OBJECTIVE: The foundation of spine surgery centers on the proper identification, decompression, a... more OBJECTIVE: The foundation of spine surgery centers on the proper identification, decompression, and stabilization of bony and neural elements. We describe easily reproducible and reliable methods for optimal decompression and release of neural structures to alleviate symptoms and improve patients\u27 quality of life. METHODS: Multiple spinal decompression techniques were described in procedures for which the goal of surgery was decompression alone or decompression and fusion. Eight fundamental techniques were described: inverted U-cut, J-cut, T-cut, L-cut, Z-cut, I-track cuts, C-cut, and O-cut. RESULTS: These foundational cuts may be combined, as needed, to develop an individually tailored approach to the patient\u27s pathology. CONCLUSIONS: After properly identifying the anatomic structures, each of these techniques provides a consistent, reproducible, and efficient means to decompress the spine under various circumstances. These techniques provide surgical trainees with a framewor...
In this paper, the authors discuss the embryology and anatomy of the choroidal fissure, as well a... more In this paper, the authors discuss the embryology and anatomy of the choroidal fissure, as well as the pathophysiology and treatment of cerebrospinal fluid cysts of this structure. Understanding its anatomical relations to nearby structures plays an essential role during brain surgeries. With the advancement and availability of imaging techniques, lesions of the choroidal fissure are often found incidentally. Patients are usually asymptomatic or exhibit symptoms that do not correlate with anatomical location or do not require surgical treatment. The choroidal fissure is a key landmark used during brain surgery. Therefore, a comprehensive understanding of it and nearby anatomical structures is essential. Choroidal fissure cysts can be found incidentally, and well-known key features will allow one to differentiate them from other lesions. Surgical treatment should be reserved for symptomatic patients while asymptomatic patients should be monitored.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Vertebral osteomyelitis (VO) is a severe infection of the vertebral body and the adjacent disc sp... more Vertebral osteomyelitis (VO) is a severe infection of the vertebral body and the adjacent disc space, where Staphylococcus aureus is most commonly isolated. The objective of this retrospective study was to determine risk factors for and compare outcome differences between de novo methicillin-resistant Staphylococcus aureus (MRSA) VO and methicillin-sensitive Staphylococcus aureus (MSSA) VO. A retrospective cohort study was performed by review of the electronic medical records of 4541 consecutive spine surgery patients. Among these 37 underwent surgical treatment of de novo MRSA and MSSA spinal infections. Patient demographics, pre-and postoperative neurological status (ASIA impairment score), surgical treatment, inflammatory laboratory values, nutritional status, comorbidities, antibiotics, hospital stay, ICU stay, reoperation, readmission, and complications were collected. A minimum follow-up (FU) of 12 months was required. Among the 37 patients with de novo VO, 19 were MRSA and 18 were MSSA. Mean age was 52.4 and 52.9 years in the MRSA and MSSA groups, respectively. Neurological deficits were found in 53% of patients with MRSA infection and in 17% of the patients with MSSA infection, which was statistically significant (p < 0.05). Chronic renal insufficiency and malnutrition were found to be significant risk factors for MRSA VO. Preoperative albumin was significantly lower in the MRSA group (p < 0.05). Patients suffering from spinal infection with chronic renal insufficiency and malnutrition should be watched more carefully for MRSA. The MRSA group did not show a significant difference with regard to final clinical outcome despite more severe presentation.
