Long-Term Three-Dimensional Morphometric Outcome Study of Nasal Bone in Cleft Patients.

Cleft lip nose deformities are characterized by underlying features in the bony skeleton as well as the soft tissues; however, no previous study has focused on the evaluation of the nasal bone. The aim of this study was to compare nasal bone features among adult patients with unilateral cleft lip with or without cleft palate, those with bilateral cleft lip and palate, and controls. Included in this retrospective study were patients aged ≥16 years with nonsyndromic cleft who underwent long-term orthodontic treatment and controls aged 18-45 years who underwent surgery for jaw deformities at Keio University Hospital. Piriform width, nasal width, and nasomaxillary angle values measured on CT were compared among the groups using the Wilcoxon rank sum test. Nine patients had unilateral cleft lip and alveolar cleft, 19 had unilateral cleft lip and cleft palate, and 14 had bilateral cleft lip and palate (BCLCP). There were 18 controls. Mean piriform width and mean nasomaxillary angle were significantly greater in the BCLCP group than the control group (20.1±2.54 mm versus 18.8±1.35 mm, P<0.05; and 105.8±8.13 degrees versus 100.4±7.95 degrees, P<0.05, respectively). There was no significant difference in mean nasal width among the groups. Nasal bone morphology was not affected by initial cleft lip alone or by the presence or absence of cleft palate. Patients with bilateral cleft lip and palate have a wider and lower nose than those without cleft deformity and might benefit more from reduction of the bony nasal width than from treatment of the soft tissues.

Influence of the Number of Revision Surgeries and Nasal Symmetry After Final Rhinoplasty for Patients With Cleft Lip.

The effects of operative intervention on vertical nasal growth in patients with unilateral cleft lips (CLs) are well described. However, the factors influencing nasal symmetry have not been sufficiently evaluated. Therefore, this study aimed to study the factors that cause difficulties in obtaining nasal symmetry postoperatively in patients with CLs. We conducted a retrospective analysis using data from patients with CLs who underwent a series of treatments at Keio University Hospital from 1990 to 2000. We collected data on the patients' sex, cleft type, number and time of revision surgery, palatal fistula incidence, and history of the pharyngeal flap and orthognathic surgery. Nasal symmetry was analyzed as the symmetrical ratio after the final touch-up surgery, and multivariate analysis was conducted using binary logistic regression to determine the factors affecting nasal symmetry. This study included 89 patients with unilateral CL. Multivariate analysis revealed that complete cleft lip and palate ( P < 0.05, odds ratio = 4.37) and repeated revision surgery ( P < 0.05, odds ratio = 9.28) were significant predictors of the final nasal symmetry. Our study showed that cleft type and the number of revision surgeries were identified as important factors for obtaining nasal symmetry after final touch-up rhinoplasty. Revision surgery may be necessary to relieve patients' psychological stress due to nasal deformity, suggesting that this dilemma needs to be overcome.

Nasal tip surgery for cleft nose in Asians.

"Collapsed nasal tip," one of the most characteristic features of cleft lip nose, resembles the effect of pushing the nose tip with a finger and is especially noticeable among Asians. The authors examined a rhinoplasty technique for improving collapsed nasal tip. Using an intercartilaginous incision, the distal nasal framework, including the alar cartilages, and the caudal septum were widely exposed. A septal extension graft was fixed to the caudal septum, and the alar cartilages were precisely sutured to the extension graft using markings transferred to the extension graft. This procedure was applied to 15 Asian rhinoplasties, with all patients having substantial improvement in the shape of their nasal tip. Comparing those with and without a history of rhinoplasty, effecting a projection of the nasal tip was more difficult in patients with a history of previous rhinoplasties. The advantages of this technique include inconspicuous scarring and versatility in the modification of the nasal tip. Rhinoplasty during the growth period should be planned with consideration of future augmentation rhinoplasties.

Classification of congenital midline upper lip sinuses: a case report and review of the literature.

BACKGROUND: We recently encountered a case of a midline upper lip sinus, one of the rarest congenital lip sinuses. Several embryological hypotheses have been proposed regarding the etiology of this rare disease, but it remains obscure. METHODS: We reviewed all cases of upper lip sinus reported in the English language through 2011, and classified them into three types according to accompanying anomalies and the site of the fistula. RESULTS: Twenty-eight studies involving 31 cases were reviewed and classified. A type I sinus was a midline sinus without accompanying anomalies. There were 13 such cases, with a female predilection. Type II sinuses were midline sinuses with accompanying anomalies, and there were nine such cases. Type III sinuses were lateral sinuses with or without accompanying anomalies; there were nine cases. CONCLUSIONS: Our classification scheme is not only convenient for clinical application, but also reflects the embryological process responsible for congenital lip sinuses.

