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Background: The external opening of the carotid canal (EOCC), the entry point of the internal carotid artery into the skull, varies across populations. This study characterized the EOCC with the mastoid process (shortest distance from the EOCC to the tip of the mastoid process [SDTCC]), the foramen magnum (shortest distance from the EOCC to the foramen magnum [SDFM]), and the midline of the skull base (shortest distance from the EOCC to the midline of the base of the skull [SDMCC]) in the Nigerian population. Materials and Methods: Fifty skull base pictures were taken in the plumed position with a digital camera. Measurements were taken using Image J software, and Euclidean distances were calculated. The shapes of the EOCC were noted. Paleontological Statistics (PAST 3.0) was used to perform descriptive statistics. Paired t-test and Pearson correlation were used to compare bilateral values and the relationship between the parameters, respectively. Results: The length (right, 0.53 [standard deviation (SD)=2.5] mm; left, 10.99 [SD=2.84] mm) and width (right, 13.96 [SD=2.43] mm; left, 14.16 [SD=2.09] mm) of the EOCC were recorded. In contrast to the populations in South Africa, Serbia, and India, the length of the EOCC obtained from this study is shorter than the breadth. The length of SDFM (right, 41.04 mm; left, 44.13 mm), SDMCC (right, 58.4 mm; left, 57.97 mm), and SDTCC (right, 57.29 mm; left, 55.61 mm) was established among Nigerians. Conclusion: The Nigerian population showed EOCC of shorter length than the breadth compared to other populations, and the size of the skull is independent of the foramina size. These dimensions may provide information for procedures that affect the skull base.

Many studies revealed that the sphenoid sinus pneumatization (SSP) affects the protrusion/dehiscence of adjacent structures including optic canal (OC), foramen rotundum (FR), vidian canal (VC), and carotid canal (CC). Knowledge of this relationship bears vital importance to identify the safest surgical route during transsphenoidal procedures. Therefore, we aimed to determine the individualized prevalence of the protrusion/dehiscence of adjacent structures based on sagittal and coronal SSP (SSSP and CSSP) patterns. Computed tomography images of 300 patients were analysed to identify the SSSP and CSSP types, and the protrusion/dehiscence of adjacent structures was determined. The relationship between the variables was examined using statistical analysis in terms of age, gender, and laterality. The most prevalent SSSP type was postsellar (62.7%), followed by sellar (30%), presellar (6.6%), and conchal (0.7%). In 71.3% of patients, five types of CSSP were observed, with 23.6% and 21.7% exhibiting Type IV and V, respectively. Our results indicated that postsellar type, Type IV and V CSSP associated with the highest likelihood of protrusion/dehiscence of OC, FR, VC, and CC. Furthermore, no significant correlation was observed between these qualitative variables and gender, with the exception of the VC dehiscence, the protrusion of OC and CC. No notable differences were identified with respect to laterality. Also, the probability of having postsellar type, Type IV and V CSSP, as well as the protrusion of OC, VC, and CC, decreased with increasing age. Further detailed analysis of this association is required to predict the size of the surgical window and to prevent neurovascular injury. [ABSTRACT FROM AUTHOR]

Abstract Background Sphenoid sinus (SS) is an important landmark for endoscopic sinus surgery (ESC) and endoscopic skull base surgery. This study examines the relation of the extent of pneumatization of the sphenoid sinus with adjacent vital structures such as the internal carotid artery, optic canal, and Vidian nerve by using paranasal sinus computed tomography (PNSCT). Methods The study was designed retrospectively. PNSCT images in axial, coronal, and sagittal planes on both sides (right, R; left, L) were examined for sphenoid sinus, Vidian canal (VC), optic canal (OC), and carotid canal (CC) bilaterally. Results The carotid canal did not show identification on the SS wall in females compared to males bilaterally (right, p= 0.002 and left, p= 0.002). The mean age was significantly higher in patients with a presellar type of sphenoid sinus (p=0.003). The mean age was significantly lower on the right side with a VC completely within the sphenoid sinus (p=0.005). The mean age of patients with an optic canal protrudation to the SS wall was significantly higher than patients with an optic canal indentation to the SS wall (p= 0.007). On the left side, cases with an optic canal protruding to the SS wall were older than cases with an optic canal indentation to the SS wall (p= 0.008). SS variations on the sagittal plane were significantly correlated with RVC, RCC, LVC, and LCC variations. Also, SS variations on the coronal plane were significantly related to types of LVC and RVC. Conclusions Pneumatization of SS significantly affects the development of surrounding vital structures, especially with increasing age.

AbstractObjectivesMethodsResultsConclusionWe investigated the relationship between sphenoid sinus (SS) pneumatization types, carotid canal types and carotid canal–intersinus septa connection.The paranasal sinus computed tomography (PNSCT) images of 274 patients (141 males and 133 females) were evaluated retrospectively. SS pneumatization, SS intersinus septation, SS intersinus septa deviation, carotid canal classification, carotid canal dehiscence, carotid canal–intersinus septa connection and presence of Onodi cells were evaluated.In presellar and sellar SS, type 1 carotid canal was detected. However, type 3 carotid canal was detected more in postsellar SS. On the left side, in 26.4% of the postsellar SS, carotid canal dehiscence was detected. On the right side, carotid canal-intersinus septa connection was detected in 55.8% of the postsellar SS and 35.1% of the sellar SS. On the left side, it was detected 58.3% of the postsellar SS and 30.9% of the sellar SS. In postsellar type SS pneumatized cases, right caroid canal-intersinus septa connection increased by 5.4 fold and left carotid canal-intersinus septa connection increased by 7.3 fold compared to presellar type SS pneumatization. In 2≥ intersinus septa group, left carotid canal-intersinus septa connection increased 5.0 fold compared to ‘no septa’ group.In this study, we evaluated SS pneumatization types and their relation with carotid canal types and carotid canal-intersinus septa connections. Type 3 carotid canal (protrudation to SS wall) was detected more in postsellar SS. In these cases, surgeons should be very careful during surgery to avoid damage to the internal carotid artery (ICA). [ABSTRACT FROM AUTHOR]

