Traditional Versus Virtual Surgery Planning of the Fronto-Orbital Unit in Anterior Cranial Vault Remodeling Surgery

Application of Computerized Surgical Planning in Craniosynostosis Surgery

Craniosynostosis, a medical condition characterized by premature fusion of one or multiple cranial sutures, has historically been treated through surgical correction. Computerized Surgical Planning (CSP) and three-dimensional (3D) modeling have gained significant popularity across craniofacial surgery. Through a collaborative effort between surgeons and engineers, it is now possible to virtually execute a surgical plan based on preoperative imaging using computed tomography scans. The CSP workflow involves several elements including virtual 3D modeling, CSP computer-aided surgical guide design, manufacturing of guides and templates, and intraoperative implementation. Through the gradual optimization of this workflow, it has been possible to achieve significant progress in the surgical process including improvements in the preoperative planning of complex craniosynostosis cases and reduction of intraoperative time. Furthermore, CSP and 3D modeling have had a positive impact on surgical simulation and residency training, along with patient education and counseling. This article summarizes the CSP workflow in the treatment of craniosynostosis and the implications of this treatment modality on medical trainee education and patient management.

The Role of Virtual Surgical Planning in Surgery for Complex Craniosynostosis

Background

Virtual surgical planning (VSP) decreases reliance on intraoperative subjective assessment of aesthetic and functional outcomes in craniofacial surgery. Here, we describe our experience of using VSP for complex craniosynostosis surgery to inform preoperative decision making and optimize postoperative outcomes.

Methods

Chart review was performed for children treated with craniosynostosis at our institution from 2015 to 2021. Eight VSP maneuvers were defined and assigned to each patient when applicable: (1) complex cranioplasty: combined autologous and synthetic; (2) autologous cranioplasty; (3) synthetic cranioplasty; (4) vector analysis and distractor placement; (5) complex osteotomies; (6) multilayered intraoperative plans; (7) volume analysis; and (8) communication with parents. Outcomes between VSP and non-VSP cohorts were compared.

Results

Of 166 total cases, 32 were considered complex, defined by multisutural craniosynostosis, syndromic craniosynostosis, or revision status. Of these complex cases, 20 underwent VSP and 12 did not. There was no difference in mean operative time between the VSP and non-VSP groups (541 versus 532 min, P = 0.82) or in unexpected return to operating room (10.5% versus 8.3%, P = 0.84). VSP was most often used to communicate the surgical plan with parents (90%) and plan complex osteotomies (85%).

Conclusions

In this cohort, VSP was most often used to communicate the surgical plan with families and plan complex osteotomies. Our results indicate that VSP may improve intraoperative efficiency and safety for complex craniosynostosis surgery. This tool can be considered a useful adjunct to plan and guide intraoperative decisions in complex cases, reducing variability and guiding parental expectations.

Virtual Surgical Planning in Craniosynostosis Reduces Operative Time and Length of Stay for Cranial Vault Remodeling

Cranial vault remodeling (CVR) with and without frontal orbital advancement remodels the skull in craniosynostosis. Virtual surgical planning (VSP) for preoperative planning has been previously shown to be effective in CVR. In this study, the authors aimed to evaluate the impact of VSP on operative and perioperative efficiency for craniosynostosis surgery. A retrospective chart review was conducted of patients with craniosynostosis who underwent CVR. Patient demographics, perioperative variables, use of VSP, and complications were obtained. Perioperative variables collected include operative time and length of stay. An independent t test was used to compare variables from patients who had surgery with VSP and patients who did not. Records were available for 126 patients with craniosynostosis who underwent CVR of whom 79 (62.7%) utilized VSP. There was no difference in average age at surgery (9.3±5.7 mo versus 13.2±31.1 mo, P =0.39). Surgeries planned using VSP demonstrated a decreased operative time of 1.3 hours (3.7±1.1 versus 5.0±1.1 h, P <0.001) and a shorter length of stay (3.9±1.3 versus 4.6±1.7 d, P =0.01). There were no differences in complication rates of dehiscence, infection, returns to the operating room, or 30-day readmission. These trends were similar among patients who underwent fronto-orbital advancement in addition to CVR. Virtual surgical planning was associated with decreased operative time and length of stay for patients with craniosynostosis and comparable complication rates. Virtual surgical planning is an effective tool for reducing anesthetic exposure time.

