Unreported variant foramen of the frontal bone: the latero-orbital foramen.

Variant foramina of the skull can lead to misdiagnosis on medical imaging and potentially, intraoperative complications if not appreciated. Here, we report an unusual foramen found superior to the frontozygomatic suture. The foramen was located on the left side at the superolateral rim of the orbit, 2.36 cm inferolateral to the supraorbital foramen. It was positioned 2.5 mm superior to the frontozygomatic suture. The foramen had a length of 3.1 mm and a width of 1.3 mm. The internal opening of the foramen was located 1.45 cm superolateral to the zygomaticotemporal foramen. We suggest that this foramen is a pathway for either a branch of the zygomatic nerve or lacrimal nerve and/or their vascular bundles. Although the prevalence of such a finding cannot be confirmed, such a case is of archival value as a comparison for future similar cases.

Crista Galli Morphometry and Morphology: An Anatomical, Radiological, and Machine Learning Application Study / Crista Galli Morfometría y Morfología: Un Estudio de Aplicación Anatómica, Radiológica y de Aprendizaje Automático

SUMMARY: The study purposed to examine the morphometry and morphology of crista galli in cone beam computed tomography (CBCT) and apply a new analysis, supervised Machine Learning techniques to find the answers to research questions "Can sex be determined with crista galli morphometric measurements?" or "How effective are the crista galli morphometric measurements in determining sex?". Crista galli dimensions including anteroposterior, superoinferior, and laterolateral were measured and carried out on 200 healthy adult subjects (98 females; 102 males) aged between 18-79 years. Also, crista galli was classified with two methods called morphological types and Keros classification. In this study, the Chi-square test, Student's t-test, and Oneway ANOVA were performed. Additionally, Machine Learning techniques were applied. The means of the CGH, CGW, and CGL were found as 14.96 mm; 3.96 mm, and 12.76 mm in males, respectively. The same values were as 13.54 mm; 3.51 mm and 11.59±1.61 mm in females, respectively. The CG morphometric measurements of males were higher than those of females. There was a significant difference between sexes in terms of morphological classification type. Also, when the sex assignment of JRip was analyzed, out of 102 male instances 62 of them were correctly predicted, and for 98 female instances, 70 of them were correctly predicted according to their CG measurements. The JRip found the following classification rule for the given dataset: "if CGH<=14.4 then sex is female, otherwise sex is male". The accuracy of this rule is not high, but it gives an idea about the relationship between CG measurements and sex. Although the issue that CG morphometric measurements can be used in sex determination is still controversial, it was concluded in the analysis that CG morphometric measurements can be used in sex determination. Also, Machine Learning Techniques give an idea about the relationship between CG measurements and sex.

En el estudio se propuso examinar la morfometría y la morfología de la crista galli del hueso etmoides usando tomografía computarizada de haz cónico (CBCT) y aplicar un nuevo análisis, técnicas de aprendizaje automático supervisado para encontrar las respuestas a las preguntas de investigación "¿Se puede determinar el sexo con mediciones morfométricas de la crista galli?" o "¿Qué tan efectivas son las medidas morfométricas de la crista galli para determinar el sexo?". Las dimensiones de la crista galli, incluidas los diámetros anteroposterior, superoinferior y laterolateral, se midieron y realizaron en 200 sujetos adultos sanos (98 mujeres; 102 hombres) con edades comprendidas entre los 18 y los 79 años. La crista galli se clasificó con dos métodos llamados tipos morfológicos y clasificación de Keros. En este estudio, se realizaron la prueba de Chicuadrado, la prueba t de Student y ANOVA de una vía. Adicionalmente, se aplicaron técnicas de Machine Learning. Las medias de CGH, CGW y CGL se encontraron en 14,96 mm; 3,96 mm y 12,76 mm en hombres, respectivamente. Los mismos valores fueron 13,54 mm; 3,51 mm y 11,59 ± 1,61 mm en mujeres, respectivamente. Las medidas morfométricas del CG de los hombress fueron más altas que las de las mujeres. Hubo una diferencia significativa entre sexos en cuanto al tipo de clasificación morfológica. Además, cuando se analizó la asignación de sexo de JRip, de 102 instancias masculinas, 62 de ellas se predijeron correctamente, y de 98 instancias femeninas, 70 de ellas se predijeron correctamente de acuerdo con las mediciones de CG. El JRip encontró la siguiente regla de clasificación para el conjunto de datos dado: "si CGH<=14.4, por tanto el sexo es femenino, de lo contrario, el sexo es masculino". La precisión de esta regla no es alta, pero da una idea de la relación entre las medidas del CG y el sexo. Aunque la pregunta si las medidas morfométricas CG se pueden usar en la determinación del sexo sigue aún siendo controvertida. Se concluyó en el análisis que las medidas morfométricas CG se pueden usar en la determinación del sexo. Además, las técnicas de aprendizaje automático dan una idea de la relación entre las medidas de CG y el sexo.