Background: Sphenoid sinus (SS) is an important landmark for endoscopic sinus surgery (ESC) and endoscopic skull base surgery. This study examines the relation of the extent of pneumatization of the sphenoid sinus with adjacent vital structures such as the internal carotid artery, optic canal, and Vidian nerve by using paranasal sinus computed tomography (PNSCT). Methods: The study was designed retrospectively. PNSCT images in axial, coronal, and sagittal planes on both sides (right, R; left, L) were examined for sphenoid sinus, Vidian canal (VC), optic canal (OC), and carotid canal (CC) bilaterally. Results: The carotid canal did not show identification on the SS wall in females compared to males bilaterally (right, p= 0.002 and left, p= 0.002). The mean age was significantly higher in patients with a presellar type of sphenoid sinus (p=0.003). The mean age was significantly lower on the right side with a VC completely within the sphenoid sinus (p=0.005). The mean age of patients with an optic canal protrudation to the SS wall was significantly higher than patients with an optic canal indentation to the SS wall (p= 0.007). On the left side, cases with an optic canal protruding to the SS wall were older than cases with an optic canal indentation to the SS wall (p= 0.008). SS variations on the sagittal plane were significantly correlated with RVC, RCC, LVC, and LCC variations. Also, SS variations on the coronal plane were significantly related to types of LVC and RVC. Conclusions: Pneumatization of SS significantly affects the development of surrounding vital structures, especially with increasing age. [ABSTRACT FROM AUTHOR]

Objectives The authors examined the structural differences in the paranasal sinus region at sphenoid sinus in the pediatric population. Methods Paranasal sinus computed tomography (PNSCT) images of 86 pediatric subjects (30 males, 56 females) were included. In 13 to 15 years of age group (n =34) and ≥16 years of age group (n =52), sphenoid sinus pneumatization (SSP), optic canal and carotid canal classifications and dehiscence evaluation were performed. Results In both sexes, type 1 and type 2 SS pneumatization were observed more frequently on both the right and left sides. On the right side, type 2> type 1; on the left side type 1> type 2 optic canals were detected in both gender. Type 3 optic canals were detected in 8.8 to 14.7% of the 13 to 15 years of age group; and 11.5 to 17.3% of ≥16 years of age group. Type 4 optic canals were detected in 2.9% of the 13 to 15 years of age group and 1.9% of the ≥16 years of age group bilaterally. Optic canal dehiscence was detected in 26.5% of the 13 to 15 years of age group and 17.3% of the ≥16 years of age group. Type 1 and type 2 carotid canals are most common in children, the percentages for type 3 carotid canals were 1.8 to 3.6% in children. Conclusion In pneumatized SS, optic canal classifications got increased values which showed protrusion into the sphenoid sinus wall. Therefore, in children, the surgeons must be very careful for optic canal being nearer to the sphenoid sinus walls. [ABSTRACT FROM AUTHOR]

This article discusses a case study of a complication that occurred during the process of making customized earplugs and earmolds for hearing aids. The patient accidentally had silicone injected into their middle ear and Eustachian tube, which resulted in erosion of the carotid canal. The article emphasizes the importance of taking precautions and protecting the eardrum during the ear impression process to avoid serious complications. It also suggests that intra-aural 3D scanning of the external auditory canal may be an alternative solution in cases of tympanic perforation. [Extracted from the article]

الملخص: أهداف البحث: القناة السباتية عبارة عن ثقبة تقع في الجزء الصخري من العظم الصدغي. تعد المعرفة التفصيلية حول تشريح قاعدة الجمجمة مهمة حيث يتم إجراء العديد من العمليات الجراحية لمختلف الأورام الخبيثة وتمدد الأوعية الدموية. لذلك، فإن الهدف من هذه الدراسة هو جمع القياسات الشكلية المختلفة للقناة السباتية والتي ستساعد جراحي الأعصاب في الأساليب الجراحية المختلفة لتحديد مكان الجزء الثاني من الشريان السباتي الداخلي بسهولة. طرق البحث: تم إجراء دراسة بأثر رجعي وتحليل 500 مسح بالأشعة المقطعية على جانبي الجماجم. تم قياس العديد من المتغيرات المورفومترية المتعلقة بقناة الشريان السباتي. كما لوحظ شكل القناة السباتية. تم إجراء التحليل الإحصائي لجميع المعلمات. النتائج: كان متوسط أقطار القناة الأمامية الخلفية وعرض القناة السباتية 0.535 و 0.683 سم. وكان متوسط المسافة للقناة السباتية من الصماخ السمعي الخارجي والقوس الوجني والفك السفلي 2.27 و 3.28 و 2.34 سم على التوالي. كما كان متوسط مسافة القناة السباتية من خط الوسط لقاعدة الجمجمة في الجمجمة 2.97 سم. وكان متوسط الزاوية بين جذر الزيجوما والفتحة الخارجية لقناة الشريان السباتي والصماخ السمعي الخارجي 27.08 درجة. كانت الزاوية بين الصماخ السمعي الخارجي والفتحة الخارجية لقناة الشريان السباتي والقمة فوق الخشائية 26.74 درجة. كانت القناة السباتية دائرية في معظم الحالات (50.5٪). الاستنتاجات: ستساعد هذه القياسات جراحي الأعصاب على تحديد الأساليب الجراحية المختلفة لتحديد موقع الجزء الثاني بسهولة من الشريان السباتي الداخلي وستساعد أيضا في إجراء العمليات الجراحية في قاعدة الجمجمة. Abstract: Objectives: The carotid canal is a foramen located in the petrous part of the temporal bone. Detailed knowledge about the anatomy of the base of the skull is important, as many surgeries are done there for various malignancies and aneurysms. The aim of this study was to collect various morphometric measurements of the carotid canal to aid neurosurgeons with various surgical approaches to easily locate the second fragment of the internal carotid artery. Methods: A retrospective study was done, and 500 CT scans on both sides of the skull were analysed. Various morphometric parameters related to the carotid canal were measured. The shape of the carotid canal was also noted. Statistical analysis was done for all the parameters. Results: The mean anteroposterior diameter and width of the carotid canal was 0.535 and 0.683 cm, respectively. The mean distance of the carotid canal from the external acoustic meatus, zygomatic arch, and mandible was 2.27, 3.28, and 2.34 cm, respectively. The mean distance of the carotid canal from the midline of the base of the skull was 2.97 cm. The mean angle between the zygoma root, external aperture of the carotid canal, and external acoustic meatus was 27.08°. The mean angle between the external acoustic meatus, external aperture of the carotid canal, and supramastoid crest was 26.74°. The carotid canal was round in most cases (50.5%). Conclusion: These measurements will aid neurosurgeons to identify various surgical approaches to easily locate the second part of the internal carotid artery, and they can serve as a reference to guide surgeries at the base of the skull.

