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Background: Many are familiar with the parotid duct and the Danish physician/anatomist's name associated with it. However, most are unaware of Niels Stensen's life and his significant contributions to the early study of the heart. For example, he found that the heart is simply muscle and was the first to describe what we now refer to as the tetralogy of Fallot., Methods: A review of germane literature regarding this pioneer of cardiac anatomy was performed., Conclusions: This physician of the Medici court was clearly ahead of his time and found errors in the publications of such giants as Varolius and Willis. The tetralogy of Fallot should rightfully, be termed the tetralogy of Stensen. The present review discusses the life of this 17th century anatomist, physician and priest/bishop and highlights his contributions to cardiac anatomy and pathology., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Sir John Struthers, Scottish anatomist, professor, and surgeon, was an early advocate of clinical training in medical education, and his impact is still visible today. He was one of the first prominent anatomists in the United Kingdom to endorse Charles Darwin's controversial theory of natural selection, and his research reflected a desire to illustrate these ideas in cadaveric specimens. Struthers is remembered eponymously for 2 connective tissue condensations in the arm, an arcade and ligament, which may entrap the ulnar and median nerves, respectively. He studied medicine at the University of Edinburgh, received a Doctor of Laws degree from the University of Glasgow, served on the General Medical Council from 1883 to 1891, was president of the Royal College of Surgeons from 1895 to 1897, and was knighted by Queen Victoria in 1898. Struthers' devotion to medical education and insistence on the importance of clinical training laid the foundation for current medical curricula around the world. His observations of sites of potential nerve entrapment in the arm are still taught to neurosurgical trainees today.

In contrast to many other physicians of his age, John Browne (1642-1702), an English anatomist and surgeon, managed to strike a balance in his career that spanned relative obscurity, prestige, and notoriety. Among his more prestigious credits, Browne was Surgeon in Ordinary to King Charles II and William III. He also had numerous publications to his name, some of which are credited as great innovations. His career, however, was tempered by his most important book, which has been critiqued by his contemporaries as well as modern historians as plagiarism. Although Browne undeniably copied the works of others and published them under his name, he was not alone in this practice. Various forms of intellectual thievery were common in Browne's day, and there were many perpetrators. The life of this overlooked figure in the history of anatomy and the stigma attached to him will be examined.

This article, published in the Journal of Neurological Surgery, explores the microsurgical anatomy of the "true" petrous apex and the feasibility of accessing it through the endoscopic endonasal approach. The study conducted detailed dissections of post-mortem human specimens and identified key anatomical landmarks and neurovascular structures. The authors found that the endoscopic endonasal petrosectomy approach provides access to the "true" petrous apex, with two variants based on its relationship with the internal carotid artery. The study concludes that this approach is an effective surgical alternative for accessing lesions in this region. [Extracted from the article]

Background Surgical treatment of ventral and ventrolateral lesions of the craniocervical junction are among the most challenging neurosurgical pathologies to treat. Three surgical techniques, the far lateral approach (and its variations), the anterolateral approach, and the endoscopic far medial approach can be used to approach and resect lesions in this area. Objective The aim of the study is to examine the surgical anatomy of three skull base approaches to the craniocervical junction and review surgical cases to better understand the indications and possible complications for each of these approaches. Methods Cadaveric dissections with standard microsurgical and endoscopic instruments were performed for each of the three surgical approaches, and key steps and surgically relevant anatomy were documented. Six patients with appropriate pre-, post-, and intraoperative imaging and video documentation are presented and discussed accordingly. Results Based on our institutional experience, all three approaches can be utilized to safely and effectively approach a wide variety of neoplastic and vascular pathology. Unique anatomical characteristics, lesion morphology and size, and tumor biology should all be considered when determining the optimal approach. Conclusion Preoperative assessment of surgical corridors with 3D illustrations helps to define the best surgical corridor. 360 degree knowledge of the anatomy of craniovertebral junction allows safe surgical approach and treatment of ventral and ventrolateral located lesions using one of the three approaches. [ABSTRACT FROM AUTHOR]

