First Vault Expansion in Apert and Crouzon-Pfeiffer Syndromes: Front or Back?

Background: Children with Apert and Crouzon-Pfeiffer syndromes are at risk of intracranial hypertension. Until 2005, when the authors switched to occipital expansion, their institution's preferred treatment was fronto-orbital advancement. However, it was still unclear whether (1) occipitofrontal head circumference (i.e., intracranial volume) was greater after occipital expansion than after fronto-orbital advancement; (2) the incidences of tonsillar herniation and papilledema were lower; and (3) visual acuity was better during follow-up. In these patients, the authors therefore compared fronto-orbital advancement with occipital expansion as the first surgical procedure.

Methods: Measurements included repeated occipitofrontal head circumference as a measure for intracranial volume; neuroimaging to evaluate tonsillar herniation; funduscopy to identify papilledema; and visual acuity testing.

Results: The authors included 37 patients (Apert syndrome, n = 18; Crouzon-Pfeiffer syndrome, n = 19). Eighteen underwent fronto-orbital advancement and 19 underwent occipital expansion (age at surgery, 1.0 versus 1.5 years; p = 0.13). Follow-up time in both groups was 5.7 years. The increase in occipitofrontal head circumference (+1.09 SD) was greater after occipital expansion than after fronto-orbital advancement (+0.32 SD) (p = 0.03). After occipital expansion, fewer patients with Crouzon-Pfeiffer syndrome had tonsillar herniation (occipital, three of 11; fronto-orbital advancement, seven of eight; p = 0.02); for both syndromes together, fewer patients had papilledema (occipital, four of 19; fronto-orbital advancement, 11 of 18; p = 0.02). Visual acuity was similar after fronto-orbital advancement and occipital expansion (0.09 versus 0.13 logarithm of the minimum angle of resolution) (p = 0.28).

Conclusions: The authors' preference for occipital expansion as the initial craniofacial procedure in Apert and Crouzon-Pfeiffer syndromes is supported by the greater increase it produces in intracranial volume (as evidenced by the occipitofrontal head circumference), which reduces the incidences of tonsillar herniation and papilledema.

Clinical Question/level Of Evidence: Therapeutic, III.