Evaluation of bone volume after secondary bone grafting in unilateral alveolar cleft using computer-aided engineering.

The purpose of this study was to evaluate the initial defect and the outcome of bone grafts for unilateral alveolar cleft. To determine the absorption of the bone graft in patients with unilateral cleft, computer-aided engineering (CAE) with multi-detector row computed tomography (MDCT) was used. MDCT scans of 29 patients were taken immediately preoperatively and at 1 month and 6 months postoperatively. The patients underwent bone grafting between 8 and 14 years of age using iliac crest bone grafts. Three-dimensional models were created in each period, and the defect at the alveolar cleft and volume of the bone graft were determined in each patient using CAE. Cleft volume and success of alveolar bone grafting were significantly correlated (P < .01). Alveolar clefts with cleft palate required more bone volume than those without cleft palate (P < .01), but the resorption rate did not significantly differ between alveolar clefts with and without cleft palate (0.48 ± 0.14 and 0.49 ± 0.18, respectively; P = .93). In conclusion, three-dimensional reconstruction of bone grafts using CAE based on MDCT provides a valuable objective assessment of graft volume.

Involvement of the sphenosquamosal suture for unilateral coronal synostosis.

The etiology of the clinical entity commonly known as unilateral coronal synostosis is often described as the unilateral fusion of the coronal ring. However, recent theories have poorly explained the basis of the deformities associated with unilateral coronal synostosis. We retrospectively analyzed computed tomographic data sets from 18 patients who presented with unilateral coronal synostosis and arrived at our hospital between 1985 and 2010. Using three-dimensional reconstructions of the computed tomographic images, analyses of the cranial base and measurements of each cranial bone were performed. As a result, the ipsilateral and contralateral basion-clinoid-pterion angles did not differ significantly (P = 0.49) and were almost identical in each case. However, the ipsilateral basion-partis-petrosae angle was wider than the corresponding contralateral angle (P < 0.001). In addition, the ipsilateral nasion-clinoid-pterion angle and the sphenoid, zygomatic, and temporal bones on the ipsilateral side were significantly shorter than those on the contralateral side (P < 0.001). Based on a shortening ratio, the sphenoid bone was smaller (42.0% ± 10.9%) than the temporal (68.9% ± 7.58%) and zygomatic bones (71.1% ± 8.38%). This difference was significant (P < 0.001). In conclusion, restricted growth potential of the central portion of the ipsilateral sphenoid bone was identified. We propose that the coronal ring, which includes the frontoparietal and frontosphenoidal sutures, and the sphenosquamosal suture are involved in unilateral coronal synostosis. Using our findings and the theory of Delashaw et al, the deformity observed in unilateral coronal synostosis can be explained more adequately and/or completely.

New classification scheme of proboscis lateralis based on a review of 50 cases.

BACKGROUND: Among congenital nasal deformities, proboscis lateralis is one of the rarest. Boo-Chai classified proboscis lateralis into four groups. Recently, we encountered a new case of proboscis lateralis with median cleft lip. We noticed that this classification had not been considered according to convalescence and embryologics, and further refinement seemed to be needed. METHODS: We reviewed all cases of proboscis lateralis reported in English through 2009 and classified them by intercanthal distance. RESULTS: A total of 34 studies involving 50 cases were reviewed. Six cases were identified as having normal intercanthal distance. Three of them presented nose abnormalities and fit Boo-Chai group II category. The other three were consistent with group I. Hypertelorism was observed in 27 cases and was further divided into two groups based on the occurrence of a frontal encephalocele. Seventeen cases without a frontal encephalocele were compatible with Boo-Chai groups III and IV. The other 10 cases associated with a visible encephalocele had encephalopathy; most died at an early age, and long-term survival cases suffered developmental delay and mental retardation. Seventeen cases were defined as hypotelorism, and all cases also presented as holoprosencephaly. CONCLUSIONS: The redefined classification contains two new groups: group V as hypertelorism with encephalocele and group VI as hypotelorism. A new classification scheme is proposed as not only convenient for clinical application but also embryologically accurate.

The role of surgeon's learning on the outcomes of alveolar bone graft for cleft repair.