Trabeculae or septations in the transverse sinus can have potentially life-threatening clinical s... more Trabeculae or septations in the transverse sinus can have potentially life-threatening clinical significance. The current study demonstrates trabecula/septum patterning within the transverse sinus with measurements and distribution data supplemented by imaging, and describes the possible etiology of idiopathic intracranial hypertension and turbulent blood flow in the transverse sinus. Twenty-four sides from 12 cadaveric heads, all fresh-frozen, were used (five males, seven females; age at death 65-91 years, mean 79.1 years). The length and diameter of the transverse sinus were measured along with the number and locations of septations/trabeculae and their tensile strength. The mean length of the transverse sinus was 68.43 mm on the right side and 74.31 mm on the left. A total of 42 septations were found in the 24 transverse sinuses. The number of septations per side ranged from zero to four with a mean of 1.75. The septations were located in the proximal 1/3 in 54.8% (23/42), the middle 1/3 in 21.4% (9/42), and the distal 1/3 in 23.8% (10/42). The work presented here furthers our understanding of transverse sinus anatomy, including its detailed internal architecture. The measurements can provide a technical guide for neurosurgeons and influence instrument selection when a large thrombus forms or anchors in one of these trabeculae or septa and necessitates treatment.
Herein we present a case of a horseshoe kidney with crossed fused renal ectopia. Both of these pa... more Herein we present a case of a horseshoe kidney with crossed fused renal ectopia. Both of these pathologies are congenital anomalies; however, to date, there are few cases that present with both. In this case, discovered during routine dissection, the fused kidney was mostly left-sided and very low in the pelvis. No renal artery arose from the right wall of the abdominal aorta, and the right renal vein drained into the lower part of the inferior vena cava (IVC) where the right and left common iliac veins joined. It is essential for clinicians and surgeons to understand these types of congenital anomalies, as they could impact patient care.
Most muscular structures in the human body are named based on their function, origin/insertion, o... more Most muscular structures in the human body are named based on their function, origin/insertion, or shape. During routine dissection of the back, an unusual muscle was found deep to the rhomboid muscles. The details of this case and a review of the extant literature are provided.
Study Design: In vitro biomechanical study. Objective: The transverse ligament is the strongest l... more Study Design: In vitro biomechanical study. Objective: The transverse ligament is the strongest ligament of the craniocervical junction and plays a critical role in atlanto-axial stability. The goal of this cadaveric study, and the subsequent study (part II), was to reevaluate the force required for the transverse ligament and alar ligament to fail in a more physiological biomechanical model in elderly specimens. Methods: Twelve C1-2 specimens were harvested from fresh-frozen Caucasian cadavers with a mean age at death of 81 years (range 68-89 years). Only the transverse ligament was preserved, and the bony C1-2 complex was left intact. The dens was pulled away from the anterior arch of C1 using a strength test machine that applies controlled increasing force. After testing, the axis was split in half to check for hidden pathologies and osteoporosis. The differences in the failure force between sex and age groups (group 1: <80 years, group 2: >80 years) were compared. Results:...
Journal of Neurological Surgery Part B: Skull Base, 2019
The anatomy and definition of the petroclinoid ligament (PCL) and its relationship with the abduc... more The anatomy and definition of the petroclinoid ligament (PCL) and its relationship with the abducens nerve are variably described. The goal of this study was to clarify the anatomy of the PCL and better elucidate its relationship with the abducens nerve. Thirty-six sides from 18 fresh-frozen adult cadaveric heads were used in this study. Specimens were all Caucasian and derived from 10 males and 8 females. The mean age at death was 79 years. Dissection of the PCL and abducens nerve was performed using a surgical microscope. The anterior and posterior attachments of the PCL, and position of the abducens nerve were noted. Subsequently, the width, thickness, and length of the ligament, and diameter of the abducens nerve were measured. Thirty-one sides (86.1%) were found to have a PCL, on two sides (5.6%), the PCL was ossified, and on three sides (8.3%), the PCL was absent. The width, thickness, and length of the PCL ranged from 0.54 to 3.39, 0.07 to 0.49, and 3.27 to 17.85 mm, respecti...
