ABSTRACT
Objective@#To establish finite element models of skull, fronto-orbital advancement and fronto-orbital distraction osteogenesis of craniosynostosis, to analyze the mechanical characteristics of skull base and fronto-orbital operation area, so as to guide the later application of tractors.@*Methods@#One 6-year-old male patient with unilateral coronal synostosis was enrolled in October 2015. Three-dimensional (3D) computed tomography (CT) scan of skull was performed. DICOM data was imported into Mimics 17.0 for contour extraction and cranial 3D reconstruction. The skull model was processed by Mimics, Geomagic Studio 12.0, Hypermesh 12.0 and other software to establish a three-dimensional finite element model. The unilateral and bilateral fronto-orbital anterior osteotomy models were simulated respectively. The mechanical analysis was performed at point A in forehead area and point B in temporal area. Three different groups of traction forces were loaded: (1) 50 Newton for point A, 50 Newton for point B; (2) 80 Newton for point A and 50 Newton for point B; (3) 100 Newton for point A and 50 Newton for point B, to obtain the optimized traction force.@*Results@#Stress analysis was performed on established cranial finite element model, as well as unilateral and bilateral fronto-orbital advancement procedures. The stress distribution of the anterior and middle cranial fossae was found to be concentrated. After unilateral fronto-orbital advancement, the stress of anterior cranial fossa, especially the affected side, was decreased. The stress on both side in anterior cranial fossa was decreased after bilateral fronto-orbital advancement. After force was applied to point A and point B, the optimum deviation result at supraorbital notch point, midpoint of supraorbital margin, frontal temporal point and frontal zygomatic suture point in 3D (Deviation result of X value: -29.4%, -20.5%, -8.6%, -9.3%; Deviation result of Y value: 20.9%, 31.5%, 73.0%, 539.4%; Deviation result of Z value: 4.4%, 1.9%, 0.1%, 11.8%) demonstrated the application of traction force can inwardly, downwardly and forwardly move the bone flap. The optimized traction was 80 Newton at point A and 50 Newton at point B by preliminary assessment.@*Conclusions@#The finite element analysis of the fronto-orbital advancement can be used for more accurate preoperative simulation, to clarify the influence of fronto-orbital advancement on craniofacial morphology and development, as well as skull base. It also facilitates surgical decision and predicts the postoperative distraction vectors.
ABSTRACT
Objective@#To investigate a new method to treat unilateral coronal synostosis.@*Methods@#2 cm-wide osteotomy was performed over the fused unilateral coronal suture.Oblique osteotomy was performed along the supraorbital rim to do a frontal suture of the glabella (patients less than one year old) or on the opposite side of the supraorbital rim (patients over one year old) after performing a suturectomy of the effected coronal suture. Two internal distraction devices were subsequently placed across the osteotomized, fused coronal suture. At the top of the unfused metopic suture, bring two holes and fixing with 4-0 absorbable suture.Finally, the cranium pieces were divided into 2 pieces and placed in the middle of the frontal bone using biological glue or titanium screws. Five days after the operation, a 0.6 mm distraction was performed twice per day. The distraction was removed 6 months after distraction reaching 30—60 mm.@*Results@#Internal distraction osteogenesis with supraorbital oblique osteotomy was performed in eleven patients suffering from unilateral coronal synostosis from 2014.1 to 2017.1. All the patients had no abnormalities in nerve system, such as cephalomeningitis/ fistaul of cerebrospinal fluid/ epidural hematoma and so on.The distractor was not exposed. The width of extension ranged from 25—39 mm. One patient had infection in the rods around the distraction during the period of fixed, but was cured with antibiotic treatment and got an ideal extension eventually. The rest of 10 patients obtained the expected result . During a mean follow-up period of 12 months (5 to 26 months), all patients were presented with satisfactory cosmetic and functional result . CVAI were close to normal.@*Conclusions@#Treating unilateral coronal synostosis by internal distraction osteogenesis with supraorbital oblique osteotomy reduces the necessity offrontal and supraorbital osteotomy, and the exposure of the base of anterior cranial fossa, renders a safe and effective approach.
ABSTRACT
OBJECTIVE: Twist-drill craniostomy (TDC) with closed-system drainage and burr-hole drainage (BHD) with a closed system are effective treatment options for chronic subdural hematoma (CSDH). The aim of this study was to analyze clinical data and surgical results from symptomatic CSDH patients who underwent TDC with closed-system drainage at the pre-coronal point (PCP). METHODS: We analyzed data for 134 symptomatic CSDH patients who underwent TDC at the PCP with closed-system drainage. We defined the PCP for TDC to be 1 cm anterior to the coronal suture at the level of superior temporal line. TDC at the PCP with closed-system drainage was selected in patients with CSDH that extended beyond the coronal suture, confirmed by preoperative CT scans. Medical records, radiological findings, and clinical performance were reviewed retrospectively. RESULTS: Of the 134 CSDH patients, 114 (85.1%) showed improved clinical performance and imaging findings after surgery. Catheter failures were seen in two cases (1.4%); the catheters were inserted in the epidural space. Recurrent cases were seen in eight patients (5.6%), and they were improved with a second BHD with a closed-system operation. CONCLUSION: TDC at the PCP with closed-system drainage is safe and effective for patients with symptomatic CSDH whose hematomas extend beyond the coronal suture.
Subject(s)
Humans , Catheters , Drainage , Epidural Space , Hematoma , Hematoma, Subdural, Chronic , Medical Records , SuturesABSTRACT
The surgical treatment of the lesions located in the central lobe is a very difficult task for the neurosurgeon. The overall aim of this study is to verify the correlation of the coronal suture and the structures of the central lobe in 32 cadaver hemisphere brains and the importance of this information in surgical planning. The measurement of the nasion to the coronal suture ranged from 11.5 to 13.5 cm. The distance between the coronal suture in the midline to the central, precentral and paracentral sulcus ranged from 5.0 to 6.6, 2.5 to 4.5 and 1.3 to 4.0 cm respectively. Particularly in the normal cortex these measurements can be used to guide the surgical access. However, the identification of the central sulcus is not easy when the anatomical pattern is distorted or displaced by a lesion or edema. In cases such as these the use of other tools becomes crucial for good surgical planning and cortical mapping or awake craniotomy for a safer resection of the lesion as well.
O tratamento cirúrgico de lesões localizadas no lobo central é difícil para o neurocirurgião. O objetivo deste estudo é verificar a relação da sutura coronária com as estruturas do lobo central utilizando-se de dissecção realizada em 32 hemisférios cerebrais de 16 cadáveres, assim como, a importância desta informação no planejamento cirúrgico. A medida da distância entre o nasion e a sutura coronária variou entre 11,5 e 13,5 cm. A distância da sutura coronária na linha média para os sulcos central, pré-central e paracentral variou de 5,0 a 6,6 cm, 2,5 a 4,5 cm e 1,3 a 4,0 cm respectivamente. O conhecimento destas medidas pode ser usado no planejamento cirúrgico principalmente num córtex normal. Porém, a identificação do sulco central é difícil quando as estruturas anatômicas estão deslocadas pela lesão ou quando há edema. Nestes casos a utilização de outros meios diagnósticos para o planejamento cirúrgico torna-se necessária, como também a estimulação cortical ou a craniotomia com o paciente acordado pode proporcionar uma ressecção mais segura da lesão.