Background: Diameter of carotid canal is very much important because hypo-plastic of CC leads to multiple of neuro vascular complications, passing through these CC. Method: 45 male, 30 female adult non-pathological, dried crania were studied. The cranial Index was measured by winged calliper and diameter of CC by digital verniercalliper. The obtained values were correlated statistically. Results: Mean value of CI 64.09 (± 0.35) in male, 70.06 (± 0.98) in females crania Diameter of rt. Cc 0.76 (± 0.14) in male, 0.67 (± 0.09) in female crania, 0.74 (± 0.10) diameter of cc in males, 0.54(± 0.08) in cc of females crania and correlation coefficient of both male and female with CI and CCwere highly significant (p<0.001). Conclusion: Correlative coefficient study of CI and CC in both gender crania will be useful neuro-physician, neuro-surgeon,radiologist, medico-legal expert, anthropologist and anatomist because morpho-metric values of mesodermal derivatives are uncertain. [ABSTRACT FROM AUTHOR]

Purpose: There are only limited anatomical data on nerves, veins, and arteries in the temporal bone. More detailed anatomical data are required to improve planning of treatments targeting the temporal bone region. Herein, we performed a detailed analysis of the facial canal (FC) and the related carotid artery and vein. Methods: We examined the bony structure of the middle ear and FC, jugular foramen, and carotid canal in 30 Japanese elderly donor cadavers. Three-dimensional reconstruction of the canal structure was achieved using cone beam computed tomography, while macroscopic and histological analyses were also performed. Results: The FC form was classified as either straight (28%) or bent (72%). There were significant differences in the diameter of the FC and the distance between the internal jugular vein, other FC branches, and the FC. Principal component analysis (PCA) was performed for the FC using 29 factors. Two principal components significantly explained 30.9% (component 1, 18.6%; component 2, 12.3%) of the FC. Histological observation showed numerous ganglion cells and shrunken neurons in the geniculate ganglion of the facial nerve of elderly samples. Conclusion: FC diameter is an important contributor to the relationship between the FC and the jugular foramen. The FC and the internal jugular vein are located close to each other, which is useful information for the trans-canal surgery of the otology. Furthermore, the geniculate ganglion contains numerous ganglion cells and shrunken neurons, which may affect the FC structure during bone matrix remodeling with aging. [ABSTRACT FROM AUTHOR]

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This study was designed to observe the changes in the carotid canal over time by measuring the carotid canal diameter longitudinally in adult patients with moyamoya disease in whom disease stage progressed spontaneously. Of 70 adult patients with moyamoya disease, 10 adult patients on 15 sides with spontaneous progression of the disease stage during conservative follow-up were included in this study. Another 10 moyamoya cases on 15 sides were selected as the controls without disease progression. All patients were followed up for at least 60 months after the progression of disease stage was confirmed. In addition, 5 patients who underwent microvascular decompression were included as healthy controls. The carotid canal diameter was measured with bone window computed tomography (CT) and source images of time-of-flight magnetic resonance angiography at initial presentation, and then were serially monitored with the latter. There was a significant correlation between the values obtained from CT and magnetic resonance imaging (R2 = 0.992, P < 0.001). The carotid canal diameter in moyamoya disease at initial presentation was 4.29 ± 0.61 mm, being smaller than 5.20 ± 0.51 mm in healthy controls (P < 0.01). In response to disease progression, the carotid canal diameter started to decrease at 6 months after disease progression was confirmed, and reduced to about 85% of the original level during 60 months (P < 0.01). The phenomenon was not observed in patients without disease progression. The carotid canal diameter can decrease in response to disease progression even in adult moyamoya disease. "Negative" bone remodeling may play a key role in this unique phenomenon. [ABSTRACT FROM AUTHOR]

Background: Many reports have previously indicated the vast number of anatomical variations of the sphenoid sinuses, e.g. presence of the recesses. Notwithstanding, there are a few crucial neurovascular structures directly neighbouring with the sinuses. The following research aimed to evaluate frequency prevalence of the carotid canal's protrusion into the sphenoid sinuses in adult population.Materials and Methods: Computed tomography (CT) scans of the paranasal sinuses of 296 patients (147 females, 149 males) were analysed in this retrospective study. The patients did not present any pathology in the sinuses. Spiral CT scanner Siemens Somatom Sensation 16 was used in the standard procedure in the option Siemens CARE Dose 4D.Results: Protrusion of the carotid canal was found in the majority of the patients - 55.74%, more frequently in males (65.1% of the patients) than in females (46.26% of the patients). The said variant - regardless of gender - was noted more often bilaterally (41.55% of the cases: 29.93% females, 53.02% males) than unilaterally (14.19% of the cases: 16.33% females, 12.08% males). In the unilateral type (regardless of gender), the protrusion was more common for the left sphenoid sinus - 10.81% of the patients (12.24% females, 9.4% males) than for the right - 3.38% of the patients (4.08% females, 2.68% males).Conclusions: Complicated structure of the paranasal sinuses, derived from the high prevalence of their anatomical variations, may perplex routine surgical interventions. Henceforth, referral for a CT scan is imperative in order to abate the risks associated with an invasive procedure in the said region. [ABSTRACT FROM AUTHOR]

The bony carotid canal is a tube-like bone with a rough surface in contrast to smooth surfaces of the other parts of the temporal bone petrosal portion (petrosa): it takes an impression of the additional, out-sourcing product. No study had been conducted to evaluate a contribution of the adjacent sphenoid and pharyngotympanic tube (PTT) to the carotid canal. We examined sagittal and horizontal histological sections of hemi-heads from 37 human fetuses at 10 to 37 weeks. At 10 to 18 weeks, the future carotid canal was identified as a wide loose space between the cartilaginous cochlea and the ossified or cartilaginous sphenoid elements (ala temporalis and pterygoid). A linear mesenchymal condensation extending between the cochlear wall and ala temporalis suggested the future antero-inferior margin of the carotid canal. This delineation was more clearly identified in later stages. After 25 weeks, 1) the growing pterygoid pushed the PTT upward and, in turn, the PTT pushed the internal carotid artery (ICA) upward toward the petrosa: 2) a membranous ossification occurs in the dense mesenchymal tissue, the latter of which took an appearance of an anterior process of the petrosa; 3) the bony process of the petrosa involved the ICA inside or posteriorly. The bony carotid canal was made with membranous ossification in the dense mesenchymal tissue between the petrosa and sphenoid. The mother tissue was detached from the sphenoid by the PTT. The ossification of the septum between the ICA and tympanic cavity seemed to continue after birth. [ABSTRACT FROM AUTHOR]

