Statistical shape analyses of trigonocephaly patients

Statistical shape analyses of corpus callosum changes at preoperative and postoperative scaphocephaly patients

PURPOSE

Scaphocephaly is the premature closure of the sagittal suture. The treatment strategies mainly focus on correcting the shape of the head, but there are very limited studies examining changes in brain structure. This study aimed to investigate shape differences in the shape of corpus callosum regarding the pre-treatment and post-treatment term at scaphocephaly patients.

METHODS

Cranium shape data were collected from the two-dimensional digital images. The generalized Procrustes analysis was used to obtain mean shapes in the pre- and postoperative phases. The shape deformation of the corpus callosum from the pre- to postoperative phases was evaluated using the thin plate spline method.

RESULTS

There is an enlargement of the splenium part of corpus callosum in the late group. In the early group, corpus callosum genu and body enlargement were observed in the postoperative period compared to the preoperative period, followed by a narrowing of the isthmus region.

CONCLUSION

This study showed structural deformations in the corpus callosum in scaphocephaly patients using head shape with the landmark-based geometric morphometric method by taking into consideration the topographic distribution. An enlargement at the splenium part of corpus callosum exposes after the cranial vault expansion depending on time.

Anthropometric cranial measurements in metopic craniosynostosis/trigonocephaly: diagnostic criteria, classification of severity and indications for surgery

ABSTRACT

Metopic craniosynostosis is the second most frequent type of craniosynostosis. When the phenotypic presentation has been deemed severe the treatment is surgical in nature and is performed in infancy with fronto-orbital advancement and cranial vault remodeling. At the time of this writing, there is no consensus regarding an objective evaluation system for severity, diagnostic criteria, or indications for surgery. This study aims to review the anthropometric cranial measurements and the relative diagnostic criteria/classification of severity/surgical indications proposed so far for this skull malformation, and to investigate if there is any scientific support for their utility.

Augmented reality and physical hybrid model simulation for preoperative planning of metopic craniosynostosis surgery

OBJECTIVE

The main objective of neurosurgery is to establish safe and reliable surgical techniques. Medical technology has advanced during the 21st century, enabling the development of increasingly sophisticated tools for preoperative study that can be used by surgeons before performing surgery on an actual patient. Laser-printed models are a robust tool for improving surgical performance, planning an operative approach, and developing the skills and strategy to deal with uncommon and high-risk intraoperative difficulties. Practice with these models enhances the surgeon’s understanding of 3D anatomy but has some limitations with regard to tactile perception. In this study, the authors aimed to develop a preoperative planning method that combines a hybrid model with augmented reality (AR) to enhance preparation for and planning of a specific surgical procedure, correction of metopic craniosynostosis, also known as trigonocephaly.

METHODS

With the use of imaging data of an actual case patient who underwent surgical correction of metopic craniosynostosis, a physical hybrid model (for hands-on applications) and an AR app for a mobile device were created. The hybrid customized model was developed by using analysis of diagnostic CT imaging of a case patient with metopic craniosynostosis. Created from many different types of silicone, the physical model simulates anatomical conditions, allowing a multidisciplinary team to deal with different situations and to precisely determine the appropriate surgical approach. A real-time AR interface with the physical model was developed by using an AR app that enhances the anatomic aspects of the patient’s skull. This method was used by 38 experienced surgeons (craniofacial plastic surgeons and neurosurgeons), who then responded to a questionnaire that evaluated the realism and utility of the hybrid AR simulation used in this method as a beneficial educational tool for teaching and preoperative planning in performing surgical metopic craniosynostosis correction.

RESULTS

The authors developed a practice model for planning the surgical cranial remodeling used in the correction of metopic craniosynostosis. In the hybrid AR model, all aspects of the surgical procedure previously performed on the case patient were simulated: subcutaneous and subperiosteal dissection, skin incision, and skull remodeling with absorbable miniplates. The pre- and postoperative procedures were also carried out, which emphasizes the role of the AR app in the hybrid model. On the basis of the questionnaire, the hybrid AR tool was approved by the senior surgery team and considered adequate for educational purposes. Statistical analysis of the questionnaire responses also highlighted the potential for the use of the hybrid model in future applications.

CONCLUSIONS

This new preoperative platform that combines physical and virtual models may represent an important method to improve multidisciplinary discussion in addition to being a powerful teaching tool. The hybrid model associated with the AR app provided an effective training environment, and it enhanced the teaching of surgical anatomy and operative strategies in a challenging neurosurgical procedure.