Localization of the supraorbital,infraorbital, and mental foramina using palpable,bony landmarks

The purpose of this study was to locate the infraorbital, supraorbital, and mental foramina by using palpable anatomical landmarks that are conducive to surgical use. Fourteen embalmed cadavers (27 sides) were dissected to expose the supraorbital, infraorbital, and mental foramina. Measurements were made from the lateral orbital rim at the zygomaticofrontal (ZF) suture to both the supraorbital and infraorbital foramina. The distance from the inferior orbital rim at the zygomaticomaxillary (ZM) suture to both foramina was also measured. The distance to the mental foramen was measured from the angle and the inferior border of the mandible. The supraorbital foramen was located 26.2 ± 2.8 mm medial and 13.5 ± 3.7 mm superior to the ZF suture. The infraorbital foramen was located 23.8 ± 3.1 mm medial and 30.9 ± 3.8 mm inferior to the ZF suture, on average. Vertical measurements made from the ZM suture to the supraorbital foramen averaged 34.4 ± 3.6 mm and from the ZM suture to the infraorbital foramina averaged 7.6 ± 2.2 mm. The mental foramen was 64.2 ± 6.4 mm medial to the angle of the mandible and 12.9 ± 1.6 mm superior to the inferior border of the mandible. This study provides data that may be useful in predicting the location of the supraorbital, infraorbital, and mental foramina using palpable landmarks. These data may be particularly helpful for surgery in patients with missing teeth or fractures of the maxillary bone. Clin. Anat., 2010. © 2009 Wiley‐Liss, Inc.     

The relative locations of the supraorbital,infraorbital, and mental foramina: A cadaveric study

The purpose of this study is to investigate the applicability of the current surgical guideline stating that the main facial foramina that transmit cutaneous nerves to the face (supraorbital notch/foramen, infraorbital foramen, and mental foramen) are equidistant from the midline in European and Hispanic populations. Previous studies suggest this surgical guideline is not applicable for all ethnicities; however, to our knowledge, no data have been published regarding the accuracy of this guideline pertaining to the Hispanic population. An experimental study was performed on 67 cadavers donated to the Human Anatomy Program at UT Health San Antonio. The supraorbital, infraorbital, and mental foramina were dissected and midline structures including the crista galli, internasal suture, anterior nasal spine, and mandibular symphysis were identified. The distance from each foramen to midline was recorded using a digital caliper. For all cadavers/ethnicities studied, the supraorbital, infraorbital, and mental foramina were 25.32 mm, 29.57 mm, and 25.55 mm to the midline, respectively. Thus, the infraorbital foramen is located significantly more lateral compared to the supraorbital (p < 0.0001) and mental foramina (p < 0.0001). After dividing the sample based on ethnicity, this relationship was also true for the European sample and tended to be true for the Hispanic sample. Significant anatomical variations exist in the current surgical guideline stating that the supraorbital foramen, infraorbital foramen, and mental foramen are equidistant from the midline. Clinicians may need to adjust their methodology during surgical procedures of the face in order to optimize patient care.     

The Localization of the Supraorbital Notch or Foramen is Crucial for Headache and Supraorbital Neuralgia Avoiding and Treatment

The aim of this study was to provide the morphological and morphometric data of the supraorbital foramina or notches related to sex, side, and the climatic conditions where the population lived. It was hypothesized that the distribution of the occurrence and location of these openings depends on climatic conditions in which the population lived. Orbits from 866 dried skulls obtained from three climatic regions: warm, temperate, and cold were examined. The examination concentrated on the configuration (notch/foramen) and on the distances to the reference points: nasion, frontomalare orbitale, infraorbital foramen and the superior orbital rim. In 14.3% of cases a smooth supraorbital rim was observed while different variants of the structures were observed in 85.7% of the cases. In cold climatic conditions, supraorbital foramina were found in the highest frequency (35.4%). In warm and temperate climates, the observed frequencies of supraorbital foramen were the lowest (18.8% and 19.9%, respectively). Frequency of supraorbital notches was the lowest of those skulls from a cold climate (44.0%) and the highest in those from a warm climate (59.0%). These results support the hypothesis that the occurrence of the supraorbital notches is greater in populations from warm compared with cold regions. This would provide a greater exit route for the neurovascular bundle and this may be related to the thermoregulatory processes in the supraorbital region. Furthermore, knowledge of precise locations of supraorbital structures is important when a supraorbital nerve block is given, for example, in the treatment of migraine headaches. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

