TABLE 5.

The effect of covariates on HARDI tractography measurements in PHTS and NC; Univariate General Linear Model

Measurement	PHTS (N = 9) mean [SD]	NC (N = 9) mean [SD]	The rate of PHTS/NC	R squired	Corrected model	The presence of PHTS	Age	Gender
Volume (ml)
AF, left	21.2 [13.5]	11.8 [6.4]	1.8	0.641	F = 4.92 p = 0.016	F = 14.2 p = 3.1 × 10−3	F < 1.0 × 10−4 p = 0.99	F = 3.58 p = 0.085
AF, right	19.1 [9.7]	11.5 [6.2]	1.7	0.602	F = 4.16 p = 0.027	F = 12.7 p = 4.5 × 10−3	F = 0.011 p = 0.92	F = 3.41 p = 0.092
ILF, left	18 [7.5]	9.5 [2.8]	1.9	0.667	F = 5.51 p = 0.011	F = 21.0 p = 7.8 × 10−4	F = 0.85 p = 0.38	F = 1.44 p = 0.26
ILF, right	13.6 [7.2]	9.0 [2.4]	1.5	0.409	F = 1.90 p = 0.18	F = 3.19 p = 0.10	F = 0.34 p = 0.57	F = 0.34 p = 0.57
IFOF, left	9.7 [7.9]	15.1 [3.8]	0.6	0.271	F = 1.02 p = 0.44	F = 1.7 p = 0.22	F = 0.14 p = 0.71	F = 0.79 p = 0.39
IFOF, right	12 [5.7]	17.0 [5.8]	0.7	0.184	F = 0.62 p = 0.66	F = 0.79 p = 0.39	F = 1.28 p = 0.28	F = 0.14 p = 0.71
UF, left	5 [3.4]	7.8 [2.2]	0.6	0.620	F = 4.49 p = 0.022	F = 0.70 p = 0.42	F = 3.19 p = 0.10	F = 3.76 p = 0.079
UF, right	7.2 [3.7]	7.5 [2.1]	1.0	0.539	F = 3.22 p = 0.056	F = 1.65 p = 0.23	F = 0.78 p = 0.40	F = 3.35 p = 0.094
CF, left	10.7 [5.2]	7.1 [2.1]	1.5	0.730	F = 7.43 p = 3.8 × 10−3	F = 2.95 p = 0.11	F = 1.21 p = 0.29	F = 6.91 p = 0.023
CF, right	9.5 [5.4]	6.3 [1.4]	1.5	0.593	F = 4.01 p = 0.03	F = 4.50 p = 0.057	F = 2.68 p = 0.13	F = 0.54 p = 0.48
FF, left	3.7 [2.1]	6.5 [1.9]	0.6	0.379	F = 1.68 p = 0.22	F = 2.50 p = 0.14	F = 0.14 p = 0.72	F = 0.001 p = 0.98
FF, right	4.3 [2.6]	6.8 [2.1]	0.6	0.297	F = 1.16 p = 0.38	F = 1.51 p = 0.24	F = 0.13 p = 0.72	F = 0.084 p = 0.78
CP	161.6 [31.2]	101.7 [23.9]	1.6	0.796	F = 10.7 p = 8.7 × 10−4	F = 38.9 p = 6.4 × 10−5	F = 4.26 p = 0.063	F = 4.28 p = 0.063
Lengths (mm)
AF, left	57.4 [20.6]	49.2 [17.2]	1.2	0.500	F = 2.76 p = 0.082	F = 0.90 p = 0.36	F = 3.76 p = 0.079	F = 0.58 p = 0.46
AF, right	47.5 [13.7]	46.1 [15.4]	1.0	0.226	F = 0.80 p = 0.55	F = 0.082 p = 0.78	F = 0.24 p = 0.63	F = 0.41 p = 0.54
ILF, left	81.7 [13.8]	48.6 [7.5]	1.7	0.777	F = 9.58 p = 1.4 × 10−3	F = 36.7 p = 8.2 × 10−5	F = 0.42 p = 0.53	F = 0.83 p = 0.38
ILF, right	74.5 [18.0]	43.5 [4.6]	1.7	0.884	F = 21.0 p = 4.1 × 10−5	F = 62.9 p = 7.1 × 10−6	F = 0.78 p = 0.40	F = 2.71 p = 0.13
