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.

Comparison of the Effect of Platelet-rich Plasma (PRP) and Fat Graft on Autologous Bone Grafting in a Randomized-controlled Experimental Skull Model.

Gold standard method for the treatment of critical-sized bone defects is the autogenous bone grafting procedure. A number of new and potentially useful adjuncts currently are being investigated to enhance the success of bone grafting. We propose to evaluate the effect of the most known and easily obtained 2 biological materials, fat graft and platelet-rich plasma (PRP), on bone graft healing. Twenty-seven New Zealand male rabbits were included in this randomized, controlled study. Two-sided 15-mm diameter bone defects were created in the parietal bones and the bones taken were replaced right-to-left and vice versa with 1 control group, 1 fat graft applied group, and the last one PRP applied group. Histologic evaluation and 3-dimensional maxillofacial computerized tomography were performed and bone density was calculated. In radiologic analysis, bone density was significantly different in the PRP group compared with the control and fat graft group in the 12th week ( P <0.05). In histologic scoring analysis, the PRP group had a better score than the control and fat graft group, while the fat graft group was worse than the control group in the 6th week ( P <0.05). The addition of PRP had a positive effect whereas fat graft had a negative effect on bone graft healing compared with the control group.

[Topographic study of the parietal region for the elaboration of revascularized cranium vault autograft]. / Izuchenie topografo-anatomicheskikh osobennostei temennoi oblasti pri razrabotke revaskulyariziruemogo kostno-fastsial'nogo temennogo autotransplantata.

OBJECTIVE: Topographic and blood vessel architecture study of the parietal area and distal regional pool of the superficial temporal artery (STA) to assess the possibility of revascularized cranium vault bone autograft formation. MATERIAL AND METHODS: For the topographic and anatomical study, 30 non-fixed corpses (17 male and 13 female) were selected, the average age of which was 59±5 years. In the anamnesis and catamnesis, there were no indications of trauma or other pathology of the head and neck, including vascular. STA was contrasted with a non-radiocontrast dye (brilliant green) with the introduction of the dye into the STA with preliminary ligation of the frontal branch of the STA. The area of blood supply to soft tissue and bone structures was studied. The angioarchitectonics of the parietal region was studied, the feeding vessel of the studied flap was identified. RESULTS: The obtained anatomical landmarks for the collection of CPFP flap make it possible to form a flap with high accuracy and minimize the morbidity of the donor area.

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.

CRISPRai for simultaneous gene activation and inhibition to promote stem cell chondrogenesis and calvarial bone regeneration.

Calvarial bone healing remains difficult but may be improved by stimulating chondrogenesis of implanted stem cells. To simultaneously promote chondrogenesis and repress adipogenesis of stem cells, we built a CRISPRai system that comprised inactive Cas9 (dCas9), two fusion proteins as activation/repression complexes and two single guide RNA (sgRNA) as scaffolds for recruiting activator (sgRNAa) or inhibitor (sgRNAi). By plasmid transfection and co-expression in CHO cells, we validated that dCas9 coordinated with sgRNAa to recruit the activator for mCherry activation and also orchestrated with sgRNAi to recruit the repressor for d2EGFP inhibition, without cross interference. After changing the sgRNA sequence to target endogenous Sox9/PPAR-γ, we packaged the entire CRISPRai system into an all-in-one baculovirus for efficient delivery into rat bone marrow-derived mesenchymal stem cells (rBMSC) and verified simultaneous Sox9 activation and PPAR-γ repression. The activation/inhibition effects were further enhanced/prolonged by using the Cre/loxP-based hybrid baculovirus. The CRISPRai system delivered by the hybrid baculovirus stimulated chondrogenesis and repressed adipogenesis of rBMSC in 2D culture and promoted the formation of engineered cartilage in 3D culture. Importantly, implantation of the rBMSC engineered by the CRISPRai improved calvarial bone healing. This study paves a new avenue to translate the CRISPRai technology to regenerative medicine.

The character of parietal and orbital alterations in the superfamily Hominoidea (families Hominidae [exclusive of Homo] and Hylobotidae).