应用鼻翼和口角定位眶下孔和颏孔的应用解剖学研究

目的：应用鼻翼和口角标记定位眶下孔和颏孔,为颌面外科手术避免损伤出入两孔的血管神经提供应用解剖学资料。方法：取30例10％甲醛溶液固定尸体头部标本,解剖暴露眶下孔和颏孔。眶下孔和颏孔测量点为各自中心点,鼻翼测量点为鼻翼外侧下脚。测量两侧眶下孔、颏孔、鼻翼及口角之间的距离,眶下孔和颏孔最大径,鼻翼至经眶下孔垂直线的垂直距离、眶下孔至经鼻翼水平线的垂直距离、眶下孔至鼻翼直线距离,口角至经颏孔水平线的垂直距离、颏孔至经口角垂直线的垂直距离、颏孔至口角直线距离。结果：眶下孔定位在鼻翼上方（13．9±3．6）mm,向外（6．7±2．8）mm处;眶下孔与鼻翼间直线距离为（16．4±3．2）mm。颏孔定位在口角下方（20．6±2．9）mm,向内（3．4±3．1）mm处;颏孔与口角间直线距离为（21．7±3．3）mm。结论：以鼻翼和口角为标记定位眶下孔及颏孔位置,有助于临床避免损伤出入两孔的血管神经。     

Morphometric measurements from various reference points in the orbit of male Caucasians

The aim of this study was to determine the morphometric variations from various reference points to decrease risks in orbital surgery. Sixty-two orbits obtained from 31 skulls of male adult Caucasians were measured with a millimetric compass. On the medial orbital wall, the midpoint of the anterior lacrimal crest was the reference point; from this point we measured distances of 23.9+/-3.3 mm, 35.6+/-2.3 mm, 41.7+/-3.1 mm and 6.9+/-1.5 mm respectively to the anterior ethmoidal foramen, posterior ethmoidal foramen, midpoint of the medial aspect of the optic canal and posterior lacrimal crest. On the same wall, distances from the plane of the anterior and posterior ethmoidal foramina to the ethmoido-maxillary suture and distance from the posterior ethmoidal foramen to the anterior ethmoidal foramen and midpoint of the medial margin of the optic canal were 14.9+/-2.3 mm, 9.8+/-2.9 mm and 6.8+/-2.2 mm respectively. On the inferior orbital wall, the main reference point was the infraorbital foramen, and from this point to the midpoints of the lateral margin of the fossa for the lacrimal gland, inferior orbital fissure, inferior orbital rim and inferior aspect of the optic canal was 23.8+/-7.2 mm, 31.9+/-3.9 mm, 6.7+/-1.9 mm and 50.3+/-3.2 mm respectively. On the superior orbital wall, the distances from the supraorbital foramen to the midpoints of the superior orbital fissure, fossa for the lacrimal gland and superior aspect of the optic canal were 45.7+/-3.6 mm, 26.0+/-2.5 mm and 45.3+/-3.2 mm respectively. Furthermore, on the same wall, the distance from the posterior ethmoidal foramen to the midpoint of the superior orbital fissure was 14.6+/-2.8 mm. Finally, on the lateral orbital wall the frontozygomatic suture was the reference point. From this point distances to the midpoints of the fossa for the lacrimal gland, superior orbital fissure, lateral aspect of the optic canal and inferior orbital fissure were 17.5+/-2.1 mm, 37.7+/-3.6 mm, 44.9+/-2.5 mm and 33.4+/-3.1 mm respectively.     