Background: Accessing the hippocampus for amygdalohippocampectomy and minimally invasive procedures, such as depth electrode placement, require an accurate knowledge regarding the location of the hippocampus. Methods: The authors removed 10 human cadaveric brains from the cranium and observed the relationships between the lateral temporal neocortex and the underlying hippocampus. They then measured the distance between the hippocampus and superficial landmarks. The authors also validated their study using magnetic resonance imaging (MRI) scans of 10 patients suffering from medial temporal lobe sclerosis where the distance from the hippocampal head to the anterior temporal tip was measured. Results: In general, the length of the hippocampus was along the inferior temporal sulcus and inferior aspect of the middle temporal gyrus. Although the hippocampus tended to be more superiorly located in female specimens and on the left side, this did not reach statistical significance. The length of the hippocampus tended to be shorter in females, but this too failed to reach statistical significance. The mean distance from the anterior temporal tip to the hippocampal head was identical in the cadavers and MRIs of patients with medial temporal lobe sclerosis. Conclusions: Additional landmarks for localizing the underlying hippocampus may be helpful in temporal lobe surgery. Based on this study, there are relatively constant anatomical landmarks between the hippocampus and overlying temporal cortex. Such landmarks may be used in localizing the hippocampus during amygdalohippocampectomy and depth electrode implantation in verifying the accuracy of image-guided methods and as adjuvant methodologies when these latter technologies are not used or are unavailable. [ABSTRACT FROM AUTHOR]

Chronic postoperative neuralgias and headache following retrosigmoid craniotomy can be uncomfortable for the patient. We aimed to better elucidate the regional nerve anatomy in an effort to minimize this postoperative complication. Ten adult cadaveric heads (20 sides) were dissected to observe the relationship between the lesser occipital nerve and a traditional linear versus modified U incision during retrosigmoid craniotomy. Additionally, the relationship between these incisions and the occipital artery were observed. The lesser occipital nerve was found to have two types of course. Type I nerves (60%) remained close to the posterior border of the sternocleidomastoid muscle and some crossed anteriorly over the sternocleidomastoid muscle near the mastoid process. Type II nerves (40%) left the posterior border of the sternocleidomastoid muscle and swung medially (up to 4.5 cm posterior to the posterior border of the sternocleidomastoid muscle) as they ascended over the occiput. The lesser occipital nerve was near a midpoint of a line between the external occipital protuberance and mastoid process in all specimens with the type II nerve configuration. Based on our findings, the inverted U incision would be less likely to injure the type II nerves but would necessarily cross over type I nerves, especially more cranially on the nerve at the apex of the incision. As the more traditional linear incision would most likely transect the type I nerves and more so near their trunk, the U incision may be the overall better choice in avoiding neural and occipital artery injury during retrosigmoid approaches. [ABSTRACT FROM AUTHOR]

Desorption electrospray ionization—mass spectrometry (DESI-MS) imaging was used to analyze unmodified human brain tissue sections from 39 subjects sequentially in the positive and negative ionization modes. Acquisition of both MS polarities allowed more complete analysis of the human brain tumor lipidome as some phospholipids ionize preferentially in the positive and others in the negative ion mode. Normal brain parenchyma, comprised of grey matter and white matter, was differentiated from glioma using positive and negative ion mode DESI-MS lipid profiles with the aid of principal component analysis along with linear discriminant analysis. Principal component–linear discriminant analyses of the positive mode lipid profiles was able to distinguish grey matter, white matter, and glioma with an average sensitivity of 93.2% and specificity of 96.6%, while the negative mode lipid profiles had an average sensitivity of 94.1% and specificity of 97.4%. The positive and negative mode lipid profiles provided complementary information. Principal component–linear discriminant analysis of the combined positive and negative mode lipid profiles, via data fusion, resulted in approximately the same average sensitivity (94.7%) and specificity (97.6%) of the positive and negative modes when used individually. However, they complemented each other by improving the sensitivity and specificity of all classes (grey matter, white matter, and glioma) beyond 90% when used in combination. Further principal component analysis using the fused data resulted in the subgrouping of glioma into two groups associated with grey and white matter, respectively, a separation not apparent in the principal component analysis scores plots of the separate positive and negative mode data. The interrelationship of tumor cell percentage and the lipid profiles is discussed, and how such a measure could be used to measure residual tumor at surgical margins. [ABSTRACT FROM AUTHOR]

