Bilateral Foramina Parietalia Permagna - A Calvarial Defect Caused by Haploinsufficiency of the Msh Homeobox 2 Gene: A Case Report and Current Literature Review.

Foramina parietalia permagna (FPP) is a rare anatomical defect that affects the parietal bones of the human skull. FPP is characterized by symmetric perforations on either side of the skull, which are caused by insufficient ossification during embryogenesis. These openings are typically abnormally large and can range from a few millimeters to several centimeters in diameter. Enlarged foramina are often discovered incidentally during anatomical or radiological examinations and in most cases left untreated unless symptoms develop. Although this calvarial defect is usually asymptomatic, it may be accompanied by neurological or vascular conditions that can have clinical significance in certain cases. FPP is an inherited disorder and arises due to mutations in either Msh homeobox 2 (MSX2) or aristaless-like homeobox 4 (ALX4) genes. In almost all cases, one parent is affected. Clinical findings and diagnostic imaging typically contribute to determine the diagnosis.

Giant epidermoid cyst penetrating the skull: a case report and literature review.

Intracranial epidermoid cyst is a rare pseudotumor of the nervous system, accounting for 0.2%-1.8% of all intracranial tumors. It is usually located in the cerebellopontine Angle or parasellar area, with insipid onset, slow growth and usually less than 2 cm in diameter. Giant epidermoid cysts that invade the bone have rarely been reported in the literature. Herein, we report a case of giant ECs extradural to the parietal bone, penetrating the skull and continuing to expand outward. In addition, a systematic search of four authoritative databases was conducted to collect the relevant reports of giant epidermoid cyst with diameter > 5cm for the first time, and to discuss the clinical and radiographic features of patients with giant epidermoid cyst and the influence of treatment options.

Repair of Congenital Enlarged Parietal Foramina With Porous Polyethylene Implants.

Enlarged biparietal foramina is an autosomal dominant disorder that is caused by a failure of completion of ossification within the parietal bones. Enlarged parietal foramina measuring more than a few millimeters are uncommon. Even though spontaneous regression has been described, closure is rarely complete, and depending on the size of the resulting defect, an unprotected brain is a concern. There are few reports on the surgical management of persistent enlarged biparietal foramina. This is the first report describing our experience with a custom porous polyethylene implant.

Craniofacial orientation and parietal bone morphology in adult modern humans.

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.

Primary osteosarcoma of the parietal bone.

Osteosarcoma is the most common primary bone tumor and usually involves the long bones. Osteosarcoma of the skull, on the other hand, is relatively rare. Here, we present a 29-year-old man with a growing mass in the skull he first noticed after a fall while skateboarding. The initial clinical diagnosis was hematoma. While undergoing an evacuation surgery for a hematoma, a suspicious mass was detected which was biopsied. Histopathological evaluation showed high-grade osteosarcoma. The patient was referred to our hospital where he underwent definitive resection followed by adjuvant chemotherapy. His course was complicated by wound infection. Even though osteosarcoma of the skull is a rare finding, it should be suspected in a patient with a skull mass, and the history of prior head trauma does not exclude the diagnosis.

Accessory Cranial Suture Leading to Abnormal Head Shape.

ABSTRACT: Accessory cranial sutures have been described in the literature and are most commonly associated with the parietal bone. These sutures are typically identified incidentally and there have been no reported cases of accessory cranial sutures leading to abnormal head shape.The authors present the case of a 3-month-old patient with multiple congenital anomalies and an accessory parietal suture leading to abnormal head shape. The patient was successfully treated with cranial orthotic therapy. To our knowledge, this is the first reported case of an accessory cranial suture leading to abnormal head shape.

The parietal foramen anatomy: studies using dry skulls, cadaver and in vivo MRI.

