Nasopharyngeal airway and subcranial space analysis in Pfeiffer syndrome

Orbital and Periorbital Dysmorphology in Untreated Pfeiffer Syndrome

BACKGROUND

Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear.

METHODS

Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software.

RESULTS

Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001).

CONCLUSIONS

Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Tracheal cartilaginous sleeve in Pfeiffer syndrome: lesson learnt from its rarity

Pfeiffer syndrome is a rare inherited craniofacial disorder. Upper airway obstruction is common among patients with Pfeiffer syndrome due to craniosynostosis. They may also present with lower respiratory tract obstruction due to a rare congenital airway malformation called tracheal cartilaginous sleeve (TCS). We report the case of a patient with Pfeiffer syndrome who presented with recurrent bronchopneumonia, discovered incidentally to have TCS via direct visualisation during tracheostomy. Relevant literature for this rare clinical condition are reviewed and discussed. Clinicians should be aware of TCS when encountering patients with craniosynostosis who present with recurrent lower respiratory tract infections. Careful and meticulous investigations should be performed to look for TCS, especially in patients with craniosynostosis.

Airway Growth in Preoperative Patients with Crouzon Syndrome

Background: Obstructive sleep apnea is common in patients with Crouzon syndrome, yet it may be caused by multiple factors. This study aims to investigate the natural history of airway development in preoperative Crouzon patients, from infants to adults. Methods: Preoperative computed tomography (CT) scans (Crouzon syndrome, n = 73; control, n = 87) were divided into five age subgroups. CT scans were measured using Materialise software. Results: Before 6 months of age, nasal airway volume in patients with Crouzon syndrome was smaller than normal by 37% (p = 0.002), and the cross-sectional area at the choana reduced by 45% (p < 0.001). The reduction of nasal airway volume and cross-sectional area reached their nadir at 2 years of age, with shortening of 44% and 63% (both p < 0.001), respectively. They gradually caught up to normal dimensions after 6 years of age. Between 2 and 6 years, the pharyngeal airway in patients with Crouzon syndrome reduced 44% (p = 0.011) compared with controls. However, the airway cross-sectional area at condylion and gonion levels was less than normal, before 6 months (35%, p = 0.024) and (44%, p = 0.006) after 2 years of age, respectively. This reduction remains into adulthood. Conclusion: Nasal airway volume is more limited in children with Crouzon syndrome who are younger than 2 years of age. Whereas after 2 years of age, the pharyngeal airway develops significant volume restriction, leading to timing and specific treatment area foci based on the site of temporal maximal constriction.