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
13 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 13
- Temporal Evaluation of Craniofacial Relationships in Apert Syndrome(2019) LU, Xiaona; FORTE, Antonio Jorge; SAWH-MARTINEZ, Rajendra; WU, Robin; CABREJO, Raysa; GABRICK, Kyle; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Complicated craniofacial malformations interfacing with multiple intracellular regulatory mechanisms, lead to ambiguous growth patterns in Apert syndrome. This study aims to explore the chronology and pathogenesis of the development of craniofacial anatomic relationships and to verify the positional correlates between skull and facial structures in Apert syndrome. Fifty-four computed tomography scans (Apert, n = 18; control, n = 36) were included and divided into 3 age subgroups. Craniofacial 3-dimensional cephalometries were analyzed by Materialize software. The angle between sella-nasion plane and maxillary plane widens 7.748 (P = 0.003) prior to 6 months of age; thereafter, this widening increases by 10.368 (P< 0.001) in 6 months to 2 years of age, and remains increased by 8.98 (P = 0.046) throughout childhood. The angle between Frankfort horizontal plane and maxillary plane widens 5.178 (P = 0.022) before 6 months. Angles SNA, SNB, and ANB showed decreases, averaging 12.238 (P< 0.001), 5.198 (P = 0.004), and 6.728 (P = 0.001), respectively. The linear measurements showed synchronicity and continuing deformity into adulthood. Between 6 months to 2 years of age, the distance from sella to nasion (S-N), anterior nasal spine (S-ANS), and posterior nasal spine (S-PNS) decreased 8% (P = 0.006), 16% (P< 0.001), and 19% (P = 0.002), respectively, and remained shortened into adulthood. The angulation changes occur earlier in development than linear distance reduction in Apert syndrome patients compared with controls. Angular adjustments were not sufficient to maintain normal cranial base length. Facial deformity of Apert syndrome temporally begins with the midface, and affects orbit and mandible later in life.
- Profiling recent medical graduates planning to pursue surgery, anesthesia and obstetrics in Brazil(2019) GUILLOUX, Aline Gil Alves; RAMOS, Jania A.; CITRON, Isabelle; ROA, Lina; AMUNDSON, Julia; MASSENBURG, Benjamin B.; SALUJA, Saurabh; MIOTTO, Bruno Alonso; ALONSO, Nivaldo; SCHEFFER, Mario CesarBackground: Lack of providers in surgery, anesthesia, and obstetrics (SAO) is a primary driver of limited surgical capacity worldwide. We aimed to identify predictors of entry into Surgery, Anesthesia, and Obstetrics and Gynecology (SAO) fields and preference of working in the public sector in Brazil which may help in profiling medical students for recruitment into these needed areas. Methods: A questionnaire was applied to all Brazilian medical graduates registered with a Board of Medicine from 2014 to 2015. Twenty-three characteristics were analyzed. Logistic regression was used to determine predictors' influence on outcome. Results: There were 4601 (28.2%) responders to the survey, of which 40.5% (CI 34.7-46.5%) plan to enter SAO careers. Of the 23 characteristics analyzed, eight differed significantly between those who planned to work in SAO and those who did not. Of those eight characteristics, just three were significant predictors in the regression model: preference for working in the hospital setting, having spent more than 70% of their clinical years in practical activities, and valuing the substantial earning potential. These three factors explained only 6.3% of the variance in SAO preference. Within the graduates who preferred SAO careers, there were only two predictors for working in the public sector (""preparatory time before medical school"" and valuing ""prestige/status""). Conclusions: Factors affecting specialty and sector choice are multifaceted and difficult to predict. Future programs to fill provider gaps should identify methods other than medical student profiling to assure specialty and sector needs are met.
- Orbit, zygoma, and maxilla growth patterns in Crouzon syndrome(2019) LU, X.; FORTE, A. J.; SAWH-MARTINEZ, R.; WU, R.; CABREJO, R.; STEINBACHER, D. M.; ALPEROVICH, M.; ALONSO, N.; PERSING, J. A.The facial malformations of Crouzon syndrome involve the entire cranioorbito-zygomatic region. The detailed sequence of changes in orbit, zygoma, and maxilla over time, the mutual influence among these three anatomical structures, and their relationship with the cranial base were studied to determine the sequence and timing of deformity. Preoperative CT scans of 36 patients with Crouzon syndrome (mean age 10.84 +/- 14.70 years; 14 male, 22 female) and CT scans of 54 control subjects (mean age 8.53 +/- 13.22 years; 29 male, 25 female) were divided into five subgroups by age: 0-6 months, 6 months-2 years, 2-6 years, 6-18 years, and 18-62 years. Craniofacial morphometric cephalometrics were analyzed using Materialise software. Crouzon orbit anteroposterior length was shorter before 6 months (P = 0.021) and remained shorter into adulthood (P < 0.001). Globe projection was greater across all age subgroups (P < 0.001), reaching a peak at 6 months to 2 years (P < 0.001). The increased medial orbital width was the most remarkable and persistent secondary deformity (P < 0.001). The zygoma anterior protrusion was retruded before 6 months of age (P < 0.001), but then improved gradually. The width of maxilla was greater by 24% in the Crouzon cohort (P < 0.001), with a difference of 16% before 6 months (P = 0.024), and was developed earlier than the shortened anteroposterior length. Crouzon high and shallow orbital walls are distinctive. Maxillary widening developed before the malformation of sphenoid. The anteroposterior position of zygoma is likely a principal deformity, rather than a reflection of the intrinsic shape of the bone.