Relatively few studies have been performed that analyze the morphology of the choroid plexus of the fourth ventricle. Due to the importance of this tissue as a landmark on imaging and during surgical intervention of the fourth ventricle, the authors performed a cadaveric study to better characterize this important structure. The choroid plexus of the fourth ventricle of 60 formalin fixed adult human brains was examined and measured. The horizontal distance from the midline to the lateral most point of the protruding tip of the horizontal limbs was measured. In the majority of the 60 brain specimens, right and left horizontal limbs of the choroid plexus were seen extending from the midline and protruding out of their respective lateral apertures of the fourth ventricle and into the subarachnoid space. However, on 3.3% of sides, there was absence of an extension into the foramen of Luschka and in one specimen, this lack of extension into the foramen of Luschka was bilateral. On two sides, there was discontinuity between the midline choroid plexus and the tuft of choroid just outside the foramen of Luschka. For specimens in which the choroid plexus did protrude through the foramen of Luschka (96.7%), these tufts were located anterior to the flocculus and inferolateral to the facial/vestibulocochlear nerve complex and posterosuperior to the glossopharyngeal/vagal/accessory complex. A thorough understanding of the normal and variant anatomy of the fourth ventricular choroid plexus is necessary for those who operate in, or interpret imaging of, this region. [ABSTRACT FROM AUTHOR]

Introduction Preserving cranial nerve (CN) function during tumor removal at the jugular foramen is challenging. No anatomical study has better defined the relevant dural septations on the inner surface of the jugular foramen. This study was undertaken to elucidate this anatomy. Methods Fourteen cadaveric heads (28 sides) were dissected, and relationships of the meningeal coverings of the jugular foramen and adjacent CNs documented. A classification scheme was created to better describe the dural septations of the inner surface of the jugular foramen. Results Four types of dural septations were noted. Type I: 10 sides (36%) where a dural septation was seen between CNs IX anteriorly and X and XI posteriorly. Of these, the septum was ossified in 20%. Type II (32%) was defined as a jugular foramen with no dural septation. Type III (7%) was defined as septation between CNs IX and X anteriorly and XI posteriorly. Type IV (7 sides, 25%) or the chaotic form was defined asmultiple septations within the jugular foramen that housed and divided CN rootlets. Conclusions The dural septations defined here can be used in future studies to help correlate operative strategy to meningeal morphology within the jugular foramen. [ABSTRACT FROM AUTHOR]

Background: The location of the temporal horn is important to neurosurgeons during procedures such as amygdalohippocampectomy and intraventricular electrode placement for temporal lobe seizure monitoring. However, sometimes the temporal horn is difficult to localize, especially without neuronavigation. The authors aimed to better localize this structure using superficial anatomic landmarks. Methods: Twenty-two brain halves were dissected from the midline, and the fornix identified and followed toward the left and right temporal horns. Once the temporal horn was isolated from a mesial approach, 6-cm long needles were placed into its anterior and posterior walls of the temporal horn and passed laterally from the axial plane to the cortical surface. Pin exit sites were marked externally and measurements taken between the outer temporal lobe cortex and the underlying temporal horn. Results: No statistical differences were noted between left and right sides. The temporal horn was generally directed anteroinferiorly and best marked externally by the inferior temporal sulcus. The mean length of the temporal horn was 4.4 cm. Mean distance from anterior temporal tip to anterior wall of the temporal horn was 3.3 cm. The mean distance from the anterior temporal tip to the posterior wall of the temporal horn was 7 cm. The anterior wall of the temporal horn was a mean of 3 mm superior to the inferior temporal sulcus. The posterior wall was a mean of 1.2 cm superior to the inferior temporal sulcus. Conclusions: These landmarks and measurements may help neurosurgeons better localize this part of the lateral ventricular system. [ABSTRACT FROM AUTHOR]

Background: Accessing the hippocampus for amygdalohippocampectomy and procedures such as depth electrode placement requires accurate knowledge regarding the location of the hippocampus. Methods: The authors removed 10 human cadaveric brains (20 sides) from their crania, noted relationships between the lateral temporal neocortex and underlying hippocampus, and measured the distance between the hippocampus and superficial landmarks. Results: Mean distances were as follows: 3.8 cm from the tip of the temporal lobe to the head of the hippocampus; 6.5 cm from the tip of the temporal lobe to the junction of the fornix and hippocampus; and 3.5 cm between the tail and head of the hippocampus. The head of the hippocampus ranged from 0 to 5 mm inferior to the inferior temporal sulcus. The tail of the hippocampus ranged from 2.2 to 7 mm superior to the inferior temporal sulcus. In two specimens, the tail was deep to the superior temporal sulcus. Generally the length of the hippocampus was along the inferior temporal sulcus and inferior aspect of the middle temporal gyrus. The hippocampus tended to be more superiorly located and shorter in females and left sides, but this was not statistically significant. Conclusions: Additional landmarks for localizing the underlying hippocampus may be helpful in temporal lobe surgery. Our study showed relatively constant anatomic landmarks between the hippocampus and overlying temporal cortex that may help localize the hippocampus during amygdalohippocampectomy and depth electrode implantation, verify the accuracy of image-guided methods, and used as adjuvant methodologies when these latter technologies are unavailable. [ABSTRACT FROM AUTHOR]

