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Surgical Neurology International 2023Osseous hyperpigmentation of the calvarium is an extremely rare finding with only few reported cases in literature.
BACKGROUND
Osseous hyperpigmentation of the calvarium is an extremely rare finding with only few reported cases in literature.
CASE DESCRIPTION
The case is of a 59-year-old Caucasian male who presented with an acute history of generalized tonic clonic seizures and progressive weakness of the right upper limb. He had a background history of a malignant melanoma which had been resected from his left external acoustic meatus 4 weeks prior. Neuroimaging of the brain showed an intra-axial space-occupying lesion in his left parietal lobe with no associated osseous changes. A left mini parietal craniotomy was performed which revealed black discoloration of the parietal bone. The lesion was successfully resected and the bone flap was secured back in place. The patient was discharged on the 4 day postoperatively with no complications. The unusual finding of black discoloration of the calvarium was found to be secondary to adolescent tetracycline use.
CONCLUSION
Calvarial hyperpigmentation is a phenomenon encountered incidentally and will often come as surprise for surgeons. Once encountered, thorough history taking and examination should be done to investigate the cause.
PubMed: 37680939
DOI: 10.25259/SNI_493_2023 -
Current Biology : CB Jul 2017The posterior parietal cortex, along with temporal and prefrontal cortices, is one of the three major associative regions in the cortex of the mammalian brain. It is...
The posterior parietal cortex, along with temporal and prefrontal cortices, is one of the three major associative regions in the cortex of the mammalian brain. It is situated between the visual cortex at the caudal pole of the brain and the somatosensory cortex just behind the central sulcus. Technically, any cortex covered by the parietal bone is referred to as 'parietal cortex', but the posterior sector, formally referred to as posterior parietal cortex, is indeed its own functional section of cortex, consisting of Brodmann's areas 5, 7, 39, and 40 in humans, areas 5 and 7 in macaques, and area 7 in rodents (Figure 1). Whereas the anterior parietal cortex in humans comprises primary somatosensory areas, the posterior parietal cortex has several higher-order functions. It is referred to as an 'associative' cortical region because it is neither strictly sensory nor motor, but combines inputs from a number of brain areas including somatosensory, auditory, visual, motor, cingulate and prefrontal cortices, and it integrates proprioceptive and vestibular signals from subcortical areas.
Topics: Animals; Humans; Mammals; Parietal Lobe
PubMed: 28743011
DOI: 10.1016/j.cub.2017.06.007 -
Cancers Feb 2022Meningiomas are the most common tumor of the central nervous system and can result in skeletal manifestations, including hyperostosis of the adjacent cranial bone,... (Review)
Review
Meningiomas are the most common tumor of the central nervous system and can result in skeletal manifestations, including hyperostosis of the adjacent cranial bone, enostoses, depressions, and enhanced vascular impressions. However, their identification in the paleopathological literature has been rare and few cases have received broad acceptance of the diagnosis. A review of the literature identified some 43 cases in which individuals were argued to have suffered from meningiomas. Most were seen in older individuals but were more likely to affect males. Eleven individuals exhibited hyperostosis, the most easily recognized indicator, usually located on the parietal bone; the hyperostotic region averaged 8 cm in diameter and 3.0 cm in height. Seven displayed lytic lesions with areas much smaller in size than the hyperostosis, and many had vascular changes. The other cases had indicators that varied greatly in terms of location and expression and included both sclerotic lesions and hollow areas. Several authors also suggested other possible causes of the lesions. The findings reflect the non-pathognomonic nature of the effects of meningiomas. However, given their likely frequency and potentially severe effects in ancient people, it is argued that they should be taken into consideration more frequently when performing differential diagnoses.
PubMed: 35205806
DOI: 10.3390/cancers14041058 -
The Journal of Craniofacial Surgery Sep 2018The authors describe a case of congenital calvarial hemangioma successfully managed using propranolol therapy. Presenting symptoms, radiological and pathological...
OBJECTIVES
The authors describe a case of congenital calvarial hemangioma successfully managed using propranolol therapy. Presenting symptoms, radiological and pathological features, differential diagnosis, and management of this rare congenital mass are described.