Introduction Encephalitis due to Cryptococcus neoformans has been seen almost exclusively in pati... more Introduction Encephalitis due to Cryptococcus neoformans has been seen almost exclusively in patients with severe compromise of their immune systems, such as acquired immune deficiency syndrome (AIDS). Fungal sinusitis with frank invasion through the cranial base and subsequent seeding of the central nervous system is rare, but should be considered in the differential of patients presenting with meningitis and sinus/skull base lesions even without obvious immune compromise. Improvements in diagnostic testing has increased the ability to correctly identify and new antimicrobials have allowed a condition that once carried a high morbidity and mortality to be managed with better outcomes. We present our treatment algorithm for successful management of an immunocompetent patient with extensive fungal encephalitis due to erosion through the skull base. Case Description The patient is a 59-year-old male presenting unresponsive with sphenoid mass erosive of the skull base and symptoms of m...
The great auricular nerve (GAN) has been used for trigeminal and facial nerve repair and the infe... more The great auricular nerve (GAN) has been used for trigeminal and facial nerve repair and the inferior alveolar nerve (IAN) are often sacrificed during segmental mandibulectomy. To our knowledge, only 1 case report has discussed IAN repair using GAN after segmental mandibulectomy. The goal of this study is to clarify the feasibility of using GAN for IAN repair. Eleven sides from 6 fresh frozen Caucasian cadavers were used for this study. The mean age at the time of death was 82.3 years. A submandibular skin incision was made 2 finger breadths below and parallel to the inferior border of the mandible. The GAN was identified and then the mental foramen was found via extraoral dissection. The buccal cortical bone was removed 5 mm posterior to the mental foramen to the wisdom tooth area. Next, the anteroposterior length of the window was measured. The diameter of the IAN at the first molar tooth area was measured. Finally, the GAN was cut with maximum available length to compare to the length of the window in the mandible. The anteroposterior length of the window and diameter of the IAN ranged from 23.1 to 31.2 mm and 1.2 to 2.1 mm, respectively. The length of the available GAN was longer than the ipsilateral bony window of the mandible on all sides. This study might encourage surgeons to consider a new way to treat patients who undergo segmental resection of the mandible with surgical neck dissection with injury to their IAN.
Ossification of parts of the intracranial dura mater is common and is generally accepted as an ag... more Ossification of parts of the intracranial dura mater is common and is generally accepted as an age-related finding. Additionally, duplication of the abducens nerve along its course to the lateral rectus muscle is a known, although uncommon anatomical variant. During routine cadaveric dissection, an ossified portion of dura mater traveling over the trigeminal nerve's entrance (porus trigeminus) into the middle cranial fossa was observed unilaterally. Ipsilaterally, a duplicated abducens nerve was also observed, with a unique foramen superolateral to the entrance of Dorello's canal. To our knowledge, there has been no existing report of a simultaneous ossified roof of the porus trigeminus with an ipsilateral duplicated abducens nerve. Herein, we discuss this case and the potential clinical and surgical applications. We believe this case report will be informative for the skull base surgeon in the diagnosis of neuralgic pain in the frontomaxillary, mandibular, orbital, and external and middle ear regions.
Posterior circulation strokes account for over one quarter of all ischemic strokes. The frequency... more Posterior circulation strokes account for over one quarter of all ischemic strokes. The frequency of vertebral artery origin stenosis (VAOS) in patients with vertebrobasilar insufficiency (VBI) has been estimated to be as high 26%e32%, and VAOS is the direct cause of posterior circulation strokes in 9% of patients. This association could have a significant genetic component. This study examines the feasibility of the internal thoracic artery (ITA) as a donor vessel for revascularization in patients with VAOS.-METHODS: Ten sides from 5 fresh-frozen white cadaveric necks derived from 3 women and 2 men were used in this study. The mean age of the cadavers at death was 77.2 years (range, 68e88 years). The subclavian artery, vertebral artery, and ITA were dissected. The length and diameter (proximal and distal) of the V1 segment and the length and diameter of the ITA were recorded. Finally, the ITA was transposed to the V1 segment of the vertebral artery (VA1).-RESULTS: The mean length of the VA1 and its diameter at the proximal and distal parts were 35.51 and 3.69 mm, respectively. The mean length and diameter of the ITA were 26.53 and 3.27 mm, respectively. Rerouting the ITA to the VA1 was feasible without tension on all sides.-CONCLUSIONS: This study indicates that the ITA is anatomically and hemodynamically an excellent option for bypass surgery in a VAOS scenario. We present convincing and reproducible data to aid neurosurgeons in choosing the procedure best suited to their patients.