OBJECTIVE: The aim of this study was to describe the anatomical features encountered in the parietal foramen in a series of 178 human bones and 123 head MRI examinations. A cadaveric specimen was also dissected to demonstrate the trajectory of a superficial scalp vein through the parietal foramen as far as the dura mater. A literature review was performed regarding prevalence of parietal foramen in different populations. METHODS: Totally, 178 paired adult bones were used to investigate the presence, shape and number of the parietal foramina. In addition, 123 brain MRI examinations were also studied. RESULTS: The parietal foramina were encountered in 75/89 (84.3%) skulls [32/38 (84.2%) in women vs. 43/51 (84.3%) in men, p > 0.05]. The parietal foramen was present bilaterally in 44.73% of females and 54.9% of males. Regarding unilaterality of the parietal foramen, a right or left laterality was observed in female 21% right versus 18% left; and 16% versus 14% (left) in males (p > 0.05). The accessory parietal foramen was present in the right parietal in 2.6% and in 7.9% on the left side of the females, while 5.9% and 3.9% of the males on the right or left sides, respectively. The parietal foramina located in the proximity of the sagittal suture (male 7.1 ± 2.5 mm vs. female, 7.4 ± 2.7 mm). There was a positive correlation between the right and left parietal foramina regarding the distance from the median line. The distance from a foramen to the contralateral one was 16 ± 4 mm in men and 18 ± 5 mm in women, respectively (p > 0.05). CONCLUSION: No major differences were encountered between sexes regarding the anatomical features of parietal foramen.

Characterization of Bilateral Parietal Thinning.

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 ±â€Š16 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 ±â€Š0.11 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.

Vascularized Composite Parietal Bone Flap for Immediate Reconstruction of a Hemi-Maxillectomy Defect in an Infant.

BACKGROUND: Surgical resection of maxillary tumors can result in defects that can be difficult to reconstruct by conventional means due to the complex functional and anatomic nature of the midface and lack of regional bone flap options in the head and neck. Many reconstructive methods have been used to repair maxillary defects, but the ideal technique for the reconstruction of hemi-maxillectomy defects in growing pediatric patients has yet to be determined. METHODS: The authors present a rare pediatric patient with melanotic neuroectodermal tumor of infancy resulting in a hemi-maxillectomy defect after resection that was reconstructed using a pedicled vascularized composite flap consisting of temporalis muscle, pericranium, and parietal bone. RESULTS: The patient achieved successful long-term bony reconstruction of his right maxilla with this flap. Stable skeletal fixation with adequate orbital support was maintained over a >3-year follow-up period. CONCLUSION: A vascularized composite parietal bone flap is a reliable reconstructive option for reconstruction of large maxillectomy defects providing low donor-site morbidity, adequate globe support, excellent long-term skeletal stability, and malar symmetry in rapidly growing pediatric patients. Successful reconstruction for a rare patient with maxillary melanotic neuroectodermal tumor of infancy requiring hemi-maxillectomy was demonstrated with >3-year follow-up.

Reconstruction of Congenital Cranial Defect Using Autologous Bone Graft in Aplasia Cutis Congenita.

Many methods have been devised to repair cranial defects. Here, we report the use of a simple technique for the repair of a congenital cranial defect associated with aplasia cutis congenita (ACC).A newborn baby at 39 weeks of gestation was consulted with a scalp and cranial defect at the vertex measuring 3 × 1.5 cm. A 3-D CT scan of the skull confirmed the presence of a cranial defect at the sagittal suture and a normal brain structure. On the 13 day of life, the newborn was taken to an operating room. An autologous bone graft was harvested from adjacent normal parietal bone and grafted into the debrided congenital cranial defect. The soft tissue defect was then covered by rotation flaps.The postoperative 3-D CT scan presented a well-positioned autologous bone graft. At 1 month postoperatively, the skull contour was normal and there was no palpable defect.We report a successful surgical outcome for a congenital cranial and soft tissue defect in ACC treated using an autologous bone graft and rotation flaps. Although conservative therapy may be an alternative option, we recommend appropriate surgical reconstruction in patients at risk of potentially fatal complications.

Effect of Morphogenetic Protein BMP-2 on X-Ray Density of Bone Defect in the Experiment.

In experiments on Wistar rats, a simulated defect in the flat bones of the skull was filled with a collagen sponge of animal origin impregnated with BMP-2 or pure sponge; in control rats, the defect was left open. During follow-up, X-ray density of the collagen sponge in the experimental groups differed significantly. The results attest to the absence of spontaneous remodeling of the bone tissue under conditions modeled focal defect. Moreover, stimulation of reparative processes by the collagen matrix did not lead to positive dynamics. Saturation of the collagen sponge with BMP-2 in a concentration of 0.05 mg/ml allowed increasing Xray density of the bone starting from week 4.

