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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- 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.
- Reduced Three-Dimensional Nasal Airway Volume in Treacher Collins Syndrome and Its Association with Craniofacial Morphology(2015) MA, Xiaoyang; FORTE, Antonio Jorge; BERLIN, Nicholas Lee; ALONSO, Nivaldo; PERSING, John A.; STEINBACHER, Dereck MatthewBackground: Airway insufficiency decreases quality of life and may be life threatening in patients with Treacher Collins syndrome. The authors calculated the three-dimensional nasal airway volume in patients with Treacher Collins syndrome to identify correlations between nasal airway volume and craniofacial morphology and provide guidance for surgical planning. Methods: Thirty nonoperated patients with Treacher Collins syndrome were compared with 35 unaffected age-and gender-matched controls. Anatomic variables of the cranial base, the maxilla complex, and internal diameters of nasal airway were compared between patients and control subjects using three-dimensional craniometric analyses. In the Treacher Collins group, the relation of craniofacial morphology to nasal airway volume was assessed separately. Statistical analyses were performed using independent sample t tests and Pearson correlation coefficient analyses. Results: Nasal airway volume was decreased 38.6 percent in patients with Treacher Collins syndrome relative to controls (p = 0.001). A positive correlation of maxillary position and nasal airway volume was shown in Treacher Collins patients (r = +0.463, p = 0.013). Maxillary, nasal bone, and orbitale width were also positively correlated with nasal airway volume (r = +0.582, p = 0.001; r = +0.408, p = 0.035; and r = +0.677, p < 0.001, respectively). Shortened internal diameters of the nasal airway all positively correlated with nasal airway volume. Conclusions: Nasal airway volume is reduced in patients with Treacher Collins syndrome. Reduced projection of the maxilla and transverse maxillary deficiency are correlated with reduced nasal airway volume and are primarily responsible for obstruction of the nasal airway.
- 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).
- Respective Roles of Craniosynostosis and Syndromic Influences on Cranial Fossa Development(2021) LU, Xiaona; FORTE, Antonio Jorge; WILSON, Alexander T.; PARK, Kitae Eric; ALLAM, Omar; ALPEROVICH, Michael; STEINBACHER, Derek M.; ALONSO, Nivaldo; PERSING, John A.Background: Little is known about the detailed growth of the cranial fossae, even though they provide an important structural connection between the cranial vault and the facial skeleton. This study details the morphologic development of isolated cranial vault synostosis and associated syndromes on cranial fossa development. Methods: A total of 125 computed tomographic scans were included (nonsyndromic bicoronal synostosis, n = 36; Apert syndrome associated with bicoronal synostosis, n = 24; Crouzon syndrome associated with bicoronal synostosis, n = 11; and controls, n = 54). Three-dimensional analyses were produced using Materialise software. Results: The regional anterior and middle cranial fossae volumes of nonsyndromic bicoronal synostosis are characterized by significant increases of 43 percent (p < 0.001) and 60 percent (p < 0.001), respectively, and normal posterior cranial fossa volume. The cranial fossae depths of nonsyndromic bicoronal synostosis were increased, by 37, 42, and 21 percent (all p < 0.001) for anterior, middle, and posterior cranial fossae, respectively, accompanying the shortened cranial fossae lengths. The volume and morphology of all cranial fossae in Apert syndrome nearly paralleled nonsyndromic bicoronal synostosis. However, Crouzon syndrome had reduced depths of cranial fossae, and more restricted fossa volumes than both Apert syndrome and nonsyndromic bicoronal synostosis. Conclusions: Cranial vault suture synostosis is likely to be more influential on cranial fossae development than other associated influences (genetic, morphologic) in Apert and Crouzon syndromes. Isolated Apert syndrome pathogenesis is associated with an elongation of the anterior cranial fossa length in infants, whereas in Crouzon syndrome, there is a tendency to reduce cranial fossa depth, suggesting individual adaptability in cranial fossae development related to vault synostosis.
- 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.
- Influence of Nonsyndromic Bicoronal Synostosis and Syndromic Influences on Orbit and Periorbital Malformation(2022) LU, Xiaona; FORTE, Antonio Jorge; DINIS, Jacob; JUNN, Alexandra; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Background: Oculoorbital disproportion in patients with craniosynostosis has similarities and dissimilarities between syndromic and nonsyndromic cases. The authors hypothesized that these two conditions have specific individual influences as they relate to development of the orbital and periorbital skeletons. Methods: A total of 133 preoperative computed tomography scans (nonsyndromic bicoronal synostosis, n = 38; Apert syndrome bicoronal synostosis subtype, n = 33; Crouzon syndrome bicoronal synostosis subtype, n = 10; controls, n = 52) were included. Craniometric and volumetric analyses related to the orbit and periorbital anatomy were performed. Results: Orbital cavity volume was mildly restricted in nonsyndromic bicoronal synostosis (7 percent, p = 0.147), but more so in Apert and Crouzon syndromes [17 percent (p = 0.002) and 21 percent (p = 0.005), respectively]. The sphenoid side angle in Apert syndrome was wider than when compared to Crouzon syndrome (p = 0.043). The ethmoid side angle in Apert patients, however, was narrower (p = 0.066) than that in Crouzon patients. Maxilla anteroposterior length was more restricted in Apert syndrome than Crouzon syndrome (21 percent, p = 0.003) and nonsyndromic cases (26 percent, p < 0.001). The posterior nasal spine position was retruded in Crouzon syndrome (39 percent, p < 0.001), yet the anterior nasal spine position was similar in Apert and Crouzon syndromes. Conclusions: Orbit and periorbital malformation in syndromic craniosynostosis is likely the combined influence of syndromic influences and premature suture fusion. Apert syndrome expanded the anteriorly contoured lateral orbital wall associated with bicoronal synostosis, whereas Crouzon syndrome had more infraorbital rim retrusion, resulting in more severe exorbitism. Apert syndrome developed maxillary hypoplasia, in addition to the maxillary retrusion, observed in Crouzon syndrome and nonsyndromic bicoronal synostosis patients.
