of a surgical telementoring program for endoscopic skull base surgery. Study Design: Prospective case series with surveys of surgeons. Methods: A surgical telementoring program was established for mentoring of a skull base team at the University of Maribor in Slovenia by an experienced skull base team at the University of Pittsburgh Medical Center in Pennsylvania. Two-way video and audio streaming provided real-time communication with the surgical team. Over a period of 3 years, 10 endoscopic endonasal surgeries of the skull base were mentored preoperatively and during the key part of the procedure. Following each procedure, an evaluation form was used to document the mentoring interventions and rate the experience. Results: Procedures included endoscopic endonasal approaches to the sella, anterior cranial fossa, posterior cranial fossa, and orbit. Diagnoses included benign and malignant neoplasms, cerebrospinal fluid leak, and inflammatory disease. In nine of 10 cases, adequate audio and video communications were maintained. The most frequent mentoring interventions were for identification of anatomy, extent of exposure, extent of resection, and surgical technique. The median perceived value by the junior surgical team was 9.5 (range 8-10). A model for surgical telementoring is proposed. Conclusion: Surgical telementoring provides the ability to help surgeons develop their surgical skills to a greater level of proficiency for complex surgeries when experienced mentors are not available locally. The technology is reliable and available at most institutions. Perceived benefits of surgical telementoring include improved surgical exposure, increased extent of tumor resection, and decreased duration of surgery.

Research paper thumbnail of The Selective Role of Open and Endoscopic Approaches for Sinonasal Malignant Tumours

Research paper thumbnail of The expanded endoscopic endonasal approaches for the skull base

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA, 2018

Background: Endoscopic endonasal approach (EEA) for skull base surgery (SBS) is a significant mod... more Background: Endoscopic endonasal approach (EEA) for skull base surgery (SBS) is a significant modification of the current practice. Methods: We reviewed our experience at the University of Pittsburgh with EEAs for 800 patients from 1998 to July 2007. Results: Modular approaches to multiple pathologies of the skull base were designed totally based on intrinsic anatomy. Stages of training were established based on the level of technical difficulty and potential risk of vascular and neural injury. Five levels were defined in an incremental manner. Conclusions: Practice standardization with modular, incremental training is projected to facilitate the gaining of knowledge and skills to safely master EEAs for SBS in an organized manner. We suggest adherence to the systematic acquisition of endoscopic skills, to work as an integrated team of surgeons and to have a thorough perspective of conventional SBS and endoscopic surgery. Therefore, the choice of approach must be a specific function ...

Research paper thumbnail of Endoscopic endonasal surgery for epidermoid and dermoid cysts: a 10-year experience

Journal of Neurosurgery, 2018

OBJECTIVEEpidermoid and dermoid cysts may be found along the cranial base and are commonly resect... more OBJECTIVEEpidermoid and dermoid cysts may be found along the cranial base and are commonly resected via open transcranial approaches. The use of endoscopic endonasal approaches for resection of these tumors has been rarely reported.METHODSThe authors retrospectively reviewed the medical records of 21 patients who underwent endoscopic endonasal surgery for epidermoid and dermoid cyst resection at the University of Pittsburgh Medical Center between January 2005 and June 2014. Surgical outcomes and variables that might affect the extent of resection and complications were analyzed.RESULTSTotal resection (total removal of cyst contents and capsule) was achieved in 8 patients (38.1%), near-total resection (total removal of cyst contents, incomplete removal of cyst capsule) in 9 patients (42.9%), and subtotal resection (incomplete removal of cyst contents and capsule) in 4 patients (19%). Larger cyst volume (≥ 3 cm3) and intradural location (15 cysts) were significantly associated with no...

