3.0 Tesla MRI scanner evaluation of supratentorial major white matter tracts and central core anatomical structures of postmortem human brain hemispheres fixed by Klingler method.

Background: As an advanced imaging technique for the human brain, the importance of magnetic resonance imaging technique (MRI) is indisputable. The study aims to contribute to the literature by imaging post-mortem human brain hemispheres fixed with the Klinger method through the a 3.0 Tesla MRI Scanner and by defining the supratentorial major white matter tracts and central core anatomical structures.Methods: In our study, 10 post-mortem human brain hemisphere specimens were placed in 10% formalin solution for at least two months according to the Klingler method. The images were obtained using a 3.0 Tesla MRI Scanner. Anatomical structures were described on the T1-T2 axial, coronal, and sagittal MRI sections and compared with control images obtained from healthy humans.Results: Our examination revealed major association fibers, the basal cores and nuclei were denser, and the connections between them were clearly visible. The basal nuclei particularly were visualized more clearly compared with the normal MRI examinations. The claustrum, putamen, lateral and medial part of globus pallidus, and the caudolenticular bridges of the caudate nucleus could be clearly distinguished. The optic radiation line toward the occipital area as well as the forceps major and minor were distinct in the axial sections. Meanwhile, the imaging emphasized the importance of temporal stem, and the fibers it contained were clearly observed in the coronal sections.Conclusion: The use of hemispheres fixed using the Klinger method in post-mortem MRI examinations on brain hemispheres showed a clear separation of white matter fibers and nuclear structures.

Comparison of Biomechanical Properties of Dura Mater Substitutes and Cranial Human Dura Mater : An In Vitro Study.

OBJECTIVE: The aim of this study was to investigate the biomechanical differences between human dura mater and dura mater substitutes to optimize biomimetic materials. METHODS: Four groups were investigated. Group I used cranial dura mater (n=10), group II used Gore-Tex® Expanded Cardiovascular Patch (W.L. Gore & Associates Inc., Flagstaff, AZ, USA) (n=6), group III used Durepair® (Medtronic Inc., Goleta, CA, USA) (n=6), and group IV used Tutopatch® (Tutogen Medical GmbH, Neunkirchen am Brand, Germany) (n=6). We used an axial compression machine to measure maximum tensile strength. RESULTS: The mean tensile strengths were 7.01±0.77 MPa for group I, 22.03±0.60 MPa for group II, 19.59±0.65 MPa for group III, and 3.51±0.63 MPa for group IV. The materials in groups II and III were stronger than those in group I. However, the materials in group IV were weaker than those in group I. CONCLUSION: An important dura mater graft property is biomechanical similarity to cranial human dura mater. This biomechanical study contributed to the future development of artificial dura mater substitutes with biomechanical properties similar to those of human dura mater.

Comparison of dural closure alternatives: an experimental study.

Introduction: Dural closure preference has been a topic of debate in contemporary neurosurgery. This study aims to compare different closure techniques using an in vitro model.Methods: Human cadaveric dura mater was attached to a cylindrical metal glass filled with blue dyed saline. A 1 cm dural incision was made. Dural closure was performed using three different techniques. Each group had six samples: Group I - interrupted simple 4-0 polyglactin suture (S) only, Group II - S plus on lay collagen graft, Group III - S plus fibrin sealant. In Group NS, a 1 cm × 1 cm dural window was made. An onlay collagen graft was used with no suturing for this group to serve as an overtly weak reconstruction reference. Primary and secondary leak pressures were recorded (PLP and SLP, respectively).Results: All groups (I-III) had significantly higher PLP and SLP than Group NS. PLP was significantly higher in Group III as compared to groups I and II. Groups I and II had similar PLP values. SLP was similar in all three groups.Conclusion: In this study, the use of fibrin sealant has proven to be the best option in preventing dural leak. However, no technique was superior in the case of SLP.

Biomechanical Properties of the Cranial Dura Mater with Puncture Defects : An In Vitro Study.

OBJECTIVE: The primary aim of this investigation was to explore the nature of dura mater biomechanics following the introduction of puncture defect(s). METHODS: Twenty-eight dura mater specimens were collected during autopsy from the department of forensic medicine of the authors' institution. Specimens were divided randomly into one of four groups : group I (cranial dura mater; n=7), group II (cranial dura mater with one puncture defect; n=7); group III (cranial dura mater with two puncture defects; n=7), and group IV (cranial dura mater with three puncture defects; n=7). RESULTS: The mean±standard deviation tensile strengths of the dura mater were 8.35±3.16, 8.22±3.32, 7.13±1.77, and 6.94±1.93 MPa for groups I, II, III, and IV, respectively. There was no statistical difference between all groups. A single, two or more punctures of the dura mater using a 20-gauge Quincke needle did not affect cranial dura tensile strength. CONCLUSION: This biomechanical study may contribute to the future development of artificial dura mater substitutes and medical needles that have a lower negative impact on the biomechanical properties of dura mater.