BACKGROUND AND PURPOSE: Teaching cleft repair in the operating room may not sufficiently prepare craniofacial residents to perform the procedure self-reliantly. This study aimed to assess the influence of surgeons' experience level on the operative time and graft survival ratio after alveolar bone grafts for cleft repair. SUBJECTS AND METHODS: This was a retrospective review of 100 consecutive alveolar bone graft patients treated for unilateral alveolar cleft by one craniofacial surgeon between 2012 and 2019. An alveolar bone graft from the iliac bone was performed using the lateral sliding flap. Sex, age, cleft width, cleft defect volume, and operative time were recorded, and the 1-year postoperative graft survival ratio was calculated. Multiple regression analysis was performed to identify factors that affect the operative time and survival ratio. RESULTS: Factors affecting the operative time were the experience level of the surgeon and the presence of a cleft palate. Factors affecting the graft survival ratio were the cleft defect volume and experience level of the surgeon. In cleft lip and alveolus, the survival ratio was constant, and the operative time stabilised after approximately 20 cases. In cleft lip and palate, more experience was required to master the technique, and the operative time and survival ratio were stabilised only after approximately 40 cases. CONCLUSION: Surgeons' experience level influenced the outcomes of alveolar bone grafting. Although surgical training is currently undergoing a paradigm shift from on-the-job training to simulation-based training, clinical experience is critical to be self-sufficient.

Reconstruction of the scalp with a calvarial defect.

PURPOSE: To review our clinical cases and devise a protocol for selecting the best operative methods to reconstruct the scalp with a calvarial defect. METHODS: We reviewed the original disease, the areas and depths of the scalp and calvarial defects, the methods of reconstruction, and complications in 20 patients. RESULTS: The defect was caused by secondary cranial infection following decompressive craniectomy for intracranial hemorrhage (ICH) in 11 patients; extensive removal of the scalp and calvaria for resection of a malignant tumor in 6 patients; and by secondary cranial infection following removal of a malignant tumor in 3 patients. Cranial infection was frequently associated with abscess formation around the fixation screws and plates, suggesting that artificial materials induced the infection. We reconstructed the defect using free flaps in 15 patients and using local flaps in 5 patients. CONCLUSIONS: When restoring the calvaria in the primary operation, the use of metal screws and plates should be minimized to prevent cranial infection and subsequent scalp and calvaria defects. Local flaps are appropriate for reconstructing relatively small defects (<20 cm(2)), whereas free flaps are better for reconstructing relatively large defects (>25 cm(2)).

Palatoplasty for bilateral oblique cleft of the soft palate accompanied by Tessier number 5·7 cleft.

Craniofacial cleft is a rare congenital deformity in which there are fissures of a facial structure classified by Tessier. A palatoplasty to reconstruct the muscle sling and to close the cleft of the velum was performed. Acceptable postoperative appearance of the velum was seen after 6 months. Although further follow-up is still needed for velopharyngeal function, this case report provides details of the anatomical deformities and our surgical approach to this atypical bilateral cleft palate.

Biomechanical analysis of the effect of intracranial pressure on the orbital distances in trigonocephaly.

OBJECTIVE: This biomechanical study aims to elucidate differences in how skulls with trigonocephaly, normal skulls, and postoperative trigonocephalic skulls respond to intracranial pressure and how this affects the orbital distances. MATERIALS AND METHODS: For 10 patients with trigonocephaly (8.2 ± 4.5 months), simulation models were produced based on the computed tomographic data of the skulls. These models were categorized as the Trigono group. For each model, a 15-mm Hg pressure was applied to the neurocranium to simulate the intracranial pressure. The interorbital distances expanded in response to the applied pressure. The amount of the change in the orbital distance was calculated using finite element analysis. The same processes were repeated for 10 models simulating normal skulls (the Control group) and postoperative trigonocephalic skulls (the Remodeled group). The changes in the orbital distance were compared among the three groups. RESULTS: The changes in the orbital distance were significantly smaller for the Trigono group than for the Control group. However, changes were significantly greater for the Remodeled group than for the Control group. CONCLUSION: The expansion of interorbital distances in response to the cranial pressure is restricted in skulls with trigonocephaly. This restriction is eliminated by performing remodeling of the skull. These findings explain why spontaneous correction of hypotelorism occurs postoperatively in trigonocephaly.

Interaction of hydraulic and buckling mechanisms in blowout fractures.