Rupture or traumatic dislocation of cranial suture on infants, involvement of the lambdoidal accessory bones (Wormian bones): case presentation and analysis.

BACKGROUND: Sutural or Wormian bones are accessory bones of genetic and hereditary relevance, considered as ethnic and anatomical variables. Recently, they have been related to a certain type of congenital alterations such as osteogenesis imperfecta; however, there is no description in the literature of their involvement in skull fractures in infants. CASE PRESENTATION: We present a case of a male patient aged 15 months who suffered a fall from the stairs of his home approximately 6 h before arrival in the emergency room. This fall of approximately 1 m in height and with an area of direct impact on the right occipito-parietal region with no apparent loss of consciousness. At admission, with a Glasgow of 14 for irritability with subgaleal hematoma and cranial endostosis on occipitoparietal region, no more neurological signs were present. A CT scan of the skull was performed showing an occipital-parietal discontinuity at the lambdoid suture, and the scan also showed that a displacement occurred below the thickness of the adjacent bone. In addition, radiographic evidence showed a high possibility of dural penetration and an area of adjacent hemorrhagic contusion. Due to these findings, a surgical approach was decided upon. The findings in the surgical procedure were a complete dislocation (rupture) of lambdoidal cranial suture on the occipital border of the accessory bone (Wormian bone) with dura mater tear on the rupture tracing. A craniotomy was performed with dural plasty without eventualities. Forty-eight hours after surgery, he was discharged home in a stable neurologic condition. CONCLUSIONS: The present report shows the implications of approaching this type of injury, which can be confused as a depressed skull fracture. There is no description in the literature of a sutural rupture associated with Wormian bones.

Bifrontal Biparietal Cruciate Decompressive Craniectomy in Pediatric Traumatic Brain Injury.

BACKGROUND: We investigated a novel surgical approach to decompressive craniectomy (DC), the bifrontal biparietal, or "cruciate," craniectomy, in severe pediatric traumatic brain injury (TBI). Cruciate DC was designed with a fundamentally different approach to intracranial pressure (ICP) control compared to traditional DC. Cruciate DC involves craniectomies in all 4 skull quadrants. The sagittal and coronal bone struts are disarticulated at the skull to allow the decompression of the sagittal sinus and bridging veins in addition to permitting cerebral expansion, thereby maintaining cranial compliance. OBJECTIVE: To characterize ICP control with cruciate DC in pediatric TBI. METHODS: We performed a retrospective review of TBI patients who underwent cruciate DC. We investigated mortality and preoperative and postoperative ICP. Group 1 underwent medical therapy prior to DC and Group 2 required immediate DC. RESULTS: Fifteen of 18 patients survived. In Group 1, mean preoperative ICP was 18.5 mm Hg and mean postoperative ICP was 11.5 mm Hg. In Group 2, mean preoperative ICP was 27.3 mm Hg and mean postoperative ICP was 15.0 mm Hg. CONCLUSION: Cruciate DC was associated with lowering ICP. We observed acute drops in ICP and long-term ICP control. The floating bone struts of the cruciate DC permits the decompression of the sagittal sinus and bridging veins, with maximal relief of cerebral edema.

Assessment of Bioabsorbable Hydroxyapatite for Cranial Defect in Children.

PURPOSE: To evaluate the utility and efficacy of bioabsorbable hydroxyapatite and collagen complex (HA/Col) for cranioplasty repair of cranial bone defects in children. METHODS: Two patients (a 6-year-old male and 11-year-old female) with Treacher Collins syndrome received zygoma and orbital floor reconstruction using a full thickness of parietal bone. The bone grafts were taken from each patient's parietal cranium. The right parietal cranial defect was repaired with autologous bone dust, and the left side was repaired with HA/Col in each patient. Computed tomography scans were taken immediately after and at 12 months following surgery. The osteosynthesis areas and thicknesses were measured using computer-aided engineering. RESULTS: Both patients experienced no complications, including infection. In the 6- and 11-year-old patients, the extent of osteosynthesis for HA/Col was 92.2% and 89.4%, respectively; and for the autologous bone dust was 78.5% and 53.2%, respectively. Because of the small sample size, a significant difference could not be calculated; however, the percentage of osteosynthesis for HA/Col was higher than for the autologous bone dust. CONCLUSION: This study showed that HA/Col can be effectively used in cranial defects and can be considered an alternative graft material for cranial reconstruction.

