Morphometric Analysis of the Supraorbital Foramen and Notch in the Population of Bosnia and Herzegovina.

OBJECTIVE: The aim of this study was to learn about the morphological characteristics of the supraorbital foramen and to determine its precise position in relation to the surrounding anatomical landmarks in the adult population of Bosnia and Herzegovina. MATERIAL AND METHODS: For this purpose, 60 skulls from the Bosnia and Herzegovina population of known sex (32 males and 28 females), taken from the osteological collection of the Department of Human Anatomy of the Medical Faculty in Sarajevo, were subjected to morphological and morphometric analysis. Morphometric measurements were performed using a digital vernier caliper (Mitutoyo Corporation, Japan). RESULTS: The study showed that most supraorbital nerves exit the orbit through the supraorbital notch (73.8%) and the rest through the foramen (26.2%). Of this number, bilateral supraorbital notches were recorded in 58.33% of cases, a bilateral supraorbital foramen in 18.34% of cases, while in 23.33% of cases a notch was recorded on one side and a foramen on the contralateral side. Morphometric measurements performed to determine the exact position of the supraorbital foramen relative to the surrounding landmarks showed different values in males and females. An accessory foramen was also observed on the examined skulls in 16.67% of cases. CONCLUSION: Detailed knowledge of anatomical variations of the supraorbital foramen is required for safe and successful administration of regional anesthesia, in order to avoid iatrogenic nerve injuries during orbitofacial region surgery.

Anatomical Variations of the Supraorbital and Supratrochlear Nerves: Their Intraorbital Course and Relation to the Supraorbital Margin.

BACKGROUND This study aimed to describe the topographical anatomy of the supraorbital and supratrochlear nerves. Anatomical variations of both the intraorbital course of the 2 nerves and their relation to the supraorbital margin were analyzed. MATERIAL AND METHODS The research material involved 50 isolated adult cadaveric hemi-heads and 25 macerated adult skulls. All studied specimens were of Caucasian origin. RESULTS Taking into account the location of the frontal nerve division, 2 main variants of the intraorbital course of the supraorbital and supratrochlear nerves were distinguished. The first variant (variant I, 42%) involved cases in which the supraorbital and supratrochlear nerves branched off from the frontal nerve in the distal half of the length of the orbit. In the second variant (variant II, 58%), the frontal nerve branched into the supraorbital and supratrochlear nerves in the proximal half of the orbit. Variant II was characterized by the presence of a thick supraorbital nerve and a long, tiny supratrochlear nerve. For variant I, 27.8% of the supraorbital nerves were divided into the medial and lateral branch within the orbit, whereas, for variant II, 75% of nerves were divided into the medial and lateral branch within the orbit (before crossing the supraorbital margin). Single passage was observed on the supraorbital margin in 80% of wet specimens and in 78% of orbits examined on the macerated skulls. CONCLUSIONS Both the intraorbital and extraorbital course of the branches of the supraorbital and supratrochlear nerves were highly diverse. These variations should be taken into account during medical procedures performed within the orbital and frontal regions.

Visualization of the supraorbital notch/foramen using magnetic resonance imaging.

The supraorbital notch/foramen involving the segment of the supraorbital nerve (SON) and the supraorbital artery (SOA) has little been explored with magnetic resonance imaging (MRI). Therefore, we explored these structures using MRI. A total of 90 patients underwent thin-sliced contrast MRI. In addition, eight sides of the orbits were dissected in four cadaveric heads. Cadaver dissections showed that the SOA coursed consistently beneath and in close proximity to the SON and reached the supraorbital notch/foramen. On axial MRI images, the supraorbital notch/foramen was identified in 98% on the right side and in 99% on the left. The distance from the midline to the midpoint of the supraorbital notch/foramen and depth from the skin surface to the supraorbital foramen/exit were measured. The median distance was 22.6 ±â€¯3.08 mm on the right side and 22.8 ±â€¯3.07 mm on the left, whereas the depth was 7.7 ±â€¯1.39 mm on the right and 7.7 ±â€¯1.43 mm on the left. Eighty percent of the sagittal images showed well-developed diploic veins in the supraorbital rim. Of these, 8.3% had anastomotic channels with the subcutaneous veins through the anterior wall of the supraorbital rim, 11.8% through the inferior wall, and 9% through the SOF. The SON and SOA segments passing through the supraorbital exit can be reliably located using contrast MRI. The supraorbital rim may function as the intracranial to extracranial anastomotic channel.