- Cranial Fossa Volume in Differing Subtypes of Apert Syndrome(2019) LU, Xiaona; FORTE, Antonio Jorge; WILSON, Alexander; ALPEROVICH, Michael; STEINBACHER, Derek M.; ALONSO, Nivaldo; PERSING, John A.Background: Based on an established classification system of Apert syndrome subtypes, detailed regional morphology and volume analysis may be useful to provide additional clarification to individual Apert cranial structure characteristics, and treatment planning. Methods: Computed tomography scans of 32 unoperated Apert syndrome and 50 controls were included and subgrouped as: type I, bilateral coronal synostosis; type II, pansynostosis; type III, perpendicular combination synostosis. Three-dimensional analysis of craniometric points was used to define structural components using Materialise Mimics and 3-Matics software. Results: Occipitofrontal circumference of all subtypes of Apert syndrome patients is normal. Intracranial volumes of types I and II were normal, but type III was 20% greater than controls. Middle cranial fossa volume was increased in all 3 types, with the greatest increase in type II (86%). Type II developed a 69% increase in anterior cranial fossa volume, whereas type III had 39% greater posterior cranial fossa volume. Increased cranial fossa depth contributed most to above increased volume. The anteroposterior lengths of middle and posterior cranial fossae were reduced in type I (15% and 17%, respectively). However, only the anterior cranial fossa was significantly shortened in type III. Conclusions: Occipitofrontal circumference and overall intracranial volume is not always consistent in individual subunits of Apert syndrome. Detailed and segmental anterior, middle, and posterior cranial fossae volumes and morphology should be analyzed to see what impact this may have related to surgical planning.
- Brazilian Three-Societal Bi-Annual Meeting: ABCCMF, ABFLP, LATICFA(2019) RAPOSO-AMARAL, Cassio Eduardo; ALONSO, Nivaldo; RAPOSO-AMARAL, Cesar Augusto; FISHER, Mark; BRADLEY, James P.
- Patient-Perceived Barriers to Accessing Cleft Care at a Tertiary Referral Center in Sao Paulo, Brazil(2019) ISE, Ananda; MENEZES, Camila; NETO, Joao Batista; SALUJA, Saurab; AMUNDSON, Julia R.; JENNY, Hillary; MASSENBURG, Ben; CITRON, Isabelle; ALONSO, NivaldoBackground: In low- and middle-income countries, poor access to care can result in delayed surgical repair of orofacial clefts leading to poor functional outcomes. Even in Brazil, an upper middle-income country with free comprehensive cleft care, delayed repair of orofacial clefts commonly occurs. This study aims to assess patient-perceived barriers to cleft care at a referral center in Sao Paulo. Methods: A 29-item questionnaire assessing the barriers to care was administered to 101 consecutive patients (or their guardians) undergoing orofacial cleft surgery in the Plastic Surgery Department in Hospital das Clinicas, in Sao Paulo, Brazil, between February 2016 and January 2017. Results: A total of 54.4% of patients had their first surgery beyond the recommended time frame of 6 months for a cleft lip or cleft lip and palate and 18 months for a cleft palate. There was a greater proportion of isolated cleft palates in the delayed group (66.7% vs 33.3%). Almost all patients had a timely diagnosis, but delays occurred from diagnosis to repair. The mean number of barriers reported for each patient was 3.8. The most frequently cited barriers related to lack of access to care include (1) lack of hospitals available to perform the surgery (54%) and (2) lack of availability of doctors (51%). Conclusion: Delays from diagnosis to treatment result in patients receiving delayed primary repairs. The commonest patient-perceived barriers are related to a lack of access to cleft care, which may represent a lack of awareness of available services.
