OBJECTIVE: To clarify whether it is necessary to reconstruct bone defects at the anterior skull base. METHODS: A long-term follow-up study of 50 patients with anterior skull-base defects in which the dura was reconstr...OBJECTIVE: To clarify whether it is necessary to reconstruct bone defects at the anterior skull base. METHODS: A long-term follow-up study of 50 patients with anterior skull-base defects in which the dura was reconstructed without bone grafts was conducted. CT and MRI examinations were taken periodically after surgery. RESULTS: The ordinates of the bone defects averaged 3.5 cm (range, 2 - 6 cm), and the abscissas averaged 2.8 cm (range, 2 - 5 cm). The abscissas of the bone defects measured 2 - 3 cm in 38 patients, 3 - 4 cm in 10 patients, and 4 - 5 cm in 2 patients. The follow-up ranged from 3 months to 5 years (average, 2 years). CONCLUSIONS: At normal intracranial pressure, if the dura mater is repaired properly at the skull-base defects and reinforced with a pedicled pericranial flap, encephalomeningocele and cerebrospinal fluid (CSF) leakage can be prevented. It may not be necessary to make free bone grafts when the size of the cranial base bone defect is smaller than 4 cm.展开更多
OBJECTIVE: To investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects. METHODS: A measu...OBJECTIVE: To investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects. METHODS: A measurement of creep properties of human dura and its substitutes were conducted using biomechanical tests. The dynamic changes of biomechanical properties of canine dura obtained from skull base defects were observed as well. RESULTS: The creep properties of human dura presented a linear-relationship between initial strain and stress, and the creep strain increased slowly with time. The creep compliance formula for human dura and its substitutes was as follows: J (t) = J(0) + Kf (t). The initial compliance of canine dura in skull base defects was reduced by 35%, 46% and 50%, respectively 1, 3 and 6 months after surgery. CONCLUSION: The optimal material for the repair of skull base defects can be estimated using creep compliance analysis. The less the compliance, the better the property of anti-protrusion. Fresh human dura is the least compliant and then in increasing order are lyophilized human dura, fresh human pericranium, Terylene and silicon membranes. The pattern of biomechanical characteristics of the dura mater at skull base defects shows that the strain ability of the dura mater decreases distinctly for 1 - 3 months and then remains almost unchanged for 3 - 6 months after surgery.展开更多
文摘OBJECTIVE: To clarify whether it is necessary to reconstruct bone defects at the anterior skull base. METHODS: A long-term follow-up study of 50 patients with anterior skull-base defects in which the dura was reconstructed without bone grafts was conducted. CT and MRI examinations were taken periodically after surgery. RESULTS: The ordinates of the bone defects averaged 3.5 cm (range, 2 - 6 cm), and the abscissas averaged 2.8 cm (range, 2 - 5 cm). The abscissas of the bone defects measured 2 - 3 cm in 38 patients, 3 - 4 cm in 10 patients, and 4 - 5 cm in 2 patients. The follow-up ranged from 3 months to 5 years (average, 2 years). CONCLUSIONS: At normal intracranial pressure, if the dura mater is repaired properly at the skull-base defects and reinforced with a pedicled pericranial flap, encephalomeningocele and cerebrospinal fluid (CSF) leakage can be prevented. It may not be necessary to make free bone grafts when the size of the cranial base bone defect is smaller than 4 cm.
基金ThisstudywassupportedbyagrantfromtheNationalNaturalScienceFoundationofChina (No 3 9670 199)
文摘OBJECTIVE: To investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects. METHODS: A measurement of creep properties of human dura and its substitutes were conducted using biomechanical tests. The dynamic changes of biomechanical properties of canine dura obtained from skull base defects were observed as well. RESULTS: The creep properties of human dura presented a linear-relationship between initial strain and stress, and the creep strain increased slowly with time. The creep compliance formula for human dura and its substitutes was as follows: J (t) = J(0) + Kf (t). The initial compliance of canine dura in skull base defects was reduced by 35%, 46% and 50%, respectively 1, 3 and 6 months after surgery. CONCLUSION: The optimal material for the repair of skull base defects can be estimated using creep compliance analysis. The less the compliance, the better the property of anti-protrusion. Fresh human dura is the least compliant and then in increasing order are lyophilized human dura, fresh human pericranium, Terylene and silicon membranes. The pattern of biomechanical characteristics of the dura mater at skull base defects shows that the strain ability of the dura mater decreases distinctly for 1 - 3 months and then remains almost unchanged for 3 - 6 months after surgery.