Evaluation of the Biocompatibility of CS-Graphene Oxide Compounds In Vivo.

In the last few years, graphene oxide (GO) has gained considerable importance in scaffold preparation for tissue engineering due to the presence of functional groups that allow the interaction between the extracellular matrix and the components of the cellular membrane. The interaction between GO and chitosan (CS) can not only improve the biomechanical properties of the scaffold but also generate a synergistic effect, facilitating tissue recovery. In vivo studies on GO are scarce; therefore, biocompatibility tests on CS-GO scaffolds and bone regeneration experiments on critical size defects were carried out on Wistar rats. Scaffolds made of CS, CS-GO 0.5%, and CS-GO 1% were prepared and implanted on Wistar rats cranial bones for three months. Scaffold samples were analyzed through histochemistry and scanning electron microscopy. The analysis performed showed reabsorption of the material by phagocytic activity and new bone formation. The CS-GO 0.5% formulation gave the best performance in bone regeneration, with excellent biocompatibility. These results show the potential of this compound for tissue regeneration opening and medical applications.

Evaluation of three-dimensional superimposition technique on parietal bone of the puberty beagle dogs.

OBJECTIVES: This study aimed to (a) evaluate the stability of the parietal bone of 6-9 months old beagles and (b) examine whether parietal regional superimposition can provide an atraumatic and effective solution for further maxillary expansion study. MATERIALS AND METHODS: Six prepubertal 6-month-old male beagles were included. Six miniscrew markers were inserted into the left and right sides of the parietal bone, and two of them were placed bilaterally near the palatal suture. The subjects were scanned with cone beam computed tomography (CBCT) at three time points of T0 (6 months old), T1 (7.5 months old) and T2 (9 months old), respectively. All skull models were analyzed by both the miniscrew superimposition and the parietal regional superimposition. RESULTS: The two superimposition methods had no significant difference (p > 0.05) in displacements of miniscrew markers between left and right first premolars (PM1). The maxillary superimposition between T0 and T2 indicated that the length and width of the maxillary as well as the width of the zygoma root increased significantly (p < 0.05), while the height of maxillary had no significant difference (p > 0.05) over the 3 months. CONCLUSIONS: The parietal bone is relatively stable for beagles from 6 months old to 9 months old and thus can be used as a reference region for 3D skull model superimposition of the beagle dog.

Recombinant bone morphogenetic protein-2 and platelet-derived growth factor-BB for localized bone regeneration. Histologic and radiographic outcomes of a rabbit study.

OBJECTIVES: Improvement in localized bone regeneration is needed to avoid the use of autogenous tissue. For that purpose, the use biologic mediators was proposed. The aim was to test whether or not one of two biologic mediators, recombinant human bone morphogenetic protein-2 (rhBMP-2) or recombinant platelet-derived growth factor (rhPDGF-BB), is superior to the other and to control groups for localized bone regeneration. MATERIALS AND METHODS: Four cylinders (height: 5 mm; diameter: 7 mm) were screwed on the parietal and frontal bones at the cranium in 12 rabbits. The cylinders either received (i) deproteinized bovine bone mineral (DBBM) mixed rhBMP-2 (DBBM/BMP-2), (ii) DBBM mixed with rhPDGF-BB (DBBM/PDGF), (iii) DBBM (DBBM), and (iv) empty control (control). Rabbits were euthanized at 2 and 8 weeks (n = 6, respectively). Conventional histomorphometric and micro-CT analyses were performed. Parametric linear mixed models were applied for the analyses with Bonferroni correction for the multiple group comparisons. RESULTS: The area of bone regeneration (histology; AAHisto ) at 2 weeks peaked for DBBM (41.91%) with statistically significantly greater values compared to DBBM/PDGF and the control group (P < 0.05). At 8 weeks, mean AAHisto values were 96.29% (DBBM/BMP-2), 46.37% (DBBM/PDFG), 39.66% (DBBM), and 35.98% (control) (DBBM/BMP-2 vs. all groups (P < 0.05)). At 8 weeks, bone regeneration was greatest for DBBM/BMP-2 (35.62%) with statistically significant differences compared to all other groups (P < 0.05). The area of bone regeneration (micro-CT; AAm-CT ) at 2 weeks amounted to 43.87% (DBBM/BMP-2), 42.81% (DBBM/PDFG), 48.71% (DBBM), and 0.96% (control). The control group demonstrated statistically significantly less AAm-CT compared to all groups (P < 0.05). At 8 weeks, mean AAm-CT values were 63.65% (DBBM/BMP-2), 50.21% (DBBM/PDFG), 44.81% (DBBM), and 4.57% (control) (P > 0.05). CONCLUSIONS: The use of rhBMP-2 significantly enhanced bone regeneration compared to all other groups including the group with rhPDGF-BB.