Endoscopic Approach for Resection of Frontal Forehead Osteoma: Technical Case Report Instruction.

Forehead osteomas are benign bone tumors. They are frequently associated with exophytic growth in the outer table of the skull, causing cosmetic disfigurement of the face.1-9 The objective of this study was to present the efficacy and feasibility of the endoscopic treatment of forehead osteomas by presenting a case report with details of the surgical technique. A 40-year-old female patient presented with aesthetic complains of a progressing bulge in the forehead. A computed tomography scan with 3-dimensional reconstruction showed bone lesions on the right side of the forehead. The patient underwent surgery under general anesthesia with no noticeable incision, which was planned 2 cm behind the hairline in the midline because the osteoma was close to the midline plane on the forehead (Video 1). A retractor coupled with a 4-mm channel for endoscopy and a 30-degree optic was used to dissect, elevate the pericranium, and locate the 2 bone lesions in the forehead. The lesions were removed using a chisel, endoscopic facelifting raspatory, and a 3-mm burr drill. The tumors were resected completely, resulting in good cosmetic outcomes. The endoscopic approach for treating forehead osteomas is less invasive and facilitates complete removal of tumors, which results in good cosmetic outcomes. Neurosurgeons should consider and add this feasible approach to enhance their surgical armamentarium.

Intraosseous malignant peripheral nerve sheath tumor at the frontal bone in a child: a rare cause of proptosis.

We report a nine-year-old male having malignant peripheral nerve sheath tumor (MPNST) of the frontal bone, represented with a twelve-month history of ptosis and proptosis in his right eye and enlarged rapidly in the last three months. Except for slight numbness at his one-third of the right forehead, he had no neurological deficit. The patient's both eyes were having normal eye movements, and he had no visual acuity or field loss. After surgery, we observed the patient with no recurrence for 4 years.

Statistical classification methods for estimating sex based on five skull traits: A nonmetric assessment using 3D CT models.

Five cranial nonmetric traits for sex estimation for sex estimation are classified by score according to geometry. The population of origin is one of the factors influencing cranial nonmetric traits. Moreover, among the five cranial traits, the robust traits for estimating sex varied across population. The aim of this study is to suggest the most useful method for sex estimation and demonstrate the need of a suitable method for each population. One-hundred thirty-five three-dimensional skull images from 21st century Korean autopsy cadavers were evaluated using the ordinal scoring system of five cranial nonmetric traits as outlined in Buikstra & Ubelaker (1994). All scores of each trait were analyzed by linear discriminant and decision tree analyses for sex estimation. The frequency of each trait was analyzed and compared to populations from other studies. The accuracy for both sexes was 88.1% by discriminant analysis and 90.4% by decision tree. The traits with the highest accuracy were the glabella and mastoid process in both discriminant analysis and decision tree. Sex estimation in modern Korean cadavers using the cranial nonmetric method was shown to be highly accurate by both discriminant analysis and decision tree. When comparing the pattern of frequency scores in this study with those of other populations, the pattern of trait scores for estimating sex was different for each population, even among populations in the same Asian region, which suggests the need for methods suited for specific populations.

Orbital Schwannoma With Frontal Bone Lysis.