Introduction. Most sources conclude that the spinal accessory nerve (SAN) is a purely motor nerve. There are some reports that suggest a sensory component, although the exact nature of such sensory fibers has yet to be elucidated. With such discrepancies in the literature and with well-established pain syndromes of unknown etiology following SAN injury, the authors performed the present study to better clarify this anatomy. Materials and methods. The entire accessory nerve was harvested from 10 adult cadavers. Samples were then submitted for immunohistochemical analyses. Results. Occasional microganglia cells were identified along the SAN in all specimens. These ganglia were most numerous along the intracranial segment of the SAN, but none was found along the cranial rootlets of the accessory nerve. Conclusions. Neuronal cell bodies were identified along the course of the SAN in human cadavers. Although the function is not certain, such cells have been found in other animals to be nocioceptive in nature. Pending further study, these cells may be found to be involved in enigmatic pain syndromes thought to arise in the sternocleidomastoid and trapezius muscles. [ABSTRACT FROM AUTHOR]

Background. One variant branch of the P1 segment of the posterior cerebral artery (PCA) is the artery of Percheron (AOP). This unilateral trunk supplies thalami and potentially mesencephalic structures. As studies of this vessel are scant in the literature and damage to this artery can have catastrophic results, the authors performed this study to better elucidate its morphology. Materials and methods. Twenty-five adult latex-injected cadaveric heads underwent brain removal and microdissection with specific attention to the presence of the AOP. When identified, measurements were made and observations given to the origin and course of this vessel. A case illustration is also presented that demonstrates bilateral thalamic and midbrain infarctions most likely due to thrombosis of the AOP. Results. An AOP was identified in three specimens (12%)-2 right and 1 left side (1 male and 2 female specimens) and arose, on average, 8 mm lateral to the basilar artery bifurcation. The average diameter was 2.1 mm, and the length between the origin and brain penetration had a mean distance of 1.5 cm. In all specimens, the AOP had a coiled appearance, especially in its proximal extraparenchymal segment. The contralateral P1 segment of the PCA was not absent or hypoplastic in any of the three specimens. All arteries supplied small branches to the ipsilateral and contralateral thalami and midbrain. Conclusions. Knowledge of the AOP may be important during surgical or neuroendovascular approaches to the basilar bifurcation or during interpretation of imaging, especially in patients presenting with bilateral thalamic and midbrain infarctions. [ABSTRACT FROM AUTHOR]

Introduction. Few reports have mentioned the artery of Davidoff and Schechter (ADS). Therefore, this variant tentorial branch of the posterior cerebral artery (PCA) was studied. Materials and methods. Twenty adult latex-injected cadaveric heads (40 sides) underwent microdissection with specific attention given to the presence of the ADS. When identified, measurements and observations were made of the source and course of this vessel. Two case illustrations were also provided for clinical application. Results. An ADS was identified on 10 sides (25%). This artery was found to always be a branch of the P2 segment of the PCA and typically traveled posterolateral under the superior cerebellar artery and superior to the trochlear nerve to enter the deep surface of the tentorium cerebelli roughly near the midpoint of the ipsilateral one-half of the incisura. From this point, the vessel traveled posterior to approximately the midline where it took an upward course to supply the falcotentorial junction. The average diameter of the vessel was 0.8 mm with a mean length of 1.2 cm. The artery was found to be more common in male specimens and on left sides (p < 0.05). Bilateral occurrence was seen in one male specimen. Conclusions. Knowledge of the ADS may be important during approaches to the ambient cistern or in interpretation of imaging such as its involvement in tentorial arteriovenous malformations. [ABSTRACT FROM AUTHOR]