The foundation of spine surgery centers on the proper identification, decompression, and stabiliz... more The foundation of spine surgery centers on the proper identification, decompression, and stabilization of bony and neural elements. We describe easily reproducible and reliable methods for optimal decompression and release of neural structures to alleviate symptoms and improve patients' quality of life.-METHODS: Multiple spinal decompression techniques were described in procedures for which the goal of surgery was decompression alone or decompression and fusion. Eight fundamental techniques were described: inverted Ucut, J-cut, T-cut, L-cut, Z-cut, I-track cuts, C-cut, and O-cut.-RESULTS: These foundational cuts may be combined, as needed, to develop an individually tailored approach to the patient's pathology.-CONCLUSIONS: After properly identifying the anatomic structures, each of these techniques provides a consistent, reproducible, and efficient means to decompress the spine under various circumstances. These techniques provide surgical trainees with a framework for approaching surgical decompression.
Study Design. Survey analysis among spine surgeons. Objective. To identify current consensus and ... more Study Design. Survey analysis among spine surgeons. Objective. To identify current consensus and discrepancies in managing adverse intraoperative events among spine surgeons. Summary of Background Data. Major intraoperative events are not commonly the subject of formal medical training, in part due to the relative paucity of their occurrence and in part due to an insufficient evidence base. Given the clinical impact of appropriate complication management, it is important to identify where surgeons may be able to improve decision making when choosing interventions. Methods. A survey was created including five hypothetical unpredicted scenarios affecting different organ systems to assess the respondents' preferred reactions. The five clinical vignettes that were selected by the researchers involved: 1) loss of spinal signals in neuro-monitoring, 2) prone position cardiac arrest, 3) prone position hypoxia during thoracic corpectomy and instrumentation, 4) supine cervical vertebral artery injury, and 5) sudden onset hypotension in major prone position reconstructive spine surgery. Twenty-eight surveys (Spine Fellows n ¼ 11; Spine surgeon Faculty n ¼ 17) were completed and returned to the investigators. Results were sorted and ranked according to the frequency each action was identified as a top five choice. Results. Following formal statistical evaluation loss of signals in neuro-monitoring had the statistically significantly most uniform response while the scenario involving cardiac compromise had the most heterogeneous. Many ''best'' responses had near or complete consensus while some ''distractor'' possibilities that could harm a patient were also selected by the respondents. Conclusion. The heterogeneity of responses in the face of ''disaster scenario'' intraoperative events shows there is room for more thorough and directed education of spine surgeons during training. As surgical teaching moves toward increased use of patient simulation and situational learning, these vignettes hopefully serve to provide direction for training future spine surgeons on how best to approach difficult situations.
Background Cervical transforaminal epidural steroid injections (CTFESIs) are sometimes performed ... more Background Cervical transforaminal epidural steroid injections (CTFESIs) are sometimes performed in patients with cervical radiculopathy secondary to nerve-root compression. Neck movements for patient positioning may include rotation, flexion, and extension. As physicians performing such procedures do not move the neck for fear of injuring the vertebral artery, we performed fluoroscopy and cadaveric dissection to analyze any movement of the vertebral artery during head movement and its relation to the foramina in the setting of CTFESI. Purpose To determine cervical rotational positioning for optimized vertebral artery location in the setting of cervical transforaminal epidural steroid injections. Material and Methods Four sides from two Caucasian whole cadavers (all fresh-frozen) were used. Using a guide wire and digital subtraction fluoroscopy, we evaluated the vertebral artery mimicking a CTFESI, then we removed the transverse processes and evaluated the vertebral artery by direct...