Research paper thumbnail of Endoscopic Endonasal Surgery of the Skull Base: Training and Quality Assurance Model for Low-Volume Centers

Journal of Neurological Surgery Part B: Skull Base, 2017

Research paper thumbnail of Extended Endoscopic Endonasal Approach to the Anterior and Central Skull Base: Training and Quality Assurance Model for Low-Volume Centers

Journal of Neurological Surgery Part B: Skull Base, 2016

Research paper thumbnail of Development of a Skull Base Center in a Low-Volume Environment

Journal of Neurological Surgery Part B: Skull Base, 2016

Research paper thumbnail of Reconstruction of the cranial base after endonasal skull base surgery: Local tissue flaps

Operative Techniques in Otolaryngology-Head and Neck Surgery, 2010

Advances in endoscopic techniques and technology have substantially increased the scope of endona... more Advances in endoscopic techniques and technology have substantially increased the scope of endonasal skull base surgery. Large dural defects after expanded endonasal approaches (EEA) present a challenge for reconstruction and have revealed the limitations of conventional reconstructive methods. Initial reconstructive attempts using nonvascularized free tissue grafts resulted in unacceptably high rates of cerebrospinal fluid fistulae. The advent of vascularized, pedicled flaps has substantially improved these outcomes. These flaps also have the advantage of a large surface area and can be mobilized over a large arc of rotation. Vascularized tissue heals quickly and can tolerate postoperative radiation therapy. We have developed 3 nasal vascularized flaps that can be used for skull base reconstruction after EEA. The anatomy, technique, and reconstructive considerations for the nasoseptal flap, the inferior turbinate flap, and the middle turbinate flap will be reviewed in detail in the following report.

Research paper thumbnail of Endonasal surgery of the ventral skull base--endoscopic transcranial surgery

Oral and maxillofacial surgery clinics of North America, 2010

Skull base surgery is evolving from traditional transfacial and transcranial approaches to the en... more Skull base surgery is evolving from traditional transfacial and transcranial approaches to the endoscopic endonasal approach, a less intrusive corridor for accessing the ventral skull base. This technique eliminates facial scars, expedites recovery, and obviates brain retraction. The goals of surgical excision, whether palliative or curative, are identical: an approach that is less disruptive to normal tissues. By exploiting the sinonasal corridor, the entire ventral skull base may be accessed to successfully treat benign and malignant lesions. The expanding limits of endoscopic skull base surgery have been accompanied by commensurate innovations in reconstructive techniques that are reliable and have been shown to limit postoperative complications. This article describes the basis for this approach and provides the latest outcome data supporting the current state of the art for endoscopic skull base surgery.

Research paper thumbnail of Combined endoscopic endonasal transorbital approach with transconjunctival-medial orbitotomy for excisional biopsy of the optic nerve: technical note

Journal of neurological surgery reports, 2012

Background Access to the intraorbital optic nerve segment can be facilitated via a transcranial a... more Background Access to the intraorbital optic nerve segment can be facilitated via a transcranial approach that allows access to the entire orbital cavity. The endoscopic endonasal approach (EEA) combined with a transconjunctival-medial orbitotomy represents an alternative technique to achieve the same goal. Objective Report a surgical technique that allows total resection of the intraorbital optic nerve with minimal trauma and excellent results. Further extend and define the limits and indications of the EEA to orbital surgery. Methods A patient with rapidly progressive, but asymmetric, vision loss underwent EEA for optic nerve biopsy. Due to the undetermined histopathological diagnosis and complete unilateral vision loss, diagnostic total optic nerve resection was indicated. The entire intraorbital length of the nerve was resected via an endoscopic endonasal transorbital approach combined with transconjunctival-medial orbitotomy. Results A 2-cm intraorbital nerve segment was sent fo...

Research paper thumbnail of Endoscopic Endonasal Pituitary Surgery: Patient and Societal Costs of Surgical Education

Journal of Neurological Surgery Part B: Skull Base, 2012

Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of th... more Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of the anterior skull base. The minimally invasive access through an eyelid incision involves dissection in normal tissue planes, preserves frontalis muscle fi bers, avoids injury to the fronto-temporal facial nerve branches, and heals with excellent cosmetic results.

