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
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- Cranial Fossa Volume and Morphology Development in Apert Syndrome(2020) LU, Xiaona; FORTE, Antonio Jorge; WILSON, Alexander; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Background: Apert syndrome causes normal or enlarged intracranial volume overall as patients grow. This study aimed to trace the segmental anterior, middle, and posterior cranial fossae volume and structural morphology in these patients, to help discern a more focused and individualized surgical treatment plan for patients with Apert syndrome. Methods: This study included 82 preoperative computed tomographic scans (Apert, n = 32; control, n = 50) divided into five age-related subgroups. The scans were measured using image processing and three-dimensional modeling software. Results: The middle cranial fossa volume was increased and was the earliest change noted. It was increased by 45 percent (p = 0.023) compared with controls before 6 months of age and remained increased into adulthood (161 percent, p = 0.016), with gradually increasing severity. The anterior and posterior cranial fossae volumes also increased, by 35 percent (p = 0.032) and 39 percent (p = 0.007), respectively. Increased depth of cranial fossae contributed most to the increase in volumes of patients with Apert syndrome, with correlation coefficients of 0.799, 0.908, and 0.888 for anterior, middle, and posterior cranial fossa, respectively. The intracranial volume was increased 12 percent (p = 0.098) across the entire test age range (0 to 26 years old), but only had statistical significance during the age range of 6 to 18 years (22 percent, p = 0.001). Conclusions: Malformation of the middle cranial fossa is an early, perhaps the initial, pivotal cranial morphologic change in Apert syndrome. Increased cranial fossae depth is an inherent characteristic of the maldevelopment. Normalization of cranial volume and circumference overall may not achieve a normal skull structure, as it does not correct regional craniocerebral disproportion.
- What Is the Difference in Cranial Base Morphology in Isolated and Syndromic Bicoronal Synostosis?(2020) LU, Xiaona; FORTE, Antonio Jorge; WILSON, Alexander T.; PARK, Kitae Eric; ALLAM, Omar; MOZAFFARI, Mohammad Ali; ALPEROVICH, Michael; STEINBACHER, Derek M.; ALONSO, Nivaldo; PERSING, John A.Background: The association of isolated craniosynostosis and the influence of syndromic forms confound the understanding of craniofacial morphologic development. This study attempts to clarify the individual influences of isolated bicoronal synostosis, Apert syndrome, and Crouzon syndromes on skull base morphology. Methods:: One hundred seventeen computed tomographic scans were included (nonsyndromic bicoronal synostosis,n= 36; Apert syndrome with bicoronal synostosis,n= 25; Crouzon syndrome with bicoronal synostosis,n= 11; controls,n= 45). Cephalometric measurements were analyzed using Materialise software. Results: Nonsyndromic bicoronal synostosis patients developed a shortened cranial base length, with a significantly shortened distance between nasion and sella (p= 0.005). The cranial base angles of nonsyndromic bicoronal synostosis in both the cranial side (N-S-BA) and facial side (N-SO-BA) increased significantly, by 17.04 degrees (p <0.001) and 11.75 degrees (p <0.001), respectively. However, both the N-S-BA and N-SO-BA angles of Apert syndrome and Crouzon syndrome were narrowed more than that of nonsyndromic bicoronal synostosis [by 12.11 degrees (p <0.001) and 12.44 degrees (p <0.001), respectively, in Apert syndrome; and by 11.66 degrees (p= 0.007) and 13.71 degrees (p= 0.007), respectively, in Crouzon syndrome]. However, there is no statistically significant difference of these two angles between Apert syndrome and Crouzon syndrome, when they were only associated with bicoronal synostosis. Contrary to the relatively normal subcranial space of nonsyndromic bicoronal synostosis, both Apert and Crouzon syndromes developed a reduced subcranial space. Conclusions: Isolated bicoronal synostosis resulted in a flattened cranial base, whereas Apert syndrome and Crouzon syndrome developed a normal cranial base angle when only associated with bicoronal synostosis. The syndromic skulls had additional significantly reduced subcranial space.
- Orbital and Periorbital Dysmorphology in Untreated Pfeiffer Syndrome(2022) LU, Xiaona; FORTE, Antonio Jorge; ALLAM, Omar; PARK, Kitae Eric; WILSON, Alexander; ALPEROVICH, Michael; STEINBACHER, Derek M.; TONELLO, Cristiano; ALONSO, Nivaldo; PERSING, John A.Background: Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear. Methods: Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software. Results: Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001). Conclusions: Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma).
- Orbital Dysmorphology in Untreated Children with Crouzon and Apert Syndromes(2015) FORTE, Antonio Jorge; STEINBACHER, Derek M.; PERSING, John A.; BROOKS, Eric D.; ANDREW, Tom W.; ALONSO, NivaldoBackground: Orbital dysmorphology and midface retrusion are the hallmarks of Crouzon and Apert syndromes. The precise nature of this deficiency is not known. Methods: Untreated Crouzon and Apert syndrome patients and age- and sex-matched controls were included. Computed tomographic scans were digitized and reconstructed. Craniometric and volumetric data relating to the orbit were collected. Results: Thirty-one scans were included (control, n = 12; Crouzon; n = 9; Apert, n = 10). The mean age of the Apert group was 5.31 5 years; Crouzon, 5.77 +/- 2.7 years; and control, 6.4 +/- 3.6 years. The bony orbit length was 12 percent shorter in Apert (p = 0.004) and 17 percent shorter in the Crouzon group when compared to controls (p < 0.0001). The bony orbital volume was 21 percent smaller in the Apert children (p = 0.0006) and 23 percent smaller in Crouzon when compared to controls (p = 0.003). Globe volume was 15 percent larger in Apert (p = 0.008) and 36 percent larger in the Crouzon group when compared to controls (p < 0.0001). Orbital soft-tissue volume was 19 percent less in the Apert group (p = 0.004) and 29 percent less in the Crouzon group (p = 0.001) when compared to controls. Conclusions: A shortened bony orbit, decreased orbital and orbital soft-tissue volumes, and an increased volume of the globe were found in both conditions. Despite normal volume of the overall orbital contents, the contents are altered, and the bony orbit is shorter and holds less volume.