Parietal external surface disruption routinely referred to as porotic hyperostosis, and orbital alterations (cribra orbitalia), have been attributed to anemia-related bone marrow hyperplasia in humans. A recent study in humans identified that they were actually vascular in nature. Skeletons were examined and epi-illumination surface microscopy was performed on the parietal region and orbit of 156 Hominidae and 123 Hylobotidae to assess if these phenomena were trans-phylogenetic. Trans-cortical channels were recognized on the basis of visualized ectocranial surface defects penetrating the parietal; cribra orbitalia, by alteration of the normally smooth orbital roof appearance. Trans-cortical parietal channels, ranging in size from 20 to 100 µm, are rare in Gorilla and Pan troglodytes and absent in Pan paniscus. They are universally present in adult Pongo abeli and in Hylobatidae, independent of species. Cribra orbitalia was common in Hylobotidae, Pongo pygmaeus and P. abelii, less prevalent in adult P. troglodytes, and not recognized in any Gorilla gorilla or P. paniscus examined. The proliferative form predominated, with the exception of Hylobates concolor and muelleri, in which uncalcified vascular grooves predominated. No correlation was observed between the presence of either trans-cortical channels or cribra orbitalia and fractures, osteoarthritis, or inflammatory arthritis. Parietal alterations observed in apes are trans-cortical channels, analogous to those observed in humans, and do not represent porosity. Similarly, cribra orbitalia in apes is confirmed as vascular in nature. The proliferative form apparently represents calcification of blood vessel walls, indistinguishable from observations in humans. Predominant presence in adults rather than in juveniles suggests that both forms are acquired rather than developmental in derivation. Sex and bone alteration/disease-independence suggests that mechanical, endocrine, and inflammatory phenomena do not contribute to the development of either. Further, independent occurrence of trans-cortical channels and cribra orbitalia suggests that they do not have a shared etiology.

Skull fractures in abusive head trauma: a single centre experience and review of the literature.

PURPOSE: The authors provide a comprehensive framework with which to approach paediatric calvarial injury sustained as a result of suspected abusive head trauma (AHT). This is achieved through the presentation of a case series set in the context of the unique morphology of the infant skull and the possible diagnostic pitfalls which may arise due to the presence of variant anatomy or other mimicking conditions. METHODS: A retrospective analysis of sixty-three patients referred to our institution with suspected AHT was carried out. Seventeen patients with skull fractures were identified and their fractures were described in terms of anatomical location, type and course. Our data was then interpreted in the light of known anatomical fracture mimics and the available literature on the subject. RESULTS: Forty-two skull fractures were identified and described in our cohort, most of which were simple linear fractures of the parietal bones (33%). There were also a substantial number of complex stellate fractures, namely of the parietal (29%) and occipital (10%) bones. Eleven fracture mimics including accessory sutures and wormian bones were also identified in this cohort. CONCLUSIONS: Our study supports and builds on the existing literature, thereby offering a more complete view of the spectrum of calvarial damage sustained as a result of AHT in the context of its diagnostic pitfalls.

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.

Gorham-Stout disease with parietal bone osteolysis: a case series and review of literature.

BACKGROUND: Gorham-Stout disease (GSD) is a rare and idiopathic bone disorder, characterized by massive osteolysis. To date, there is no established treatment strategy for GSD. We empirically treated two patients, who had presented to us with cranial lesions of GSD. Here, we propose a novel algorithm for the management of Gorham's disease based on our experience and review the literature published to date. METHODS: We reviewed all existing literature on GSD describing the pathophysiology and suggested treatment methods, up to 2018. RESULTS: We found 13 papers with 14 reported cases; an inclusion of our two cases brings the total count up to just 16 recorded cases of GSD involving the skull. Of these, the base of the skull was affected in eight cases, while the remaining eight cases showed cranial involvement. The patients with skull-base involvement were managed conservatively, using medications or radiotherapy. The patients with cranial osteolysis were managed surgically, with an excision of the osteolytic portion, followed by cranioplasty. Of the latter group, the pericranium was not removed in one patient, in whom a very slight progression of the osteolytic process was later observed. CONCLUSIONS: The pathogenesis of GSD remains poorly understood. Further study is required to determine an optimum management strategy. A long-term follow-up will also be necessary to establish the effectiveness of the treatment process. The untreated patients show a progressive resorption of the affected bones of the skull. A painful, vanishing skull deformity is an alarming sign of GSD. Early diagnosis and treatment are necessary to arrest disease progression and to prevent complications.

Focal Idiopathic Calvarial Thinning: A Condition of Uncertain Prevalence and Significance.

ABSTRACT: Focal thinning of the calvarial bones unrelated to an underlying systemic disease is uncommon. Of such cases documented in the medical literature, most are bilateral parietal bone thinning, which tends to affect elderly females and results in bilateral symmetric, regularly shaped depressions of the skull. The authors describe 2 cases of unilateral, focal, irregularly shaped calvarial thinning in adolescent males that occurred without an obvious precipitating incident and were unrelated to systemic disease, a known syndrome or previous trauma. The nature and physical parameters of the deformities are demonstrated here and specific historic features such as age of onset and mode of obstetric delivery are explored. The clinical significance and potential pathogenesis of this finding is unclear, though these cases are relevant in highlighting a novel presentation that we henceforth term focal idiopathic calvarial thinning.

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.

Surgical Resection of a Parietal Osteoma in a Domestic Ferret Using Advanced Neurosurgical Techniques.

