BACKGROUND: Surgical correction of unicoronal craniosynostosis (UCS) is highly complex due to its asymmetric appearance. Although fronto-orbital advancement (FOA) is a versatile technique for craniosynostosis correction, harmonization of the orbital bandeau in UCS is difficult to predict. This study evaluates the biomechanics of the orbital bandeau using different patterns and varying characteristics of inner cortical bone layer osteotomies in a finite element (FE) analysis.
METHODS: An FE model was created using the computed tomography (CT) scan of a 6.5-month-old male infant with a right-sided UCS. The unaffected side of the orbital bandeau was virtually mirrored, and anatomical correction of the orbital bandeau was simulated. Different combinations of osteotomy patterns, numbers, depths, and widths were examined (n = 48) and compared to an uncut model.
RESULTS: Reaction forces and maximum stress values differed significantly (p < 0.01) among osteotomy patterns and between each osteotomy characteristic. Regardless of the osteotomy pattern, higher numbers of osteotomies significantly (p < 0.05) correlated with reductions in reaction force and maximum stress. An X-shaped configuration with three osteotomies deep and wide to the bone was biomechanically the most favorable model.
CONCLUSIONS: Inner cortical bone layer osteotomy might be an effective modification to the conventional FOA approach in terms of predictable shaping of the orbital bandeau.

BACKGROUND: Craniofacial asymmetry associated with unicoronal synostosis (UCS) may persist into the teenage years despite surgery in infancy. This study evaluated outcomes following a nasal monobloc procedure by mobilizing a united nasomaxillary and bilateral medial orbital segment of bone (nasal monobloc) to perform corrective translational and rotational movement for secondary correction of residual nasal-orbital asymmetry associated with UCS.
METHODS: A retrospective review of all UCS patients treated with nasal monobloc at our institution was performed. Demographic information was recorded, and pre- and postoperative 2D imaging was used for morphometric outcome analysis. Outcomes and complications were tabulated.
RESULTS: The study included 14 patients (5 males, 9 females; mean age 14.6 years; range 9.6 to 22.5 years; mean follow-up 70.6 months range 12 to 132 months). Ancillary procedures (scar revision, forehead/orbital contouring, MEDPOR® augmentation) were performed in all patients at the time of the nasal monobloc. One patient underwent a repeat procedure 6 years later following technique modification. Additionally, another patient experienced late overgrowth of the frontal sinus with forehead asymmetry. The morphometric analysis demonstrated significant (p < 0.05) pre-op to post-op improvements in naso-orbital asymmetry, as demonstrated by horizontal orbital aperture ratio (0.88 vs 0.99), midline to exocanthion ratio (0.91 vs 0.98), orbital index ratio (1.15 vs 1.01), and midline discrepancy (7.1 degrees vs 2.7 degrees).
CONCLUSIONS: Nasal monobloc osteotomy provides a reasonable surgical treatment to improve both the nasal and orbital asymmetries associated with unicoronal synostosis, including frontal nasal deviation, basal nasal deviation, and orbital aperture asymmetry. It is important to note that confounding anatomic variables such as globe dystopia, strabismus, and scleral show may affect the perception of orbital symmetry.

(1) Background: Non-syndromic unicoronal craniosynostosis (UCS) is associated with a high prevalence of ocular anomalies. Currently, the etiology of this association remains obscure, however, it is presumed to be primarily attributed to their orbital malformations and/or secondary to craniofacial surgery. We assessed pre-operative ophthalmological examinations of non-syndromic UCS patients and compared them with their postoperative outcomes and long-term follow-up. (2) Methods: A retrospective case series was conducted on medical records of patients with non-syndromic UCS at Sophia Children\'s Hospital, Rotterdam. Ophthalmologic examinations were collected at different time periods: T1 (first visit), T2 (<1 year after cranioplasty), and T3 (long-term follow-up at last visit). The McNemar\'s test was used for statistical analysis. (3) Results: A total of 101 patients were included, for whom examinations were available at T1 and T3. Patients had a mean age of 2.8 years (±2.7) and 9.5 (±4.9) at T1 and T3, respectively. At T1, 52 patients (51.5%) were diagnosed with strabismus, and 61 patients (60.4%) at T3. Vertical strabismus increased significantly from 23 patients (22.8%) at T1 to 36 patients (35.6%) at T3 (p = 0.011). Followed by astigmatism, which increased significantly from 38 (37.6%) at T1 to 59 (58.4%) patients at T3 (p = 0.001). T1 was available in 20 patients prior to fronto-orbital advancement (FOA), therefore, a sub-analysis was conducted on these patients, which was followed shortly after FOA at T2. Prior to FOA, strabismus was present in 11 patients (55.0%) and in 12 patients (60.0%) at T2. After FOA, strabismus worsened in two patients. (4) Conclusions: This study showed the high prevalence of ocular anomalies in patients with non-syndromic UCS before and after cranioplasty and at long-term follow-up. The findings of this study show that ophthalmic and orthoptic examinations are an important part of the optimal treatment of patients with non-syndromic UCS.