Orbital schwannoma is an exceptionally rare cause of ptosis. Diagnosis may be elusive given its slow rate of growth and its various presentations depending on localization. Herein, we report the case of a 50-year-old male who presented to our clinic with a complaint of unilateral, recurrent ptosis of the left eye. He underwent levator palpebrae resection, which was unsuccessful at improving his ptosis. He later represented with acute-onset diplopia for which magnetic resonance imaging was obtained. Magnetic resonance imaging showed a lesion in the superior orbit with secondary bony dehiscence of the orbital roof. Through a vertical lid-split incision, the lesion was removed, and the frontal lobe was observed protruding through the defect in the orbital roof. This case highlights the importance of diagnostic skepticism in the face of recurrent ptosis and emphasizes the utility of the vertical lid-split approach for anterior lesions of the superior orbit.

Frontal Bone Osteomyelitis in Adult.

Frontal bone osteomyelitis is a rare clinical disease which occurs as a result of frontal sinusitis, penetrating injury on head, post-operative complication after sinus surgery and hematogenous spread from distant site. Early diagnosis, appropriate surgical debridement and antibiotic are keys to prevent from life threatening intracranial complications. We report a 63 years old male patient with osteomyelitis of outer cortex of frontal bone. The wound was thoroughly debrided after computer tomography scan showed an osteolytic lesion on outer table of fontal bone and antibiotic was continued for 2 months until inflammatory markers become normal. Keywords: Frontal bone; Intracranial complications; osteomyelitis; pott's puffy tumour.

Late Deformity Following Fronto-Orbital Reconstructive Surgery for Metopic Synostosis: The Role of Temporalis Muscle.

ABSTRACT: Theories for late-developing deformity (LDD) following fronto-orbital reconstructive surgery (FOR) for metopic synostosis (MS) must explain both its delayed onset and its physical characteristics. This study examined whether FOR-related interference with the normal childhood expansion of temporalis is responsible for its soft tissue component.Three-dimensional reformats of preoperative and postoperative computed tomography scans of MS patients were reviewed. Measurements of vertical and horizontal reach of temporalis against those of the underlying skull (to allow for normal skull growth) were compared with normal subjects. The thickness of temporalis and the development of the temporal crests were also assessed.Mean age at FOR was 17.1 months; interval between surgery and first report of LDD 4.7 years; mean age at computed tomography scan for post-FOR LDD patients 8.8 years. There was a significant difference between vertical and horizontal reach of temporalis in pre-FOR MS patients compared to normal subjects ( P < 0.0017 and P < 0.05, respectively). The vertical age-related reach of temporalis in post-FOR patients after allowing for underlying skull growth was significantly reduced ( P = 0.0045) compared to normal subjects but not its horizontal reach ( P = 0.25). Temporal crests in LDD patients were absent or aberrantly formed while muscle thickness was similar to normal subjects at the 2 levels measured.This study supports the theory that failure of the normal childhood expansion of temporalis is responsible for the soft tissue element of LDD, accounting for both its delayed onset and physical characteristics. Aberrant temporal crest development suggests FOR-related damage as the probable cause.

Quantitative Morphologic Analysis of Cranial Vault in Twist1+/- Mice: Implications in Craniosynostosis.

BACKGROUND: The haploinsufficiency in the TWIST1 gene encoding a basic helix-loop-helix transcription factor is a cause of one of the craniosynostosis syndromes, Saethre-Chotzen syndrome. Patients with craniosynostosis usually require operative release of affected sutures, which makes it difficult to observe the long-term consequence of suture fusion on craniofacial growth. METHODS: In this study, we performed quantitative analysis of morphologic changes of the skull in Twist1 heterozygously-deleted mice (Twist1+/-) with micro-computed tomographic images. RESULTS: In Twist1+/- mice, fusion of the coronal suture began before postnatal day 14 and progressed until postnatal day 56, during which morphologic changes occurred. The growth of the skull was not achieved by a constant increase in the measured distances in wild type mice; some distances in the top-basal axis were decreased during the observation period. In the Twist1+/- mouse, growth in the top-basal axis was accelerated and that of the frontal cranium was reduced. In the unicoronal suture fusion mouse, the length of the zygomatic arch of affected side was shorter in the Twist1+/- mouse. In one postnatal day 56 Twist1+/- mouse with bilateral coronal suture fusion, asymmetric zygomatic arch length was identified. CONCLUSION: The authors'results suggest that measuring the length of the left and right zygomatic arches may be useful for early diagnosis of coronal suture fusion and for estimation of the timing of synostosis, and that more detailed study on the growth pattern of the normal and the synostosed skull could provide prediction of the risk of resynostosis. CLINICAL RELEVANCE STATEMENT: The data from this study can be useful to better understand the cranial growth pattern in patients with craniosynostosis.