Radiological management of the exiting points of supraorbital region neurovascular bundles / Manejo radiológico de los puntos de salida de los haces neurovasculares de la región supraorbitaria

SUMMARY: A preoperative computed tomography scan is useful to determine neurovascular exit points from orbit to supraorbital region. Determining the structure of exiting points (absence or presence, if present, being in form of foramen or notch) is important to plan the surgical approach. The aim of the study was to provide the radiological data by multi-detector computed tomography for estimating exiting points of the neurovascular bundles of the supraorbital region whether through foramen or notch in living subjects related to side (right/left), sex and age. Computed tomography examinations of 214 (102 male and 112 female) adult patients, aged average 44.2 ± 14 years, were evaluated, retrospectively. Presence or absence, number and nature (foramen/notch) of exiting points of neurovascular bundles were noted in each side regarding sex and age groups. The distance of foramen/notch to the midline of the face was recorded. Single notch was seen on the right in 123 and in 134 on the left, single foramen was seen in 62 on the right and in 56 on the left side and double foramen was seen in 13 on the right and in 6 on the left. The absence was seen in 16 on the right and 18 on the left side. No significant difference was seen on frequency compared between the sexes and age groups. Foramen was seen in 58 sides unilaterally and in 39 sides bilaterally. Notch was unilateral in 75 sides and bilateral in 95 sides. It was shown that males had a wider distance between right side foramen and left side notch to midline. Age groups did not show a significant difference in terms of side. Absence and foramen presence made up about 30-40 % of cases. Notch was the most common form. Foramen/notch presence was statistically unaffected by the sex and age factors. In terms of surgery, preoperative assessment of orbital exit points with computed tomography is essential.

RESUMEN: Una tomografía computarizada preoperatoria es útil para determinar los puntos de salida neurovascular en la región supraorbitaria. Para la planificación del abordaje quirúrgico es importante determinar la estructura de los puntos de salida (ausencia o presencia en forma de foramen). El objetivo de este estudio fue proporcionar los datos radiológicos mediante tomografía computarizada de detectores múltiples, para estimar los puntos de salida de los haces neurovasculares de la región supraorbitaria, ya sea a través del foramen o incisura en sujetos vivos relacionados con lado (derecho/izquierdo), sexo y edad. Se evaluaron retrospectivamente los exámenes de tomografía computarizada de 214 adultos (102 hombres y 112 mujeres), edad 44,2 ± 14 años. Se observó, en cada lado, presencia o ausencia, número y naturaleza (foramen / incisura) de los puntos de salida de los haces neurovasculares en cuanto a sexo y grupos de edad. Se registró la distancia del foramen / incisura al plano mediano de la cara. Se observó un foramen a la derecha en 123 de las tomografìas y en 134 a la izquierda, se observó un foramen simple en 62 a la derecha y en 56 en el lado izquierdo y se visualizó forámenes doble en 13 tomografías a la derecha y en 6 a la izquierda. Se observó ausencia en 16 casos a la derecha y 18 casos a la izquierda. No existió diferencia significativa en la frecuencia comparada entre los sexos y los grupos etarios. El foramen se detectó en 58 lados unilateralmente y en 39 lados bilateralmente. Se demostró que los hombres tenían una distancia mayor entre el foramen del lado derecho y el foramen del lado izquierdo hasta el pno mediano. No se observó una diferencia significativa en los diferentes grupos etarios en términos de lado. La ausencia y la presencia de los forámenes constituían alrededor del 30-40 % de los casos. Los factores de sexo y edad no afectaron estadísticamente la presencia del foramen / incisura. En términos de cirugía, la evaluación preoperatoria de los puntos de salida orbitales con tomografía computarizada es esencial.

The sensory innervation of the calvarial periosteum is nociceptive and contributes to headache-like behavior.

Headaches are thought to result from the activation and sensitization of nociceptors that innervate deep cephalic tissues. A large body of evidence supports the view that some types of headaches originate intracranially, from activation of sensory neurons that innervate the cranial meninges. However, the notion of an extracranial origin of headaches continues to be entertained, although the identity of deep extracranial cephalic tissues that might contribute to headaches remains elusive. Here we employed anatomical, electrophysiological, and behavioral approaches in rats to test the hypothesis that the sensory innervation of the calvarial periosteum is nociceptive. Neural tracing indicated that the calvarial periosteum overlying the frontal and parietal bones is innervated primarily by small and medium-sized neurons in the trigeminal ganglion's ophthalmic division. In vivo single-unit recording in the trigeminal ganglion revealed that calvarial periosteal afferents have slowly conducting axons, are mechanosensitive, and respond to inflammatory mediators, consistent with a nociceptive function. Two distinct neuronal populations were distinguished based on their peripheral axonal trajectory: one that reached the periosteum through extracranial branches of the trigeminal nerve, and another that took an intracranial trajectory, innervating the cranial dura and apparently reaching the periosteum via the calvarial sutures. In behavioral studies, inflammatory stimulation of these afferents promoted periorbital tactile hypersensitivity, a sensory change linked to primary headaches. Activation and sensitization of calvarial periosteal afferents could play a role in mediating primary headaches of extracranial and perhaps also intracranial origin, as well as secondary headaches such as postcraniotomy and posttraumatic headaches. Targeting calvarial periosteal afferents may be effective in ameliorating these headaches.

