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
4 resultados
Resultados de Busca
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- Midface Morphology and Growth in Syndromic Craniosynostosis Patients Following Frontofacial Monobloc Distraction(2021) TONELLO, Cristiano; CEVIDANES, Lucia H. S.; RUELLAS, Antonio C. O.; ALONSO, NivaldoBackground: Facial advancement represents the essence of the surgical treatment of syndromic craniosynostosis. Frontofacial monobloc distraction is an effective surgical approach to correct midface retrusion although someone consider it very hazardous procedure. The authors evaluated a group of patients who underwent frontofacial monobloc distraction with the aim to identify the advancement results performed in immature skeletal regarding the midface morphologic characteristics and its effects on growth. Methods: Sixteen patients who underwent frontofacial monobloc distraction with pre- and postsurgical computed tomography (CT) scans were evaluated and compared to a control group of 9 nonsyndromic children with CT scans at 1-year intervals during craniofacial growth. Three-dimensional measurements and superimposition of the CT scans were used to evaluate midface morphologic features and longitudinal changes during the craniofacial growth and following the advancement. Presurgical growth was evaluated in 4 patients and postsurgical growth was evaluated in 9 patients. Results: Syndromic maxillary width and length were reduced and the most obtuse facial angles showed a lack in forward projection of the central portion in these patients. Three-dimensional distances and images superimposition demonstrated the age did not influence the course of abnormal midface growth. Conclusion: The syndromic midface is hypoplastic and the sagittal deficiency is associated to axial facial concavity. The advancement performed in mixed dentition stages allowed the normalization of facial position comparable to nonsyndromic group. However, the procedure was not able to change the abnormal midface architecture and craniofacial growth.
- Facial Dysmorphology in Saethre-Chotzen Syndrome(2021) JUNN, Alexandra; DINIS, Jacob; LU, Xiaona; FORTE, Antonio Jorge; MOZAFFARI, Mohammad Ali; PHILLIPS, Sarah; LOPEZ, Joseph; ALONSO, Nivaldo; PERSING, John A.; ALPEROVICH, MichaelPurpose: Classic features of Saethre-Chotzen syndrome (SCS) described in the literature include a prominent nasal bridge, eyelid ptosis, telorbitism, maxillary hypoplasia, and mandibular prognathism. The purpose of this study was to evaluate objectively the bony features of SCS. Methods: Preoperative computer tomography scans of 15 SCS patients, 23 normal controls, 13 bicoronal nonsyndromic, and 7 unicoronal nonsyndromic craniosynostosis patients were included for analysis. Unaffected controls and nonsyndromic patients were age- and sex-matched to SCS patients. Morphometric cephalometrics were analyzed using three-dimensional computer tomography reconstructions. Mann-Whitney U were used to compare facial measurements between SCS and normal and nonsyndromic craniosynostosis controls. Results: Telorbitism was present in bicoronal SCS patients only (P = 0.04) but absent in the unicoronal and bicoronal/metopic cohorts. The angle of the nasal bone relative to the sella was not different between SCS and controls (P = 0.536), although the angle of the nasal bone relative to the forehead was decreased in SCS by 15.5 degrees (P < 0.001). Saethre-Chotzen syndrome had a 2.6 degrees maxillary retrusion relative to controls (P = 0.03). In addition, SCS patients aged 4 to 7 months had a wider (39.34 versus 35.04, P = 0.017) and anteroposteriorly foreshortened (32.12 versus 35.06, P = 0.039) maxilla. There was no difference in mandibular prognathism among SCS patients as measured by the sella-nasion-B point angle compared to controls (P = 0.705). Conclusions: Despite classic descriptions, on morphometric analysis SCS patients did not demonstrate consistency across all suture subtypes in terms of telorbitism, a broad nasal bridge, or mandibular prognathism. Rather, SCS subtypes of SCS based on suture pathology more closely resemble nonsyndromic patients.
- 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.
- Sphenoid Bone Structure and Its Influence on the Cranium in Syndromic Versus Nonsyndromic Craniosynostosis(2021) LU, Xiaona; FORTE, Antonio Jorge; PARK, Kitae Eric; ALLAM, Omar; MOZAFFARI, Mohammad Ali; ALPEROVICH, Michael; STEINBACHER, Derek M.; ALONSO, Nivaldo; PERSING, John A.Background: Little is known about the detailed growth of the sphenoidal and temporal bones, even though they contribute significantly to the cranial base and cranial fossa skeletons. They also serve to connect the cranial vault with facial structure. This study details their morphologic development in isolated bicoronal synostosis and associated syndromes. Methods: Eighty-one CT scans were included (nonsyndromic bicoronal synostosis, n = 28; Apert syndrome associated with bicoronal synostosis, n = 19; Crouzon syndrome associated with bicoronal synostosis, n = 8; and controls, n = 26), and measured using Materialize software. Results: Sphenoidal and temporal bone volumes in nonsyndromic bicoronal synostosis are reduced 23% (P = 0.005) and 24%(P = 0.003) at 6 months of age, compared to controls. Apert and Crouzon syndrome patients developed similar reduced volumes. The greater wing of the sphenoid and pterygoid processes in nonsyndromic bicoronal synostosis are initially inferiorly rotated at 2 months of age, by 9.608 (P = 0.002) and 4.338 (P = 0.023), respectively. In Apert syndrome, these rotations were reduced by 4.828 (P = 0.003) and 12.608 (P < 0.001), (like Crouzon syndrome). However, in Apert syndrome, the length of pterygoid processes is shortened by 11% (P = 0.018) compared to nonsyndromic bicoronal synostosis. Crouzon syndrome skulls did not develop a statistically significant shortening relative to nonsyndromic bicoronal synostosis. Mediolateral expansion of the sphenoid in nonsyndromic bicoronal synostosis was less than normal (P = 0.023), and it was further reduced in syndromic skulls. Conclusion: Isolated bicoronal synostosis tends to reduce the volume of sphenoidal and temporal bones, and inferior and posterior rotation of the entire sphenoid. Syndromic conditions restrict sphenoidal rotation, and limit the expansion of sphenoidal greater wing and pterygoid plate.