In this retrospective study, we aimed to present important anatomical structures and distances for posterior fossa surgery by temporal multidetector computed tomography (MDCT). The temporal MDCT images of 317 adult patients (158 males and 159 females) were retrieved from the hospital's picture archiving and communication system (PACS). In the coronal temporal MDCT views, the cochlea-carotid canal and jugular bulb-mastoid bone outer surface were measured. In the axial MDCT views, the carotid canal-jugular bulb and carotid canal-posterior fossa distances were measured; the carotid canal and jugular bulb anterior-posterior (AP) and transverse dimensions were also measured. The bilateral cochlea-carotid canal, jugular bulb-mastoid bone outer surface, and right carotid canal-jugular bulb distances were significantly greater in the males than those in the females (p < 0.05). The carotid canal-posterior fossa distance was not different in both genders (p > 0.05). The carotid canal-jugular bulb and the carotid canal-posterior fossa distances were greater on the left side than those on the right side in both genders (p < 0.05). In males, the outer surface distance was greater on the left jugular bulb-mastoid bone than that on the right side of that bone (p < 0.05). The difference between the carotid canal AP dimensions was not significant between males and females (p > 0.05). However, the carotid canal transverse dimension, jugular bulb AP, and transverse dimensions were significantly greater in the males than those in the females, bilaterally (p < 0.05). In each gender separately, the carotid canal AP and transverse dimensions were greater on the left side and the jugular bulb AP and transverse dimensions were greater on the right side than those on the left side (p < 0.05). Positive correlations were found between the cochlea-carotid canal, the jugular bulb-mastoid bone outer surface, and the carotid canal-jugular bulb distances as well as between the jugular bulb-mastoid bone outer surface and the carotid canal-posterior fossa distances (p < 0.05). In older patients, the carotid canal-posterior fossa distances were shorter on the left side (p < 0.05). Vascular and neural localizations should be well understood in the operative area before applying the surgical approach in the posterior fossa. Computed tomography (CT) has a greater role in the evaluation of bone structures and vascular canals in this area. [ABSTRACT FROM AUTHOR]

Anomalies of the internal carotid artery associated with a violation of its embryonic development are classified as follows: agenesis, aplasia and hypoplasia. Agenesis is a rare vascular abnormality. The search and analyze the scientific articles data concerning the ICA embryogenesis and agenesis, absence of the internal carotid artery, to make comparative analysis of the adult skull with and without ICA. 104 human skulls served us as the research material.

OBJECTIVE: Anatomical information regarding the eustachian tube (ET) is limited; therefore, more detailed analytical data on ET structure is needed when planning surgical treatments involving the temporal bone. METHODS: We examined the bony structure of the middle ear and ET in 30 Japanese donor cadavers (71-97 years old at the time of death) both macroscopically and with cone-beam computed tomography. Each ET was reconstructed in 3 dimensions, and the structure and correlations of ET element measurements, identified via principal component analysis, were analyzed. RESULTS: Delineation between bony and cartilaginous zones appeared unclear, and the space between ET cartilage and the carotid canal was narrow. We observed stenosis of the ET bony canal in 43.3% of the specimens (n = 30). In 50% of the specimens, the position of the ET bony canal was depressed at the pharyngeal orifice of the auditory side of the tube, and the middle region was a roundish structure. The lateral and central regions of the bony canal were related to the ET bony canal structure. CONCLUSION: The close proximity of the ET bony canal to the carotid canal is an important anatomical and morphological finding. Pre-surgical 3D modeling of the middle ear structure, or at a minimum, of the central region of the middle ear canal, may provide useful information for planning procedures that involve the ET. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the success rate of eustachian tube (ET) occlusion in subtotal petrosectomy relative to the occlusive material used and to the varying protympanum anatomy, by means of standardized alignment of the cochlea‐carotid artery relation on computed tomography images. Patients and methods: All cases of subtotal petrosectomy carried out by the same surgeon at a tertiary care referral center were retrospectively evaluated. Only cases with available computed tomography prior to second stage cochlear or middle ear implantation were included. The occlusive material was either muscle tissue or oxidized regenerated cellulose in combination with bone wax. On 3D multiplanar image reconstruction, the varying topographic interrelation of the cochlea and the petrous carotid artery was measured and categorized into two groups: detachment or overlapping. Results: In 9 (31%) of the 29 included cases there was insufficient occlusion of the ET. In none of these cases was an infection of the fat filling in the obliterated cavity observed during the implantation procedure on second stage (average 10 months interval). The failure rate of both occlusion materials was almost the same (using muscle tissue, in 4 (33.3%) of 12 or oxidized regenerated cellulose, in 5 (29.4%) of 17 cases). It was also similar for both materials in each of the anatomic variation groups. Conclusions: An incomplete occlusion of the ET alone does not appear to lead to an infection of the obliterated cavity. Autologous muscle tissue and oxidized regenerated cellulose had similar rates of ET occlusion failure. The topographical variance of the protympanum appears to have no direct influence on the success of the ET occlusion. [ABSTRACT FROM AUTHOR]

Background: Surface landmarks of the temporal bone are related to various anatomical structures. The surgical exposure of the middle cranial fossa, transpetrosal and transmastoid approaches for skull base surgeries would require identification of various surface landmarks for approaching the structures. Aim and Objectives: To determine whether Henle's spine could be used as a reliable and multipurpose landmark for the important structures and foramen of the skull base during surgeries. Materials and Methods: This study was done on 170 dry human skulls. Two imaginary lines and a parapetrosal triangle was constructed which encompasses nearly all the main structures and foramina of the skull base. The distance from the Henle's spine to certain useful surgical landmarks on the skull base was measured and tabulated. Results: The measurements were analysed and compared by student't' test both the sides and found to be have slight variations in the measurements of right and left. Distance from Henle's spine to stylomastoid foramen and jugular foramen were found to high when compared to earlier studies other measurements showed only a slight deviations. Conclusion: Henle's spine when present (85%) can be used as a reliable anatomical landmark for approaching various foramina during skull base surgeries when other land mark fails.