OBJECTIVE: The foundation of spine surgery centers on the proper identification, decompression, a... more OBJECTIVE: The foundation of spine surgery centers on the proper identification, decompression, and stabilization of bony and neural elements. We describe easily reproducible and reliable methods for optimal decompression and release of neural structures to alleviate symptoms and improve patients\u27 quality of life. METHODS: Multiple spinal decompression techniques were described in procedures for which the goal of surgery was decompression alone or decompression and fusion. Eight fundamental techniques were described: inverted U-cut, J-cut, T-cut, L-cut, Z-cut, I-track cuts, C-cut, and O-cut. RESULTS: These foundational cuts may be combined, as needed, to develop an individually tailored approach to the patient\u27s pathology. CONCLUSIONS: After properly identifying the anatomic structures, each of these techniques provides a consistent, reproducible, and efficient means to decompress the spine under various circumstances. These techniques provide surgical trainees with a framewor...
In this paper, the authors discuss the embryology and anatomy of the choroidal fissure, as well a... more In this paper, the authors discuss the embryology and anatomy of the choroidal fissure, as well as the pathophysiology and treatment of cerebrospinal fluid cysts of this structure. Understanding its anatomical relations to nearby structures plays an essential role during brain surgeries. With the advancement and availability of imaging techniques, lesions of the choroidal fissure are often found incidentally. Patients are usually asymptomatic or exhibit symptoms that do not correlate with anatomical location or do not require surgical treatment. The choroidal fissure is a key landmark used during brain surgery. Therefore, a comprehensive understanding of it and nearby anatomical structures is essential. Choroidal fissure cysts can be found incidentally, and well-known key features will allow one to differentiate them from other lesions. Surgical treatment should be reserved for symptomatic patients while asymptomatic patients should be monitored.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Vertebral osteomyelitis (VO) is a severe infection of the vertebral body and the adjacent disc sp... more Vertebral osteomyelitis (VO) is a severe infection of the vertebral body and the adjacent disc space, where Staphylococcus aureus is most commonly isolated. The objective of this retrospective study was to determine risk factors for and compare outcome differences between de novo methicillin-resistant Staphylococcus aureus (MRSA) VO and methicillin-sensitive Staphylococcus aureus (MSSA) VO. A retrospective cohort study was performed by review of the electronic medical records of 4541 consecutive spine surgery patients. Among these 37 underwent surgical treatment of de novo MRSA and MSSA spinal infections. Patient demographics, pre-and postoperative neurological status (ASIA impairment score), surgical treatment, inflammatory laboratory values, nutritional status, comorbidities, antibiotics, hospital stay, ICU stay, reoperation, readmission, and complications were collected. A minimum follow-up (FU) of 12 months was required. Among the 37 patients with de novo VO, 19 were MRSA and 18 were MSSA. Mean age was 52.4 and 52.9 years in the MRSA and MSSA groups, respectively. Neurological deficits were found in 53% of patients with MRSA infection and in 17% of the patients with MSSA infection, which was statistically significant (p < 0.05). Chronic renal insufficiency and malnutrition were found to be significant risk factors for MRSA VO. Preoperative albumin was significantly lower in the MRSA group (p < 0.05). Patients suffering from spinal infection with chronic renal insufficiency and malnutrition should be watched more carefully for MRSA. The MRSA group did not show a significant difference with regard to final clinical outcome despite more severe presentation.
