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Michael I Siegel - One of the best experts on this subject based on the ideXlab platform.
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fluctuating dental asymmetry in rabbits with familial nonsyndromic Coronal Suture synostosis
Dentistry 3000, 2017Co-Authors: Mae A Hyre, Michael I Siegel, Gregory M Cooper, James R Gilbert, Seth M Weinberg, Mark P MooneyAbstract:Fluctuating dental asymmetry has been linked to conditions of unstable pre- and peri-natal development. Familial, nonsyndromic craniosynostosis disrupts early craniofacial development through localized excessive calvarial ossification leading to the premature fusion of the calvarial Sutures. Such abnormal gene expression may also produce systemic stress resulting in developmental instability, thereby affecting normal trait symmetry. The present study was designed to test this hypothesis by examining fluctuating dental asymmetry in an inbred strain of rabbits with familial, nonsyndromic Coronal craniosynostosis. The mesiodistal (MD) and buccolingual (BL) dimensions of the right and left maxillary first molars were measured in four groups of New Zealand white rabbits (N=176; n=40 with early-onset synostosis, n=65 with delayed-onset synostosis, n=46 in-colony, phenotypically normal rabbits, and n=25 wild-type normal controls). For each variable, raw signed asymmetry was calculated (left-right) and tested for assumptions of fluctuating asymmetry (i.e., normality and non-directionality). Any group that did not meet these assumptions was excluded from further analysis. Using a standard size-adjusted, fluctuating asymmetry index, mean fluctuating asymmetry was calculated and compared across groups with non-parametric statistics. For the MD dimension, no significant (p > 0.05) group differences in mean fluctuating asymmetry were observed among groups. In contrast, rabbits with early-onset synostosis had significantly (p < 0.05) more fluctuating asymmetry in the BL dimension compared to wild-type controls. Results demonstrate increased fluctuating dental asymmetry in rabbits with nonsyndromic, early-onset Coronal Suture synostosis and suggest that the molecular events producing Suture synostosis locally may have also have systemic effects. Knowledge of these systemic interactions may contribute to a fuller understanding of the phenotypic spectrum observed in individuals with nonsyndromic craniosynostosis.
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relaxin does not rescue Coronal Suture fusion in craniosynostotic rabbits
The Cleft Palate-Craniofacial Journal, 2012Co-Authors: James Cray, Michael I Siegel, Anne M Burrows, Gregory M Cooper, Lisa Vecchione, Christopher R Kinsella, Joseph E Losee, Amr M Moursi, Mark P MooneyAbstract:Objectives: Craniosynostosis affects 1 in 2000 to 3000 live births and may result in craniofacial and neural growth disturbances. Histological data have shown that thick collagenous bundles are present in the sutural ligament, which may tether the osteogenic fronts, resulting in premature fusion. The hormone relaxin has been shown to disrupt collagen fiber organization, possibly preventing craniosynostosis by relaxing the sutural ligament and allowing osteogenic fronts to separate normally and stay patent. This study tested this hypothesis with a rabbit model of delayed-onset Coronal Suture synostosis. Methods: A total of 18 New Zealand White rabbits with craniosynostosis were randomly assigned to one of three groups: sham control, protein control (BSA), relaxin treatment. After initial diagnosis, sham surgery, BSA, or relaxin was delivered to the fusing Coronal Suture in a slow-release (56-day) collagen vehicle. Longitudinal radiographs and body weights were collected at 10, 25, 42, and 84 days of age, a...