The purpose of the research was to define the frequency prevalence of the incorporation of sphenoid sinuses' septum / septa in the carotid canal of the adult population. Materials and Methods: 296 computed tomography (CT) scans of the patients (147 females, 149 males), who did not present any pathology in the sphenoid sinuses, were evaluated in this retrospective analysis. Spiral CT scanner -- Siemens Somatom Sensation 16 -- was used to glean the medical images. Standard procedure applied in the option Siemens CARE Dose 4D. No contrast medium was administered. Multiplans reconstruction (MPR) tool was used in order to obtain frontal and sagittal planes from the transverse planes previously received. Results: Bilateral incorporation of the main septum (MS) in the carotid canal was not present in any of the patients, whereas unilateral incorporation was noticed in 21.96% of the patients (17.68% females, 26.17% males). On the right side it occurred in 11.82% of cases (10.88% females, 12.75% males), and on the left side in 10.14% of cases (6.8% females, 13.42% males). Bilateral incorporation of the additional septum (AS) was found in 8.45% of the patients (4.08% females, 12.75% males), whereas unilateral incorporation was noted in 28.37% of the patients. It was seen on the right side in 11.82% of cases (12.93% females, 10.74% males), and on the left side in 16.55% cases (15.65% females, 17.45% males). The most common variant was the incorporation of only one of the septa (either the MS or the AS) in the wall of the carotid canal unilaterally. Such situation took place in 30.07% of the patients (29.25% females, 30.87% males). Incorporation of two septa on the same side was noticed in 4.39% of cases (4.08% females, 4.7% males), and incorporation of three septa in 0.34% of cases (0.7% males). Conclusions: The anatomy of the paranasal sinuses is varied to a great extent, hence performing a CT scan is crucial before the scheduled surgery, as it may lessen the unforeseeable surgical complications, that may result from the high prevalence of variants in the sinuses. [ABSTRACT FROM AUTHOR]

The carotid canal is located in the petrous part of the temporal bone and transmits the internal carotid artery along with the venous and sympathetic nerve plexus. The shape, location and dimensions of the carotid canal are clinically very important especially in cases of skull base surgery. The aim of this study was to investigate the morphological and morphometric parameters of the external aperture of the carotid canal in Serbian population. The study included 24 dry adult skulls and 36 dry adult temporal bones. Diameters and distances of the external aperture of the carotid canal from various important landmarks of the skull base were measured. The shape of the external carotid canal aperture was also noted. Digital data were processed in the ImageJ software. The average length of the external aperture of the carotid canal in all investigated specimens (skulls and temporal bones) on the right and left sides was 7.31±1.01 mm and 7.71±1.06 mm, respectively. The average width of the external aperture of the carotid canal on the right side was 5.82±0.78 mm while on the left side was 6.20±1.04 mm. The frequency of different shapes of the external aperture of the carotid canal was as follows: round in 45 (53.57 %), oval in 25 (29.76 %), and the rarest was almond shape noted in 13 (15.47 %) cases. There were no statistically significant differences in all measured parameters between genders and body sides. The only statistical significance was found in females between right and left side in relation with length (AP diameter) of the external aperture of the carotid canal. The results of this study will be useful for neurosurgeons to improve different surgical approaches to the petrous part of the internal carotid artery and prevent its complications. [ABSTRACT FROM AUTHOR]

Background: There are neuro-ophthalmologic findings in patients with communicant hydrocephalus (CH).Purpose: To investigate the relationships of the optic canal and carotid canal classifications at sphenoid sinus and anterior clinoid process (ACP) pneumatization in patients with CH.Material and Methods: In this multicentric retrospective cross-sectional study, the cranial computed tomography (CT) images of 38 patients with CH (20 men, 18 women) and 40 controls (25 men, 15 women) were included. Optic and carotid canal classification at sphenoid sinus, ACP pneumatization, and sphenoid sinus septation were evaluated.Results: In the CH group, type 3 optic canal was detected in 21.1% of the patients and type 4 optic canal was detected in 2.6% of the patients on the left side which was significantly different from the control group (P<0.05). In the CH group, type 3 carotid canal was detected in 21.1% of the patients (left) and 18.4% of the patients (right). ACP pneumatization was present in 13.2% of the patients in the CH group bilaterally. There were positive correlations between optic canal classifications and ACP pneumatization (P<0.05). There were also positive correlations between the right and left carotid canal classifications and ACP pneumatization (P<0.05).Conclusion: To avoid complications, CT should be evaluated carefully in patients with CH before surgical interventions in sphenoid sinuses and surgeons should work carefully in the sphenoid sinus or adjacent structures. The protrusion possibility of the optic canal or carotid canal to the sphenoid sinus may be higher in pneumatized ACP patients. [ABSTRACT FROM AUTHOR]

Objectives: This retrospective computed tomography (CT) study was aimed to assess the growth dynamic of the external aperture of the carotid canal (EACC) in children aged between 1 and 20 years. Methods: Two hundred patients (sex 100 females/100 males, average age 10.50 ± 5.77 years) with good head CT image quality were included in this study. CT images of the patients were used to obtain data related to the location, shape and dimension of EACC. Results: EACC shapes were identified as oval shaped, round shaped, and tear-drop shaped in 58.3% (233 sides), 24% (96 sides) and 17.8% (71 sides), respectively. EACC length, disEACC–MSP (distance between EACC and midsagittal plane), and EACC width did not change from the prepubescence period; while, the disEACC–SC (distance between EACC and supramastoid crest) seemed to reach adult size in the postpubescence period. Linear functions for EACC length and width were calculated as: y = 5.453 + 0.091 × years, and y = 5.398 + 0.059 × years, respectively. Conclusion: The regression equations of the measured parameters representing the growth dynamic of EACC in children can be helpful to estimate its size, location and angulation, which suggest that the dimension and distances to certain anatomical landmarks seemed to reach adult size in different developmental periods. In this context, the findings of this study may seem to emphasize the importance of preoperative radiological evaluation on skull base, related to EACC, for multidisciplinary surgeon teams during childhood surgeries in terms of patients' positioning, and the selection of appropriate surgical approach. [ABSTRACT FROM AUTHOR]

The Henle's Spine (HS) or spina suprameatal or spina suprameatica or spinal meatus or meatal spine, can be defined as a small bony prominence, which is anterior to the supramastoid pit at bony external acoustic meatus in the posterosuperior margin . Localization of cranial structures using this anatomical landmark is of immense surgical importance to identify and avoid surgical morbidities. Considering the limited number of research articles describing its anatomy in South Indian skulls, present study was conducted to estimate the location and the difference between the right and left sides of the skull base foramen by using HS as surface landmark, which can act as a guide to various approaches of the skull base surgeries. Cross-sectional observational study. Thirty (60 sides) adult South Indian dry skulls with prominent HS were studied. Following distances on both right and left sides of the skulls were measured from tip of HS to foramen ovale, foramen spinosum, foramen lacerum, jugular foramen, carotid canal using digital calliper of 0.01 mm accuracy. Henle's spine can be used as a reliable surface landmark in skull base surgeries. Prior to surgeries, the possibility of side difference should be kept in mind involving jugular foramen. [ABSTRACT FROM AUTHOR]