CASE PRESENTATION
A 2-year-old boy presented with a 1-year history of a growing right parietal skull mass. No obvious etiology was apparent. No focal neurological deficits or associated craniofacial anomalies were identified. Plain film imaging demonstrated focal thickening of the right parietal bone with internal trabeculations in a sunburst appearance. Computed tomography (CT) scan showed bone thickening with coarsening of the bony trabeculae, minor irregularity of the outer table, unaffected inner table, and no evidence of aggressive features. A diagnostic biopsy of the lesion was performed in the operating room. Microscopic examination was consistent with hemangioma. Based on histological and radiological features of the lesion, it was identified as a cavernous hemangioma. Medical treatment utilizing propranolol was initiated for over 3 years with interval reduction in the lesion size. MRI head following treatment with propranolol demonstrated reduction of the mass compared to preoperative imaging.
CONCLUSIONS
Although a rare entity, it is important to consider congenital calvarial hemangioma in the differential diagnosis of slow growing skull lesions due to the possibility of complications as a result of the hemangioma's intracranial extension, and the potential for treatment. En bloc resection has classically been described as a treatment for such lesions, although our case demonstrates that medical treatment with propranolol therapy may be appropriate in certain situations.
Topics: Child, Preschool; Hemangioma, Cavernous; Humans; Male; Parietal Bone; Propranolol; Skull Neoplasms; Vasodilator Agents
PubMed: 29742579
DOI: 10.1097/SCS.0000000000004613 -
Journal of Anatomy Feb 2022In adult humans, the orbits vary mostly in their orientation in relation to the frontal bone profile, while the orientation of the cranial base and face are associated...
In adult humans, the orbits vary mostly in their orientation in relation to the frontal bone profile, while the orientation of the cranial base and face are associated with the anteroposterior dimensions of the parietal bone. Here we investigate the effect of parietal bone length on the orientation of the orbits, addressing craniofacial integration and head orientation. We applied shape analysis to a sample of computed tomography scans from 30 adult modern humans, capturing the outlines of the parietal and frontal bones, the orbits, and the lateral and midline cranial base, to investigate shape variation, covariation, and modularity. Results show that the orientation of the orbits varies in accordance with the anterior cranial base, and in association with changes in parietal bone longitudinal extension. Flatter, elongated parietal bones are associated with downwardly oriented orbits and cranial bases. Modularity analysis points to a significant integration among the orbits, anterior cranial base, and the frontal profile. While the orbits are morphologically integrated with the adjacent structures in terms of shape, the association with parietal bone size depends on the spatial relationship between the two blocks. Complementary changes in orbit and parietal bone might play a role in accommodating craniofacial variability and may contribute to maintain the functional axis of the head. To better understand how skull morphology and head posture relate, future studies should account for the spatial relationship between the head and the neck.
Topics: Adult; Face; Frontal Bone; Head; Humans; Parietal Bone; Skull; Skull Base
PubMed: 34498271
DOI: 10.1111/joa.13543 -
Mechanical and morphological properties of parietal bone in patients with sagittal craniosynostosis.Journal of the Mechanical Behavior of... Jan 2022Limited information is available on the effect of sagittal craniosynostosis (CS) on morphological and material properties of the parietal bone. Understanding these...
Limited information is available on the effect of sagittal craniosynostosis (CS) on morphological and material properties of the parietal bone. Understanding these properties would not only provide an insight into bone response to surgical procedures but also improve the accuracy of computational models simulating these surgeries. The aim of the present study was to characterise the mechanical and microstructural properties of the cortical table and diploe in parietal bone of patients affected by sagittal CS. Twelve samples were collected from pediatric patients (11 males, and 1 female; age 5.2 ± 1.3 months) surgically treated for sagittal CS. Samples were imaged using micro-computed tomography (micro-CT); and mechanical properties were extracted by means of micro-CT based finite element modelling (micro-FE) of three-point bending test, calibrated using sample-specific experimental data. Reference point indentation (RPI) was used to validate the micro-FE output. Bone samples were classified based on their macrostructure as unilaminar or trilaminar (sandwich) structure. The elastic moduli obtained using RPI and micro-FE approaches for cortical tables (E 3973.33 ± 268.45 MPa and E 3438.11 ± 387.38 MPa) in the sandwich structure and diploe (E1958.17 ± 563.79 MPa and E 1960.66 ± 492.44 MPa) in unilaminar samples were in strong agreement (r = 0.86, p < .01). We found that the elastic modulus of cortical tables and diploe were correlated with bone mineral density. Changes in the microstructure and mechanical properties of bone specimens were found to be irrespective of patients' age. Although younger patients are reported to benefit more from surgical intervention as skull is more malleable, understanding the material properties is critical to better predict the surgical outcome in patients <1 year old since age-related changes were minimal.
