Perioperative Outcomes of Secondary Frontal Orbital Advancement After Posterior Vault Distraction Osteogenesis:

Long-term results of fronto-orbital advancement and remodeling using distraction osteogenesis in craniosynostosis patients

In the initial report describing the fronto-orbital distraction technique, bone segments were advanced preserving their attachments with the dura. This approach does not allow for the remodeling of the frontal segment. However, in the technique described herein, the fronto-orbital segment is separated from dura, remodeled, and advanced as a bone graft using distractors. Twenty-seven craniosynostosis patients that underwent fronto-orbital advancement and remodeling using distraction osteogenesis were retrospectively reviewed. The mean age at the time of surgery was 19.03 ± 9.19 months; the mean follow-up was 86.04 ± 34.98 months. The mean distraction amount was over 19 mm. No significant difference was found between frontal and occipital bone density measurements at the cortex and medulla. The mean total defect area was 4.79 ± 4.43 cm2 and the mean number of bone defects was 4.8 ± 2.2. The cephalic index decreased from 98.56 ± 6.39 to 87.63 ± 4.54, and 59.3% of the patients reached the normal range in the late postoperative period. Fronto-orbital advancement and remodeling using distraction osteogenesis appears to be safe and effective. Distraction of the frontal bone as a graft does not lead to bone resorption, and new bone formation and improvements in head shape can be achieved.

Evaluation of Complications and Outcomes in Craniosynostosis by Age of Operation: Analysis of the National Surgical Quality Improvement Program-Pediatric

Considerable controversy exists around the optimal age on which to operate for craniosynostosis. This study aims to use data from the American College of Surgeons National Surgical Quality Improvement Program-Pediatric to assess the impact of operative age on hospital stay and outcomes. After excluding patients who underwent endoscopic cranial vault remodeling, a total of 3292 patients met inclusion criteria in the National Surgical Quality Improvement Program-Pediatric between 2012 and 2019. Median age at surgery was 300 days (interquartile range: 204-494). Patients between 0 and 6 months underwent the highest proportion of complex cranial vault remodeling, Current Procedural Terminology 61,558 ( n =44, 7.7%) and Current Procedural Terminology 61,559 ( n =317, 55.1%). White blood cell counts peaked in the 12 to 18 months group, and were lowest in the 24± months group. Hematocrit was lowest in the 0 to 6 months group and rose steadily to the 24± months group; the inverse pattern was found in platelet concentration, which was highest in the youngest patients and lowest in the oldest. Prothrombin time, international normalized ratio, and partial thromboplastin time were relatively consistent across all age groups. Younger patients had significantly shorter operating room times, which increased with patient age ( P <0.001). Younger patients also had significantly shorter length of stay ( P =0.009), though length of stay peaked between 12 and 18 months. There was a significantly lower rate of surgical site infection in younger patients, which occurred in 0.7% of patients 0 to 12 months and 1.0 to 3.0% in patients over 12 to 24± months. There was no significant difference in the average number of transfusions required in any age group ( P =0.961).

Perioperative Morbidity of Secondary Frontal Orbital Advancement After Initial Frontal Orbital Advancement

Frontal orbital advancement (FOA) is frequently performed for patients with syndromic and/or multisuture craniosynostosis. A small proportion of patients who undergo FOA have unfavorable growth and subsequently require a second FOA later in life; however, the perioperative risks associated with this second procedure are not well studied. We report results from a retrospective review of FOAs conducted from 2007 to 2022 at a single site with the same craniofacial surgeon. A total of 33 patients were included. Perioperative outcomes were compared between primary and secondary FOA procedures. The two groups were similar in regard to suture involvement and diagnosis, although the secondary FOA group was older at the time of their FOA (1.23 versus 7.07 y, P <0.001). There was no significant difference between groups in operating time, volume of blood transfusion by weight, or in the incidence of postoperative wound complications ( P >0.05). Primary FOA procedures had significantly higher weight-adjusted blood loss (28 versus 18 mL/kg, P =0.014), with a higher proportion of patients receiving a blood transfusion (95% versus 62%, P =0.025). There was no significant difference between groups in the incidence of intraoperative dural injury (50% versus 84%, P =0.067). Our findings suggest that secondary procedures appear to impose less of a surgical risk relative to primary FOA traditionally performed in infancy, likely because of the advanced age at the time of secondary FOA.