Background and Study Aims Little information can be found in the literature regarding the relationships of the posterior interosseous nerve (PIN) while it traverses the supinator muscle. Because compression syndromes may involve this nerve at this site and researchers have investigated using branches of the PIN to the supinator for neurotization procedures, the authors' aim was to elucidate information about this anatomy. Materials and Methods Dissection was performed on 52 cadaveric limbs to investigate branching patterns of the PIN within the supinator muscle. Results On 29 sides, the PIN entered the supinator muscle as a single nerve and from its medial side provided two to four branches to the muscle. On 23 sides, the nerve entered the supinatormuscle as two approximately equal-size branches that arose from the radial nerve on average 2.2 cmfromthe proximal edge of thismuscle. In these cases, the medial of the two branches terminated on the supinator muscle, and the lateral branch traveled through the supinator muscle; in 13 specimens, it provided additional smaller branches to the supinatormuscle. The length of PIN within the supinator muscle was 4 cm on average, and the diameter of its branches to the supinator muscle ranged from 0.8 to 1.1 mm. In 10 specimens, the PIN left the supinator muscle before the most distal aspect of the muscle. In two specimens with a single broad PIN, muscle fibers of the supinator muscle pierced the PIN as it traveled through it. Conclusion This knowledge of the anatomy of the PIN as it passes through the supinator muscle may be useful to neurosurgeons during decompressive procedures or neurotization. [ABSTRACT FROM AUTHOR]

Introduction: The human skull is a complex structure that deserves continued study. Few studies have directed their attention to the development, pathology, and molecular formation of the human calvaria. Materials and methods: A review of the medical literature using standard search engines was performed to locate studies regarding the human calvaria. Results: The formation of the human calvaria is a complex interaction between bony and meningeal elements. Derailment of these interactions may result in deformation of this part of the skull. Conclusions: Knowledge of the anatomy, formation, and pathology of the human calvaria will be of use to the clinician that treats skull diseases. With an increased understanding of genetic and molecular biology, treatment paradigms for calvarial issues may change. [ABSTRACT FROM AUTHOR]

The adductor minimus muscle has had scant and conflicting reports regarding its anatomy with some authors ignoring its existence altogether. The present study was conducted to more precisely describe the anatomy of this muscle. Forty human cadavers underwent dissection of the posterior thigh for observation of the adductor minimus muscle. When identified, this muscle was measured and relationships to the muscle documented. Additionally, five fetuses were dissected to observe for the presence of the adductor minimus muscle. The adductor minimus muscle was found in roughly one half of our specimens and was seen in all fetal specimens. When absent, the quadratus femoris muscle was always more prominent and extended more inferiorly toward the territory of the adductor minimus muscle. The average maximal length, width and thickness for the adductor minimus muscle was 14.6 cm, 7 cm, and 2.25 mm, respectively. Such data may be of consequence to clinicians who rehabilitate posterior thigh musculature or surgeons who operate this region. [ABSTRACT FROM AUTHOR]

Background: Significant controversy exists regarding the existence of the so-called arcade of Struthers and whether this structure is involved in some cases of proximal ulnar nerve entrapment. Therefore, the aim of the present study was to further elucidate this anatomy. Methods: Fifteen cadavers (30 sides) underwent dissection of the medial arm with special attention to the course of the ulnar nerve and its relationships to the soft tissues of this region. Results: We identified a thickening in the inferior medial arm that crosses the ulnar nerve and is consistent with the so-called arcade of Struthers in 86.7% of sides. On 57.7% of the sides, the arcade was found to be due to a thickening of the brachial fascia and was classified as a type I arcade. On 19.2% of the sides, the arcade was due to the internal brachial ligament and these were classified as type II arcades. On 23.1% of the sides, the arcade was due to a thickened medial intermuscular septum and these were classified as type III arcades. The mean length of the arcade was 4.3 cm and the distal end of the arcade was, on average, 6.8 cm above the medial epicondyle. Although the presence of an arcade of Struthers was slightly more common in female specimens, this did not reach statistical significance. However, arcades were found more often on right side (P < 0.001). Conclusions: Based on our findings, the arcade of Struthers is an anatomical band of connective tissue in the medial distal arm that crosses the ulnar nerve. This structure was found in the majority of our specimens and may need to be evaluated in proximal ulnar neuropathies. We believe that past studies that have not observed the arcade and past studies with varied findings are due to the various definitions used for this anatomical structure. Using the classification system as demonstrated in the present study may make future communications regarding the arcade of Struthers more exact. [ABSTRACT FROM AUTHOR]

Background: Neurosurgical intervention involving the scalp may cause neuralgia or other pain syndromes. Therefore, a comprehensive understanding of scalp innervation may be helpful in prevention of pain potentially induced by surgery. Methods: Using standard search engines, a review of the literature regarding the anatomy of the nerves that innervate the scalp was performed with attention given to anatomic landmarks. Results: This paper provides a comprehensive review of the anatomy, embryology, pathology, and neurosurgical application of the knowledge of the innervation of the scalp. Conclusions: Knowledge of the nerves that supply the scalp is important to the neurosurgeon who hopes to maximize patient recovery and minimize postprocedural complications. [ABSTRACT FROM AUTHOR]

