PURPOSE: Recognizing spinal cord dose limits in various fractionations is essential to ensure adequate dose for @entity5 control while minimizing the chance of @entity15698 ( @entity15698 ). This study aimed to determine the a/b ratio of the spinal cord and the cord dose limit in terms of BED50, the biological equivalent dose (BED) that induces 50  % chance of @entity15698 , by fitting data collected from published animal and @entity1 studies. METHODS: @entity15698 data from five @entity35 studies; three large animal studies on monkeys, @entity235 , and @entity1707 ; and 18 @entity1 studies were included for the investigation. The a/b ratios were derived, respectively, for @entity35 (group A), large animal (group B), @entity1 (group C), and combined data (group D). RESULTS: The a/b ratio (and its 95 % confidental interval)  was 4.1 (3.2, 5.0) or 3.6 (2.6, 4.6) Gy for group A, depending on fitting algorithms. It was 3.9 (3.0, 4.8), 3.7 (2.2, 8.2) and 3.9 (3.0, 4.9) for groups B, C, and D, respectively. BED50 was 111  Gy for the combined data. It corresponds to a D50 of 73.4  Gy in 2  Gy/FX, or 19.0  Gy in single fraction. BED5, which is the BED to induce 5  % of @entity15698 , was calculated to be 83.9  Gy. It corresponds to D5 of 55.4  Gy in 2  Gy/FX, or 16.2  Gy in single fraction. CONCLUSION: The study showed that all four groups had similar a/b ratios close to 3.9  Gy, suggesting that the spinal cord has a similar fractionation effect for different species, including @entity1 beings.

Radiation dose-fractionation effects in spinal cord: comparison of animal and XXXX data.

@entity1 :: ('9606', 'Species') :: ['human', 'patient'] @entity1707 :: ('9823', 'Species') :: ['pigs'] @entity15698 :: ('MESH:D009381', 'Disease') :: ['RIM', 'radiation-induced myelopathy'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor'] @entity235 :: ('9615', 'Species') :: ['dogs'] @entity35 :: ('10116', 'Species') :: ['rat']
@entity1 :: (9606,Species) :: ['human']