Anatomical study of the infraorbital foramen

Detailed knowledge of variations of the infraorbital foramen (IOF) and the establishment of a constant reference point for needle insertion are important for safe and successful regional block and for avoiding iatrogenic injury to the nerve during surgery in the midfacial region. Infraorbital foramina from 133 sides of 67 dry intact adult skulls of undetermined gender were examined for variations in shape, number, location in relation to bony landmarks, and relationship to the maxillary teeth. The angles of needle insertion in the sagittal and Frankfurt planes were determined. The infraorbital foramina were located at an average distance of 6.33 ± 1.39 mm below the infraorbital margin, 25.69 ± 2.37 mm from the median plane, 15.19 ± 1.70 mm from the lateral margin of the piriform aperture, and 28.41 ± 2.82 mm above the maxillary alveolar border. The average angles of needle insertion through the IOF with the sagittal and Frankfurt planes were 21.14° ± 10.10° and 31.79° ± 7.68°, respectively. Multiple foramina were found in 21% of the hemi‐skulls. The foramen was less than 2 mm in size in 23.31% of the hemi‐skulls. The position of the IOF with respect to the maxillary teeth varied from the interval between the canine and first premolar to the first molar, but in half of the specimens it lay in line with the second maxillary premolar tooth. The observations made in this study should be useful for planning infraorbital nerve block or surgery around the IOF. Clin. Anat. 28:753–760, 2015. © 2015 Wiley Periodicals, Inc.     

Variations of supraorbital traits

More than one notch and/or foramen may be found in the supraorbital region due to branching of the supraorbital nerves and vessels. A total of 360 adult Anatolian-Ottoman skulls (212 male, 148 female) were examined for some characteristics of the notches and/or foramina in the supraorbital region. The distribution of the supraorbital traits: 335 (93%) in medial, 24 (6.7%) in both medial and lateral, only 1 (0.3%) in lateral position. Of 360 skulls, 197 (54.7%) had one notch on either side, 32 (8.9%) had one foramen on one side and one notch on the other side, 24 (6.7%) had one foramen and notch on one side and one notch on the other side, 19 (5.3%) had one foramen on either side and 88 (24.4%) had other combinations. The distances of the notches from the midline, and between of the foramina from the midline and the supraorbital margin were measured. Knowledge of the anatomy of the supraorbital region is important for the plastic and maxillofacial surgery.     

Ultrasound imaging of the infraorbital foramen and simulation of the ultrasound-guided infraorbital nerve block using a skull model

Purpose

Infraorbital nerve block is used for intraoperative and postoperative analgesia in nasal and oral surgery procedures, as well as in the chronic pain settings. Ultrasound guidance has not been described in the literature. The aim of the study was to assess the quality of ultrasound imaging of the infraorbital foramen and develop an “in-plane” technique of the block using a skull model.

Methods

The infraorbital foramina were assessed on five skull models immersed in the water bath. Ultrasound-guided simulation of an in-plane infraorbital nerve block was then performed. Slightly curved needle was placed close to the foramina and its visibility was recorded. Success rate and time to locate infraorbital foramina, success rate and time to insert the needle close to the foramina under ultrasound and correlation between the ultrasound and caliper measurements were evaluated and recorded. Data for the left and right foramen were compared.

Results

The infraorbital foramina were successfully located using ultrasound in all 20 cases. Simulation of infraorbital nerve block was also successful in all measurements. The time difference between locating or simulating blockade of the left and right infraorbital foramina was not statistically significant. Correlation between ultrasound measurement and direct measurement using a caliper was satisfactory for the distances between the inferior orbital rim and the inferior margin of the infraorbital foramen but poor for the distances between the lower rim of the orbit and the superior margin of the foramen.

Conclusions

This experimental study suggests that the infraorbital foramen is easily located using ultrasound and an “in-plane” ultrasound-guided technique for infraorbital nerve blockade is feasible on the model.     

国人眼眶容积及骨性径线测量

目的　为眼眶手术安全和眼眶重建术提供形态学资料。方法　应用摩立逊定位仪、游标卡尺等工具对 30例骨性眼眶进行解剖测量。结果　眶外侧缘点至眶上裂距离为 35 2 5mm ;眶外侧缘点至视神经孔外侧缘距离为 4 8 4 0mm ;眶下点至眶上裂距离为 4 5 6 2mm ;眶下点至眶下裂距离为 19 5 8mm ;眶下点至视神经孔外侧缘距离为 5 2 0 8mm ;眶内侧缘点至筛前孔距离为 18 5 9mm ;眶内侧缘点至筛后孔距离为 32 4 9mm ;眶内侧缘点至视神经孔内侧缘距离为 4 1 15mm ;眶上切迹至眶上裂距离为 39 0 4mm ;眶上切迹至视神经孔上缘距离为 4 5 93mm ;眶上缘中点至视神经孔上缘距离为 4 7 13mm ;眶下点至眶上裂距离为 4 5 35mm ;眶下缘中点至视神经孔外缘距离为 4 9 6 4mm ;眶深为 4 9 6 4mm ;颅最大长度为 175 34mm ;眶容积为 2 7 0 0ml。结论　同一个体双侧眼眶除了眶下点至视神经孔外侧缘距离右眼大于左眼 (P =0 0 16 )外 ,其他无显著差异 ;眶深与颅最大长度无直线相关关系。     