Trabeculae or septations in the transverse sinus can have potentially life-threatening clinical s... more Trabeculae or septations in the transverse sinus can have potentially life-threatening clinical significance. The current study demonstrates trabecula/septum patterning within the transverse sinus with measurements and distribution data supplemented by imaging, and describes the possible etiology of idiopathic intracranial hypertension and turbulent blood flow in the transverse sinus. Twenty-four sides from 12 cadaveric heads, all fresh-frozen, were used (five males, seven females; age at death 65-91 years, mean 79.1 years). The length and diameter of the transverse sinus were measured along with the number and locations of septations/trabeculae and their tensile strength. The mean length of the transverse sinus was 68.43 mm on the right side and 74.31 mm on the left. A total of 42 septations were found in the 24 transverse sinuses. The number of septations per side ranged from zero to four with a mean of 1.75. The septations were located in the proximal 1/3 in 54.8% (23/42), the middle 1/3 in 21.4% (9/42), and the distal 1/3 in 23.8% (10/42). The work presented here furthers our understanding of transverse sinus anatomy, including its detailed internal architecture. The measurements can provide a technical guide for neurosurgeons and influence instrument selection when a large thrombus forms or anchors in one of these trabeculae or septa and necessitates treatment.
Herein we present a case of a horseshoe kidney with crossed fused renal ectopia. Both of these pa... more Herein we present a case of a horseshoe kidney with crossed fused renal ectopia. Both of these pathologies are congenital anomalies; however, to date, there are few cases that present with both. In this case, discovered during routine dissection, the fused kidney was mostly left-sided and very low in the pelvis. No renal artery arose from the right wall of the abdominal aorta, and the right renal vein drained into the lower part of the inferior vena cava (IVC) where the right and left common iliac veins joined. It is essential for clinicians and surgeons to understand these types of congenital anomalies, as they could impact patient care.
Most muscular structures in the human body are named based on their function, origin/insertion, o... more Most muscular structures in the human body are named based on their function, origin/insertion, or shape. During routine dissection of the back, an unusual muscle was found deep to the rhomboid muscles. The details of this case and a review of the extant literature are provided.
Study Design: In vitro biomechanical study. Objective: The transverse ligament is the strongest l... more Study Design: In vitro biomechanical study. Objective: The transverse ligament is the strongest ligament of the craniocervical junction and plays a critical role in atlanto-axial stability. The goal of this cadaveric study, and the subsequent study (part II), was to reevaluate the force required for the transverse ligament and alar ligament to fail in a more physiological biomechanical model in elderly specimens. Methods: Twelve C1-2 specimens were harvested from fresh-frozen Caucasian cadavers with a mean age at death of 81 years (range 68-89 years). Only the transverse ligament was preserved, and the bony C1-2 complex was left intact. The dens was pulled away from the anterior arch of C1 using a strength test machine that applies controlled increasing force. After testing, the axis was split in half to check for hidden pathologies and osteoporosis. The differences in the failure force between sex and age groups (group 1: <80 years, group 2: >80 years) were compared. Results:...
Journal of Neurological Surgery Part B: Skull Base, 2019
The anatomy and definition of the petroclinoid ligament (PCL) and its relationship with the abduc... more The anatomy and definition of the petroclinoid ligament (PCL) and its relationship with the abducens nerve are variably described. The goal of this study was to clarify the anatomy of the PCL and better elucidate its relationship with the abducens nerve. Thirty-six sides from 18 fresh-frozen adult cadaveric heads were used in this study. Specimens were all Caucasian and derived from 10 males and 8 females. The mean age at death was 79 years. Dissection of the PCL and abducens nerve was performed using a surgical microscope. The anterior and posterior attachments of the PCL, and position of the abducens nerve were noted. Subsequently, the width, thickness, and length of the ligament, and diameter of the abducens nerve were measured. Thirty-one sides (86.1%) were found to have a PCL, on two sides (5.6%), the PCL was ossified, and on three sides (8.3%), the PCL was absent. The width, thickness, and length of the PCL ranged from 0.54 to 3.39, 0.07 to 0.49, and 3.27 to 17.85 mm, respecti...