[Eosinophilic granuloma of the parietal bone of an adult patient with BRAF mutation]. / Éozinofil'naia granulema temennoi kosti s mutatsiei gena BRAF u vzroslogo patsienta.

The paper describes a case of eosinophilic granuloma of the parietal bone in a 32-year-old man. Histological examination revealed a large number of bean-shaped Langerhans cell histiocytes with lobed nuclei and nuclear grooves. The histiocytes alternated with the foci of obvious eosinophilic infiltration and with eosinophilic microabscesses. There were osteoclast-like multinucleated giant cells, bone resorption, and numerous bone rods covered with osteoblast chains. The histiocytes expressed CD1α, langerin, CD68, S100, and p53 (in 90.0% of the tumor cells). The Ki-67 proliferation index was 18.0%. A molecular genetic study identified BRAFV600E mutation (nucleotide substitution s.1799 T>A (p.V600E) in the heterozygous state). Clinical and morphological data and the results of molecular genetic studies led to the conclusion that there was eosinophilic granuloma of the right parietal bone (the unifocal form of Langerhans cell histiocytosis (LCH), type I, group A1, with the monoossal nature of lesion and with BRAFV600E mutation). In adults, this disease is extremely rare (2-5 cases of LCH per million people, bone loss in the fourth decade of life in 2.5% of the patients).

Mice lacking the conserved transcription factor Grainyhead-like 3 (Grhl3) display increased apposition of the frontal and parietal bones during embryonic development.

BACKGROUND: Increased apposition of the frontal and parietal bones of the skull during embryogenesis may be a risk factor for the subsequent development of premature skull fusion, or craniosynostosis. Human craniosynostosis is a prevalent, and often serious embryological and neonatal pathology. Other than known mutations in a small number of contributing genes, the aetiology of craniosynostosis is largely unknown. Therefore, the identification of novel genes which contribute to normal skull patterning, morphology and premature suture apposition is imperative, in order to fully understand the genetic regulation of cranial development. RESULTS: Using advanced imaging techniques and quantitative measurement, we show that genetic deletion of the highly-conserved transcription factor Grainyhead-like 3 (Grhl3) in mice (Grhl3 -/- ) leads to decreased skull size, aberrant skull morphology and premature apposition of the coronal sutures during embryogenesis. Furthermore, Grhl3 -/- mice also present with premature collagen deposition and osteoblast alignment at the sutures, and the physical interaction between the developing skull, and outermost covering of the brain (the dura mater), as well as the overlying dermis and subcutaneous tissue, appears compromised in embryos lacking Grhl3. Although Grhl3 -/- mice die at birth, we investigated skull morphology and size in adult animals lacking one Grhl3 allele (heterozygous; Grhl3 +/- ), which are viable and fertile. We found that these adult mice also present with a smaller cranial cavity, suggestive of post-natal haploinsufficiency in the context of cranial development. CONCLUSIONS: Our findings show that our Grhl3 mice present with increased apposition of the frontal and parietal bones, suggesting that Grhl3 may be involved in the developmental pathogenesis of craniosynostosis.