Long-term significance of injury to the supraorbital or supratrochlear nerves during frontoorbital advancement in infancy.

INTRODUCTION: In a series of 26 infants undergoing frontoorbital advancement in their first year of life, the supraorbital and supratrochlear nerves were not preserved during surgery in nearly all cases. Of these 26 patients, 25 could be followed up postoperatively. RESULTS: None of the children spontaneously complained of any sensory disturbances thereafter. In neurologic follow-up examinations or telephone interviews 11-81 (median, 39) months after surgery, the patients, respectively their parents were explicitly asked for sensory deficits. The majority of patients had no sensory disturbances at all; two patients reported on dysesthesias when touching the forehead, not affecting them in their daily life. CONCLUSIONS: It is concluded that (1) anatomical transsection of the supraorbital or supratrochlear nerve in very young patients may be functionally fully compensated over time, (2) the preservation of the supraorbital or supratrochlear nerve in frontoorbital advancement in patients less than 1 year of age is of no major significance in the long term and (3) partial anatomical preservation with functional impairment of the nerves may result in dysesthesias in the forehead. Therefore, from a practical surgical standpoint, deliberate anatomical transsection in this age group may be superior to partial morphological preservation of the nerves with subsequent functional impairment.

Characterization and localization of the supraorbital and frontal exits of the supraorbital nerve in Chinese: an anatomic study.

PURPOSE: To elucidate the characteristics and location of the supraorbital and frontal exits of the supraorbital nerve in Chinese skulls and to compare these findings with other ethnic populations. METHODS: The anatomy of the supraorbital nerve exits was studied in 97 adult Chinese skulls (194 orbits). The characteristics and location of the supraorbital nerve exits were determined. Analyses were performed to compare differences between sexes and sides. Data were then compared with those of the other populations. RESULTS: Supraorbital exits were found in all 194 orbits. Among these, 89 (45.9%) were foramina. Frontal exits were found in 69 of the 194 (35.6%) orbits in which 18 were foramina (9.3%). The location of the supraorbital exits showed a skewed distribution toward the medial aspect of the superior orbital rim. The median distance between the supraorbital exits and the facial midline was 24.56 mm. Eighty percent of the supraorbital exits lay between 20.77 mm and 30.52 mm from the facial midline. The mean frontal exit was 7.02 mm medial to the supraorbital exits. Compared with other populations, a higher proportion of Chinese have foramina above the superior orbital rim as the exits for the supraorbital neurovascular bundle. The location of the supraorbital nerve exit is highly variable in all studied populations. CONCLUSIONS: In a significant proportion of Chinese, the supraorbital nerve exits are located toward the medial aspect of and above the superior orbital rim. Extra care should be taken during dissection around this region to avoid damage to the supraorbital nerve.

Anatomical variations of the frontal and supraorbital transcranial passages.

In this study, 500 frontal and supraorbital transcranial passages were studied in 50 cadavers and 200 crania of 500 samples. One hundred six specimens had a frontal foramen (notch), and all the samples had a supraorbital foramen (notch). The frontal passage was a foramen in 7 samples and a notch in 99 samples. As for the supraorbital passage, it was found as a foramen in 133 of specimens and as a notch in 358 of specimens. In 9 of the specimens, there were double notches or foramina. The distances from the foramina (notches) to angulus oculi medialis were measured in the cadavers. The average distance from the angulus oculi medialis to the frontal foramen (notch) was 4.50 mm, and the average distance to the supraorbital foramen (notch) was 9.87 mm. The distances from the foramina (notches) to the midline were measured in the crania. The average distances from the midline to the frontal foramen (notch) and the supraorbital foramen (notch) were 20.24 mm and 25.23 mm, respectively. The average distance between the frontal foramen (notch) and supraorbital foramen (notch) was 5.37 mm in cadavers and 4.99 mm in crania. In 200 crania, the distances of the frontal and supraorbital transcranial passages to the midline were measured. Types of these passages were also evaluated, and frequencies were calculated. Measurements were made using a digital compass, and the student t test was used in the statistical evaluation of results.