The carotid canal is located near the apex of the petrous part of the temporal bone. It transmits the internal carotid artery, sympathetic nerve plexus, internal carotid venous plexus. It is considered to be an important anatomical landmark for neurosurgeons during surgeries. The study used about 30 South Indian dry human skulls of unknown sex. The morphometric variables were measured using a Vernier caliper. The collected data was statistically analyzed using SPSS version 20. From the obtained results, the majority of the shape of the carotid canal was 48.33% oval shaped, Majority of the right Carotid Canal ranged between 5.93 mm and 6.40 mm and the majority of the left Carotid Canal. ranged between 5.89 mm and 6.78 mm. The distance between majority of the C.C. and the margin of the foramen magnum, the occipital condyle and the apex of mastoid process were 26.97 mm, 19.70 mm and 28.67 mm respectively with no significant difference between the left and right carotid canals. This study concluded that the morphologic and morphometric data on the carotid canal showed no significant difference between the right and left sides of the skull. [ABSTRACT FROM AUTHOR]

To determine whether cranial metrics consistently differed between patients with moyamoya and age-, sex-, and race-matched controls. Patients diagnosed with moyamoya disease by cerebral angiogram were obtained from a prospectively collected database through the Department of Neurosurgery at the University of Kansas Medical Center. Control patients matched by decade of age, sex, and race were collected through a deidentified hospital database by International Classification of Diseases-9 and 10 codes for ischemic stroke to identify patients with computed tomography angiograms. Imaging studies for both groups were analyzed to obtain 6 skull metrics: maximum anterior to posterior distance, maximum biparietal distance, bregma to occiput distance, right carotid canal diameter (CCD), left CCD, and cephalic index. Forty-five patients were identified in each cohort. Measurements of mean anterior to posterior skull diameter, mean biparietal skull diameter, bregma to occiput distances, and calculated cephalic index did not demonstrate a statistically significant difference between patients with moyamoya and control patients. Right carotid canal mean diameter was 4.8 mm for the moyamoya group and 5.4 mm for the control group, with a significant raw mean difference of −0.61 mm (95% confidence interval, −0.95 to −0.27). Left CCD was 4.7 mm for the moyamoya group and 5.5 mm for the control group, resulting in a significant raw mean difference of −0.76 mm (95% confidence interval, −1.09 to −0.43). This study identified 2 skull parameters as statistically different in patients with moyamoya compared with a matched control group of patients with ischemic stroke: right CCD and left CCD. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study aimed to compare the right and left sides of the carotid foramen (CF) to determine its precise location according to certain anatomical landmarks. MATERIALS and METHODS: Twenty human dry skulls were included in the study. A digital caliper and a digital image analysis software were used to obtain direct anatomical numerical values. Then, the same parameters on dry skulls were assessed with computed tomography (CT). RESULTS: CF was found to be round shaped (62.5%), oval shaped (32.5%), and tear-drop shaped (5%). In all cases, the position of CF was seen as just postero-laterally of the foramen lacerum. According to the jugular foramen, CF was seen to be anterior in 85% and antero-medial in 15% of the cases. Regarding the morphometric values of the surface area, the length and width of CF were observed to be 37.86±11.24 mm2, 8.02±1.09 mm, and 6.86±0.90 mm at direct anatomical measurements and 39.69±10.07 mm2, 7.89±1.14 mm, and 6.41±0.90 mm at CT, respectively. The angles between the supramastoid crest-CF-zygoma root and the supramastoid crest-CF-mastoid process were determined as 37.11±6.87° and 42.22±6.40° at direct anatomical measurements and 36.59±4.94° and 43.71±4.55° at CT, respectively. CONCLUSION: A significant difference in sides was not observed in relation with the numerical data of CF obtained from CT or from direct anatomical measurements of dry skulls. Moreover, a significant difference was not found between radiological and direct anatomical measurements. Therefore, precise radiological assessment of this region by an experienced neuroradiologist may be assumed as a fundamental need for successful surgeries of the skull base, in addition to thorough anatomical knowledge of neurootologists and neurosurgeons. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the relationship between sphenoid sinus, carotid canal, and optic canal on paranasal sinus computed tomography (PNSCT). This study was performed retrospectively. PNSCT images of 300 adult subjects (159 male, 141 female). Sphenoid sinus (pneumatisation, dominancy, septation, inter-sinus septa deviation), anterior clinoid process pneumatisation, Onodi cell, carotid and optic canals (width, dehiscence, classification) were measured. In males, type 3 pneumatised sphenoid sinus (in both sides) and in females type 2 pneumatised sphenoid sinus (right side) and type 3 pneumatised sphenoid sinus (left side) were detected more. Anterior clinoid pneumatisation was present 47.2% in males and 39.7% in females. In male group, more septation (i.e. 22.6%, ≥ 3 septa) in sphenoid sinus were detected. Onodi cell was present 26.6 and 19.1% in males and females, respectively. Carotid canal protrudation to the sphenoid sinus wall was present 23.9–32.1% in males and 35.5–36.2% in females. Dehiscence in carotid canal was detected more in females (34%) compared to males (22%). Optic canal protrudation was 33.3 and 30.5% in males and females. Type 4 optic canal was detected more in both gender. Optic canal dehiscence was detected 11.3 and 9.9% in males and females. Carotid and optic canal diameters were higher in males. In pneumatised sphenoid sinuses and in females, type 3 carotid canal (Protrudation to SS wall) (bilaterally) and type 1 optic canal type (No indentation) (ipsilateral side) were detected more. In elderly patients, carotid and optic canal width increased. When carotid canal protrudation was detected, there was no indentation in optic canals In pneumatised SS, carotid canal protrudation was observed with a greater risk in surgery. However, type 1 (non indentation) optic canal was present in highly pneumatised SS with lower risk for the surgery. In women, the risk of carotid canal protruding (about 1/3) is greater than that of males, and carotid canal dehiscence rates are also higher in females. Therefore, physicians should be very careful during the preparatory stages of the sphenoid sinus surgery. Otherwise, it may not be possible to prevent lethal carotid artery bleeds. [ABSTRACT FROM AUTHOR]

Objectives: In humans, neuronal processes related to brain development elevate the metabolic rate of brain tissue relative to the body during early childhood. This phenomenon has been hypothesized to contribute to slow somatic growth in preadolescent Homo sapiens. The uncoupling of the brain's metabolic rate from brain size during development complicates the study of the evolutionary emergence of these traits in the fossil record. Here, we extend a method previously developed to predict interspecific differences in cerebral blood flow (a correlate of cerebral glucose use) to predict ontogenetic changes in human brain metabolism. Materials and methods: Radii of the carotid foramen from an ontogenetic series of modern human crania were used to predict blood flow rates through the internal carotid arteries (ICA), which were compared to empirically measured ICA flow and brain metabolism values. Results: Predictions of both absolute ICA blood flow rates and perfusion (ICA blood flow rates relative to brain size) generally match measured values in infancy and childhood. Maximum predicted ICA blood flow rates and perfusion were found to occur between ages 5 and 8, which roughly correspond to the age of maximum measured ICA blood flow rate and absolute and brain mass‐specific rate of whole brain glucose uptake. Discussion: These findings suggest that, during human growth and development, the size of the carotid foramen corresponds well to blood flow requirements through the ICA, and the method tested here may provide new opportunities for studying developmental changes in brain metabolism using osteological samples, including fossil hominins. [ABSTRACT FROM AUTHOR]