眶下孔相关径线测量及定位研究

目的　测量完整人颅骨的眶下孔的相关径线,为临床应用提供数据。 方法　用游标卡尺测量60例（120侧）成人眶下孔内径的长径和短径,并观察孔的形状,观察副孔的数量。测量眶下孔到眶下缘的距离,切此线与面部前正中线平行。测量眶下孔到梨状孔外缘的距离,切此线与面部前正中线垂直。 结果　① 眶下孔为圆孔（10%）和椭圆形孔（90%）;②左右两侧眶下孔副孔总的出现率为2.5%。③眶下孔的长径为（4.24±0.91）mm（2.48~7.59 mm）。④眶下孔的短径为（2.55±0.48）mm（1.37~3.63 mm）。⑤眶下孔到眶下缘的距离为（8.54±1.60）mm（5.16~13.63 mm）。⑥眶下孔到梨状孔外缘的距离为（16.55±2.01）mm（11.73~23.17 mm）。 结论　完善人颅骨眶下孔的形态学资料,为临床开展眶下孔的应用研究提供数据。     

Anatomical Consideration of the Anterior and Lateral Cutaneous Nerves in the Scalp

To better understand the anatomic location of scalp nerves involved in various neurosurgical procedures, including awake surgery and neuropathic pain control, a total of 30 anterolateral scalp cutaneous nerves were examined in Korean adult cadavers. The dissection was performed from the distal to the proximal aspects of the nerve. Considering the external bony landmarks, each reference point was defined for all measurements. The supraorbital nerve arose from the supraorbital notch or supraorbital foramen 29 mm lateral to the midline (range, 25-33 mm) and 5 mm below the supraorbital upper margin (range, 4-6 mm). The supratrochlear nerve exited from the orbital rim 16 mm lateral to the midline (range, 12-21 mm) and 7 mm below the supraorbital upper margin (range, 6-9 mm). The zygomaticotemporal nerve pierced the deep temporalis fascia 10 mm posterior to the frontozygomatic suture (range, 7-13 mm) and 22 mm above the upper margin of the zygomatic arch (range, 15-27 mm). In addition, three types of zygomaticotemporal nerve branches were found. Considering the superficial temporal artery, the auriculotemporal nerve was mostly located superficial or posterior to the artery (80%). There were no significant differences between the right and left sides or based on gender (P>0.05). These data can be applied to many neurosurgical diagnostic or therapeutic procedures related to anterolateral scalp cutaneous nerve.     

除皱术中防止眶上神经损伤的解剖学基础

目的:为除皱术中防止眶上神经损伤提供解剖学依据。方法:10例防腐固定标本和5例新鲜标本,解剖观察眶上神经的走行、分布及毗邻,分析其分布特点及预防损伤的手术方法。结果:①按分布区域和解剖层次,眶上神经可分为外侧支(深支)、内侧支(浅支);②外侧支包含眶上神经主干和多数分支,以2-3支从眶上孔发出,或以单一束支从眶上孔发出,在走行过程中逐渐发出2-3支。67.7％的内侧支为细小分支,22.3％为单一束支;③眶上神经外侧支的外侧边界可走行在上颞线上,外侧支主干分布在上颞线及其内侧(1.6±0.2)cm范围内。结论:(1)眶上神经位于眶上孔与同侧额结节、上颞线连线间的区域内;(2)在额部除皱术中,合理设计切口,避免在上述区域内的腱膜下疏松结缔组织层分离可预防眶上神经损伤。     

