Encephalocele as a complication post-craniosynostosis surgery.

Duraplasty is one of the most common neurosurgical procedures which complications include iatrogenic pseudomeningocele, which is common, but ossification of pseudomeningocele following cranial surgery is a rare event. We present a case of a 2-year-old male patient who came to our hospital with a huge bulge in his head and weakness in the right arm and leg. He had a history of sagittal craniosynostosis with a postoperative cranioplasty complication of left parital pseudomeningocele. He underwent a duraplasty, but the bulge recurred with failed cerebrospinal fluid aspiration and external ventricular drain, changing in size periodically. Computed tomography showed that the bulge was a median and left paramedian parital encephalocele, so encephalocele with ossification was diagnosed and a cranioplasty was done. This case highlights that iatrogenic encephaloceles with ossification can develop after duraplasty repair in the parital region. Also, if a postoperative pseudomeningocele changes in size or consistency, clinicians should look for ossification.

Homing and efficacy of intra-articular injection of autologous mesenchymal stem cells in experimental chondral defects in dogs.

OBJECTIVES: This study was intended to verify the likelihood of homing of intra-articularily injected mesenchymal stem cells (MSCs) and its involvement in the healing process of experimentally induced, acute and chronic, partial chondral defects in dogs. METHODS: Partial thickness chondral defects were created on the lateral femoral condyle of stifle joint in domestic mongrel dogs. MSCs were harvested in a separate procedure, labelled with green fluorescent protein (GFP) using monster GFP vector and suspended in buffer phosphate solution for intra-articular (IA) injection. Dogs were divided into three groups. Group I, served as the control. The dogs in the two cell-treated groups received a single IA injection of MSCs one day (Group II) and one month (Group III) after creating the defect. Sacrifice was scheduled at 2 and 8 weeks post-surgery for group I, and 2 and 8 weeks post-treatment, for the cell-treated groups. Morphological, histological, and fluorescence analysis was performed. RESULTS: Recovery was significant both clinically and histologically in the two cell-treated groups (Group II and III) compared to the control (Group I), (p<0.001). In the meantime, Group-II showed better results at 8 weeks than Group III (p=0.01). Homing was confirmed by the incorporation of injected GFP-labelled MSCs within the newly formed cartilage. CONCLUSIONS: The obtained results prove that the use of IA injection of autologous MSCs is a viable option for treating partial cartilage defects. Cell labelling gave evidence to the certainty of cell homing within the neocartilage of all treated cases and the participation in the reparative process.

Computation of a tetrahedral mesh for striated muscle deformation simulation.

Competing concepts exist regarding surgery for instance of the cleft lip and palate to date. Morphology-based simulations at histological scale may one day be used to help the surgeon predict the possible outcome of a variety of approaches. It however can be a challenge to generate volume meshes that are applicable to the mathematical modelling of three-dimensional spatial modifications. Computation of surface meshes may be considered less delicate. The aim of this study is to design and evaluate a novel algorithm that supports finite element methods. Images of histological serial sections of a striated muscle were segmented. Results of the three-dimensional reconstruction of multiple layers of the polygonal segmentation data characterized the hull of the muscle. The corresponding surface mesh was then converted into a tetrahedral mesh to generate volume. This was achieved by mapping multiple template types onto neighbouring intersection polygons. Muscle contraction was subsequently simulated by mesh deformation. The technique successfully generated volumes and was able to provide data on contraction directions. The mesh supported a novel approach to simulate representations of contraction. However, several drawbacks were evident. Mathematical modelling of scenarios with more than one striated muscle will require considerable modification of the currently presented approach. Future studies need to then evaluate the applicability of volume meshes to represent arrays of three-dimensional biological objects. Surface mesh based mathematical modelling of cleft lip and palate surgery and its results are therefore not yet in reach.