Research paper thumbnail of Endoscopic endonasal skull base surgery in the pediatric population

Journal of Neurosurgery-Pediatrics, 2013

S kull base lesions comprise a range of pathologies of neural, mesenchymal, notochordal, vascular... more S kull base lesions comprise a range of pathologies of neural, mesenchymal, notochordal, vascular, and, sometimes, epithelial origin. Such lesions are relatively rare in children and are mostly benign. 40 However, benign tumors can grow to exert mass effect and cause significant morbidity. 4 In many of these cases, excision is mandatory for their management. Additionally, skull base trauma may result in rhinorrhea requiring surgical repair. Pathology and trauma to the anterior cranial base have historically been approached via craniofacial resections. Although variations on this technique exist, most invariably involve a craniotomy, a transfacial approach, or a combined craniofacial approach. 26,41,60,61 Deep lesions may require brain retraction, heightening the risk of frontal lobe edema, infection, pneumocephalus, and other complications. 24,26 These approaches in children pose at Endoscopic endonasal skull base surgery in the pediatric population Clinical article

Research paper thumbnail of Endoscopic Endonasal Transpterygoid Nasopharyngectomy

Research paper thumbnail of Combined Surgical Approaches for Skull Base Chordomas

Journal of Neurological Surgery Part B: Skull Base, 2012

Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of th... more Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of the anterior skull base. The minimally invasive access through an eyelid incision involves dissection in normal tissue planes, preserves frontalis muscle fi bers, avoids injury to the fronto-temporal facial nerve branches, and heals with excellent cosmetic results.

Research paper thumbnail of A Novel Reconstructive Technique After Endoscopic Expanded Endonasal Approaches: Vascular Pedicle Nasoseptal Flap

The Laryngoscope, 2006

Background: In patients with large dural defects of the anterior and ventral skull base after end... more Background: In patients with large dural defects of the anterior and ventral skull base after endonasal skull base surgery, there is a significant risk of a postoperative cerebrospinal fluid leak after reconstruction. Reconstruction with vascularized tissue is desirable to facilitate rapid healing, especially in irradiated patients.Methods: We developed a neurovascular pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium based on the nasoseptal artery, a branch of the posterior septal artery (Hadad‐Bassagasteguy flap [HBF]). A retrospective review of patients undergoing endonasal skull base surgery at the University of Rosario, Argentina, and the University of Pittsburgh Medical Center was performed to identify patients who were reconstructed with a vascularized septal mucosal flap.Results: Forty‐three patients undergoing endonasal cranial base surgery were repaired with the septal mucosal flap. Two patients with postoperative cerebrospinal fluid leaks (5%) were su...

Research paper thumbnail of Endoscopic endonasal dissection of the infratemporal fossa: Anatomic relationships and importance of eustachian tube in the endoscopic skull base surgery

The Laryngoscope, 2010

Endoscopic endonasal approaches to the pterygopalatine and infratemporal fossae are technically c... more Endoscopic endonasal approaches to the pterygopalatine and infratemporal fossae are technically challenging due to the complex anatomy of these areas. This project attempts to develop an anatomic and surgical model to enhance the understanding of these spaces from the endonasal endoscopic perspective. Eight pterygopalatine and infratemporal fossae were dissected in four adult human specimens in accordance with institutional protocols. All specimens were prepared with vascular injections using colored latex. Both the pterygopalatine and infratemporal fossae were accessed using a transpterygoid approach, which included a medial maxillectomy. Rod lens endoscopes (with 0°, 30°, and 45° lenses), surgical microscope, microsurgical and endoscopic instruments were used to complete the dissections. Endoscopic endonasal approaches provided adequate access to the pterygopalatine and infratemporal fossae. Dissection of the internal maxillary artery and its terminal branches, and detachment of the medial and lateral pterygoid muscles were critical steps to access deeper structures of the infratemporal fossa. The lateral pterygoid plate was the most useful landmark to locate foramen ovale, and the mandibular branch of the trigeminal nerve. The Eustachian tube, medial pterygoid plate, and styloid process were the most useful landmarks to locate parapharyngeal poststyloid structures (parapharyngeal segment of the internal carotid artery, internal jugular vein, cranial nerves IX and X). A medial maxillectomy coupled with a transpterygoid endoscopic approach, provides adequate access to the pterygopalatine and infratemporal fossae. The complex anatomy of the infratemporal fossa requires precise identification of surgical landmarks to assure preservation of neurovascular structures.