Posterior vault distraction osteogenesis: indications and expectations

Cranial vault remodeling (CVR) in patients with craniosynostosis serves to correct abnormal skull morphology and increase intracranial volume to prevent or treat pathologic increases in intracranial pressure (Taylor and Bartlett, Plast Reconstr Surg 140: 82e-93e, 2017). Distraction osteogenesis is a well-established technique for bony repositioning and growth stimulation in the facial and long bones, in which the gradual separation of bony segments at an osteotomy site results in generation of new bone and subsequent bone lengthening (Greene, 2018). While initially described in the orthopedic literature, the relevance and applicability of distraction osteogenesis to craniofacial surgery has been well-studied and is now well-established (Steinbacher et al., Plast Reconstr Surg 127: 792-801, 2011). Posterior cranial vault distraction osteogenesis (PVDO) was introduced as a treatment option for cranial vault expansion in patients with craniosynostosis in 2009 by White et al., based upon the premise that posterior vault distraction could provide greater intracranial volume expansion than fronto-orbital advancement and remodeling (FOAR), but that acute posterior cranial vault expansions were limited by the soft tissue envelope of the infant scalp and prone to relapse related to the supine positioning typical of infants (White et al., Childs Nerv Syst 25: 231-236, 2009). Since this introduction, significant evidence has accrued regarding the safety of, and outcomes after, PVDO. PVDO is now known to provide larger increases in intracranial volume in comparison to anterior cranial vault remodeling procedures (Derderian et al., Plast Reconstr Surg 135:1665-1672, 2015) and to provide morphologic improvements in both the posterior and anterior cranial vaults (Goldstein et al., Plast Reconstr Surg 131:1367-1375, 2013). Perioperative major morbidity is comparable to conventional vault remodeling (Taylor et al., Plast Reconstr Surg 129:674e-680e, 2012) and the procedure has been safely applied to patients of various ages with syndromic and non-syndromic craniosynostosis (Zhang et al., J Craniofac Surg 29:566-571, 2018; Li et al., J Craniofac Surg 27:1165-1169, 2016). Many high-volume craniofacial centers now consider PVDO the preferred first operation in infants with syndromic craniosynostosis, and indications for this procedure continue to expand as evidence accrues regarding its utility and safety (Steinbacher et al., Plast Reconstr Surg 127: 792-801, 2011; Swanson et al., Plast Reconstr Surg 137:829e-841e, 2016).

Distraction osteogenesis in craniosynostosis

PURPOSE OF REVIEW

Craniosynostosis, a condition of premature cranial suture fusion, can have significantly detrimental effects on development and growth due to sequelae of increased intracranial hypertension (ICP), exophthalmos, and upper airway obstruction. Evolving surgical treatments now include distraction osteogenesis (DO) due to its many benefits relative to standard cranial vault remodeling procedures. This article provides an overview and update of different surgical applications of DO for patients with craniosynostosis.

RECENT FINDINGS

DO has been utilized successfully for single and multisuture craniosynostosis with or without midface hypoplasia to increase intracranial volume, decrease ICP and improve aesthetics. It has been applied in single suture synostosis, posterior vault DO, fronto-orbital advancement, monobloc DO and Le Fort III DO. DO has been applied through modification of traditional surgical procedures with success in maintaining goals of surgery while reducing risk.

SUMMARY

DO is still a relatively new and evolving surgical technique for patients with syndromic and nonsyndromic craniosynostosis. With promising benefits, consideration for each procedure should be weighed until longer-term data is available.

Craniosynostosis: Posterior Cranial Vault Remodeling

Posterior cranial vault distraction osteogenesis is a powerful, reliable, low-morbidity method to achieve intracranial expansion. It is particularly useful in treating turribrachycephaly seen in syndromic craniosynostosis, allowing for gradual expansion of the bone while stretching the soft tissues over several weeks allowing greater volumetric expansion than conventional techniques. Posterior cranial vault distraction osteogenesis constitutes a more gradual remodeling modality, with infrequent complications. As a first step in intracranial expansion, it preserves the frontal cranium for future frontofacial procedures. A drawback is the need for a second surgery to remove the device, and this must be taken into account during counseling.

Evolution of Cranioorbital Shape in Nonsyndromic, Muenke, and Saethre-Chotzen Bilateral Coronal Synostosis: A Case-Control Study of 2-Year Outcomes

BACKGROUND

The purpose of this study was to quantify change in cranioorbital morphology from presentation, after fronto-orbital advancement, and at 2-year follow-up.

METHODS

Volumetric, linear, and angular analyses were performed on computed tomographic scans of consecutive bilateral coronal synostosis patients. Comparisons were made across three time points, between syndromic and nonsyndromic cases, and against normal controls. Significance was set at p < 0.05.

RESULTS

Twenty-five patients were included: 11 were nonsyndromic, eight had Saethre-Chotzen syndrome, and six had Muenke syndrome. Total cranial volume was comparable to normal, age-matched control subjects before and 2 years after surgery despite an expansion during surgery. Axial and sagittal vector analyses showed advancement and widening of the lower forehead beyond control values with surgery and comparable anterior position, but increased width compared to controls at 2 years. Frontal bossing decreased with a drop in anterior cranial height and advanced lower forehead position. Middle vault height was not normalized and turricephaly persisted at follow-up. Posterior fossa volume remained lower at all three time points compared to control subjects. Supraorbital retrusion relative to anterior corneal position was overcorrected by surgery, with values comparable to those of control subjects at 2 years because of differential growth. There was no difference at 2 years between syndromic and nonsyndromic groups.

CONCLUSIONS

Open fronto-orbital advancement successfully remodels the anterior forehead but requires overcorrection to be comparable to normal at 2 years. Although there are differences in syndromic cases at presentation, they do not result in significant morphometric differences on follow-up. Posterior fossa volume remains lower at all time points.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Foreign Body Reaction to Poly-D-L-Lactic Acid Resorbable Plates Used in Craniofacial Surgery

Resorbable surgical materials are often used in the pediatric population to provide fixation in the growing skeleton. Although foreign body reactions to poly-D-L-lactic acid (PDLLA) plates and screws have been previously reported in other fields, to date PDLLA polymers have been well-tolerated in the setting of craniofacial surgery. The authors report a case of a previously healthy 4-month-old patient with Crouzon syndrome who underwent a frontal-orbital advancement with resorbable PDLLA plates and screws and subsequently experienced extensive foreign body reactions and wound healing complications.