- Spatial and temporal changes of midface in Apert's syndrome(2019) LU, Xiaona; FORTE, Antonio Jorge; SAWH-MARTINEZ, Rajendra; WU, Robin; CABREJO, Raysa; WILSON, Alexander; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.The dysplastic maxilla and retracted zygoma characterize Apert's syndrome. The relationship between the cranial base and facial development is believed to be influential and substantial. The purpose of this study is to explore the temporal relationships of maldevelopment of these structures to identify potential influence patterns. Fifty-four CT scans (unoperated Apert's, n = 18; control, n = 36) were included and divided into three age subgroups (0-6 months, 6 months-2 years, and 2-6 years). All measurements were analyzed by Materialize software. Cephalometrics relating to midface and cranial base were collected. In anteroposterior direction, prior to 6 months, the zygoma was markedly retruded by 12% in Apert's, followed by persistent retrusive shape into adulthood, averaging 17% shorter compared to controls. The maxillary anteroposterior dimension was 22% shorter than normal before 6 months of age, thereafter, it maintained at least an 18% deficiency into adulthood. In the horizontal direction, the transverse width of the zygoma increased 39% between 6 months and 2 years of age, and it was 14% wider on average overall into adulthood. The maxilla had normal growth in transverse and vertical directions. The zygoma is the most severely deformed anatomic facial structure in early infancy, in both positional relation and geometric shape in Apert's syndrome. This may develop as a 'bridge', influencing the structure, transmitting malformation stresses, caused by premature fused coronal and peri-zygomatic sutures, into facial structures and the maxilla.
- Classification of Subtypes of Apert Syndrome, Based on the Type of Vault Suture Synostosis(2019) LU, Xiaona; SAWH-MARTINEZ, Rajendra; FORTE, Antonio Jorge; WU, Robin; CABREJO, Raysa; WILSON, Alexander; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Background: Apert syndrome patients are different in clinical pathology, including obstructive sleep apnea, cleft palate, and mental deficiency. These functional deficiencies may be due to anatomic deformities, which may be caused by different forms of associated suture fusion. Therefore, a classification system of Apert syndrome based on the type of craniosynostosis pattern might be helpful in determining treatment choices. Methods: CT scans of 31 unoperated Apert syndrome and 51 controls were included and subgrouped as: class I. Bilateral coronal synostosis; class II. Pansynostosis; and class III. Perpendicular combination synostosis: a. unilateral coronal and metopic synostosis; b. sagittal with bilateral/unilateral lambdoid synostosis; and c. others. Results: Class I is the most common (55%) subtype. The cranial base angulation of class I was normal; however, the cranial base angulation on the cranium side of the skull in class II increased 12.16 degrees (P = 0.006), whereas the facial side cranial base angle of class IIIa decreased 4.31 degrees (P = 0.035) over time. The external cranial base linear measurements of class I showed more evident reduction in anterior craniofacial structures than posterior, whereas other subtypes developed more severe shortening in the posterior aspects. Conclusions: Bicoronal synostosis is the most common subtype of Apert syndrome with the normalized cranial base angulation. Combined pansynostosis patients have flatter cranial base, whereas the combined unilateral coronal synostosis have a kyphotic cranial base. Class I has more significant nasopharyngeal airway compromise in a vertical direction, whereas classes II and III have more limited oropharyngeal space.
- 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.
- Airway Analysis in Apert Syndrome(2019) FORTE, Antonio J.; LU, Xiaona; HASHIM, Peter W.; STEINBACHER, Derek M.; ALPEROVICH, Michael; PERSING, John A.; ALONSO, NivaldoBackground: Apert syndrome is frequently combined with respiratory insufficiency, because of the midfacial deformity which, in turn, is influenced by the malformation of the skull base. Respiratory impairment resulting from Apert syndrome is caused by multilevel limitations in airway space. Therefore, this study evaluated the segmented nasopharyngeal and laryngopharyngeal anatomy to clarify subcranial anatomy in children with Apert syndrome and its relevance to clinical management. Methods: Twenty-seven patients (Apert syndrome, n = 10; control, n = 17) were included. All of the computed tomographic scans were obtained from the patients preoperatively, and no patient had confounding disease comorbidity. Computed tomographic scans were analyzed using Surgicase CMF. Craniometric data relating to the midface, airway, and subcranial structures were collected. Statistical significance was determined using t test analysis. Results: Although all of the nasal measurements were consistent with those of the controls, the nasion-to-posterior nasal spine, sphenethmoid-to-posterior nasal spine, sella-to-posterior nasal spine, and basion-to-posterior nasal spine distances were decreased 20 (p < 0.001), 23 (p = 0.001), 29 (p < 0.001), and 22 percent (p < 0.001), respectively. The distance between bilateral gonions and condylions was decreased 17 (p = 0.017) and 18 percent (p = 0.004), respectively. The pharyngeal airway volume was reduced by 40 percent (p = 0.01). Conclusion: The airway compromise seen in patients with Apert syndrome is attributable more to the pharyngeal region than to the nasal cavity, with a gradually worsening trend from the anterior to the posterior airway, resulting in a significantly reduced volume in the hypopharynx.