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
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- Versatility of the buccinator myomucosal flap in atypical palate reconstructions(2014) FRANCO, Diogo; ROCHA, Diogenes; ARNAUT JR., Marcio; FREITAS, Renato; ALONSO, NivaldoInitially described for the treatment of cleft palate, the anatomical bases of the buccinator myomucosal flap were described by Bozola et al. (1989). A meticulous search found several reports of its use for the correction of post-palatoplasty oronasal fistulas, with only a few reports of its use for other palate-related pathologies. A retrospective analysis was undertaken of patients treated by the Plastic Surgery Units at the Rio de Janeiro Federal University Hospital (HU-UFRJ) and the Sao Paulo University Hospital (HC-USP), suffering from palatal lesions not associated with a cleft palate and treated through the use of buccinator myomucosal flaps. The average age was 47 years, with 70% of the patients being male. Assorted aetiologies were noted for palatal defects. When there was significant damage to the soft palate, a superior base pharyngeal flap was used. Of this total, in 71% of the cases only the buccinator myomucosal flap was used. In all cases, the flaps were unilateral, adequately covering the defects in question. The buccinator myomucosal flap is a good option for reconstructing medium to large palate defects, as it is a flap with good vascularization and dimension, in addition to an ample arc of rotation, with primary closure of the donor site, without adding significant morbidity.
- Normal angulation of skull base in Apert syndrome(2018) LU, Xiaona; FORTE, Antonio Jorge; SAWH-MARTINEZ, Rajendra; WU, Robin; CABREJO, Raysa; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Apert syndrome is characterized by the severe craniofacial deformities. The subsequent process of skeletal maldevelopment is likely to be influenced by multiple interactions at several levels, at a given time. In this study, we aimed to explore the evolution of cranial basal dysmorphology and the chronology of these deformities in Apert syndrome, by objectively analyzing three-dimensional measurements. Fifty-four CT scans from unoperated patients (Apert, n = 18; control, n = 36) were included in this study, with age range from 3 days to 24 years. Before 6 months of age, Apert's anterior cranial base was widened 60%. Between 6 months and 2 years of age, the whole cranial base length, anterior cranial base length and posterior cranial base length decreased 8%, 8% and 14%, respectively. The greater sphenoid wing angle was wider by 26.0 degrees, and continued into adulthood. The cranial base angles did not produce significant changes throughout life. The extra cranial distances synchronously and almost proportionally shortened after later infancy. The anterior and posterior cranial base length shortened at an almost proportional rate. The malformations of the skull vault are additive effects with cranial base fusion on skull length restriction, but the angulation of the skull base is virtually normal.
- Orbitofacial morphology changes with different suture synostoses in Crouzon syndrome(2022) LU, Xiaona; FORTE, Antonio Jorge; JUNN, Alexandra; DINIS, Jacob; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.This study aims to investigate the influence of different cranial vault suture synostoses on orbital and periorbital morphological development in Crouzon syndrome. Computed tomography (CT) scans of Crouzon syndrome patients who had not undergone operation were subgrouped as follows: type I: bicoronal synostosis; type II: sagittal synostosis; type III: pansynostosis; type IV: perpendicular combinations of suture synostoses; and type V: bilateral squamosal synostosis. CT scans were measured using Materialise software. CT scans of 80 Crouzon syndrome patients and 72 normal controls were included. Orbital bony cavity volume was reduced in all subgroups (16-24%), including type V bilateral squamosal synostosis (16%, p = 0.003), although the reduction in type II sagittal synostosis Crouzon patients failed to reach statistical significance (p = 0.071). Globe volume was reduced only in type I bicoronal synostosis (9%, p = 0.018), while the retrobulbar soft tissue volume decreased in type III pansynostosis group by 11% (p = 0.005). Globe volume projection beyond the orbital rim was increased in all groups (p < 0.001), with the greatest increase in type IV perpendicular combination of sutures synostoses, by 100% (p < 0.001). The anteroposterior length of maxilla was significantly shortened in type I (10%, p = 0.028) and type III (9%, p = 0.022) but developed normally in other groups, although the maxilla was posteriorly displaced in all groups (all p <= 0.026). The influence of squamosal synostosis on craniofacial malformation is not equivalent to that of a major vault suture. Therefore, subtype suture fusion individualized surgical interventions, after initial occipital expansion, likely provide additional benefits in mitigating oculo-orbital disproportion.
- Enlarged anterior cranial fossa and restricted posterior cranial fossa, the disproportionate growth of basicranium in Crouzon syndrome(2019) LU, Xiaona; FORTE, Antonio Jorge; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Crouzon syndrome patients develop normal intracranial volume and potential restricted posterior cranial fossa volume with growth. This study aims to trace the segmental anterior, middle and posterior cranial fossae volume, and structural morphology in these patients, in order to help discern more focused and individualized surgical treatment plan. Ninety-two preoperative CT scans (Crouzon, n = 36; control, n = 56) were included, and divided into 5 age related subgroups. CT scans were measured using Mimics and 3-matics software. Overall, Crouzon syndrome patients grew to a 27% (p = 0.011) increased anterior cranial fossa volume and a 20% (p = 0.001) decreased posterior cranial fossa volume, with normal middle cranial fossa and entire intracranial volume measurement. The posterior cranial fossa of Crouzon syndrome initially developed significantly reduced volume (19%, p = 0.032), compared to normals, from 6 months of age, and remained reduced thereafter. The 7.63 mm shortening of posterior cranial fossa length contributed most to the shortened entire cranial length (9.30 mm, p = 0.046). Although the entire cranial volume of Crouzon syndrome is normal overall, the segmental anterior, middle and posterior cranial fossae developed disproportionately. The early significant and lifelong restricted posterior cranial fossa addresses the importance of early posterior cranial expansion. Ideally expansion would have vectors in all three dimensions. (C) 2019 Published by Elsevier Ltd on behalf of European Association for Cranio-Maxillo-Facial Surgery.
- Effectiveness of tranexamic acid for reducing intraoperative bleeding in palatoplasties: A randomized clinical trial(2017) ARANTES, Guilherme C.; PEREIRA, Rui Manoel R.; MELO, Daniela B. de; ALONSO, Nivaldo; DUARTE, Maria do Carmo M. B.Background: Few data are available regarding blood loss during cleft palate surgery. This study assessed the effect of using tranexamic acid in the reduction of intraoperative bleeding. Methods: A double-blind, randomized clinical trial compared intraoperative bleeding and the incidence of oronasal fistulas after palatoplasties in a control group that was given placebo and an intervention group that was given 10 mg/kg tranexamic acid followed by a continuous infusion of 1 mg/kg/h of the same until the end of surgery. Patients who underwent primary palatoplasty with no known or suspected coagulation disorders at our institution during the study period were included in the study. Results: 70 patients were allocated, 66 received the intervention. Blood loss was reduced by 11.9%, without statistical significance. The incidence of fistulas in the intervention and control groups was 12.9% and 18.75%, respectively. The reduction of 5.8% (Cl 95%: 12%-23.8%) was not significant. Conclusions: The reduction of intraoperative blood loss was lower than expected and not statistically significant; a larger sample is needed to confirm the observed reduction. The drug did not seem to have negative effects on flap viability. (C) 2016 Published by Elsevier Ltd on behalf of European Association for Cranio-Maxillo-Facial Surgery.