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Effects of Flutamide Therapy on Craniofacial Growth and Development in a Model of Craniosynostosis
Journal of Craniofacial Surgery, 2010Co-Authors: James Cray, Michael I Siegel, Anne M Burrows, Lisa Vecchione, Joseph E Losee, Emily L. Lensie, Gary E. Decesare, Andrew Campbell, David N. Finegold, Gregory M CooperAbstract:Abstract Research has implicated the faulty regulation of transforming growth factor β signaling as one mechanism for premature calvaria Suture fusion. Androgens have been shown to increase the expression and activity of the transforming growth factor β, resulting in increased osteoblast proliferation and differentiation and possibly premature Suture fusion. The present study was designed to test the hypothesis that flutamide, an androgen receptor-blocking agent, would "rescue" a Coronal Suture destined to fuse and improve craniofacial growth in a familial rabbit model of craniosynostosis. Thirty rabbits with delayed-onset, Coronal Suture synostosis were examined via longitudinal cephalometry. The rabbits were divided into 4 groups: (1) sham surgical controls (n = 10), (2) bovine serum albumin (500 ng) protein controls (n = 6), (3) flutamide diluent controls (n = 6), and (4) flutamide (15 mg dissolved in ethanol) experimental group (n = 8). At 10 days of age, radiopaque amalgam markers were implanted in all rabbits on either side of the Coronal Suture to monitor sutural growth. At 25 days of age, the bovine serum albumin, ethanol, and flutamide were combined with a slow-resorbing collagen vehicle and injected subperiosteally above the Coronal Suture into the respective groups. Although results revealed a slight but significant increase in Coronal Suture marker separation in flutamide-treated rabbits compared with controls at 42 days of age, few significant differences were noted for craniofacial growth and intracranial volume among groups. Results suggest that androgen receptor-blocking using flutamide may only provide a transient rescue to Suture fusion in this model. Further research is needed to investigate the effects of hormones on Suture development and maintenance.
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Craniosacral therapy : The effects of cranial manipulation on intracranial pressure and cranial bone movement
Journal of Orthopaedic & Sports Physical Therapy, 2006Co-Authors: Patricia A. Downey, Michael I Siegel, Timothy Barbano, Rupali Kapur-wadhwa, James J. Sciote, Mark P MooneyAbstract:Study Design Quasi-experimental design. Objectives To determine if physical manipulation of the cranial vault Sutures will result in changes of the intracranial pressure (ICP) along with movement at the Coronal Suture. Background Craniosacral therapy is used to treat conditions ranging from headache pain to developmental disabilities. However, the biological premise for this technique has been theorized but not substantiated in the literature. Methods Thirteen adult New Zealand white rabbits (oryctolagus cuniculus) were anesthetized and microplates were attached on either side of the Coronal Suture. Epidural ICP measurements were made using a NeuroMonitor transducer. Distractive loads of 5, 10, 15, and 20 g (simulating a craniosacral frontal lift technique) were applied sequentially across the Coronal Suture. Baseline and distraction radiographs and ICP were obtained. One animal underwent additional distractive loads between 100 and 10 000 g. Plate separation was measured using a digital caliper from the ...
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Intracranial pressure changes in craniosynostotic rabbits.
Plastic and Reconstructive Surgery, 2004Co-Authors: Wendy Fellows-mayle, Michael I Siegel, Ronal Mitchell, James P Bradley, H. Wolfgang Losken, Mark P MooneyAbstract:Cranial vault and brain deformities in individuals with craniosynostosis are thought to result, in part, from changes in intracranial pressure, but clinical findings are still inconclusive. The present study describes intracranial pressure changes in a rabbit model with naturally occurring, uncorrected Coronal Suture synostosis. Longitudinal and cross-sectional intracranial pressure data were collected from 241 New Zealand White rabbits, divided into four groups: normal controls (n = 81); rabbits with delayed-onset Coronal Suture synostosis (n = 78); rabbits with early-onset unilateral Coronal Suture synostosis (n = 32); and rabbits with early-onset bilateral Coronal Suture synostosis (n = 50). Epidural intracranial pressure measurements were obtained at 10, 25, 42, and 84 days of age using a NeuroMonitor microsensor transducer. Normal rabbits and rabbits with delayed-onset Coronal Suture and early-onset unilateral Coronal Suture synostosis showed a similar oscillating pattern of age-related changes in normal and head-down intracranial pressure from 10 to 84 days of age. In contrast, rabbits with early-onset bilateral Coronal Suture synostosis showed markedly elevated normal and head-down intracranial pressure levels from 10 to 25 days and showed a different pattern through 84 days. Results from one-way analysis of variance revealed significant (p < 0.01) group differences only at 25 days of age. Rabbits with early-onset bilateral Coronal Suture synostosis had significantly (p < 0.05) greater normal and head-down intracranial pressure (by 42 percent) than the other three groups. These results showed differing intracranial pressure compensations in rabbits with uncorrected multiple-Suture synostosis compared with normal rabbits or rabbits with uncorrected single-Suture synostosis, possibly through progressive cerebral atrophy and decreased intracranial volume, abnormal intracranial vascular patterns and blood volume, and/or differing cranial vault compensatory changes.
Mark P Mooney - One of the best experts on this subject based on the ideXlab platform.