Background and Objective The carotid canal (CC) is a bent passage in the petrous temporal bone from where the internal carotid artery (ICA) goes inside the skull. The shape, location and measurements of the CC are clinically very important in cases of skull base surgery, since the ICAhas to be identified and isolated throughout its petrous course. Therefore, the present study was performed tomeasure and locate the CC from various important anatomical landmarks. Materials and Method The present study was conducted on 68 dry skulls of unknown gender. Various measurements and distances of the CC from various important landmarks were taken. The shape of the CC was also noted. Measurements were taken with the help of a screw-adjusted compass and of digital Vernier calipers. From the above measurements, mean and standard deviation (mean ± SD), median, range, and mode were calculated. Data analysis was done with IBM SPSS Statistics for Windows, Version 19.0 (IBM Corp, Armonk, NY, USA). Results Themean length of the CC on the right and left sideswas 7.76 and 7.89 mm, respectively. The mean breadth of the CC on the right and left sides was 5.81 and 6.32 mm, respectively. Themost common shape of the CC was round both on the right and left sides in 49.20% and in 53.12% of the cases. Conclusion The results of the present study will be useful in the performance of neurosurgical procedures, thereby preventing unpleasant complications. [ABSTRACT FROM AUTHOR]

Foramen Spinosum (FS) is one of the chief foramens in the infratemporal surface of greater wing of the sphenoid which is situated just posterior and lateral to foramen ovale. It is a significant landmark in cases of damage to the base of skull particularly in the middle cranial fossa and infratemporal fossa. It is usually needed as a landmark in neurosurgery because of its adjacent relations with other cranial foramina. So, this study was undertaken to determine the precise range of dimensions, the variations, asymmetry, and dissimilarity of the size seen in the foramen spinosum in the South Indian population. Sixty eight dry skulls of unknown sex were used for the study. Various measurements and distance from various surgical landmarks were taken to assess the position of foramen spinosum on both sides of skull. We also calculated the area of foramen spinosum. Various shapes of foramen spinosum were also noted, i.e. round, oval, pin hole or irregular. Statistical Analysis was done for the all the measurements using spss software. The mean anteroposterior diameter of foramen spinosum was 2.955±1.132 mm, 3.226±0.813 mm on the right and left sides. The mean transverse diameter of foramen spinosum came out to be 2.169±0.804 mm on right side and 2.274±9.174 mm on left side. There was no statistical significance in any parameter measured on the right and left side. This study will be helpful for neurosurgeons while doing surgery in the middle cranial fossa.

Carotid sympathetic plexus schwannomas are rare, and only 3 cases have been reported to the best of our knowledge. We report the fourth and fifth cases and define its origin on the basis of the exact division of the plexus from which the tumor arises. The surgical approach and technique in each variety and the postoperative outcome are also described. The relationship of partial Horner syndrome with the sympathetic plexus schwannoma of the internal carotid artery is discussed in detail. Highlights • Carotid sympathetic plexus (CSP) schwannomas are rare; only 3 cases are reported in the literature. • Two unique cases involving the petrous ICA are described along with surgical technique. • A new classification for schwannomas along the carotid plexus is described, and the surgical approach is discussed. • The use of angiographic study in these tumors has been emphasized. [ABSTRACT FROM AUTHOR]

To assess the safety of Transtympanic balloon dilatation of the cartilaginous proximal Eustachian tube under endoscopic guidance as it relates to the integrity of the carotid canal in cadaver model. Endoscopic guided Transtympanic dilatations of the cartilaginous proximal end of the Eustachian tube were performed in 15 ears of 8 fresh frozen cadaver heads. CT scans were done before and after dilatation. Images were reviewed by two otologists and one radiologist. Balloon catheter placement and dilatation of the proximal Eustachian tube was feasible in all specimens. Endoscopic examination post dilatation showed a consistent increase in the aperture of the proximal cartilaginous tube in all ears. Review of CT images after dilatation showed no evidence of trauma to the carotid canal in all ears instrumented. Endoscopically guided Transtympanic dilatation of the proximal Eustachian tube is not associated with damage to the carotid canal in cadaver model.Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

The aim of this study was to reveal the clinical importance of measurements taken from the pharyngeal tubercle (PT) to various anatomical structures around the extracranial clivus. Twenty-six adult dry Anatolian skulls were examined. The extracranial clivus and PT were used as landmarks from which various distances were measured using a digital caliper accurate to 0.01 mm. The following mean distances from the PT were observed; foramen lacerum (FL) (L: 17.15 mm, R: 17.4 mm) ; medial external margin of the carotid canal (CC) (L: 26.7 mm, R: 27.5 mm); anterior tip of occipital condyle (OC) (L: 16.4 mm, R: 16.3 mm); anterior margin of foramen magnum (FM) (10.8 mm); foramen ovale (FO) (L: 25.9 mm, R: 29.1); medial margin of the jugular fossa (JF) (L: 25.4 mm, R: 25.7 mm); medial external margin of the hypoglossal canal (HC) (L: 20.0 mm, R: 19.9 mm). Mean bilateral distances were: LFO-RFO: 45.34 mm; LFL-RFL: 20.1 mm; LCC-RCC: 52.1 mm; LOC-ROC: 17.6 mm; LJF-RJF: 45.2 mm; LHC-RHC: 33.5 mm. The following mean distances were observed from the FM: FM-OC (L: 8.3 mm, R: 9.3 mm); FM-HC (L: 17.8 mm, R: 17.4 mm). Also the mean distance of OC-HC were observed (L: 11.7 mm, R: 11.4 mm). Present measurements suggest that the PT can be used as an anatomical landmark during surgery involving clival pathology. However, the anatomy and variations of the extracranial clivus and surrounding structures must be taken into consideration. [ABSTRACT FROM AUTHOR]

