NIVALDO ALONSO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cirurgia, Faculdade de Medicina - Docente
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/04 - Laboratório de Microcirurgia, Hospital das Clínicas, Faculdade de Medicina - Líder
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/04 - Laboratório de Microcirurgia, Hospital das Clínicas, Faculdade de Medicina - Líder
3 resultados
Resultados de Busca
Agora exibindo 1 - 3 de 3
- Racial disparity in orbital morphology and spatial relations in unoperated Crouzon patients(2021) LU, X.; FORTE, A. J.; FAN, F.; ZHANG, Z.; TENG, L.; YANG, B.; ALPEROVICH, M.; STEINBACHER, D. M.; ALONSO, N.; PERSING, J. A.The altered orbital morphology of patients with Crouzon syndrome could have an impact on the planning of treatment in diverse populations, in spite of the confounding influences of different cranial suture synostosis. This study attempted to explore the differences in orbital characteristics between Asian, Caucasian patients with Crouzon syndrome, associated pansynostosis. Eighty-six preoperative computed tomograms (CT) were included (Asian Crouzon syndrome: n=10; Asian controls: n=24; Caucasian Crouzon syndrome: n=19; Caucasian controls: n=33) and measured using Mimics software (Materialise). Unique cephalometric measurements related to orbital morphology and position were designed. Crouzon syndrome and race both have interactive effects on protrusion of the globe (p=0.009) and medial horizontal angle (p=0.012) in the assessment of orbital morphology. They also interact in the width of the ethmoid sinus (p=0.009) and influence bilateral orbital relations. The anteroposterior orbital roof in Caucasian patients with Crouzon syndrome was shortened by 4.09 mm (p=0.002) compared with Caucasian controls. However, in Asian patients this dimension developed normally. The anteroposterior orbital floor was significantly reduced to a similar extent in both Asian and Caucasian Crouzon patients (both p<0.001). The visual axes in Caucasian patients with Crouzon showed more inferior rotation, by 4.38 degrees (p=0.031) than they did in Caucasian controls, but did not achieve a statistically significant difference in other comparisons. The effect of Crouzon syndrome on orbital malformation and placement is influenced by race, especially structures related to the ethmoid sinus. Asian patients need greater infraorbital advancement for better correction of orbital proptosis and aesthetic benefits, but may require less fronto-orbital advancement than Caucasian patients.
- Nasopharyngeal airway and subcranial space analysis in Pfeiffer syndrome(2021) LU, X.; FORTE, A. J.; ALLAM, O.; PARK, K. E.; JUNN, A.; ALPEROVICH, M.; STEINBACHER, D. M.; TONELLO, C.; ALONSO, N.; PERSING, J. A.Tracheotomy in infancy helps patients with Pfeiffer syndrome to survive by preventing respiratory crisis, but difficulty in decannulation may consequently be a challenge. This study has investigated the regional abnormalities of the nasopharyngeal airway in children with Pfeiffer syndrome to provide an anatomical basis for the surgical treatment and decannulation of the upper airway. Seventy-two preoperative computed tomograms (CT) (Pfeiffer syndrome n=30; control n=42) were included. The airway volume, cross-sectional area, and cephalometrics were measured using Materialise software. Patients with Pfeiffer syndrome developed a 50% (p<0.001) reduction of nasal airway volume, and a 44% (p=0.003) restriction in pharyngeal airway volume. In patients with Pfeiffer syndrome the cross-sectional area at the choana was only half that of the controls (p<0.001). The posterior width of the nasal airway in patients with Pfeiffer syndrome was shortened by 13% (p=0.003), and the height reduced by 21% (p<0.001). The cross-sectional areas at the condylion and gonion levels, which indicate the calibre of the pharyngeal airway at the entrance and midsection, were reduced by 67% (p<0.001) and 47% (p<0.001), respectively, when compared with the controls. The volume of the nasal airway in patients with Pfeiffer syndrome was significantly restricted in length, height, and width, and by choanal stenosis in all cases in this cohort. The reduced anteroposterior length of the nasal airway contributed to the shortened maxilla more than the anteroposterior position. The limited height and width of the nasal pathway was the result of a hypoplastic sphenoid. Restricted mediolateral and anteroposterior dimensions were evident across the entire course of the pharyngeal airway. Mediolateral maxillary expansion in addition to maxillomandibular advancement is therefore likely to benefit these patients.
- Growth patterns of the airway in Crouzon syndrome patients with different types of cranial vault suture synostosis(2021) LU, X.; FORTE, A. J.; WILSON, A.; PARK, K. E.; ALLAM, O.; ALPEROVICH, M.; STEINBACHER, D. M.; TONELLO, C.; ALONSO, N.; PERSING, J. A.The severity of obstructive respiratory difficulty varies among affected Crouzon syndrome patients. The aim of this study was to investigate the correlation between the restricted airway volume in Crouzon syndrome and the associated type of cranial vault suture synostosis. Computed tomography scans of 68 unoperated Crouzon syndrome patients and 89 control subjects were subgrouped into four types: type I, bilateral coronal synostosis; type II, sagittal synostosis; type III, pansynostosis; type IV, perpendicular combinations of synostoses. Measurements were made using Mimics software. Of type I Crouzon patients, 42% had a restricted nasal airway (P = 0.002), while the pharyngeal airway volume was not significantly reduced. Type II Crouzon patients grew normal segmental airway volumes. Crouzon patients of type III developed simultaneously reduced nasal and pharyngeal airway volumes in infancy, by 38% (P = 0.034) and 51% (P = 0.014), respectively. However, the nasal airway achieved a normal volume by 2 years of age without any intervention, while the pharyngeal airway remained significantly reduced up to 6 years of age, by 42% (P = 0.013), compared to controls. Type IV Crouzon patients developed a reduced nasal airway volume (32%, P = 0.048) and a non-significant restricted pharyngeal airway (18%, P = 0.325). Airway compromise in Crouzon syndrome is variable when associated with different craniosynostosis fusion patterns. Type II (sagittal synostosis) Crouzon patients grew a normal nasopharyngeal airway volume. Those with types I (bicoronal synostosis) and IV (perpendicular synostoses) had significantly restricted nasal airways and a tendency towards a reduced pharyngeal volume. Type III (pansynostosis) Crouzon infants had the worst restriction of both airways, although there was some improvement with age.