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rescue of premature Coronal Suture fusion with tgf β2 neutralizing antibody in rabbits with delayed onset synostosis
The Cleft Palate-Craniofacial Journal, 2018Co-Authors: Mark P Mooney, Timothy D Smith, Anne M Burrows, Gregory M Cooper, James Cray, Jocelyn M Shand, John F Caccamese, James R GilbertAbstract:Objectives: An overexpression of Tgf-β2 leads to calvarial hyperostosis and Suture fusion in individuals with craniosynostosis. Inhibition of Tgf-β2 may help rescue fusing Sutures and restore normal growth. The present study was designed to test this hypothesis. Design: Twenty-eight New Zealand White rabbits with delayed-onset Coronal synostosis had radiopaque markers placed on either side of the Coronal Sutures at 10 days of age. The rabbits were randomly assigned to: (1) sham control rabbits (n = 10), (2) rabbits with control IgG (100 μg/Suture) delivered in a collagen vehicle (n = 9), and (3) rabbits with Tgf-β2 neutralizing antibody (100 μg/Suture) delivered in a collagen vehicle (n = 9). Longitudinal growth data were collected at 10, 25, 42, and 84 days of age. Sutures were harvested at 84 days of age for histomorphometry. Results: Radiographic analysis showed significantly greater (P < .05) Coronal Suture marker separation, craniofacial length, cranial vault length, height, shape indices, cranial...
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fluctuating dental asymmetry in rabbits with familial nonsyndromic Coronal Suture synostosis
Dentistry 3000, 2017Co-Authors: Mae A Hyre, Michael I Siegel, Gregory M Cooper, James R Gilbert, Seth M Weinberg, Mark P MooneyAbstract:Fluctuating dental asymmetry has been linked to conditions of unstable pre- and peri-natal development. Familial, nonsyndromic craniosynostosis disrupts early craniofacial development through localized excessive calvarial ossification leading to the premature fusion of the calvarial Sutures. Such abnormal gene expression may also produce systemic stress resulting in developmental instability, thereby affecting normal trait symmetry. The present study was designed to test this hypothesis by examining fluctuating dental asymmetry in an inbred strain of rabbits with familial, nonsyndromic Coronal craniosynostosis. The mesiodistal (MD) and buccolingual (BL) dimensions of the right and left maxillary first molars were measured in four groups of New Zealand white rabbits (N=176; n=40 with early-onset synostosis, n=65 with delayed-onset synostosis, n=46 in-colony, phenotypically normal rabbits, and n=25 wild-type normal controls). For each variable, raw signed asymmetry was calculated (left-right) and tested for assumptions of fluctuating asymmetry (i.e., normality and non-directionality). Any group that did not meet these assumptions was excluded from further analysis. Using a standard size-adjusted, fluctuating asymmetry index, mean fluctuating asymmetry was calculated and compared across groups with non-parametric statistics. For the MD dimension, no significant (p > 0.05) group differences in mean fluctuating asymmetry were observed among groups. In contrast, rabbits with early-onset synostosis had significantly (p < 0.05) more fluctuating asymmetry in the BL dimension compared to wild-type controls. Results demonstrate increased fluctuating dental asymmetry in rabbits with nonsyndromic, early-onset Coronal Suture synostosis and suggest that the molecular events producing Suture synostosis locally may have also have systemic effects. Knowledge of these systemic interactions may contribute to a fuller understanding of the phenotypic spectrum observed in individuals with nonsyndromic craniosynostosis.
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the influence of surgical correction on white matter microstructural integrity in rabbits with familial Coronal Suture craniosynostosis
Neurosurgical Focus, 2015Co-Authors: Christopher M Bonfield, Wendy Fellowsmayle, Lesley M Foley, S Kundu, T K Hitchens, G K Rohde, Ramesh Grandhi, Mark P MooneyAbstract:OBJECT Craniosynostosis is a condition in which one or more of the calvarial Sutures fuses prematurely. In addition to the cosmetic ramifications attributable to premature Suture fusion, aberrations in neurophysiological parameters are seen, which may result in more significant damage. This work examines the microstructural integrity of white matter, using diffusion tensor imaging (DTI) in a homogeneous strain of rabbits with simple, familial Coronal Suture synostosis before and after surgical correction. METHODS After diagnosis, rabbits were assigned to different groups: wild-type (WT), rabbits with early-onset complete fusion of the Coronal Suture (BC), and rabbits that had undergone surgical correction with Suturectomy (BC-SU) at 10 days of age. Fixed rabbit heads were imaged at 12, 25, or 42 days of life using a 4.7-T, 40-cm bore Avance scanner with a 7.2-cm radiofrequency coil. For DTI, a 3D spin echo sequence was used with a diffusion gradient (b = 2000 sec/mm2) applied in 6 directions. RESULTS As a...