A 3.5 yr old male neutered ferret presented with progressive enlargement of a right dorsocaudal skull mass that had occurred over 18 mo. Computed tomography imaging revealed a large (2.4 × 2.7 cm), well-defined, pedunculated osseous mass arising from the right parietal bone. Cytology was inconclusive, and surgical biopsy was consistent with an osteoma. Further enlargement of the mass occurred over the next 3 mo, at which time surgical intervention was pursued. The patient recovered well, despite the persistence of a bony defect at the former mass site, and no mass regrowth occurred in the 14 mo following the surgical resection. This is one of only two reports in the literature to document the surgical removal of an osteoma in a ferret, and this is the sole case in which a custom apparatus was fabricated for head stabilization, a multiaxis adjustable surgical table was used to improve access to the surgical site, and an ultrasonic scalpel was used for the mass resection.

Characterization of the mechanical properties of human parietal bones preserved in modified larssen solution, formalin and as fresh frozen.

PURPOSE: Although the fresh frozen (FF) cadaver is preferred for surgical applications, it is limited due to short usage time, unsuitable for reuse and the risk of infection. Due to its limited use, FF cadavers, which are covered by import in countries with insufficient body donation cause low-cost effectiveness. With the increase of real human tissue specimen necessities for surgical training, long-term preservation of the cadavers is crucial due to changes in mechanical properties. Therefore, studies on embalming solutions have increased in recent years. METHODS: We quantify the biomechanical properties of human parietal bones preserved via modified larssen solution (MLS) and compare the results with the specimens preserved as FF and fixed with 10% formalin-based solution (F10). The rectangular samples of 24 parietal bones of male individuals were resected from MLS-embalmed, F10-embalmed and FF cadavers to form three groups each containing eight samples. These specimens were tested longitudinally to identify mechanical properties. RESULTS: The tensile test results showed that there is not a significant difference between the groups in terms of stiffness, elastic modulus, strain at ultimate stress, failure strain and effective plastic strain. However, the yield stress, ultimate stress, yield strain, failure stress and total energy and post-yield properties are significantly lower in F10 than MLS and FF groups. CONCLUSION: It is observed that the mechanical properties of MLS preserved and FF parietal bones have almost similar properties. Thus, it can be concluded that MLS is a suitable fixative solution for bone studies and bone-related surgical anatomy training applications.

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.

Pott's puffy tumour of the frontal and Parietal bones with subgaleal abscess as a complication of acute sinusitis - a case report.

Acute sinusitis is a frequent medical condition that can affect any age group and may lead infrequently to very serious life-threatening complications. These complications include the spread of infection to frontal and other cranial bones, meninges, and other intracranial structures that require urgent medical actions to prevent mortality and morbidity. We report the case of acute frontal sinusitis in a 14 years old male who presented with fever, severe headache, and fluctuant swelling of the nasal root, and right supraorbital and frontoparietal regions. Imaging studies demonstrated signs of left-sided sinusitis, osteomyelitis of the frontal bones, and right parietal bone. Urgent surgery was performed with drainage of the abscesses and samples were sent for culture and sensitivity. Bilateral antral washout and trephination of the left frontal sinus was performed and pus was evacuated. Growth of Staphylococcus aureus and Peptostreptococcus micros was reported and according to the sensitivity report, the patient was kept on intravenous meropenem, 1500 mg per day and vancomycin 1500 mg per day was added on the 7th postoperative day. The patient was discharged from the hospital in good health on the 25th postoperative day and kept on oral vancomycin for one month.

Effect of Induced Membrane on Guided Bone Regeneration in an Experimental Calvarial Model.

OBJECTIVE: The aim of this study was to evaluate the effect of induced membrane on guided bone regeneration and to compare its effect with poly-tetra-flourur-ethylene (PTFE) membrane and collagen membrane. METHODS: Sixteen white Vienna rabbits were used for experiments. Initially 1 defect was created on the parietal bone of all animals and cement was placed inside the defects. After 8 weeks, the bone cements were removed, without damaging the induced membrane formed in the defect cavity. And then 2 more defects were created. All defects were filled with xsenogenic graft materials and were covered with newly formed induced membrane, d-PTFE membrane and collagen membrane. Eight animals were sacrificed at 4th week and other 8 animals were sacrificed at 8th week and all bone specimens were histologically evaluated. RESULTS: New bone formation and bone marrow ratios were significantly higher in induced membrane and d-PTFE membrane group compared to collagen membrane group (P < 0.05) at 4th week. Mature bone ratios were significantly higher in induced membrane and d-PTFE membrane group compared to collagen membrane group (P < 0.05) at 8th week. The best CD31 value was detected with d-PTFE membrane group at 4th week and with induced membrane at 8th week. CONCLUSION: Induced membrane can act as a strong barrier membrane and stimulate bone regeneration. Induced membrane technique can be accepted as a good alternative for the reconstruction of critical size defects in maxillofacial region.

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.