Topics: Child; Craniosynostoses; Female; Humans; Infant; Parietal Bone; X-Ray Microtomography
PubMed: 34773914
DOI: 10.1016/j.jmbbm.2021.104929 -
Folia Morphologica 2021The parietal foramen (PF) is a small inconsistent aperture located at the border of the middle 1/3 and posterior 1/3 of the parietal bone near the sagittal suture and is...
BACKGROUND
The parietal foramen (PF) is a small inconsistent aperture located at the border of the middle 1/3 and posterior 1/3 of the parietal bone near the sagittal suture and is considered an emissary foramen. Cranial emissary foramina are of utmost importance due to the structures that traverse the foramen. Variations in these foramina are common. Knowledge of the PF is important when performing neurosurgical procedures as the emissary vessels are at risk.
MATERIALS AND METHODS
The present study used 100 dry adult calvaria to determine the frequency of PF, the diameter of the PF, as well as topography of the PF (using the sagittal suture as an anatomical landmark).
RESULTS
A total of 32% of calvaria had PF present bilaterally; whilst 35% of calvaria had unilateral PF. The study also reports 5% calvaria in which PF were present on the sagittal suture. The mean diameter recorded was 1.55 mm (0.74-3.08 mm), and the mean distance between the lateral margin of the PF and the sagittal suture was 9.02 mm (4.44-18.20 mm).
CONCLUSIONS
Knowledge of the incidence and topography of the PF may aid neurosurgeons in creating and adjusting techniques and procedures in order to mitigate the risk of injury to emissary veins and other structures emerging from the PF.
Topics: Cranial Sutures; Incidence; Parietal Bone; Sphenoid Bone; Veins
PubMed: 33241848
DOI: 10.5603/FM.a2020.0140 -
The Journal of Craniofacial Surgery 2020Bilateral parietal thinning (BPT) of the calvarium is uncommon but can lead to significant morbidity, including pain or communication through the thinned bone. This...
BACKGROUND
Bilateral parietal thinning (BPT) of the calvarium is uncommon but can lead to significant morbidity, including pain or communication through the thinned bone. This study aimed to define and characterize a novel grading system for BPT.
METHODS
Coronal CT scans of patients with BPT were retrospectively analyzed and anatomic measurements were taken including (1) thinning ratio, defined as calvarial thickness at the thinnest point divided by the average thickness of the surrounding bone and (2) width of the defect. In addition, patient demographics and comorbidities were collected.
RESULTS
Forty-three patients were identified with BPT, with an average age of 73 ± 16 years and 74% were female. The authors' novel grading scheme based on depth of calvarium involvement was found to be significantly correlated to thinning ratio (P < 0.001) and width (P < 0.001). When controlling for comorbidities, increasing age (P = 0.044) was the only significant independent risk factor associated with thinning ratio. With respect to defect size, when controlling for comorbidities, both hypertension (P = 0.025) and increasing age (P = 0.024) were found to be significant independent risk factors related to increasing defect size. Twenty patients (47%) had multiple CT scans (range 5 month-5 year interval). In this group, patients had an average of 0.66 ± 0.11 mm decrease in parietal thickness per each year of increasing age, showing progressive parietal thinning with time.
CONCLUSION
This study proposes a novel quantitatively-characterized grading scheme for BPT. The authors' results indicate that when controlling for comorbidities, BPT thinning is associated with increasing age, while defect width is associated with increasing age and hypertension. This grading scheme can help to diagnose, classify, and monitor patients with parietal bone thinning.
Topics: Adult; Aged; Aged, 80 and over; Bone Diseases; Female; Humans; Male; Middle Aged; Parietal Bone; Retrospective Studies; Risk Factors; Tomography, X-Ray Computed
PubMed: 32049899
DOI: 10.1097/SCS.0000000000006241