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relaxin does not rescue Coronal Suture fusion in craniosynostotic rabbits
The Cleft Palate-Craniofacial Journal, 2012Co-Authors: James Cray, Michael I Siegel, Anne M Burrows, Gregory M Cooper, Lisa Vecchione, Christopher R Kinsella, Joseph E Losee, Amr M Moursi, Mark P MooneyAbstract:Objectives: Craniosynostosis affects 1 in 2000 to 3000 live births and may result in craniofacial and neural growth disturbances. Histological data have shown that thick collagenous bundles are present in the sutural ligament, which may tether the osteogenic fronts, resulting in premature fusion. The hormone relaxin has been shown to disrupt collagen fiber organization, possibly preventing craniosynostosis by relaxing the sutural ligament and allowing osteogenic fronts to separate normally and stay patent. This study tested this hypothesis with a rabbit model of delayed-onset Coronal Suture synostosis. Methods: A total of 18 New Zealand White rabbits with craniosynostosis were randomly assigned to one of three groups: sham control, protein control (BSA), relaxin treatment. After initial diagnosis, sham surgery, BSA, or relaxin was delivered to the fusing Coronal Suture in a slow-release (56-day) collagen vehicle. Longitudinal radiographs and body weights were collected at 10, 25, 42, and 84 days of age, a...
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Craniosacral therapy : The effects of cranial manipulation on intracranial pressure and cranial bone movement
Journal of Orthopaedic & Sports Physical Therapy, 2006Co-Authors: Patricia A. Downey, Michael I Siegel, Timothy Barbano, Rupali Kapur-wadhwa, James J. Sciote, Mark P MooneyAbstract:Study Design Quasi-experimental design. Objectives To determine if physical manipulation of the cranial vault Sutures will result in changes of the intracranial pressure (ICP) along with movement at the Coronal Suture. Background Craniosacral therapy is used to treat conditions ranging from headache pain to developmental disabilities. However, the biological premise for this technique has been theorized but not substantiated in the literature. Methods Thirteen adult New Zealand white rabbits (oryctolagus cuniculus) were anesthetized and microplates were attached on either side of the Coronal Suture. Epidural ICP measurements were made using a NeuroMonitor transducer. Distractive loads of 5, 10, 15, and 20 g (simulating a craniosacral frontal lift technique) were applied sequentially across the Coronal Suture. Baseline and distraction radiographs and ICP were obtained. One animal underwent additional distractive loads between 100 and 10 000 g. Plate separation was measured using a digital caliper from the ...
Timothy D Smith - One of the best experts on this subject based on the ideXlab platform.
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rescue of premature Coronal Suture fusion with tgf β2 neutralizing antibody in rabbits with delayed onset synostosis
The Cleft Palate-Craniofacial Journal, 2018Co-Authors: Mark P Mooney, Timothy D Smith, Anne M Burrows, Gregory M Cooper, James Cray, Jocelyn M Shand, John F Caccamese, James R GilbertAbstract:Objectives: An overexpression of Tgf-β2 leads to calvarial hyperostosis and Suture fusion in individuals with craniosynostosis. Inhibition of Tgf-β2 may help rescue fusing Sutures and restore normal growth. The present study was designed to test this hypothesis. Design: Twenty-eight New Zealand White rabbits with delayed-onset Coronal synostosis had radiopaque markers placed on either side of the Coronal Sutures at 10 days of age. The rabbits were randomly assigned to: (1) sham control rabbits (n = 10), (2) rabbits with control IgG (100 μg/Suture) delivered in a collagen vehicle (n = 9), and (3) rabbits with Tgf-β2 neutralizing antibody (100 μg/Suture) delivered in a collagen vehicle (n = 9). Longitudinal growth data were collected at 10, 25, 42, and 84 days of age. Sutures were harvested at 84 days of age for histomorphometry. Results: Radiographic analysis showed significantly greater (P < .05) Coronal Suture marker separation, craniofacial length, cranial vault length, height, shape indices, cranial...
