Table 1.
Intra-operative CSF leak grading system, reconstruction methods and reconstructive strategies.
Fig 1.
The “sandwich” multilayer closure.
Illustrations (A-F) depict a step-by-step multilayer closure after transtuberculum-transplanum approach for skull base tumors, such as meningioma or craniopharyngioma. A, shows a detail of the neurovascular structures that can be seen in this type of approach, when the tumor is removed; B, a first layer of derived dural is positioned “inlay”, with its edges under the dura; C, an autologous fat graft is collected at the abdomen and it is used to fill the dead spaces (it is considered intraosseous); D, a second layer of collagen derived matrix is positioned “onlay”, between the dura and bone edges, or over the bone defects; E, another layer of abdominal fat graft is positioned (extraosseous); F, finally NSF, harvested at the beginning of the surgery, is carefully rotated on the skull base defect, where the mucosa has already been removed to avoid mucocele formation.
Table 2.
Descriptive results.
Fig 2.
A, Post-operative CSF leak rate observed in different tumors, B, post-operative CSF leak analyzed in different type of surgical approach, according to different IOL groups; C, post-operative CSF leak analyzed in different IOL groups, D, post-operative CSF leak analyzed in different anatomical site, according to different IOL groups.
Table 3.
Post-operative CSF leak rate differentiated according to type of approach, site of approach and grade of intra-operative CSF leak.
Table 4.
Multivariate Logistic regression considering post-operative CSF leak rate (dependent variable) and type of approach, anatomical site of surgical approach, sex, intra-operative CSF leak grade, type of tumor and second surgery (independent variables), and univariate logistic regression for single grades of intra-operative CSF leak.
Table 5.
Post-operative CSF leak rate among different IHFL subgroups: Patients with type 3 reconstruction; use of different number of dural layers; use of fat and lumbar drain positioning.
Fig 3.
A population analysis over the years.
A graphical analysis of postoperative CSF-leak is represented in Graphs A and B; graphs C and D show the trend over time for no post-operative leak.
Fig 4.
A case example of "sandwich” multilayered reconstruction.
Preoperative sagittal (A) and coronal (B) MRI scans, show a T1w hypointense suprasellar 37x25 mm lesion with ring enhancement. C-G intra-operative views of reconstruction steps after a craniopharyngioma removal. C, Transtuberculum-transplanum approach for sopra-sellar pathology; note the optic chiasm pushed forward by the tumor; D, “inlay” synthetic dural substitute; E, "onlay” synthetic dural substitute, which is positioned over a first layer of autologous fat graft; F, pieces of autologous fat graft; G, NSF is fashioned over the layers previously described; three-months post-operative sagittal (H) and coronal (I) MRI scans (T1w with gadolinium), show GTR and the multiple layers adequately placed. No postoperative CSF-leaks was described in the current case.