OBJECTIVE: Unicoronal craniosynostosis (UCS) is characterized by complex orbital deformity and is typically treated by asymmetrical fronto-orbital remodeling (FOR) during the 1st year of life. The aim of this study was to elucidate to what extent orbital morphology is corrected by surgical treatment.
METHODS: The extent to which orbital morphology was corrected by surgical treatment was tested by analysis of differences in volume and shape between synostotic, nonsynostotic, and control orbits at two time points. In total, 147 orbits were analyzed from patient CT images obtained preoperatively (mean age 9.3 months), at follow-up (mean age 3.0 years), and in matched controls. Semiautomatic segmentation software was used to determine orbital volume. For analysis of orbital shape and asymmetry, geometrical models, signed distance maps, principal modes of variation, and three objective parameters (mean absolute distance, Hausdorff distance, and dice similarity coefficient) were generated by statistical shape modeling.
RESULTS: Orbital volumes on both the synostotic and nonsynostotic sides were significantly smaller at follow-up than volumes in controls and significantly smaller both preoperatively and at follow-up than orbital volumes on the nonsynostotic side. Significant differences in shape were identified globally and locally, both preoperatively and at 3 years of age. Compared with controls, deviations were mostly found on the synostotic side at both time points. Asymmetry between synostotic and nonsynostotic sides was significantly decreased at follow-up, but not compared with the inherent asymmetry of controls. On a group level, the preoperative synostotic orbit was mainly expanded in the anterosuperior and anteroinferior regions and smallest on the temporal side. At follow-up, the mean synostotic orbit was still larger superiorly but also expanded in the anteroinferior temporal region. Overall, the morphology of nonsynostotic orbits was more similar to that of controls than to synostotic orbits. However, the individual variation in orbital shape was greatest for nonsynostotic orbits at follow-up.
CONCLUSIONS: In this study, the authors presented what is, to their knowledge, the first objective automatic 3D bony evaluation of orbital shape in UCS, defining in greater detail than has been done previously how synostotic orbits differ from nonsynostotic and control orbits, and how orbital shape changes from 9.3 months of age preoperatively to 3 years of age at the postoperative follow-up. Despite surgical treatment, both local and global deviations in shape persist. These findings may have implications for future directions in the development of surgical treatment. Future studies connecting orbital morphology to ophthalmic disorders, aesthetics, and genetics could provide further insight to enable better outcomes in UCS.

Fronto-orbital advancement and remodeling (FOAR) is among the most common surgical approaches for unicoronal craniosynostosis (UCS), although some data demonstrate failure to achieve long-term aesthetic normalcy, leading some to seek alternative treatment paradigms such as fronto-orbital distraction osteogenesis (FODO). This study compares long-term aesthetic outcomes of patients with UCS treated with FOAR and FODO.
Twenty patients (four males) with non-syndromic UCS presenting to our institution and undergoing distraction were compared to a matched cohort of 20 patients (six males) undergoing FOAR. Clinical photographs and ImageJ were used to quantify periorbital anatomy including palpebral fissures, pupil-to-brow distance (PTB), and margin-reflex distance (MRD1) in pixels. Whitaker classification was blindly assigned by craniofacial surgeons.
Photogrammetric analysis and Mann-Whitney U tests demonstrated significantly improved postoperative symmetry in distraction patients for palpebral width (p = 0.020), MRD1 (p = 0.045), and canthal tilt (p = 0.010). Average Whitaker classification scores between FOAR (1.94) and distraction (1.79) cohorts were similar (p = 0.374).
UCS patients demonstrated significant postoperative improvements in periorbital symmetry, with distraction patients demonstrating superior results in palpebral width and canthal tilt. FOAR and FODO patients achieved similar Whitaker classification scores. These cohorts will be followed until craniofacial maturity prior to making any definitive conclusions.

Unicoronal craniosynostosis correction with fronto-orbital advancement and cranial vault remodeling has traditionally been the gold standard. Distraction osteogenesis has the advantage of increased size of movement without constriction of the scalp and decreased morbidity. Although fronto-orbital advancement and cranial vault remodeling are usually performed at 6 months of age or later, distraction osteogenesis is performed at a younger age, between 3 and 6 months, to take advantage of the infant bony physiology. Herein, the authors demonstrate a case of distraction osteogenesis for unicoronal craniosynostosis in a 3-month-old female with significant improvement of her orbital, nasal, and frontal symmetry. The video can be found here: https://vimeo.com/519047922.