Research paper thumbnail of Endoscopic Endonasal Approach for Nonvestibular Schwannomas

Neurosurgery, 2011

BACKGROUND Nonvestibular schwannomas of the skull base often represent a challenge owing to their... more BACKGROUND Nonvestibular schwannomas of the skull base often represent a challenge owing to their anatomic location. With improved techniques in endoscopic endonasal skull base surgery, resection of various ventral skull base tumors, including schwannomas, has become possible. OBJECTIVE To assess the outcomes of using endoscopic endonasal approach (EEA) for nonvestibular schwannomas of the skull base. METHODS Seventeen patients operated on for skull base schwannomas by EEA at the University of Pittsburgh Medical Center from 2003 to 2009 were reviewed. RESULTS Three patients underwent combined approaches with retromastoid craniectomy (n = 2) and orbitopterional craniotomy (n = 1). Three patients underwent multistage EEA. The rest received a single EEA operation. Data on degree of resection were found for 15 patients. Gross total resection (n = 9) and near-total…

Research paper thumbnail of Endoscopic Reconstruction of the Cranial Base Using a Pedicled Nasoseptal Flap

Operative Neurosurgery, 2008

Objective:Reconstruction of the cranial base using vascularized tissue promotes rapid and complet... more Objective:Reconstruction of the cranial base using vascularized tissue promotes rapid and complete healing, thus avoiding complications caused by persistent communication between the cranial cavity and the sinonasal tract. The Hadad-Bassagasteguy flap (HBF), a neurovascular pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium based on the nasoseptal artery, seems to be advantageous for the reconstruction of the cranial base after endonasal cranial base surgeryMethods:We performed a retrospective review of patients who underwent endonasal cranial base surgery at the University of Pittsburgh Medical Center from January 30, 2006 to January 30, 2007, identifying patients who experienced reconstruction with a vascularized septal mucosal flap (HBF). We analyzed the demographic data, pathological characteristics, site and extent of resection, use of cerebrospinal fluid (CSF) diversion techniques, and outcome.Results:Seventy-five patients who underwent endonasal cranial ba...

Research paper thumbnail of Endoscopic Endonasal Resection of Anterior Cranial Base Meningiomas

Neurosurgery, 2008

OBJECTIVE The endonasal route may be feasible for the resection of anterior cranial base tumors t... more OBJECTIVE The endonasal route may be feasible for the resection of anterior cranial base tumors that abut the paranasal sinuses. There are several case reports and mixed case series discussing this approach. Other than pituitary adenomas, there is a lack of literature describing the outcomes of endonasal approaches for single-tumor types such as meningiomas. METHODS In this study, we describe our current endoscopic endonasal technique and demonstrate the feasibility of using it to access anterior cranial base meningiomas from the back wall of the frontal sinus to the sella and laterally to the region of the midorbit. After this discussion, which includes key technical considerations and nuances, we address safety and efficacy by reporting the outcomes of our early experience with endoscopic endonasal resection of 35 anterior cranial base meningiomas. RESULTS A total of 35 patients underwent endoscopic endonasal resection of anterior cranial base meningiomas from October 2002 to Octo...