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mandibular form in a rabbit model of familial nonsyndromic Coronal Suture synostosis
Journal of Craniofacial Surgery, 2002Co-Authors: Anne M Burrows, Theodore M Cole, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Michael I SiegelAbstract:Nonsyndromic Coronal Suture synostosis produces predictable and well-documented morphologies of the cranial vault with anteroposterior growth restrictions and mediolateral compensatory growth. The potential effects of nonsyndromic Coronal Suture synostosis on mandibular form are not as clear, however. This study was designed to evaluate whether Coronal Suture synostosis is associated with alterations in mandibular form by using a familial rabbit model of Coronal Suture synostosis. To assess this potential relation, the following hypothesis was tested: mandibular form in rabbits with Coronal Suture synostosis is significantly (P 0.05). In particular, distances involving the coronoid process in rabbits with Coronal Suture synostosis were significantly different, paralleling previous work in human patients with Coronal synostosis. There are no intrinsic condylar linear or shape differences between any of these groups, however. The form difference noted is most likely secondary to the synostosed Coronal Suture and may reflect alterations in the cranial base or masticatory musculature in this rabbit model.
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endocranial vascular patterns in a familial rabbit model of Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Valerie Dean Oloughlin, Michael I SiegelAbstract:Abstract Objective: The present study investigates the potential relationship between craniosynostosis and any changes in endocranial vasculature. The hypothesis that crania from rabbits with familial, nonsyndromic Coronal Suture synostosis and crania from rabbits with experimental immobilization of the Coronal Suture are associated with altered form of the middle meningeal vessels and dural venous sinuses is tested. Design: Silicone rubber endocasts from 14 adult New Zealand white rabbits (Oryctolagus cuniculus) with familial nonsyndromic Coronal Suture synostosis (five with bilateral Coronal Suture synostosis and nine with unilateral Coronal Suture synostosis) were made to assess middle meningeal vessel and dural venous sinus form. For comparative purposes, endocasts were made from 25 rabbits with normal, patent Coronal Sutures and 10 rabbits with experimental immobilization of the Coronal Suture. Impressions of the dural venous sinuses were assessed for depth and width. The area of the confluens of sin...
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correction of Coronal Suture synostosis using Suture and dura mater allografts in rabbits with familial craniosynostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Mark P Mooney, Anne M Burrows, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Lynne A Opperman, Amy M Kreithen, Rusen KapucuAbstract:Abstract Objective: Resynostosis following surgical correction of craniosynostosis is a common clinical correlate. Recent studies suggest that the dura mater is necessary to maintain Suture patency. It has also been hypothesized that dura mater from synostotic individuals may provide aberrant biochemical signals to the osteogenic fronts of the calvaria, which result in premature Suture fusion and subsequent resynostosis following surgery. This study was designed to test this hypothesis by surgically manipulating the Coronal Suture and dura mater in rabbits with familial craniosynostosis to prevent postsurgical resynostosis. Design: Craniofacial growth and histomorphometric data were collected from 129 rabbits: 72 normal controls and 57 rabbits with bilateral Coronal Suture synostosis (15 unoperated on controls; 13 surgical controls; 9 dura mater transplant only; 10 Suture transplant only; and 10 Suture and dura mater transplant). At 10 days of age, all rabbits had radiopaque amalgam markers placed on eith...
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age related changes in intracranial pressure in rabbits with uncorrected familial Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2000Co-Authors: Wendy Fellowsmayle, Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Gregory M Cooper, Ian F Pollack, Michael I SiegelAbstract:Abstract Objective: Chronic, elevated intracranial pressure (ICP) in craniosynostotic infants may result in ocular and neurocapsular problems; however, not all infants exhibit elevated ICP. Clinical ICP studies are further confounded by small and heterogeneic samples, multiple-Suture involvement, and varying surgical management protocols. The present study was designed to describe longitudinal changes in ICP in a large, homogenous sample of rabbits with uncorrected familial, nonsyndromic Coronal Suture synostosis. Methods: Ninety-one rabbits were divided into four groups: (1) normal rabbits (n = 28), (2) rabbits with delayed-onset Coronal Suture synostosis (DOCS; n = 25), (3) rabbits with unilateral Coronal Suture synostosis (UCS; n = 12), and (4) rabbits with bilateral Coronal Suture synostosis (BCS; n = 26). ICP was measured at 24 and 42 days of age using a Codman epidural microtransducer. Results: Rabbits with BCS had a significantly (p < .05) higher mean ICP at 25 days of age than rabbits in the other...
