| Objective:To appreciate the anatomical characteristics of the occipital muscles,blood vessels,nerves,and the posteroinferior point of the transverse sigmoid sinus junction(PSTS),and then modify the traditional suboccipital retrosigmoid approach based on the appreciations of the aforementioned anatomical structures,thereby providing a solid anatomical basis for modifying traditional suboccipital retrosigmoid approach.Methods:First of all,the distance between the most commonly used burr hole asterion and PSTS(Ast-PSTS),and the distance between our new burr hole point O and PSTS(OPSTS)were measured on 62 dry adult skulls(the left skulls: 35;the right skulls: 27),and then the measured data were statistically analyzed.Then the occipital regions were elaborately microdissected on 7(14 sides)adult cadaveric head specimens with neck fixed by 10% formalin,and all the relevant measurements were accurately performed and analyzed during the microdissections.Finally,the modified retrosigmoid approach with "sickle incision" and point O as the burr hole location were verified on these specimens,while the degrees of the tissue damage to the occipital nerves,blood vessels,and muscles were recorded in the course of microdissection.Results:The modified retrosigmoid approach with "sickle incision" significantly reduced the degrees of the tissue damage to the occipital nerves,blood vessels,and muscles.Compared with dispersion and variability of Ast-PSTS distance data,the dispersion and variability of O-PSTS distance data were significantly smaller(P<0.05).Conclusion:All the anatomical structures of the occiputs and their relationships are well appreciated.Our unprecedented "sickle incision" can significantly reduce the degrees of damage to the occipital blood vessels,nerves and muscles;in addition,our unconventional point "O" as a burr hole location is more accurate and reliable than the conventional asterion point. |