Research paper thumbnail of Feasibility and Safety Issues of Endoscopic Endonasal Surgery for Sinonasal Malignancy in Low Volume Center

Journal of neurological surgery, Mar 2, 2017

Research paper thumbnail of Surgical telementoring: A new model for surgical training

Laryngoscope, Mar 24, 2016

Objectives/Hypothesis: To assess the efficacy of a surgical telementoring program for endoscopic ... more Objectives/Hypothesis: To assess the efficacy of a surgical telementoring program for endoscopic skull base surgery. Study Design: Prospective case series with surveys of surgeons. Methods: A surgical telementoring program was established for mentoring of a skull base team at the University of Maribor in Slovenia by an experienced skull base team at the University of Pittsburgh Medical Center in Pennsylvania. Two-way video and audio streaming provided real-time communication with the surgical team. Over a period of 3 years, 10 endoscopic endonasal surgeries of the skull base were mentored preoperatively and during the key part of the procedure. Following each procedure, an evaluation form was used to document the mentoring interventions and rate the experience. Results: Procedures included endoscopic endonasal approaches to the sella, anterior cranial fossa, posterior cranial fossa, and orbit. Diagnoses included benign and malignant neoplasms, cerebrospinal fluid leak, and inflammatory disease. In nine of 10 cases, adequate audio and video communications were maintained. The most frequent mentoring interventions were for identification of anatomy, extent of exposure, extent of resection, and surgical technique. The median perceived value by the junior surgical team was 9.5 (range 8-10). A model for surgical telementoring is proposed. Conclusion: Surgical telementoring provides the ability to help surgeons develop their surgical skills to a greater level of proficiency for complex surgeries when experienced mentors are not available locally. The technology is reliable and available at most institutions. Perceived benefits of surgical telementoring include improved surgical exposure, increased extent of tumor resection, and decreased duration of surgery.

Research paper thumbnail of The Selective Role of Open and Endoscopic Approaches for Sinonasal Malignant Tumours

Research paper thumbnail of The expanded endoscopic endonasal approaches for the skull base

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA, 2018

Background: Endoscopic endonasal approach (EEA) for skull base surgery (SBS) is a significant mod... more Background: Endoscopic endonasal approach (EEA) for skull base surgery (SBS) is a significant modification of the current practice. Methods: We reviewed our experience at the University of Pittsburgh with EEAs for 800 patients from 1998 to July 2007. Results: Modular approaches to multiple pathologies of the skull base were designed totally based on intrinsic anatomy. Stages of training were established based on the level of technical difficulty and potential risk of vascular and neural injury. Five levels were defined in an incremental manner. Conclusions: Practice standardization with modular, incremental training is projected to facilitate the gaining of knowledge and skills to safely master EEAs for SBS in an organized manner. We suggest adherence to the systematic acquisition of endoscopic skills, to work as an integrated team of surgeons and to have a thorough perspective of conventional SBS and endoscopic surgery. Therefore, the choice of approach must be a specific function ...

Research paper thumbnail of Endoscopic endonasal surgery for epidermoid and dermoid cysts: a 10-year experience

Journal of Neurosurgery, 2018

OBJECTIVEEpidermoid and dermoid cysts may be found along the cranial base and are commonly resect... more OBJECTIVEEpidermoid and dermoid cysts may be found along the cranial base and are commonly resected via open transcranial approaches. The use of endoscopic endonasal approaches for resection of these tumors has been rarely reported.METHODSThe authors retrospectively reviewed the medical records of 21 patients who underwent endoscopic endonasal surgery for epidermoid and dermoid cyst resection at the University of Pittsburgh Medical Center between January 2005 and June 2014. Surgical outcomes and variables that might affect the extent of resection and complications were analyzed.RESULTSTotal resection (total removal of cyst contents and capsule) was achieved in 8 patients (38.1%), near-total resection (total removal of cyst contents, incomplete removal of cyst capsule) in 9 patients (42.9%), and subtotal resection (incomplete removal of cyst contents and capsule) in 4 patients (19%). Larger cyst volume (≥ 3 cm3) and intradural location (15 cysts) were significantly associated with no...

