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
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- 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.
- Morphological Basis for Airway Surgical Intervention in Apert Syndrome(2021) LU, Xiaona; FORTE, Antonio Jorge; PARK, Kitae Eric; ALLAM, Omar; ALPEROVICH, Michael; STEINBACHER, Derek M.; TONELLO, Cristiano; ALONSO, Nivaldo; PERSING, John A.Objective Previous studies have explored the restricted nasopharyngeal airway in Apert syndrome patients. This study aims to investigate the segmented airway volume changes with age and directly analyze their correlations with subcranial dimensions and angulations. Methods Ninety-seven preoperative computed tomography scans (Apert, n = 44; control, n = 53) were included in this study, and divided into 5 age-related subgroups. Computed tomography scans were measured using Mimics and 3-matics software. Results Before 6 months of age, the nasal cavity in Apert syndrome is reduced by 47% (P = 0.002), which gradually approximates normal thereafter; however, there remained a 30% reduction, compared with controls. It is highly correlated with the anteroposterior length of subcranial space, and the position of maxilla and palate. The pharyngeal airway volume in Apert syndrome patients, younger than 6 months, was larger than normal by 129% (P = 0.013). However, between 2 and 6 years of age, the pharyngeal airway becomes smaller than normal, with a 57% (P = 0.010) reduction in childhood and 52% (P = 0.005) in adolescence. It is closely correlated with the intercondylar and intergonial widths. Conclusions Airway compromise in Apert syndrome patients is attributable more to the nasal cavity in infants, but in the older child, it is the pharyngeal region. The restricted nasal airway in Apert syndrome is correlated with the subcranial space length and width, but independent of cranial base flexion. The pharyngeal airway volume in Apert syndrome is not as highly correlated with craniofacial morphology. Rather, it is impacted by the growth of mandible, which often requires surgical intervention later in childhood.
- 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.
- Cephalocranial Disproportionate Fossa Volume and Normal Skull Base Angle in Pfeiffer Syndrome(2021) LU, Xiaona; FORTE, Antonio Jorge; ALLAM, Omar; PARK, Kitae Eric; ALPEROVICH, Michael; STEINBACHER, Derek M.; TONELLO, Cristiano; ALONSO, Nivaldo; PERSING, John A.Background: Pfeiffer syndrome is a rare syndromic craniosynostosis disorder, with a wide range of clinical manifestations. This study aims to investigate the structural abnormalities of cranial fossa and skull base development in Pfeiffer patients, to provide an anatomic basis for surgical interventions. Method: Thirty preoperative CT scans of Pfeiffer syndrome patients were compared to 35 normal controls. Subgroup comparisons, related to differing suture synostosis, were performed. Results: Overall, the volume of anterior and middle cranial fossae in Pfeiffer patients were increased by 31% (P < 0.001) and 19% (P = 0.004), versus controls. Volume of the posterior fossa in Pfeiffer patients was reduced by 14% (P = 0.026). When only associated with bicoronal synostosis, Pfeiffer syndrome patients developed enlarged anterior (68%, P = 0.001) and middle (40%, P = 0.031) fossae. However, sagittal synostosis cases only developed an enlarged anterior fossa (47%, P < 0.001). The patients with solely bilateral squamosal synostosis, developed simultaneous reduced anterior, middle and posterior cranial fossae volume (all P <= 0.002). The overall skull base angulation, measured on both intracranial and subcranial surfaces, grew normally. Conclusion: Enlarged anterior cranial fossae in Pfeiffer syndrome children is evident, except for the squamosal synostosis cases which developed reduced volume in all fossae. Volume of the middle cranial fossa is influenced by associated cranial vault suture synostosis, specifically, sagittal synostosis cases develop normal middle fossa volume, while the bicoronal cases develop increased middle fossa volume. Posterior cranial fossa development is restricted by shortened posterior cranial base length. Surgical intervention in Pfeiffer syndrome patients optimally should be indexed to different suture synostosis.
- Sinus pericranii-unusual anatomic obstacle to posterior decompression on an amniotic band sequence(2021) TONELLO, Cristiano; BRANDAO, Michele Madeira; ALONSO, NivaldoAbnormal venous drainage in patients with craniofacial anomalies is relativity uncommon. Sinus pericranii is a rare vascular malformation characterized by communication between intracranial dural sinuses and extracranial venous drainage systems. The association between sinus pericranii and amniotic band syndrome has not been described. We report on a 7-month-old girl diagnosed with amniotic band sequence who underwent posterior fossa decompression due to intracranial hypertension and Chiari malformation type I. The computed tomography and magnetic resonance identified the connection between the sagittal sinus and the scalp. During the operation, the presence of sinus pericranii was a complicating factor limiting the proper exposure because of the risk of bleeding. Patients with craniofacial anomalies and sinus pericranii present an increased risk of serious surgical complications and consequences from craniofacial surgery, especially from cranioplasty and posterior decompression. Special attention must be paid to abnormal venous drainage, and vascular imaging studies are sometimes required.