Frequency variations of discrete cranial traits in major human populations. IV. Vessel and nerve related variations.

This concludes a series of descriptive statistical reports on discrete cranial traits in 81 human populations from around the world. Four variants classified as vessel and nerve related characters were investigated: patent condylar canal, supraorbital foramen; accessory infraorbital foramen; and accessory mental foramen. A significant asymmetric occurrence without any side preference was detected for the accessory mental foramen. Significant intertrait associations were found between the accessory infraorbital and supraorbital foramina in the panPacific region and Subsaharan African samples. The intertrait associations between the accessory infraorbital foramen and some traits classified as hypostotic were found mainly in the samples from the western part of the Old World, and those as hyperostotic traits in the samples from eastern Asian and the related population samples. With a few exceptions. the occurrence of a patent condylar canal and a supraorbital foramen was predominant in females, but the accessory infraorbital and accessory mental foramina were predominant in males. The frequency distributions of the traits showed interregional clinality and intraregional discontinuity. A temporal trend was found in the Northeast Asian region in the frequencies of the accessory infraorbital and accessory mental foramina. The diversity of modern human discrete cranial traits may at least in part be attributable to differential retention or intensification from an ancestral pattern.

The frontotemporal peripheral nerves. Topographic variations of the supraorbital, supratrochlear and auriculotemporal nerves and their possible clinical significance.

The peripheral topography of the supraorbital (SON) and supratrochlear (STN) nerves and the superficial temporal branch of the auriculotemporal nerve (ATN) was investigated in 10 cadavers. The aim was to define the optimal locations for anaesthetic nerve blocks, as well as to help surgeons prevent nerve injuries. Specific measurements on the nerve "exits" in relation to defined landmarks are presented. The variability of the supraorbital notches and peripheral branching of the dissected nerves suggests several methods for anaesthetic blocks in cases of surgical and clinical head pain. The optimum injection site for a selective SON block is 20-30 mm from the midline (range 15-33 mm); reinjection at 30-50 mm from the midline might complete inefficient nerve block. For selective SON block the distance between the main SON and STN branches (mean 15.3 mm) should also be considered. The ATN is best blocked at a point located at the level with and 10-15 mm (range 8-20 mm) anterior to the upper origin of the helix. Separate exits for the medial and lateral SON branches were observed in eight of the 20 nerves examined. Twenty of the 28 exits were foraminae completed by bony or connective tissue. In many cases both the SON and STN ascended close to the associated artery: in six cases a tissue band covered the nerve and vessel at the orbital exit. Some of the observed structures associated with the nerve might be pain-generators, however the present study does not provide any evidence for such a hypothesis.

Variations of the frontal exit of the supraorbital nerve: an anatomic study.

Until now, it has been taken for granted that the point of emergence of the supraorbital nerve is by way of a notch or a foramen at the border of the inner to the medial third of the supraorbital rim. In contrast to several anatomic textbooks, we noticed that the exit point was repeatedly not at the site where anticipated when implanting lid springs for facial palsy. This gave us the idea of investigating these variations and how big they are, because most open and recent endoscopic forehead lift techniques have relied on a constant exit point of the supraorbital nerve. A total of 507 macerated skulls (1014 orbits) from three anatomic collections in Austria and Germany were studied. All skulls were adult European skulls gathered from the prehistoric age up to the twentieth century. Additionally, 18 fixed cadavers (36 orbits) and 25 fresh cadavers (50 orbits) were studied. These data were not included in the statistical analysis but in the discussion. The anatomic measurements on the skulls were carried out with an anthropometric calliper. The examinations concentrated on the configuration (notch/foramen) and the number of exit point(s) on the supraorbital rim, the vertical distance from the supraorbital rim, and the distance from the nasion to the various exit point(s). Combining all of these parameters, 74 percent of the skulls showed asymmetric findings between the right and left orbits. In 15 percent of both orbits, the supraorbital nerve left the orbital cavity already in its two branches, the medial and lateral branch, either through a notch or a foramen, the foramen being sometimes the exit of a supraorbital canal. The average distance from the nasion to the frontal notch/foramen was 25 mm on both orbits (range 16 to 55 mm) and to the supraorbital notch/foramen 31 mm (range 20 to 49 mm). The largest vertical distance from the supraorbital rim to its farthest exit point was 19 mm. Other than what is cited in literature, the variations concerning the configuration and the distance of the exit point(s) of the supraorbital nerve were so significant that all forehead operations, especially those using endoscopic techniques, must take into account these findings.