Research paper thumbnail of Endoscopic Endonasal Surgery of the Skull Base: Training and Quality Assurance Model for Low-Volume Centers

Journal of Neurological Surgery Part B: Skull Base, 2017

Research paper thumbnail of Extended Endoscopic Endonasal Approach to the Anterior and Central Skull Base: Training and Quality Assurance Model for Low-Volume Centers

Journal of Neurological Surgery Part B: Skull Base, 2016

Research paper thumbnail of Development of a Skull Base Center in a Low-Volume Environment

Journal of Neurological Surgery Part B: Skull Base, 2016

Research paper thumbnail of Reconstruction of the cranial base after endonasal skull base surgery: Local tissue flaps

Operative Techniques in Otolaryngology-Head and Neck Surgery, 2010

Advances in endoscopic techniques and technology have substantially increased the scope of endona... more Advances in endoscopic techniques and technology have substantially increased the scope of endonasal skull base surgery. Large dural defects after expanded endonasal approaches (EEA) present a challenge for reconstruction and have revealed the limitations of conventional reconstructive methods. Initial reconstructive attempts using nonvascularized free tissue grafts resulted in unacceptably high rates of cerebrospinal fluid fistulae. The advent of vascularized, pedicled flaps has substantially improved these outcomes. These flaps also have the advantage of a large surface area and can be mobilized over a large arc of rotation. Vascularized tissue heals quickly and can tolerate postoperative radiation therapy. We have developed 3 nasal vascularized flaps that can be used for skull base reconstruction after EEA. The anatomy, technique, and reconstructive considerations for the nasoseptal flap, the inferior turbinate flap, and the middle turbinate flap will be reviewed in detail in the following report.

Research paper thumbnail of Endonasal surgery of the ventral skull base--endoscopic transcranial surgery

Oral and maxillofacial surgery clinics of North America, 2010

Skull base surgery is evolving from traditional transfacial and transcranial approaches to the en... more Skull base surgery is evolving from traditional transfacial and transcranial approaches to the endoscopic endonasal approach, a less intrusive corridor for accessing the ventral skull base. This technique eliminates facial scars, expedites recovery, and obviates brain retraction. The goals of surgical excision, whether palliative or curative, are identical: an approach that is less disruptive to normal tissues. By exploiting the sinonasal corridor, the entire ventral skull base may be accessed to successfully treat benign and malignant lesions. The expanding limits of endoscopic skull base surgery have been accompanied by commensurate innovations in reconstructive techniques that are reliable and have been shown to limit postoperative complications. This article describes the basis for this approach and provides the latest outcome data supporting the current state of the art for endoscopic skull base surgery.

Research paper thumbnail of Combined endoscopic endonasal transorbital approach with transconjunctival-medial orbitotomy for excisional biopsy of the optic nerve: technical note

Journal of neurological surgery reports, 2012

Background Access to the intraorbital optic nerve segment can be facilitated via a transcranial a... more Background Access to the intraorbital optic nerve segment can be facilitated via a transcranial approach that allows access to the entire orbital cavity. The endoscopic endonasal approach (EEA) combined with a transconjunctival-medial orbitotomy represents an alternative technique to achieve the same goal. Objective Report a surgical technique that allows total resection of the intraorbital optic nerve with minimal trauma and excellent results. Further extend and define the limits and indications of the EEA to orbital surgery. Methods A patient with rapidly progressive, but asymmetric, vision loss underwent EEA for optic nerve biopsy. Due to the undetermined histopathological diagnosis and complete unilateral vision loss, diagnostic total optic nerve resection was indicated. The entire intraorbital length of the nerve was resected via an endoscopic endonasal transorbital approach combined with transconjunctival-medial orbitotomy. Results A 2-cm intraorbital nerve segment was sent fo...

Research paper thumbnail of Endoscopic Endonasal Pituitary Surgery: Patient and Societal Costs of Surgical Education

Journal of Neurological Surgery Part B: Skull Base, 2012

Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of th... more Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of the anterior skull base. The minimally invasive access through an eyelid incision involves dissection in normal tissue planes, preserves frontalis muscle fi bers, avoids injury to the fronto-temporal facial nerve branches, and heals with excellent cosmetic results.