Foramen Spinosum (FS) is one of the chief foramens in the infratemporal surface of greater wing of the sphenoid which is situated just posterior and lateral to foramen ovale. It is a significant landmark in cases of damage to the base of skull particularly in the middle cranial fossa and infratemporal fossa. It is usually needed as a landmark in neurosurgery because of its adjacent relations with other cranial foramina. So, this study was undertaken to determine the precise range of dimensions, the variations, asymmetry, and dissimilarity of the size seen in the foramen spinosum in the South Indian population. Sixty eight dry skulls of unknown sex were used for the study. Various measurements and distance from various surgical landmarks were taken to assess the position of foramen spinosum on both sides of skull. We also calculated the area of foramen spinosum. Various shapes of foramen spinosum were also noted, i.e. round, oval, pin hole or irregular. Statistical Analysis was done for the all the measurements using spss software. The mean anteroposterior diameter of foramen spinosum was 2.955±1.132 mm, 3.226±0.813 mm on the right and left sides. The mean transverse diameter of fo ramen spinosum came out to be 2.169±0.804 mm on right side and 2.274±9.174 mm on left side. There was no statistical significance in any parameter measured on the right and left side. This study will be helpful for neurosurgeons while doing surgery in the middle cranial fossa. [ABSTRACT FROM AUTHOR]

Introduction: The morphology of the skull base can be altered in craniosynostoses. The objective of this study is to evaluate the reduced intercarotid artery distance in the lacerum segment in patients with syndromic and isolated brachycephaly.Materials and Methods: The distances between the inner walls of the carotid canal at the lacerum segment were measured on high-resolution CT scans in children with Crouzon (25), Pfeiffer (21), Apert (26), Saethre-Chotzen (7) syndromes, isolated bicoronal synostosis (9), and compared to an age-matched control group (30).Results: A significantly smaller mean distance between carotid canal walls was observed in Crouzon (11.1 ± 4.9 mm), Pfeiffer (9.6 ± 5.1 mm), Apert (12.3 ± 4.3 mm), Saethre-Chotzen (14.8 ± 3.0 mm) syndromes, and isolated bicoronal synostosis (14.9 ± 3.7 mm) as compared to the control group (19.7 ± 2.4 mm, P < 0.001, P < 0.001, P < 0.001, P = 0.005, and P = 0.002, respectively). There was no statistically significant difference in intercarotid canal distance among the Apert, Saethre-Chotzen and isolated bicoronal synostosis groups. Overall, the brachycephalic group showed reduced intercarotid canal distance comparing to controls (P < 0.001).Discussion and Conclusions: There is significant reduction of the distance between carotid canals in brachycephalic patients. This distance is more significantly altered in FGFR-related brachycephaly syndromes (especially Crouzon and Pfeiffer syndromes), than Saethre-Chotzen syndrome (TWIST1 mutation) and isolated non-syndromic bicoronal synostosis. This study highlights the importance of FGFRs in shaping the skull base. Altered vascular course of the internal carotid arteries can have important implications in planning skull base surgery in brachycephalic patients. [ABSTRACT FROM AUTHOR]

Background: Surface landmarks of the temporal bone are related to various anatomical structures. The surgical exposure of the middle cranial fossa, transpetrosal and transmastoid approaches for skull base surgeries would require identification of various surface landmarks for approaching the structures. Aim and Objectives: To determine whether Henle's spine could be used as a reliable and multipurpose landmark for the important structures and foramen of the skull base during surgeries. Materials and Methods: This study was done on 170 dry human skulls. Two imaginary lines and a parapetrosal triangle was constructed which encompasses nearly all the main structures and foramina of the skull base. The distance from the Henle's spine to certain useful surgical landmarks on the skull base was measured and tabulated. Results: The measurements were analysed and compared by student't' test both the sides and found to be have slight variations in the measurements of right and left. Distance from Henle's spine to stylomastoid foramen and jugular foramen were found to high when compared to earlier studies other measurements showed only a slight deviations. Conclusion: Henle's spine when present (85%) can be used as a reliable anatomical landmark for approaching various foramina during skull base surgeries when other land mark fails. [ABSTRACT FROM AUTHOR]

Normal vascular variants often have clinical/surgical significance and can be misinterpreted for pathology. We report a case ascending pharyngeal artery arising from a hypoplastic internal carotid artery. We provide clues to differentiate between dysgenesis and disease/thrombosis of the internal carotid artery.

Background: The carotid canal (CC) located in the petrous temporal bone transmits the internal carotid artery, internal carotid venous plexus and sympathetic nerve plexus from the neck into the cranial cavity. It is an accessible passage into the cranial cavity and is considered an important anatomical landmark for neurosurgeons. The aim of this study was to investigate the topographical, morphometric and morphological parameters of the CC.Materials and Methods: An examination of the CC and related adjacent structures in 81 dry skull specimens was performed. Distribution of sample by sex was 34 females and 47 males, and by race 77 African and 4 Caucasian. The mean age was 50 years (range: 14-100 years).Results: The external opening of the CC was found to be round-shaped, oval-shaped and tear-drop-shaped in 28.4%, 49.4% and 22.2% of the specimens, respectively. (1) Mean diameters [mm]: (a) medio-lateral 7.52 mm and (b) antero-posterior 5.41mm. Statistically significant difference in the vertical diameter was recorded in the race groups and laterality of the samples. (2) Mean distances [mm] between: (a) medial margins of external opening of CC was 50.03 mm, (b) lateral margins of external opening of CC was 62.73 mm and (c) external openings of CC and foramen lacerum was 15.6 mm. There was a statistically significant correlation between race and location of the opening of external CC in relation to foramen lacerum (viz. postero-lateral, lateral and diagonal, and lateral).Conclusions: The present study corroborated previous reports on the CC; however, the tear-drop shaped external CC opening was a unique finding. The knowledge of the reference measurements pertaining to the CC and its relationship to adjacent structures may postulate a suitable surgical "safe-zone" range within the CC area. [ABSTRACT FROM AUTHOR]

Inflammation and angiogenesis play major roles in carotid plaque vulnerability. The purpose of this study was to determine whether gray-scale features of carotid plaques are associated with histologic markers for inflammation. Thirty-eight individuals completed a dedicated research carotid ultrasound exam before carotid endarterectomy. Gray-scale analysis was performed on plaque images to measure plaque echogenicity (gray-scale median [GSM] pixel brightness), plaque area, presence of discrete white areas (DWAs) and the percent of black area near the lumen on any one component of the plaque. Plaques with higher ultrasound GSM had greater percent calcification (p = 0.013) on histopathology. Presence of an ultrasound DWA was associated with more plaque hemosiderin (p = 0.0005) and inflammation (p = 0.019) on histopathology examination. The percent of plaque black area in any one component was associated with a higher score for macroscopic ulceration (p = 0.028). Ultrasound plaque characteristics (GSM, DWAs and black areas) represent histopathologic markers associated with plaque vulnerability. ClinicalTrials.gov identifier: NCT02476396. [ABSTRACT FROM AUTHOR]