Studies of Supraorbital Notch and Foramen Using 3-Dimensional Facial Bone CT Scans.

BACKGROUND: The supraorbital foramen or notch is located at the superior orbital rim. Previous studies have reported anatomical variations in these structures. However, the results varied depending on races and the measurement method used. OBJECTIVE: The purpose of this study is to identify the morphological features of supraorbital foramen or notch based on locational relationship using images of 3-dimensional (3D) facial bone CT scans. STUDY DESIGN: Retrospective study. SETTING: University hospital emergency department.  METHODS: Identification and analysis of patients who have undergone facial bone 3D CT were performed using Clinical Data Warehouse v 2.5 (CDW, Planit Healthcare, Seoul, Korea). The search word that we used with the CDW for analysis was "facial bone 3D CT".First, the region of the supraorbital rim was examined to clarify whether or not the supraorbital foramen or notch was present. Second, the diameter of the supraorbital foramen or notch was measured. Lastly, the distance from midpoint (nasion) to the supraorbital notch or foramen was measured. RESULTS: The supraorbital notch was found more frequently than the supraorbital foramen. Among supraorbital double types, the coexistence of notch and foramen was found more frequently than the coexistence of notch and notch or foramen and foramen. The diameter of supraorbital notch was wider than the supraorbital foramen, which was located more laterally from the nasion than the supraorbital notch. LIMITATION: The actual size of the facial image or the skull size of the patient was not considered, which might affect the distance of supraorbital notch or foramen from the midline. CONCLUSION: Supraorbital notch was more frequently found than the supraorbital foramen. The supraorbital notch had a wider diameter and was more centrally located than the supraorbital foramen.

Pott's Puffy Tumor.

Pott's puffy tumor is a potential complication of acute frontal sinusitis, characterized by subperiosteal abscess and osteomyelitis of the frontal bone. It can be managed with a combination of open and endoscopic sinus surgery and intravenous antibiotic therapy. In the current report, a 15-year-old male presented with a classic case of Pott's puffy tumor which was managed with bilateral ethmoidectomies, frontal sinusotomies, and frontal sinus trephination, resulting in discharge on intravenous antibiotic therapy and subsequent complete resolution of symptoms.

Diagnosis and Management of Suture-Related Concerns of the Infant Skull.

The cranial fontanelles and sutures have several benign variations, including most cases of "early" or "late" closure of the anterior fontanelle, bathrocephaly, overriding sutures, and benign metopic ridging. However, recognizing true craniosynostosis and referring the patient to a craniofacial specialist in a timely fashion are imperative, as minimally invasive options can be offered to most patients younger than 6 months of age. Gaining comfort with the physical examination of an infant with an abnormal head shape is best achieved through experience and pattern recognition and will frequently facilitate an accurate diagnosis without the need for ionizing radiation.

Computer-Aided Design and Manufacturing versus Conventional Surgical Planning for Head and Neck Reconstruction: A Systematic Review and Meta-Analysis.