Research paper thumbnail of Endoscopic endonasal skull base surgery in the pediatric population

Journal of Neurosurgery-Pediatrics, 2013

S kull base lesions comprise a range of pathologies of neural, mesenchymal, notochordal, vascular... more S kull base lesions comprise a range of pathologies of neural, mesenchymal, notochordal, vascular, and, sometimes, epithelial origin. Such lesions are relatively rare in children and are mostly benign. 40 However, benign tumors can grow to exert mass effect and cause significant morbidity. 4 In many of these cases, excision is mandatory for their management. Additionally, skull base trauma may result in rhinorrhea requiring surgical repair. Pathology and trauma to the anterior cranial base have historically been approached via craniofacial resections. Although variations on this technique exist, most invariably involve a craniotomy, a transfacial approach, or a combined craniofacial approach. 26,41,60,61 Deep lesions may require brain retraction, heightening the risk of frontal lobe edema, infection, pneumocephalus, and other complications. 24,26 These approaches in children pose at Endoscopic endonasal skull base surgery in the pediatric population Clinical article

Research paper thumbnail of Endoscopic Endonasal Transpterygoid Nasopharyngectomy

Research paper thumbnail of Combined Surgical Approaches for Skull Base Chordomas

Journal of Neurological Surgery Part B: Skull Base, 2012

Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of th... more Conclusion: The transpalpebral "Eyelid" approach is an excellent option to approach lesions of the anterior skull base. The minimally invasive access through an eyelid incision involves dissection in normal tissue planes, preserves frontalis muscle fi bers, avoids injury to the fronto-temporal facial nerve branches, and heals with excellent cosmetic results.

Research paper thumbnail of A Novel Reconstructive Technique After Endoscopic Expanded Endonasal Approaches: Vascular Pedicle Nasoseptal Flap

The Laryngoscope, 2006

Background: In patients with large dural defects of the anterior and ventral skull base after end... more Background: In patients with large dural defects of the anterior and ventral skull base after endonasal skull base surgery, there is a significant risk of a postoperative cerebrospinal fluid leak after reconstruction. Reconstruction with vascularized tissue is desirable to facilitate rapid healing, especially in irradiated patients.Methods: We developed a neurovascular pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium based on the nasoseptal artery, a branch of the posterior septal artery (Hadad‐Bassagasteguy flap [HBF]). A retrospective review of patients undergoing endonasal skull base surgery at the University of Rosario, Argentina, and the University of Pittsburgh Medical Center was performed to identify patients who were reconstructed with a vascularized septal mucosal flap.Results: Forty‐three patients undergoing endonasal cranial base surgery were repaired with the septal mucosal flap. Two patients with postoperative cerebrospinal fluid leaks (5%) were su...

Research paper thumbnail of Endoscopic endonasal dissection of the infratemporal fossa: Anatomic relationships and importance of eustachian tube in the endoscopic skull base surgery

The Laryngoscope, 2010

Endoscopic endonasal approaches to the pterygopalatine and infratemporal fossae are technically c... more Endoscopic endonasal approaches to the pterygopalatine and infratemporal fossae are technically challenging due to the complex anatomy of these areas. This project attempts to develop an anatomic and surgical model to enhance the understanding of these spaces from the endonasal endoscopic perspective. Eight pterygopalatine and infratemporal fossae were dissected in four adult human specimens in accordance with institutional protocols. All specimens were prepared with vascular injections using colored latex. Both the pterygopalatine and infratemporal fossae were accessed using a transpterygoid approach, which included a medial maxillectomy. Rod lens endoscopes (with 0°, 30°, and 45° lenses), surgical microscope, microsurgical and endoscopic instruments were used to complete the dissections. Endoscopic endonasal approaches provided adequate access to the pterygopalatine and infratemporal fossae. Dissection of the internal maxillary artery and its terminal branches, and detachment of the medial and lateral pterygoid muscles were critical steps to access deeper structures of the infratemporal fossa. The lateral pterygoid plate was the most useful landmark to locate foramen ovale, and the mandibular branch of the trigeminal nerve. The Eustachian tube, medial pterygoid plate, and styloid process were the most useful landmarks to locate parapharyngeal poststyloid structures (parapharyngeal segment of the internal carotid artery, internal jugular vein, cranial nerves IX and X). A medial maxillectomy coupled with a transpterygoid endoscopic approach, provides adequate access to the pterygopalatine and infratemporal fossae. The complex anatomy of the infratemporal fossa requires precise identification of surgical landmarks to assure preservation of neurovascular structures.