Location and incidence of the zygomaticofacial foramen: An anatomic study

The location and incidence of the zygomaticofacial foramen (ZFF) was studied in 80 dry skulls (160 sides) of unsexed adult skulls of West Anatolian people. The average distances from the ZFF to the frontozygomatic suture, to the zygomaticomaxillary suture, and to the inferior orbital rim were found to be 26.2 ± 3.2 mm, 18.6 ± 3.14 mm, and 5.94 ± 1.43 mm, respectively. The zygomas were evaluated for the number of foramina on their facial aspects. There was none in 25 (15.6%), one in 71 (44.4%), two in 45 (28.1%), three in 10 (6.3%), four in seven (4.4%), and five in two (1.3%) sides. The ZFF was also studied for its distribution around the zygoma by dividing the surface into four anatomical areas. There was no statistical difference between the morphometrical results on both sides. Data regarding the location and variation in the number of the ZFF is important in avoiding zygomatic nerve and vessel injury during surgery, but by virtue of the great variability found, ZFF is an unreliable landmark for maxillofacial surgery. Clin. Anat. 22:559–562, 2009. © 2009 Wiley‐Liss, Inc.     

Lingual foramina on the mandibular midline revisited: a macroanatomical study

The purpose of the present study was to determine the incidence, size, location, course, and content of the foramina and bony canals located on the lingual side of the mandibular midline. Fifty dry human mandibles were morphometrically analyzed by measuring the distances of these midline foramina from the mandibular base and the dimensions of these foramina and their bony canals. In addition, macro- and microanatomical dissection was performed on 12 intact cadaver mandibles. The macroanatomic midline foramina were classified into superior and inferior genial spinal foramina according to their vertical location with respect to the genial spines. This study showed that out of 50 dry mandibles, 49 (98%) had at least one midline lingual foramen; only one lacked a true midline foramen. Evaluation of the microanatomical dissections indicated a clear neurovascular bundle in both superior and inferior genial spinal foramina and canals. For the superior canal, the content was found to derive from the lingual artery and the lingual nerve. For the inferior canal, however, the arterial origin was submental and/or sublingual, while the innervation derived from a branch of the mylohyoid nerve. In conclusion, different kinds of lingual foramina have been identified according to their location. The superior and inferior genial spinal foramina have different neurovascular contents, determined by their anatomical location above or below the genial spines.     

Incidence and morphological study of zygomaticofacial and zygomatico-orbital foramina in dry adult human skulls: the non-metrical variants

Morphological diversity in the form of multiple zygomaticofacial (ZF) foramina was studied in 165 dry, unsexed adult human skulls. Zygomatic bones revealed variation in the number of foramina on their orbital and facial aspects. These were absent in 72 (21.8%) sides. A single ZF foramen was seen in 148 (44.9%) sides. Two ZF foramina were found in 92 (27.9%) sides, out of which 29 (8.8%) sides had one zygomatico-orbital (ZO) foramen, while 63 (19.1%) sides had two ZO foramina. Three ZF foramina, a relatively uncommon occurrence, were found in 17 (5.1%) sides, which included eight (2.4%) sides with one less and nine (2.7%) sides with the same number of ZO foramina. Four ZF foramina were seen in one (0.3%) side with three on the orbital aspect, a feature not reported before. The zygomatic nerve may be disrupted on elevating periorbita from the lateral wall during orbital surgery, and care should be taken to prevent injury to the nerve during the lateral orbitotomy approach to access intraorbital soft tissue tumors.     

Nerve root to lumbar disc relationships at the intervertebral foramen from a surgical viewpoint: An anatomical study

The objective of this study was to analyze relationship of the intervertebral disc to the nerve root in the intervertebral foramen. Fourteen formalin-fixed cadavers were studied and measurements were performed. At the medial line of the neural foramen, the disc-root distance gradually increased from L1-L2 to L5-S1. The shortest distance between the disc to nerve root was L1-L2 (mean, 8.2 mm) and the greatest distance was found at L3-L4 (mean, 10.5 mm). In the mid-foramen, the disc-root distance decreased from L1-2 to L5-S1. The shortest distance from the disc to nerve root was found at L5-S1 (mean, 0.4 mm); and the greatest distance, at L1-L2 (mean, 3.8 mm). For the lateral line, the distance between an intersection point between the medial edge of the nerve root and the superior edge of the disc and lateral line of the foramen consistently increased from L1-L2 to L5-S1. The shortest distance from nerve root to the lateral border of the foramen, at the point where the nerve root crosses disc was at level L1-L2 (mean, 2.6 mm), the greatest distance, L5-S1 (mean, 8.8 mm). The width of the foramina progressively increased in a craniocaudal direction (mean, 8.3-17.8 mm from L1-2 to L5-S1, respectively). The mean height of the foramina was more or less the same for disc levels (range, 19.3-21.5). The results showed that nerve roots at lower levels traveled closer to the midline of the foramen. This morphometric information may be helpful in minimizing the incidence of injury to the lumbar nerve root during foraminal and extraforaminal approaches.     