Elevated Intracranial Pressure After Primary Surgical Correction of Sagittal Suture Craniosynostosis

Study Design: A Case Report. Objective: Craniosynostosis is a craniofacial condition defined by premature fusion of at least one cranial suture. Resynostosis or secondary craniosynostosis of a previously patent adjacent suture following primary repair is a relatively common complication. While studies have assessed the rates of secondary craniosynostosis and subsequent reoperation, extremely limited data regarding reoperation techniques is available. Methods: We present a unique case of a pediatric patient with sagittal craniosynostosis who previously underwent a modified pi procedure and later developed resynostosis of the sagittal suture and secondary synostosis of the bicoronal sutures. We subsequently performed total cranial vault reconstruction with virtual surgical planning (VSP). Results: At his 31-month postoperative follow-up, he displayed normal head shape and denied any clinical signs of elevated intracranial pressures with a normal ophthalmological exam. Conclusions: The reoperation was successful with no significant postoperative complications noted. Performing geometric expansion with VSP to manage fusion of a previously open suture following primary treatment of sagittal synostosis should be considered within the armamentarium of operative options.

The need for overcorrection: evaluation of computer-assisted, virtually planned, fronto-orbital advancement using postoperative 3D photography

OBJECTIVE

The main indication for craniofacial remodeling of craniosynostosis is to correct the deformity, but potential increased intracranial pressure resulting in neurocognitive damage and neuropsychological disadvantages cannot be neglected. The relapse rate after fronto-orbital advancement (FOA) seems to be high; however, to date, objective measurement techniques do not exist. The aim of this study was to quantify the outcome of FOA using computer-assisted design (CAD) and computer-assisted manufacturing (CAM) to create individualized 3D-printed templates for correction of craniosynostosis, using postoperative 3D photographic head and face surface scans during follow-up.

METHODS

The authors included all patients who underwent FOA between 2014 and 2020 with individualized, CAD/CAM-based, 3D-printed templates and received postoperative 3D photographic face and head scans at follow-up. Since 2016, the authors have routinely planned an additional "overcorrection" of 3 mm to the CAD-based FOA correction of the affected side(s). The virtually planned supraorbital angle for FOA correction was compared with the postoperative supraorbital angle measured on postoperative 3D photographic head and face surface scans. The primary outcome was the delta between the planned CAD/CAM FOA correction and that achieved based on 3D photographs. Secondary outcomes included outcomes with and those without "overcorrection," time of surgery, blood loss, and morbidity.

RESULTS

Short-term follow-up (mean 9 months after surgery; 14 patients) showed a delta of 12° between the planned and achieved supraorbital angle. Long-term follow-up (mean 23 months; 8 patients) showed stagnant supraorbital angles without a significant increase in relapse. Postsurgical supraorbital angles after an additionally planned overcorrection (of 3 mm) of the affected side showed a mean delta of 11° versus 14° without overcorrection. The perioperative and postoperative complication rates of the whole cohort (n = 36) were very low, and the mean (SD) intraoperative blood loss was 128 (60) ml with a mean (SD) transfused red blood cell volume of 133 (67) ml.

CONCLUSIONS

Postoperative measurement of the applied FOA on 3D photographs is a feasible and objective method for assessment of surgical results. The delta between the FOA correction planned with CAD/CAM and the achieved correction can be analyzed on postoperative 3D photographs. In the future, calculation of the amount of "overcorrection" needed to avoid relapse of the affected side(s) after FOA may be possible with the aid of these techniques.