Research paper thumbnail of Endoscopic Endonasal Approach for Nonvestibular Schwannomas

Neurosurgery, 2011

BACKGROUND Nonvestibular schwannomas of the skull base often represent a challenge owing to their... more BACKGROUND Nonvestibular schwannomas of the skull base often represent a challenge owing to their anatomic location. With improved techniques in endoscopic endonasal skull base surgery, resection of various ventral skull base tumors, including schwannomas, has become possible. OBJECTIVE To assess the outcomes of using endoscopic endonasal approach (EEA) for nonvestibular schwannomas of the skull base. METHODS Seventeen patients operated on for skull base schwannomas by EEA at the University of Pittsburgh Medical Center from 2003 to 2009 were reviewed. RESULTS Three patients underwent combined approaches with retromastoid craniectomy (n = 2) and orbitopterional craniotomy (n = 1). Three patients underwent multistage EEA. The rest received a single EEA operation. Data on degree of resection were found for 15 patients. Gross total resection (n = 9) and near-total…

Research paper thumbnail of Endoscopic Reconstruction of the Cranial Base Using a Pedicled Nasoseptal Flap

Operative Neurosurgery, 2008

Objective:Reconstruction of the cranial base using vascularized tissue promotes rapid and complet... more Objective:Reconstruction of the cranial base using vascularized tissue promotes rapid and complete healing, thus avoiding complications caused by persistent communication between the cranial cavity and the sinonasal tract. The Hadad-Bassagasteguy flap (HBF), a neurovascular pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium based on the nasoseptal artery, seems to be advantageous for the reconstruction of the cranial base after endonasal cranial base surgeryMethods:We performed a retrospective review of patients who underwent endonasal cranial base surgery at the University of Pittsburgh Medical Center from January 30, 2006 to January 30, 2007, identifying patients who experienced reconstruction with a vascularized septal mucosal flap (HBF). We analyzed the demographic data, pathological characteristics, site and extent of resection, use of cerebrospinal fluid (CSF) diversion techniques, and outcome.Results:Seventy-five patients who underwent endonasal cranial ba...

Research paper thumbnail of Endoscopic Endonasal Resection of Anterior Cranial Base Meningiomas

Neurosurgery, 2008

OBJECTIVE The endonasal route may be feasible for the resection of anterior cranial base tumors t... more OBJECTIVE The endonasal route may be feasible for the resection of anterior cranial base tumors that abut the paranasal sinuses. There are several case reports and mixed case series discussing this approach. Other than pituitary adenomas, there is a lack of literature describing the outcomes of endonasal approaches for single-tumor types such as meningiomas. METHODS In this study, we describe our current endoscopic endonasal technique and demonstrate the feasibility of using it to access anterior cranial base meningiomas from the back wall of the frontal sinus to the sella and laterally to the region of the midorbit. After this discussion, which includes key technical considerations and nuances, we address safety and efficacy by reporting the outcomes of our early experience with endoscopic endonasal resection of 35 anterior cranial base meningiomas. RESULTS A total of 35 patients underwent endoscopic endonasal resection of anterior cranial base meningiomas from October 2002 to Octo...