- Association of Regional Cranial Base Deformity and Ultimate Structure in Crouzon Syndrome(2019) LU, Xiaona; FORTE, Antonio Jorge; SAWH-MARTINEZ, Rajendra; WU, Robin; CABREJO, Raysa; STEINBACHER, Derek M.; ALPEROVICH, Michael; ALONSO, Nivaldo; PERSING, John A.Background: Considerable craniofacial features of Crouzon syndrome are attributed to the dysmorphology of the cranial base. As cephalometric studies have focused mainly on the facial deformity, rather than the cranial base, the underlying cause of deformity is not as well understood. Therefore, the authors compared the cranial base development of Crouzon syndrome to controls to trace the timing of deformity in the cranial base and face, to analyze their temporal correlation. Methods: Ninety computed tomographic scans were included (Crouzon, n = 36; controls, n = 54) and divided into five age subgroups. Craniofacial cephalometric measurements were analyzed by Materialise software. Results: The overall cranial base length in Crouzon syndrome compared with controls decreased 8 percent (p = 0.014) on average. The posterior cranial fossa shortening accounted for most of this reduction. The cranial base displaced with the distances from basion, sella, and ethmosphenoid to posterior nasal spine shortened by 21%, 18%, and 16%, respectively (all p < 0.01) during life. Although the cranial base angle on intracranial surface remains normal, the angles on facial surface narrowed were reduced. Conclusions: The cranial base deformity of Crouzon syndrome consists of the whole skull base and particularly anterior skull base shortening early, leading to a compensatory widened anterior skull base. However, when this widening did not compensate fully for the rapid enlargement of the brain, the posterior skull base displaced inferiorly and became kyphotic. The cranial base deformity develops sequentially anterior to posterior in a probable cascade of influence pattern.
- Analysis of Midface Retrusion in Crouzon and Apert Syndromes(2014) FORTE, Antonio Jorge; ALONSO, Nivaldo; PERSING, John A.; PFAFF, Miles J.; BROOKS, Eric D.; STEINBACHER, Derek M.Background: Midface retrusion is the hallmark of the syndromic dysostoses (i.e., Crouzon and Apert). Lack of forward projection and/or structural deficiency could be responsible, but neither has been adequately assessed three-dimensionally. The authors examined both the cranial base/facial interface and the midface volume to provide an understanding of the etiopathogenesis of midface deficiency. Methods: Children with computed tomographic scans in the absence of any surgical intervention were included. Demographic information was recorded for three groups: Apert, Crouzon, and control. Scans were digitized and manipulated using Materialise software (Surgicase CMF). Craniometric data relating to the midface and sphenoid were collected. Volumetric assessment of the midface was tabulated. Statistical analysis was performed using the t test. Results: Thirty-six scans were included (control, n = 17; Crouzon/Apert, n = 19). All children were in the early mixed dentition stage. The anterior cranial fossa proved to be shorter and wider in Crouzon/Apert patients compared with controls. The cranial base angles (N-S-BA, N-S-SO, N-SO-BA, S-SO-BA, and N-S-AR) were not statistically different across the groups. The Crouzon/Apert group showed angles more obtuse between the greater wings of the sphenoid, and more obtuse (more splayed) between the pterygoid plates. Nasion-sellapterygomaxillary fissure angle was more obtuse (flatter) in the Crouzon/Apert group. There was no volumetric difference in the maxilla, zygoma, and sphenoid comparing the Crouzon/Apert group to controls. Conclusions: Midface retrusion in the Crouzon/Apert group is associated with altered sphenoid morphology (widened and retruded pterygoid plates), with a flatter and wider maxilla, suggesting diminished growth inferiorly and anteriorly. There is no volumetric deficiency in Crouzon/Apert patients compared with controls.
- Cadaveric Study of Breast Measurements during Augmentation with Implants(2015) FORTE, Antonio Jorge; BARBOSA, Marco Polo; PERSING, John Arthur; ALONSO, Nivaldo; BERLIN, Nicholas; BROER, Niclas; NARAYAN, Deepak; KWEI, StephanieBackground: The goal of this study was to compare immediate changes in breast shape and nipple position using different implant shapes and volumes, with variable release of the pectoralis major muscle in fresh cadavers. Methods: Seventeen fresh cadaveric breasts were analyzed. Six different augmentation procedures were performed, including pocket dissection in the sub-muscular and subglandular planes, and partial and full release of the pectoralis major muscle insertion. Round and contoured implant volumes of 200, 300, 400, 500, and 600 ml were used, resulting in a total of 30 procedures per breast. Results: Projection was greater when subjects received contoured implants versus round implants in all volumes both in submuscular and in subglandular pockets (p < 0.001). For implants larger than 200 ml, projection was greater when a subglandular pocket was chosen (p < 0.02), for both round and contoured implants. Nipple-to-inframammary fold distance was increased with contoured implants compared with round implants in both subglandular and submuscular pockets for all implant volumes (p < 0.05). Conclusions: Implant shape, volume, and pocket location influence projection, causing it to increase in a linear fashion. Partial pectoralis major release seems to affect projection only for small volumes, but does not influence nipple position in the immediate setting. As projection increases with augmentation volume, cephalad movement of the nipple is produced by a relative increase in nipple-to-inframammary fold distance compared with the midclavicular point-to-nipple distance in our cadaveric sample.