The temporal branch of the facial nerve: how reliably can we predict its path?

A thorough examination of the temporal branch of the facial nerve was performed to characterize precisely the number of rami crossing the zygomatic arch and their location with respect to bone and soft-tissue landmarks. Fresh cadaver dissection was performed in 12 facial halves, dissecting the facial nerve superiorly from the stylomastoid foramen to identify all branches crossing the zygomatic arch. There were a median of three (range two to four) rami of the temporal branch crossing the lower aspect of the zygomatic arch, with distinct anterior and posterior divisions identified in each dissection. In 8 of the 12 dissections, one or more separate middle divisions of the nerve also were seen at the inferior aspect of the zygomatic arch. Superior to the zygomatic arch, frequent interconnections were noted between all divisions of the temporal branch, but no connections were noted to other branches of the facial nerve. Previous descriptions of the course of the temporal branch based on soft-tissue landmarks most closely correlated with nerve rami that were found in the present study to be located within the anterior division of the nerve. On crossing the inferior aspect of the zygomatic arch, the anterior and middle divisions of the temporal branch were located a median of 12 and 4 mm anterior to the articular eminence, respectively; the posterior division ranged in location from 10 mm posterior to 7 mm anterior to the articular eminence. The range over which rami of the temporal branch crossed the inferior aspect of the zygomatic arch was equally divided anterior and posterior to the articular eminence and covered up to 50 percent of the total length of the zygomatic arch. The present study confirms that the temporal branch is not a single nerve branch but consists of multiple rami that cross the zygomatic arch anywhere for over half the length of its inferior border. Techniques for localizing the nerve based on reference points from two soft-tissue landmarks are therefore unreliable.

Transcranial approach to the orbit: microsurgical anatomy.

An anatomical study of three microsurgical intraorbital routes to the optic nerve and orbital apex, which can be reached through a fronto-orbital craniotomy, was conducted on cadaver specimens. The structures that could be exposed via the medial, central, or lateral approaches directed through the orbital roof were defined. The medial approach, directed through the space between the superior oblique and the levator muscles, provides good access to all parts of the intraorbital optic nerve. The central approach, between the levator and the superior rectus muscles, provides the shortest route to the optic nerve. Two variants of the central approach were examined. In the first, the levator muscle and frontal nerve are retracted medially and the superior rectus muscle laterally. This variant provides access to only the midportion of the intraorbital segment of the optic nerve. In the second variant, the frontal nerve is retracted laterally together with the superior rectus muscle. This variant provides access to the posterior two-thirds of the intraorbital portion of the optic nerve. The lateral approach is directed between the levator and lateral rectus muscles. This approach also has two variants, depending on whether the superior ophthalmic vein is retracted medially or laterally. The variant in which the superior ophthalmic vein is retracted medially with the levator and superior rectus muscles provides access to the lateral side of the optic nerve except in the region adjacent to the superior orbital fissure. The variant in which the superior ophthalmic vein is retracted laterally together with the lateral rectus muscle provides excellent access to the optic nerve in the region of the superior orbital fissure. It is an ideal approach for lesions that involve both the cavernous sinus and orbit.

Pedicle and antler development following sectioning of the sensory nerves to the antlerogenic region of red deer (Cervus elaphus).

Sensory nerves supplying the deer antlerogenic region were sectioned about 60 days prior to pedicle initiation to determine the extent of neural influence on pedicle and first antler growth. Our results from a combination of histological examination and immunohistochemical localization showed that all 12 antlerogenic regions were successfully deprived of sensory nerve supply, but in 10 of 12 cases there was partial regeneration during the experimental period. In the two cases where no sensory reinnervation occurred, pedicle growth did not show any differences compared with partially sensory reinnervated or intact pedicles. With or without reduced sensory nerve supply, first antlers were initiated, grown, cleaned of velvet, cast, and regenerated in the normal way, but they were smaller than controls. Consequently, we conclude that a sensory nerve supply is not necessary for normal pedicle formation and for the first antler cycle, but plays a role in determining antler size.

Comparison of residual osseous mass between vascularized and nonvascularized onlay bone transfers.

Composite flaps containing vascularized frontal bone were transferred on muscle pedicles in immature rabbits. Vascular continuity was maintained on one side and interrupted on the other. Bone weights at 16 weeks following transfer were compared with those of unoperated controls. The conventional bone graft demonstrated significant reduction in osseous mass. The vascularized bone maintained its mass compared with unoperated controls. Vascularized bone transfer appears to be the preferred surgical technique whenever possible.