Table 1.

Biophysical properties of the spinal dura mater.

Author	Year	Property	Method of measurement	Results	Comments
Sin and Coburn [20]	1983	Electrical resistivity (phenomenological)	Computational modeling	ρe = 20 Ωm = σ.1/ρe = 0.05 S/m	Same value as that specified for epicardial fat
Groen et al. [6]	1988	Innervation	Anatomical study	Dorsal dura is much less innervated compared to ventral dura	Dorsal nerves derived from the ventral dural plexus
Patin et al. [14]	1993	Tensile strength	Instron biomechanical testing	Maximum was Ts = 98 N for samples 1.5 cm long by 1.0 cm wide	Longitudinal tensile strength 5 to 11 times greater the that of the transverse direction
Vandenabeele et al. [9]	1996	Microscopic structure	Transmission electron microscopy	Outermost portion with a thickness of 2 μm, with a low density of collagen Middle and thicker portion was richly vascularized and abundant in extracellular collagen intermingled Inner layer, in intimate contact with the parietal arachnoid, presented dark cells ~8 mm thick, with interdigitated cell extensions, enlarged extracellular space	Helically distributed extracelluar collagen
Schenck [26]	1996	Magnetic susceptibility	Standard value accepted for soft tissues	χ ≈ −9 × 10−6	Taken to be that of water at body temperature
Runza et al. [8]	1999	Microscopic structure, tensile strength, stiffness	Scanning electron microscopy and monoxial tensile tests	Close correlation between the microstructural anatomy and biomechanical properties of lumbar dura mater	Stronger tensile strength and stiffness in the longitudinal direction
Oates [25]	2000	Electrical resistivity (measured)	Impedance determined from voltage produced across a sample of dura mater through which constant amplitude currents were driven	Average resistivity: ρe = (67.4 ± 26.6) Ωcm	Frequency range: 10 Hz to 5 kHz
Genina et al. [29]	2005	Optical characteristics	Diffusion of aqueous mannitol to produce matching of indices of refraction	n =1.474 (dural collagen fibrils) and n = 1.345 (dural interstitial fluid) at λ 589 nm	The manitol infusion produced “optical clearing” of the membrane
Chauvet et al. [7]	2009	Thickness	Optical microscopy/digital micrometer gauge	Mean: d = (1.106 ± 0.244) mm	Craniocervical junction specimens
Watanabe et al. [32]	2009	MR imaging characteristics	Spinal MR imaging	Hypointense thin layer in T1and T2-weighted MRI	The T2-weighted images provide better visualization because of the higher contrast achieved relative to the surrounding structures
McIntosh and Anderson [19]	2010	Thermal characteristics	Literature review	Heat capacity: s = 3364 J kg−1 °C−1 Thermal conductivity: k = 0.44 W m−1 °C−1 Water content = 68% Density: ρ = 1174 kg m−3 Blood flow rate = 38 ml min−1 100 g−1 Perfusive cooling strength = 28390 W m−3 °C−1 Metabolic heat production = 4144 W m−3	Based in literature review the authors developed a database of thermal properties for 43 human tissues