BACKGROUND: Virtual surgical planning and computer-aided design/computer-aided manufacturing (CAD/CAM) for complex head and neck reconstruction has a number of cited advantages over conventional surgical planning, such as increased operative efficiency, fewer complications, improved osseous flap union, immediate osseointegrated dental implant placement, and superior functional and aesthetic outcomes. The authors performed a systematic review and meta-analysis of the available evidence on CAD/CAM maxillofacial reconstruction with the primary purpose of determining which approach is more efficacious. METHODS: In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a PubMed and Embase database search was performed to identify English-language, human-subject studies of CAD/CAM-assisted head and neck reconstruction. All comparative studies were included in a meta-analysis to identify differences in operative time, ischemia time, surgical-site occurrence, microvascular complication, and partial or total flap loss between the two groups. All included studies (comparative and noncomparative) were used in the systematic review, summarizing the various flap characteristics, technical nuances, and functional and aesthetic outcomes. RESULTS: Twelve articles were included in the meta-analysis, representing 277 patients in the CAD/CAM group and 419 patients in the conventional group. CAD/CAM was associated with 65.3 fewer minutes of operating room time (95 percent CI, -72.7 to -57.9 minutes; p < 0.0001) and 34.8 fewer minutes of ischemia time (95 percent CI, -38 to -31.5 minutes; p < 0.0001). There were no significant differences in surgical-site occurrence, nonunion, flap loss, microvascular complications, or hardware-related complications. CONCLUSIONS: CAD/CAM is associated with shorter operating room and ischemia times. There are no significant differences in flap or hardware-related complications between CAD/CAM and conventional surgical planning.

Evaluation of fronto-orbital reconstruction surgery for the treatment of metopic synostosis in Chinese population.

PURPOSE: To evaluate the efficacy of fronto-orbit reconstruction surgery on pediatric metopic synostosis via an image-based 3D reconstruction in Chinese population. METHODS: Thirty pediatric metopic synostosis patients who received fronto-orbital reconstruction surgery in the Children's Hospital of Nanjing Medical University, Department of Neurosurgery, from January 2007 to December 2018 were analyzed in the study. Here we use the Mimics 20.0 software to reconstruct patients' cranial thin-section CT scan images from pre- and post-operation and control groups. Then the data of intracranial volume, frontal volume, orbital hypertelorism, ECA, ZF, and ORA were analyzed using the paired t-test or Wilcoxon matched-pairs signed-ranks test. RESULTS: The age of these patients was 15.83 ± 16.12 months. After surgery, the mean frontal volume was enlarged from 92.75 ± 26.97 to 138.62 ± 47.97 cm3 (P < 0.0001), and the intracranial volume was enhanced from 976.87 ± 230.83 to 1059.44 ± 217.98 cm3 (P < 0.0001). In the meantime, the ECA was changed from 108.02 ± 8.17 to 134 ± 5.59° (P < 0.0001). In line with the alteration of the parameters mentioned above, the head shapes in all patients were also significantly improved after the surgery with no obvious complications. CONCLUSION: Fronto-orbit reconstruction surgery is a safe and effective treatment for pediatric metopic synostosis. Computer-aided 3D reconstruction could serve as a quantitative strategy to evaluate the efficacy of craniofacial surgery.

Incidence of Odontogenic Disease in Patients With Pott's Puffy Tumor.

PURPOSE: Osteomyelitis with subperiosteal abscess of the frontal bone, or Pott's puffy tumor (PPT), is a rare but life-threatening condition. The relationship of concurrent dental disease to PPT has not been well described. This study sought to delineate the incidence of odontogenic disease in PPT, especially in cases where there is no history of facial trauma or prior frontal sinus surgery. METHODS: A retrospective chart review of patients diagnosed with PPT between 2010 and 2019 was carried out. Demographics, pertinent medical history, surgical procedures performed, and microbial cultures and antibiotics used were extracted for analysis. Maxillofacial computed tomography scans were reviewed for presence of odontogenic disease. RESULTS: A total of 17 patients were identified. Four had documented history of frontal bone trauma; 3 had previous frontal sinus surgery. Seven (41%) had documented odontogenic disease on initial radiology reports; however, upon dentist review, 16 (94%) had various pathology visible on their computed tomography scans. Twelve of these 16 patients had no previous frontal sinus trauma or surgery. Eight patients (47%) had only ipsilateral maxillary or ethmoid inflammation respective to PPT on computed tomography. Seventy-six percent of patients underwent endoscopic sinus surgery. Of 14 patients with cultures collected at the time of surgery, 7 (50%) had polymicrobial growth and 6 (43%) had anaerobic growth. CONCLUSIONS: The incidence of odontogenic disease in this population of PPT was 94%. In the absence of a history of frontal bone trauma or frontal sinus surgery, underlying dental origin should be suspected in cases of PPT. Initial radiology reports may not document all identifiable dental pathology. Therefore, patients presenting with PPT should undergo comprehensive evaluation, including an oral cavity and dental examination, and potential referral to dental colleagues.