The etiology of blowout fractures is generally attributed to 2 mechanisms--increase in the pressure of the orbital contents (the hydraulic mechanism) and direct transmission of impacts on the orbital walls (the buckling mechanism). The present study aims to elucidate whether or not an interaction exists between these 2 mechanisms. We performed a simulation experiment using 10 Computer-Aided-Design skull models. We applied destructive energy to the orbits of the 10 models in 3 different ways. First, to simulate pure hydraulic mechanism, energy was applied solely on the internal walls of the orbit. Second, to simulate pure buckling mechanism, energy was applied solely on the inferior rim of the orbit. Third, to simulate the combined effect of the hydraulic and buckling mechanisms, energy was applied both on the internal wall of the orbit and inferior rim of the orbit. After applying the energy, we calculated the areas of the regions where fracture occurred in the models. Thereafter, we compared the areas among the 3 energy application patterns. When the hydraulic and buckling mechanisms work simultaneously, fracture occurs on wider areas of the orbital walls than when each of these mechanisms works separately. The hydraulic and buckling mechanisms interact, enhancing each other's effect. This information should be taken into consideration when we examine patients in whom blowout fracture is suspected.

A rare case of proboscis lateralis with median cleft lip.

A very rare case of proboscis lateralis is reported. This case is different from previously reported cases due to proboscis lateralis, single nostril, loss of columella, and median cleft lip without holoprosencephaly. In addition, this is considered the first surviving individual with proboscis lateralis accompanied by median cleft lip.

A biomechanical study on the effect of premature fusion of the frontosphenoidal suture on orbit asymmetry in unilateral coronal synostosis.

OBJECTIVE: The coronal ring of patients with unilateral coronal synostosis (UCS) presents premature fusion. This study aims to elucidate whether or not the dynamic behavior of the orbit in response to intracranial pressure (ICP) differs between patients in whom the premature fusion exists only in the frontoparietal suture (FPS) and those in whom the premature fusion extends to the frontosphenoidal suture (FSS). METHODS: A total of 15 UCS patients were included in the present study. Patients in whom premature fusion was seen inside the FPS and those in whom premature fusion extended to the FSS were categorized as FP Only (4.2 +/- 1.4 m/o) and FP + FS groups (4.6 +/- 2.2 m/o), respectively. On the basis of computed tomography (CT) data, computer-aided design models were produced. Pressure of 15 mm Hg was applied to the neurocranium of each skull model to simulate ICP. Using the finite element method, the displacements presented by each model's orbits were calculated. Displacements of the two groups were compared. RESULTS: The orbit demonstrated greater displacement in the FP Only group than in the FP + FS group, suggesting that premature closure of the FSS disturbs growth of the orbit in response to ICP. CONCLUSION: In performing surgical treatment for UCS, the degree of fusion that the FSS presents should be evaluated carefully. In cases in which the FSS presents premature fusion, it is recommended to release the fusion at an early stage of cranial growth to improve the appearance of the orbital region.

Biomechanical evaluation of implant placement in the reconstructed mandible.

PURPOSE: Following resection of malignant tumors from the mandible, immediate reconstruction of the discontinuous jaw is commonly performed. The present study aims to define the risks associated with dynamic loading of the reconstructed mandible. MATERIALS AND METHODS: Computer-aided design simulations of eight mandibles were produced and termed normal models. The normal models were then modified by removing part of the right body and restoring the defects with bone from the rib or fibula. These modified models were termed reconstructed models. Thereafter, an implant was embedded in the first molar region of the left side for all models. Using finite element analysis, the stresses occurring at the implant-bone interface with simulated mastication were calculated. The Wilcoxon signed rank test was applied to compare the magnitudes of stresses in both models. RESULTS: In terms of the stress exerted at the implant-bone interface during mastication, the normal models and the reconstructed models showed no significant differences (P > .05). CONCLUSION: Placement of an implant on the nonreconstructed side following partial resection and mandibular reconstruction presents no significant risk.

A new method to quantify subtle morphological deformities in nasal profile curvatures and its application for analysis of unilateral cleft lip noses.