Anne M Burrows - One of the best experts on this subject based on the ideXlab platform.
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mandibular form in a rabbit model of familial nonsyndromic Coronal Suture synostosis
Journal of Craniofacial Surgery, 2002Co-Authors: Anne M Burrows, Theodore M Cole, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Michael I SiegelAbstract:Nonsyndromic Coronal Suture synostosis produces predictable and well-documented morphologies of the cranial vault with anteroposterior growth restrictions and mediolateral compensatory growth. The potential effects of nonsyndromic Coronal Suture synostosis on mandibular form are not as clear, however. This study was designed to evaluate whether Coronal Suture synostosis is associated with alterations in mandibular form by using a familial rabbit model of Coronal Suture synostosis. To assess this potential relation, the following hypothesis was tested: mandibular form in rabbits with Coronal Suture synostosis is significantly (P 0.05). In particular, distances involving the coronoid process in rabbits with Coronal Suture synostosis were significantly different, paralleling previous work in human patients with Coronal synostosis. There are no intrinsic condylar linear or shape differences between any of these groups, however. The form difference noted is most likely secondary to the synostosed Coronal Suture and may reflect alterations in the cranial base or masticatory musculature in this rabbit model.
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endocranial vascular patterns in a familial rabbit model of Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Valerie Dean Oloughlin, Michael I SiegelAbstract:Abstract Objective: The present study investigates the potential relationship between craniosynostosis and any changes in endocranial vasculature. The hypothesis that crania from rabbits with familial, nonsyndromic Coronal Suture synostosis and crania from rabbits with experimental immobilization of the Coronal Suture are associated with altered form of the middle meningeal vessels and dural venous sinuses is tested. Design: Silicone rubber endocasts from 14 adult New Zealand white rabbits (Oryctolagus cuniculus) with familial nonsyndromic Coronal Suture synostosis (five with bilateral Coronal Suture synostosis and nine with unilateral Coronal Suture synostosis) were made to assess middle meningeal vessel and dural venous sinus form. For comparative purposes, endocasts were made from 25 rabbits with normal, patent Coronal Sutures and 10 rabbits with experimental immobilization of the Coronal Suture. Impressions of the dural venous sinuses were assessed for depth and width. The area of the confluens of sin...
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correction of Coronal Suture synostosis using Suture and dura mater allografts in rabbits with familial craniosynostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Mark P Mooney, Anne M Burrows, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Lynne A Opperman, Amy M Kreithen, Rusen KapucuAbstract:Abstract Objective: Resynostosis following surgical correction of craniosynostosis is a common clinical correlate. Recent studies suggest that the dura mater is necessary to maintain Suture patency. It has also been hypothesized that dura mater from synostotic individuals may provide aberrant biochemical signals to the osteogenic fronts of the calvaria, which result in premature Suture fusion and subsequent resynostosis following surgery. This study was designed to test this hypothesis by surgically manipulating the Coronal Suture and dura mater in rabbits with familial craniosynostosis to prevent postsurgical resynostosis. Design: Craniofacial growth and histomorphometric data were collected from 129 rabbits: 72 normal controls and 57 rabbits with bilateral Coronal Suture synostosis (15 unoperated on controls; 13 surgical controls; 9 dura mater transplant only; 10 Suture transplant only; and 10 Suture and dura mater transplant). At 10 days of age, all rabbits had radiopaque amalgam markers placed on eith...
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age related changes in intracranial pressure in rabbits with uncorrected familial Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2000Co-Authors: Wendy Fellowsmayle, Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Gregory M Cooper, Ian F Pollack, Michael I SiegelAbstract:Abstract Objective: Chronic, elevated intracranial pressure (ICP) in craniosynostotic infants may result in ocular and neurocapsular problems; however, not all infants exhibit elevated ICP. Clinical ICP studies are further confounded by small and heterogeneic samples, multiple-Suture involvement, and varying surgical management protocols. The present study was designed to describe longitudinal changes in ICP in a large, homogenous sample of rabbits with uncorrected familial, nonsyndromic Coronal Suture synostosis. Methods: Ninety-one rabbits were divided into four groups: (1) normal rabbits (n = 28), (2) rabbits with delayed-onset Coronal Suture synostosis (DOCS; n = 25), (3) rabbits with unilateral Coronal Suture synostosis (UCS; n = 12), and (4) rabbits with bilateral Coronal Suture synostosis (BCS; n = 26). ICP was measured at 24 and 42 days of age using a Codman epidural microtransducer. Results: Rabbits with BCS had a significantly (p < .05) higher mean ICP at 25 days of age than rabbits in the other...
