PDF(Pubmed)
Abstract：
BACKGROUND: Reimplantations of autologous skull flaps after decompressive hemicraniectomies (DHs) are associated with high rates of postoperative bone flap resorption (BFR). We histologically assessed the cell viability of explanted bone flaps in certain periods of time after DH, in order to conclude whether precursors of BRF may be developed during their storage.
METHODS: Skull bone flaps explanted during a DH between 2019 and 2020 were stored in a freezer at either -23 °C or -80 °C. After their thawing process, the skulls were collected. Parameters of bone metabolism, namely PTH1 and OPG, were analyzed via immunohistochemistry. H&E stain was used to assess the degree of avital bone tissue, whereas the repeated assays were performed after 6 months.
RESULTS: A total of 17 stored skull flaps (8 at -23 °C; 9 at -80 °C) were analyzed. The duration of cryopreservation varied between 2 and 17 months. A relevant degree of bone avitality was observed in all skull flaps, which significantly increased at the repeated evaluation after 6 months (p < 0.001). Preservation at -23 °C (p = 0.006) as well as longer storage times (p < 0.001) were identified as prognostic factors for higher rates of bone avitality in a linear mixed regression model.
CONCLUSIONS: Our novel finding shows a clear benefit from storage at -80° C, which should be carefully considered for the future management and storage of explanted skull flaps. Our analysis also further revealed a significant degree of bone avitality, a potential precursor of BFR, in skull flaps stored for several weeks. To this end, we should reconsider whether the reimplantation of autologous skull flaps instead of synthetic skull flaps is still justified.
METHODS: Skull bone flaps explanted during a DH between 2019 and 2020 were stored in a freezer at either -23 °C or -80 °C. After their thawing process, the skulls were collected. Parameters of bone metabolism, namely PTH1 and OPG, were analyzed via immunohistochemistry. H&E stain was used to assess the degree of avital bone tissue, whereas the repeated assays were performed after 6 months.
RESULTS: A total of 17 stored skull flaps (8 at -23 °C; 9 at -80 °C) were analyzed. The duration of cryopreservation varied between 2 and 17 months. A relevant degree of bone avitality was observed in all skull flaps, which significantly increased at the repeated evaluation after 6 months (p < 0.001). Preservation at -23 °C (p = 0.006) as well as longer storage times (p < 0.001) were identified as prognostic factors for higher rates of bone avitality in a linear mixed regression model.
CONCLUSIONS: Our novel finding shows a clear benefit from storage at -80° C, which should be carefully considered for the future management and storage of explanted skull flaps. Our analysis also further revealed a significant degree of bone avitality, a potential precursor of BFR, in skull flaps stored for several weeks. To this end, we should reconsider whether the reimplantation of autologous skull flaps instead of synthetic skull flaps is still justified.
摘要：
背景：去骨瓣切除术（DHs）后自体颅骨瓣的再植入与术后骨瓣吸收（BFR）的高速率相关。我们从组织学上评估了DH后某些时间段内外植骨瓣的细胞活力，以得出结论，在储存过程中是否可以开发BRF的前体。
方法：将在2019年至2020年的DH期间移植的颅骨皮瓣储存在-23°C或-80°C的冰箱中。在他们解冻后，头骨被收集起来了.骨代谢参数，即PTH1和OPG，通过免疫组织化学进行分析。H&E染色用于评估关节骨组织的程度，而重复检测是在6个月后进行的。
结果：分析了总共17个储存的颅骨皮瓣（-23°C下8个；-80°C下9个）。冷冻保存的持续时间在2到17个月之间变化。在所有颅骨皮瓣中观察到相关程度的骨活性，在6个月后重复评估时显着增加（p<0.001）。在线性混合回归模型中，在-23°C（p=0.006）下的保存以及更长的储存时间（p<0.001）被确定为较高骨活性率的预后因素。
结论：我们的新发现显示了在-80°C下储存的明显益处，应仔细考虑将来对移植的颅骨皮瓣的管理和存储。我们的分析还进一步揭示了骨骼的积极程度，BFR的潜在前体,在颅骨皮瓣中储存了几个星期。为此,我们应该重新考虑自体颅骨瓣而不是合成颅骨瓣的再植入是否仍然合理。
方法：将在2019年至2020年的DH期间移植的颅骨皮瓣储存在-23°C或-80°C的冰箱中。在他们解冻后，头骨被收集起来了.骨代谢参数，即PTH1和OPG，通过免疫组织化学进行分析。H&E染色用于评估关节骨组织的程度，而重复检测是在6个月后进行的。
结果：分析了总共17个储存的颅骨皮瓣（-23°C下8个；-80°C下9个）。冷冻保存的持续时间在2到17个月之间变化。在所有颅骨皮瓣中观察到相关程度的骨活性，在6个月后重复评估时显着增加（p<0.001）。在线性混合回归模型中，在-23°C（p=0.006）下的保存以及更长的储存时间（p<0.001）被确定为较高骨活性率的预后因素。
结论：我们的新发现显示了在-80°C下储存的明显益处，应仔细考虑将来对移植的颅骨皮瓣的管理和存储。我们的分析还进一步揭示了骨骼的积极程度，BFR的潜在前体,在颅骨皮瓣中储存了几个星期。为此,我们应该重新考虑自体颅骨瓣而不是合成颅骨瓣的再植入是否仍然合理。