Introduction Encephalitis due to Cryptococcus neoformans has been seen almost exclusively in pati... more Introduction Encephalitis due to Cryptococcus neoformans has been seen almost exclusively in patients with severe compromise of their immune systems, such as acquired immune deficiency syndrome (AIDS). Fungal sinusitis with frank invasion through the cranial base and subsequent seeding of the central nervous system is rare, but should be considered in the differential of patients presenting with meningitis and sinus/skull base lesions even without obvious immune compromise. Improvements in diagnostic testing has increased the ability to correctly identify and new antimicrobials have allowed a condition that once carried a high morbidity and mortality to be managed with better outcomes. We present our treatment algorithm for successful management of an immunocompetent patient with extensive fungal encephalitis due to erosion through the skull base. Case Description The patient is a 59-year-old male presenting unresponsive with sphenoid mass erosive of the skull base and symptoms of m...
The great auricular nerve (GAN) has been used for trigeminal and facial nerve repair and the infe... more The great auricular nerve (GAN) has been used for trigeminal and facial nerve repair and the inferior alveolar nerve (IAN) are often sacrificed during segmental mandibulectomy. To our knowledge, only 1 case report has discussed IAN repair using GAN after segmental mandibulectomy. The goal of this study is to clarify the feasibility of using GAN for IAN repair. Eleven sides from 6 fresh frozen Caucasian cadavers were used for this study. The mean age at the time of death was 82.3 years. A submandibular skin incision was made 2 finger breadths below and parallel to the inferior border of the mandible. The GAN was identified and then the mental foramen was found via extraoral dissection. The buccal cortical bone was removed 5 mm posterior to the mental foramen to the wisdom tooth area. Next, the anteroposterior length of the window was measured. The diameter of the IAN at the first molar tooth area was measured. Finally, the GAN was cut with maximum available length to compare to the length of the window in the mandible. The anteroposterior length of the window and diameter of the IAN ranged from 23.1 to 31.2 mm and 1.2 to 2.1 mm, respectively. The length of the available GAN was longer than the ipsilateral bony window of the mandible on all sides. This study might encourage surgeons to consider a new way to treat patients who undergo segmental resection of the mandible with surgical neck dissection with injury to their IAN.
Ossification of parts of the intracranial dura mater is common and is generally accepted as an ag... more Ossification of parts of the intracranial dura mater is common and is generally accepted as an age-related finding. Additionally, duplication of the abducens nerve along its course to the lateral rectus muscle is a known, although uncommon anatomical variant. During routine cadaveric dissection, an ossified portion of dura mater traveling over the trigeminal nerve's entrance (porus trigeminus) into the middle cranial fossa was observed unilaterally. Ipsilaterally, a duplicated abducens nerve was also observed, with a unique foramen superolateral to the entrance of Dorello's canal. To our knowledge, there has been no existing report of a simultaneous ossified roof of the porus trigeminus with an ipsilateral duplicated abducens nerve. Herein, we discuss this case and the potential clinical and surgical applications. We believe this case report will be informative for the skull base surgeon in the diagnosis of neuralgic pain in the frontomaxillary, mandibular, orbital, and external and middle ear regions.
Posterior circulation strokes account for over one quarter of all ischemic strokes. The frequency... more Posterior circulation strokes account for over one quarter of all ischemic strokes. The frequency of vertebral artery origin stenosis (VAOS) in patients with vertebrobasilar insufficiency (VBI) has been estimated to be as high 26%e32%, and VAOS is the direct cause of posterior circulation strokes in 9% of patients. This association could have a significant genetic component. This study examines the feasibility of the internal thoracic artery (ITA) as a donor vessel for revascularization in patients with VAOS.-METHODS: Ten sides from 5 fresh-frozen white cadaveric necks derived from 3 women and 2 men were used in this study. The mean age of the cadavers at death was 77.2 years (range, 68e88 years). The subclavian artery, vertebral artery, and ITA were dissected. The length and diameter (proximal and distal) of the V1 segment and the length and diameter of the ITA were recorded. Finally, the ITA was transposed to the V1 segment of the vertebral artery (VA1).-RESULTS: The mean length of the VA1 and its diameter at the proximal and distal parts were 35.51 and 3.69 mm, respectively. The mean length and diameter of the ITA were 26.53 and 3.27 mm, respectively. Rerouting the ITA to the VA1 was feasible without tension on all sides.-CONCLUSIONS: This study indicates that the ITA is anatomically and hemodynamically an excellent option for bypass surgery in a VAOS scenario. We present convincing and reproducible data to aid neurosurgeons in choosing the procedure best suited to their patients.