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three dimensional analysis of craniofacial form in a familial rabbit model of nonsyndromic Coronal Suture synostosis using euclidean distance matrix analysis
The Cleft Palate-Craniofacial Journal, 1999Co-Authors: Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Joan T Richtsmeier, Michael I SiegelAbstract:Abstract Objective: Simple craniosynostoses produce predictable morphologies of the cranial vault, with growth deficits in a direction parallel to the synostosed Suture and compensatory growth at Sutures that are perpendicular to and attached to the synostosed one. In Coronal Suture synostosis, antero posterior growth is inhibited, with compensatory growth in a transverse direction. Information on growth patterns and influence on other craniofacial regions are not as clear. This study tested the hypotheses that (1), both juvenile and adult rabbits with familial, nonsyndromic Coronal Suture synostosis exhibit significant size and shape differences of the entire craniofacial region relative to normal rabbits as a result of altered growth patterns and that (2), shape differences of the calvaria will precede those of the basicranium. Design: Fifty anatomic landmarks were located on 94 New Zealand white rabbit crania. The crania were divided into a juvenile, six-week-old age category (n = 53) and an adult, 18-...
Wolfgang H Losken - One of the best experts on this subject based on the ideXlab platform.
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rescue of Coronal Suture fusion using transforming growth factor beta 3 tgf β3 in rabbits with delayed onset craniosynostosis
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2003Co-Authors: Sherri L Y N Chong, Wolfgang H Losken, Amr M Moursi, Ronal Mitchell, Phillip L Winnard, James P Bradley, Omer R Ozerdem, Kodi K Azari, Oguz AcarturkAbstract:Craniosynostosis results in cranial deformities and increased intracranial pressure, which pose extensive and recurrent surgical management problems. Developmental studies in rodents have shown that low levels of transforming growth factor-β3 (Tgf-β3) are associated with normal fusion of the interfrontal (IF) Suture, and that Tgf-β3 prevents IF Suture fusion in a dose-dependent fashion. The present study was designed to test the hypothesis that Tgf-β3 can also prevent or “rescue” fusing Sutures in a rabbit model with familial craniosynostosis. One hundred Coronal Sutures from 50 rabbits with delayed-onset, Coronal Suture synostosis were examined in the present study. The rabbits were divided into five groups of 10 rabbits each: 1) sham controls, 2) bovine serum albumin (BSA, 500 ng) low-dose protein controls, 3) low-dose Tgf-β3 (500 ng), 4) high-dose BSA (1,000 ng) controls, and 5) high-dose Tgf-β3 (1,000 ng). At 10 days of age, radiopaque amalgam markers were implanted in all of the rabbits on either side of the Coronal Suture to monitor sutural growth. At 25 days of age, the BSA or Tgf-β3 was combined with a slow-absorbing collagen vehicle and injected subperiosteally above the Coronal Suture. Radiographic results revealed that high-dose Tgf-β3 rabbits had significantly greater (P < 0.05) Coronal Suture marker separation than the other groups. Histomorphometric analysis revealed that high-dose Tgf-β3 rabbits also had patent Coronal Sutures and significantly (P < 0.01) greater sutural widths and areas than the other groups. The results suggest that there is a dose-dependent effect of TGF-β3 on Suture morphology and area in these rabbits, and that the manipulation of such growth factors may have clinical applications in the treatment of craniosynostosis. Anat Rec Part A 274A:962–971, 2003. © 2003 Wiley-Liss, Inc.