We hypothesized that a correlation may exist between the length of the upper limb and the length of the cubital tunnel, which transmits the ulnar nerve from the arm to the forearm. If true, this association might aid in predicting individuals at greater risk of developing ulnar nerve compression at this site. A total of 46 cadaveric upper limbs were dissected. The lengths of the upper limb and cubital tunnel were measured and analysis made of any correlation between these two distances. The average length of the cubital tunnel was found to be 2.7 cm (range 1.2–4.7 cm, SD 0.82), and the average length of the upper limb was 62.5 cm (range 51–72 cm, SD 4.33). No significant difference was found with either length of the tunnel between left and right sides or among genders. Neither the ratio of upper limb length to length of the cubital tunnel between genders nor the ratio between left and right sides was found to have a positive correlation. These data suggest that the cubital tunnel length maintains similar proportion to upper limb length among genders and sides and that a correlation between these two distances does not exist. [ABSTRACT FROM AUTHOR]

Introduction. Medically recalcitrant spasmodic torticollis may necessitate surgical intervention. One procedure used for this pathologic entity is intradural rhizotomy. However, some patients are symptomatic, perhaps due to an overlooked or underappreciated nerve of McKenzie. The authors' goal was to further elucidate the anatomy of this nerve of the craniocervical junction. Materials and methods. Fifteen adult cadavers (30 sides) underwent microsurgical dissection and observations of the nerve of McKenzie. Morphometrics were performed and anatomic relationships were documented under surgical magnification. Results. The nerve of McKenzie was found on 70% of sides and was always a single branch. Average length was 5.2 mm for left sides and 6 mm for right sides. Average diameter was 0.9 mm (0.5-1.2 mm). In two specimens, the nerve was found bilaterally. It pierced the first denticulate ligament on 11 sides (52.4%) and travelled through its two prongs on three sides (14.3%) to connect to the anteriorly placed C1 ventral root. On five sides, it was in intimate contact with the adventitia of the vertebral artery. It was more common on right sides and in males, and this was statistically significant. Conclusions. The authors identified the nerve of McKenzie in most specimens. This nerve, if overlooked during surgical treatment of spasmodic torticollis, may result in continued symptoms. The nerve of McKenzie was often concealed within the denticulate ligament or adventitia of the vertebral artery. The authors hope the data presented here will aid neurosurgeons and decrease complications in patients who undergo neurotomy for spasmodic torticollis. [ABSTRACT FROM AUTHOR]

Introduction. The vein of Labbé is an important structure of the lateral cortical surface. However, to date, studies aimed at providing external landmarks for aiding in its identification have been scant. Therefore, the present study focussed on establishing reliable bony landmarks for localizing this deeper lying venous structure. Materials and methods. Fifteen adult cadavers (30 sides) underwent dissection of the lateral cortical brain surface with special attention given to the drainage site of the vein of Labbé into the transverse sinus. Measurements of the distance from this site to surrounding external bony landmarks were then made. Results. We found that this drainage site into the transverse sinus was 0.8-1.5 cm (mean 1.1 cm, SD 0.567) superior to the superior border of the zygomatic arch and 2 - 5 cm (mean 2.9 cm, SD 0.713) posterior to the opening of the external auditory meatus. Statistically, there was no significance between left and right sides or between sexes. Conclusions. We found that the junction between the vein of Labbé and transverse sinus may be variable. Nonetheless, additional landmarks found in this study for identifying the junction may aid in its earlier identification during surgery, potentially decreasing operative morbidity. [ABSTRACT FROM AUTHOR]

The decision-making process surrounding resection of arteriovenous malformations (AVMs) in proximity to vital brainstem structures is a complex topic. Intricate vasculature in the setting of exquisite brainstem eloquence creates a high-risk operative landscape with the potential for devastating complications. Effective resections are driven by mastery of the relevant operative anatomy, preservation of pertinent vasculature, and technical experience and acumen. This article provides a narrative literature review on the resection of brainstem AVMs. Operative anatomy and approaches to AVMs of the midbrain (anterior/posterior), pons (anterior/lateral), and medulla (anterior/lateral) are discussed herein, with a focus on pearls and pitfalls for minimizing complications during resection. Careful consideration of the patient's clinical background, the natural history of the lesion, and expertise of the treating surgeon are paramount for improving the natural course of brainstem AVMs. [ABSTRACT FROM AUTHOR]