OBJECTIVE: The authors conducted the present study to elucidate what elements characterize the nasal profiles of patients with unilateral cleft lips (CLs). MATERIALS AND METHODS: A total of 40 Japanese unilateral CL patients were studied. For each patient, the nasal profile curve was traced on three-dimensional computer tomography image. Then four points were marked on the contour. The points were NAS (Nasion), MAP (the Most Anterior Point on the nasal profile curve), GPRN (the Genuine Pronasale: the point on the nasal curve at which the curve protrudes most), and SBN (Subnasale: the point at the columellar base). Using specially designed software, the distances between these marking points were measured along the nasal profile curve. RESULTS: In CL patients, the distance between the MAP and GPRN is longer, and the GPRN is located more inferiorly than in non-cleft persons. CONCLUSION: The nasal tip tends to become round and to droop in unilateral CL patients. In order to avoid this deformity pattern, the nasal tip should be reshaped to present a sharper curvature and corrected superiorly.

Appropriate diameter for screws to fix the maxilla following Le Fort I osteotomy: an investigation utilizing finite element analysis.

BACKGROUND: After Le Fort I osteotomy, there is sometimes a secondary deformity (relapse), with the lower segment deviating from the intraoperatively fixed position. It is hyopothesized that the structural stability of the reconstructed maxilla is affected by the diameter of the fixation screws. The present study aims to elucidate the relationship between the diameters of the screws and the structural stability of the maxilla after Le Fort I osteotomy. METHODS: 3D models were produced on a workstation from 20 dry skulls and a Le Fort I operation was simulated on them. The upper and lower segments of the divided maxilla in each of the 20 models were connected using four plates and 16 screws. Five different diameters of the fixation screws were tested. Thus altogether 100 models were produced. A 180N load was applied to the molar region for each model. Using finite element analysis, the resultant stresses and deviations of the lower segments were calculated. Finally, referring to these values, the relationships between screw diameters and stability of the lower segment were evaluated. RESULT: The stability of the lower segment was greatest when the diameter of the fixation screws was equal to the thickness of the bone at each fixation site. CONCLUSION: In performing Le Fort I osteotomy, it is recommended that bone thickness is measured at each fixation site in advance, and the diameter of the fixation screws matched accordingly; thereby optimum stability of the reconstructed maxilla can be anticipated.

A comparative study of most suitable miniplate fixation for mandibular symphysis fracture using a finite element model.

The purpose of this study is to determine the most stable fixation method for mandibular symphysis fractures by comparing the mechanical characteristics of models fixed at different positions with different numbers of plates. Fractures were generated in 3-dimensional finite element models, and were fixed with a single miniplate, parallel double miniplates, or perpendicular double miniplates. A 300 N perpendicular load was then applied on the left molar region, and a finite element analysis was performed. We compared vertical gaps between the fractured surfaces, maximum stress within the screw/plating system, and maximum stress around screw holes in the bone. Compared to the single miniplate, both the parallel and perpendicular double miniplates demonstrated significantly less stress in the screw/plating system and screw holes in the bone. In addition, the perpendicular double miniplateshad significantly smaller vertical gaps between fracture surfaces when compared to the single miniplate. Comparing parallel and perpendicular double miniplate fixations, less stress was found around the screw holes of the perpendicular miniplate models than those of the parallel miniplatemodels. There were no differences in vertical gaps or maximum stress within the screw/plating systems between the 2 double miniplate fixations. These results suggest that perpendicular double miniplate fixation is more suitable for fixing mandibular symphysis fractures.

Adaquate fixation of plates for stability during mandibular reconstruction.

PURPOSE: To determine the most appropriate plate fixation for dispersing the stress around screws in mandibular reconstruction. MATERIAL AND METHODS: Forty-eight three-dimensional reconstructed mandibular models with Central (C) or right Lateral (L) defects were created and divided into three groups, fixed with: (1) two screws on each side, (2) three screws on the left side with the third (middle one) located distally, or (3) three screws on the left side with the third (middle one) located proximally. A 300N vertical load was applied to the left molar region. The maximum stress was calculated using a finite element method and statistically evaluated. RESULTS: Stress was concentrated around the screw at the distal end of the mandibular halves on the loaded side ('crucial screw'). For the C defect, stress concentrated around the 'crucial screw' was greater when there were only two screws for fixation (20.55MPa) than when there were three screws (16.17MPa; p=0.022). No significant difference was found between the two groups with three screws for fixation. For the L defect on the other hand, stress on the 'crucial screw' was relatively greater when there were three screws for fixation (18.9MPa) than when there were only two screws for (12.83MPa; p=0.051). No significant difference was found between the two groups with three screws for fixation. As for the reconstruction plate, the stresses on the plates were not different among the various screw groups for fixation nor among the C and L defects. CONCLUSION: This paradoxical result is explained by plate bowing. Thus in large defects screw positions should take into consideration the potential for plate bowing.