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mandibular form in a rabbit model of familial nonsyndromic Coronal Suture synostosis
Journal of Craniofacial Surgery, 2002Co-Authors: Anne M Burrows, Theodore M Cole, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Michael I SiegelAbstract:Nonsyndromic Coronal Suture synostosis produces predictable and well-documented morphologies of the cranial vault with anteroposterior growth restrictions and mediolateral compensatory growth. The potential effects of nonsyndromic Coronal Suture synostosis on mandibular form are not as clear, however. This study was designed to evaluate whether Coronal Suture synostosis is associated with alterations in mandibular form by using a familial rabbit model of Coronal Suture synostosis. To assess this potential relation, the following hypothesis was tested: mandibular form in rabbits with Coronal Suture synostosis is significantly (P 0.05). In particular, distances involving the coronoid process in rabbits with Coronal Suture synostosis were significantly different, paralleling previous work in human patients with Coronal synostosis. There are no intrinsic condylar linear or shape differences between any of these groups, however. The form difference noted is most likely secondary to the synostosed Coronal Suture and may reflect alterations in the cranial base or masticatory musculature in this rabbit model.
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endocranial vascular patterns in a familial rabbit model of Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Valerie Dean Oloughlin, Michael I SiegelAbstract:Abstract Objective: The present study investigates the potential relationship between craniosynostosis and any changes in endocranial vasculature. The hypothesis that crania from rabbits with familial, nonsyndromic Coronal Suture synostosis and crania from rabbits with experimental immobilization of the Coronal Suture are associated with altered form of the middle meningeal vessels and dural venous sinuses is tested. Design: Silicone rubber endocasts from 14 adult New Zealand white rabbits (Oryctolagus cuniculus) with familial nonsyndromic Coronal Suture synostosis (five with bilateral Coronal Suture synostosis and nine with unilateral Coronal Suture synostosis) were made to assess middle meningeal vessel and dural venous sinus form. For comparative purposes, endocasts were made from 25 rabbits with normal, patent Coronal Sutures and 10 rabbits with experimental immobilization of the Coronal Suture. Impressions of the dural venous sinuses were assessed for depth and width. The area of the confluens of sin...
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correction of Coronal Suture synostosis using Suture and dura mater allografts in rabbits with familial craniosynostosis
The Cleft Palate-Craniofacial Journal, 2001Co-Authors: Mark P Mooney, Anne M Burrows, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Lynne A Opperman, Amy M Kreithen, Rusen KapucuAbstract:Abstract Objective: Resynostosis following surgical correction of craniosynostosis is a common clinical correlate. Recent studies suggest that the dura mater is necessary to maintain Suture patency. It has also been hypothesized that dura mater from synostotic individuals may provide aberrant biochemical signals to the osteogenic fronts of the calvaria, which result in premature Suture fusion and subsequent resynostosis following surgery. This study was designed to test this hypothesis by surgically manipulating the Coronal Suture and dura mater in rabbits with familial craniosynostosis to prevent postsurgical resynostosis. Design: Craniofacial growth and histomorphometric data were collected from 129 rabbits: 72 normal controls and 57 rabbits with bilateral Coronal Suture synostosis (15 unoperated on controls; 13 surgical controls; 9 dura mater transplant only; 10 Suture transplant only; and 10 Suture and dura mater transplant). At 10 days of age, all rabbits had radiopaque amalgam markers placed on eith...
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age related changes in intracranial pressure in rabbits with uncorrected familial Coronal Suture synostosis
The Cleft Palate-Craniofacial Journal, 2000Co-Authors: Wendy Fellowsmayle, Anne M Burrows, Mark P Mooney, Timothy D Smith, Wolfgang H Losken, Jason Dechant, Gregory M Cooper, Ian F Pollack, Michael I SiegelAbstract:Abstract Objective: Chronic, elevated intracranial pressure (ICP) in craniosynostotic infants may result in ocular and neurocapsular problems; however, not all infants exhibit elevated ICP. Clinical ICP studies are further confounded by small and heterogeneic samples, multiple-Suture involvement, and varying surgical management protocols. The present study was designed to describe longitudinal changes in ICP in a large, homogenous sample of rabbits with uncorrected familial, nonsyndromic Coronal Suture synostosis. Methods: Ninety-one rabbits were divided into four groups: (1) normal rabbits (n = 28), (2) rabbits with delayed-onset Coronal Suture synostosis (DOCS; n = 25), (3) rabbits with unilateral Coronal Suture synostosis (UCS; n = 12), and (4) rabbits with bilateral Coronal Suture synostosis (BCS; n = 26). ICP was measured at 24 and 42 days of age using a Codman epidural microtransducer. Results: Rabbits with BCS had a significantly (p < .05) higher mean ICP at 25 days of age than rabbits in the other...