A test of the Bulut et al. (2016) landmark-free method of quantifying sex differences in frontal bone roundness in a contemporary Czech sample.

The skull, along with the pelvic bone, serves an important source of clues as to the sex of human skeletal remains. The frontal bone is one of the most significant sexually dimorphic structures employed in anthropological research, especially when studied by methods of virtual anthropology. For this reason, many new methods have been developed, but their utility for other populations remains to be verified. In the present study, we tested one such approach-the landmark-free method of Bulut et al. (2016) for quantifying sexually dimorphic differences in the shape of the frontal bone, developed using a sample of the Turkish population. Our study builds upon this methodology and tests its utility for the Czech population. We evaluated the shape of the male and female frontal bone using 3D morphometrics, comparing virtual models of frontal bones and corresponding software-generated spheres. To do so, we calculated the relative size of the frontal bone area deviating from the fitted sphere by less than 1 mm and used these data to estimate the sex of individuals. Using our sample of the Czech population, the method estimated the sex correctly in 72.8% of individuals. This success rate is about 5% lower than that achieved with the Turkish sample. This method is therefore not very suitable for estimating the sex of Czech individuals, especially considering the significantly greater success rates of other approaches.

A Rare Case Report of Encephalocele with Numerous Ependymal Components: A Potential Diagnostic Pitfall.

Different cellular constituents of the central nervous system occurring in encephaloceles or neuroglial heterotopias (NGHs) have been reported, but the ependymal morphology has rarely been described in the previous literature, let alone the related histological images. To determine the ependymal morphology in encephaloceles or NGHs, we report a rare case of encephalocele with numerous ependymal components. Radiological examination showed that a 6.2 × 3.1 cm nasal dorsum mass-forming encephalocele in a 24-year-old woman, who had an intracranial connection through a frontal bone defect. This patient underwent a resection of the encephalocele under nasal endoscopy and a reconstruction of the cranial base. The patient had a good prognosis with no postoperative complications during follow-up. Microscopically, the ependymal components entrapped in a collagenized background showed numerous slit-like spaces lined by columnar cells with abundant palely eosinophilic cytoplasm and apical surface microvilli. With immunohistochemistry, in addition to the expression of EMA along with the slit-like spaces, GFAP and S100 were diffusely expressed in the slit-like spaces. In conclusion, the ependymal component in either encephaloceles or NGHs may present slit-like spaces arranged in an anastomosing pattern. The unusual morphology of ependyma continues to be underrecognized by pathologists and is easily misdiagnosed; therefore, an awareness of the morphological change in ependyma is necessary.

A rare case of hyperostosis frontalis interna in an 86-year-old Japanese female cadaver.

Hyperostosis frontalis interna (HFI) is a condition characterized by abnormal bone outgrowth on the inner surface of the frontal bone. Most HFI cases occur in post-menopausal elderly women. The pathology of HFI development is uncertain. The estimated incidence of HFI ranges from 5 to 12% in Western countries, but few cases have been reported in the Japanese population. Here, we report a case of HFI in an 86-year-old Japanese female cadaver. Macroscopically, the internal surface of the frontal bone exhibited bilateral nodular protrusion with sparing of the midline, while the external surface was normal. According to the morphological classification of HFI proposed by Hershkovitz et al. this case belongs to type D, the most severe type. Using computed tomography (CT), we defined five layers, designated as I-V from the inner to the outer layer, in the nodular region of HFI; however, the normal frontal bone is composed of three layers. Histological results demonstrated that layers I, III, and V consisted of the cortical bone, and layers II and IV consisted of the trabecular bone. We also observed increases in the numbers of lamellar bone and blood vessels on the dural side of layer I, indicating increased vascularization and active osteogenesis. These results indicate that layer II represents a new diploe within the inner table, which split into layers I and III, suggesting that diploization within the inner table by activated remodeling may be involved in the development of hyperostosis in this case.