Anatomical study of the supraorbital and supratrochlear nerves: A new classification and application to understanding some migraine headaches

The frontal nerve is the largest branch of the ophthalmic nerve. This nerve gives rise to two terminal branches, the supraorbital (SON) and supratrochlear nerves (STN). To the best of our knowledge, there are no reports describing the detailed proximal course of these nerves while inside the orbit. Therefore, the goal of this study was to clarify the anatomy of the SON and STN inside and at their exit from the orbit. Twenty sides from ten fresh-frozen cadavers were used in this study. Intra and extra orbital dissections were performed to observe the course of the SON and STN. Additionally, measurements of the nerves were made at these locations. The course of the SON and STN inside the orbit was classified into three groups depending on the STN branching pattern from the SON. The group without any branch from the SON and STN inside the orbit was the most common. The exit points of these nerves were via the supraorbital notch, foramen, or neither a notch nor foramen. A distinct fibrous band was consistently found tethering the nerve except in specimens with nerves traversing a bony foramen. The mean diameters of the SON and STN were 1.3 ± 0.2 and 0.7 ± 0.1 mm, respectively. The results of this study further our knowledge of the course and morphology of the SON and STN and might be useful for better understanding and potentially treating some forms of migraine headache due to SON or STN compression/entrapment. Clin. Anat. 33:332–337, 2020. © 2019 Wiley Periodicals, Inc.     

Variations in size and in symmetry of foramina of the human skull.

The goal of this report is to define an average size and size range for many of the skull's foramina and to determine in which paired foramina asymmetry is commonly found so that researchers and clinicians examining foramina may have an anatomical reference. The incidence of foraminal variations is also discussed. Information on skull foraminal size and symmetry is increasingly important because of the advancements in radiologic techniques such as magnetic resonance imaging (MRI) and computed tomography (CT). These methods are making difficult diagnoses of pathologic conditions of skull foramina possible. The foramina of 100 randomly selected dry skulls were measured and the symmetry of paired foramina was noted. The average, largest, and smallest sizes for 29 different foramina and the length of one canal are listed. Information regarding the symmetry of 27 paired foramina and the length symmetry of the infraorbital canal was also gathered. Specific data collected for paired foramina include the percent of skulls in which (1) neither foramen of the pair was present, (2) both foramina of a pair were present, (3) both foramina of the pair are present and were both the same size within 0.5 mm, and (4) both foramina of a pair are present but there was greater than 0.5 mm difference in size between them.     

The meningo-orbital foramen in a Scottish population

The meningo-orbital foramen is a small opening in the orbit lateral to the lateral end of the superior orbital fissure. It is widely reported to contain an orbital branch of the middle meningeal artery. The foramen may be single or multiple and may occur in the posterosuperior part of the lateral orbital wall or in the posterolateral part of the orbital roof. There is a lack of clarity in the literature as to whether foramina occurring in the orbital roof are the same entity as those occurring in the lateral wall. The disposition of the lesser wing of the sphenoid at the anterior limit of the middle cranial fossa makes it difficult to see how a foramen communicating with the anterior cranial fossa could transmit a branch of the middle meningeal artery. Our study contained 16 meningo-orbital foramina in the orbital roof that would transmit a fine probe. Fourteen of these passed into canals that tracked posteriorly in the bone to open into the middle cranial fossa close to the lateral extremity of the superior orbital fissure. The other two of these foramina communicated with the anterior cranial fossa and both were associated with a more posterior foramen that communicated with the middle cranial fossa. We hope this study clarifies an issue with relevance to surgery in the anterior cranial fossa.