Unicoronal craniosynostosis is notoriously difficult to treat, with long-term studies demonstrating high rates of relapse and the need for reoperation using open fronto-orbital advancement. Applying the principles of distraction osteogenesis to cranial vault remodeling has demonstrated promising short-term results that compare favorably with traditional methods, with simultaneous correction of both frontofacial and endocranial morphology, along with significant increases in intracranial volume. Here, the authors demonstrate their technique for rotation flap distraction osteogenesis in the treatment of unicoronal synostosis and provide case examples. The video can be found here: https://vimeo.com/519505008.

The current literature on unilateral coronal craniosynostosis is replete with repair techniques and surgical outcomes; however, information regarding neurodevelopment remains unclear. Therefore, the aim of this systematic review and meta-analysis was to comprehensively assess the neurodevelopmental outcomes of patients with unicoronal craniosynostosis compared with their healthy peers or normative data.
A systematic review of the Ovid MEDLINE, Embase, Web of Science, Scopus, Cochrane Library, and ClinicalTrials.gov databases from database inception to January 19, 2022, was performed. Included studies assessed neurodevelopment of patients with unicoronal craniosynostosis. Two independent reviewers selected studies and extracted data based on a priori inclusion and exclusion criteria. Results of developmental tests were compared with normative data or controls to generate Hedges\' g statistics for meta-analysis. The quality of included studies was evaluated using the National Institutes of Health Assessment Tool.
A total of 19 studies were included and analyzed, with an overall fair reporting quality. A meta-analysis of 325 postoperative patients demonstrated that scores of general neurodevelopment were below average but within one standard deviation of the norm (Hedges\' g = -0.68 [95% CI -0.90 to -0.45], p < 0.001). Similarly, postoperative patients exhibited lower scores in verbal, psychomotor, and mathematic outcome assessments.
This systematic review and meta-analysis found that patients with unicoronal craniosynostosis had poorer neurodevelopment, although scores generally remained within the normal range. These data may guide implementation of regular neurocognitive assessments and early learning support of patients with unicoronal craniosynostosis.

Despite a greater awareness of the differential diagnosis of head shape abnormalities among pediatricians, the effect of deformational forces on calvarial morphology can complicate the diagnosis of craniosynostosis. In this report, we describe 2 patients diagnosed with unicoronal craniosynostosis (UCS) in a delayed fashion due to the presence of concomitant posterior deformational plagiocephaly (PDP). In both cases, the severity of each patients\' PDP obscured changes typically associated with UCS. This unique presentation underscores the importance of having a high index of suspicion for possible premature suture fusion despite the presence of concomitant PDP.

BACKGROUND: Endoscopic strip craniectomy with helmeting (ESCH) has been shown to be a safe and efficacious alternative to fronto-orbital remodeling (FOR) for selected children with craniosynostosis. In addition to clinical factors, there may be economic benefits from the use of ESCH instead of FOR.
METHODS: A retrospective review of 23 patients with nonsyndromic unicoronal craniosynostosis (UCS) treated with FOR was carried out at Great Ormond Street Hospital (GOSH) for Children in London, UK. Secondary data were used for the ESCH cohort from a paper published by Jimenez and Barone (2013). Data were collected on surgical time, transfusion rates, length of hospital stay, adverse event rates, reintervention rates, and overall costs. Costs were categorized and then assigned to the appropriate data sets.
RESULTS: The mean age of patients undergoing FOR (vs. ESCH) was 17.4 mo (vs. 3.1 mo) with a mean surgical time of 234 min (vs. 55 min), mean transfusion volume of 221.6 mL (vs. 80.0 mL), mean transfusion rate of 14/23 (vs. 2/115), and a total immediate overnight stay of 3.13 days (vs. 97% next-day discharge). The FOR group had a higher adverse event rate (5/23 vs. 4/115, p=<0.005) and a higher number requiring extraocular muscle surgery (4/23 vs. 7/109, p=0.16). There was a substantial difference in overall costs between the two groups. Total variance cost for the FOR group was £7436.5 vs. £4951.35, representing a cost difference of £2485.15 over the 24-month study period.
CONCLUSIONS: ESCH, in comparison to FOR, appears as a more economical method in the management of USC patients, as well as having clinical benefits including reduced adverse event rate and improved ophthalmic outcomes.