The foundation of spine surgery centers on the proper identification, decompression, and stabiliz... more The foundation of spine surgery centers on the proper identification, decompression, and stabilization of bony and neural elements. We describe easily reproducible and reliable methods for optimal decompression and release of neural structures to alleviate symptoms and improve patients' quality of life.-METHODS: Multiple spinal decompression techniques were described in procedures for which the goal of surgery was decompression alone or decompression and fusion. Eight fundamental techniques were described: inverted Ucut, J-cut, T-cut, L-cut, Z-cut, I-track cuts, C-cut, and O-cut.-RESULTS: These foundational cuts may be combined, as needed, to develop an individually tailored approach to the patient's pathology.-CONCLUSIONS: After properly identifying the anatomic structures, each of these techniques provides a consistent, reproducible, and efficient means to decompress the spine under various circumstances. These techniques provide surgical trainees with a framework for approaching surgical decompression.
Study Design. Survey analysis among spine surgeons. Objective. To identify current consensus and ... more Study Design. Survey analysis among spine surgeons. Objective. To identify current consensus and discrepancies in managing adverse intraoperative events among spine surgeons. Summary of Background Data. Major intraoperative events are not commonly the subject of formal medical training, in part due to the relative paucity of their occurrence and in part due to an insufficient evidence base. Given the clinical impact of appropriate complication management, it is important to identify where surgeons may be able to improve decision making when choosing interventions. Methods. A survey was created including five hypothetical unpredicted scenarios affecting different organ systems to assess the respondents' preferred reactions. The five clinical vignettes that were selected by the researchers involved: 1) loss of spinal signals in neuro-monitoring, 2) prone position cardiac arrest, 3) prone position hypoxia during thoracic corpectomy and instrumentation, 4) supine cervical vertebral artery injury, and 5) sudden onset hypotension in major prone position reconstructive spine surgery. Twenty-eight surveys (Spine Fellows n ¼ 11; Spine surgeon Faculty n ¼ 17) were completed and returned to the investigators. Results were sorted and ranked according to the frequency each action was identified as a top five choice. Results. Following formal statistical evaluation loss of signals in neuro-monitoring had the statistically significantly most uniform response while the scenario involving cardiac compromise had the most heterogeneous. Many ''best'' responses had near or complete consensus while some ''distractor'' possibilities that could harm a patient were also selected by the respondents. Conclusion. The heterogeneity of responses in the face of ''disaster scenario'' intraoperative events shows there is room for more thorough and directed education of spine surgeons during training. As surgical teaching moves toward increased use of patient simulation and situational learning, these vignettes hopefully serve to provide direction for training future spine surgeons on how best to approach difficult situations.
Background Cervical transforaminal epidural steroid injections (CTFESIs) are sometimes performed ... more Background Cervical transforaminal epidural steroid injections (CTFESIs) are sometimes performed in patients with cervical radiculopathy secondary to nerve-root compression. Neck movements for patient positioning may include rotation, flexion, and extension. As physicians performing such procedures do not move the neck for fear of injuring the vertebral artery, we performed fluoroscopy and cadaveric dissection to analyze any movement of the vertebral artery during head movement and its relation to the foramina in the setting of CTFESI. Purpose To determine cervical rotational positioning for optimized vertebral artery location in the setting of cervical transforaminal epidural steroid injections. Material and Methods Four sides from two Caucasian whole cadavers (all fresh-frozen) were used. Using a guide wire and digital subtraction fluoroscopy, we evaluated the vertebral artery mimicking a CTFESI, then we removed the transverse processes and evaluated the vertebral artery by direct...
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Papers by Juan Altafulla