IFOF, left	135.4 [19.7]	63.6 [12.5]	2.1	0.857	F = 16.5 p = 1.3 × 10−4	F = 51.7 p = 1.8 × 10−5	F = 0.041 p = 0.84	F = 1.58 p = 0.24
IFOF, right	132.5 [18.0]	66.3 [12.5]	2.0	0.891	F = 22.6 p = 3.0 × 10−5	F = 89.6 p = 1.3 × 10−6	F = 0.031 p = 0.86	F = 1.61 p = 0.23
UF, left	66.4 [19.5]	34.4 [5.9]	1.9	0.707	F = 6.65 p = 5.7 × 10−3	F = 20.0 p = 9.5 × 10−4	F = 1.01 p = 0.34	F = 2.24 p = 0.16
UF, right	89.2 [16.2]	40.1 [8.6]	2.2	0.917	F = 30.6 p = 6.6 × 10−6	F = 107.9 p = 5.1 × 10−7	F = 6.2 × 10−3 p = 0.94	F = 0.30 p = 0.60
CF, left	58.3 [28.4]	39.6 [8.2]	1.5	0.482	F = 2.56 p = 0.098	F = 8.54 p = 0.014	F = 0.88 p = 0.37	F = 0.42 p = 0.53
CF, right	52.9 [24.8]	38.5 [11.9]	1.4	0.392	F = 1.77 p = 0.20	F = 2.67 p = 0.13	F = 0.023 p = 0.88	F = 2.20 p = 0.17
FF, left	54.2 [24.1]	44.5 [18.2]	1.2	0.124	F = 0.39 p = 0.81	F = 1.41 p = 0.26	F = 0.03 p = 0.87	F = 0.084 p = 0.78
FF right	53.5 [21.0]	42.0 [13.3]	1.3	0.397	F = 1.81 p = 0.20	F = 4.32 p = 0.062	F = 0.97 p = 0.35	F = 0.59 p = 0.46
CP	90.4 [7.8]	70.0 [10.6]	1.3	0.681	F = 5.87 p = 8.9 × 10−3	F = 22.5 p = 6.1 × 10−4	F = 0.48 p = 0.50	F = 0.43 p = 0.52
FA
AF, left	0.42 [0.06]	0.47 [0.05]	0.9	0.698	F = 6.36 p = 6.7 × 10−3	F = 8.62 p = 0.014	F = 13.8 p = 3.4 × 10−3	F = 0.18 p = 0.68
AF, right	0.41 [0.06]	0.47 [0.03]	0.9	0.588	F = 3.92 p = 0.032	F = 10.7 p = 7.5 × 10−3	F = 2.6 p = 0.13	F = 0.57 p = 0.46
ILF, left	0.45 [0.05]	0.52 [0.02]	0.9	0.850	F = 15.6 p = 1.7 × 10−4	F = 40.3 p = 5.5 × 10−5	F = 17.5 p = 0.0015	F = 0.051 p = 0.82
ILF, right	0.43 [0.08]	0.52 [0.02]	0.8	0.689	F = 6.10 p = 7.7 × 10−3	F = 16.3 p = 2.0 × 10−3	F = 5.34 p = 0.041	F = 0.44 p = 0.52
IFOF, left	0.50 [0.05]	0.54 [0.03]	0.9	0.711	F = 6.76 p = 5.3 × 10−3	F = 10.0 p = 8.9 × 10−3	F = 13.1 p = 0.004	F = 0.005 p = 0.94
IFOF, right	0.48 [0.04]	0.52 [0.03]	0.9	0.715	F = 6.91 p = 4.9 × 10−3	F = 12.3 p = 5.0 × 10−3	F = 10.2 p = 8.4 × 10−3	F = 0.27 p = 0.62
UF, left	0.41 [0.06]	0.42 [0.02]	1.0	0.342	F = 1.43 p = 0.29	F = 1.07 p = 0.32	F = 0.47 p = 0.51	F = 1.75 p = 0.21
UF, right	0.43 [0.05]	0.43 [0.02]	1.0	0.502	F = 2.77 p = 0.081	F = 0.12 p = 0.74	F = 3.92 p = 0.073	F = 0.63 p = 0.44
CF, left	0.46 [0.06]	0.49 [0.04]	0.9	0.439	F = 2.15 p = 0.14	F = 1.12 p = 0.31	F = 1.42 p = 0.26	F = 2.26 p = 0.16
CF, right	0.46 [0.07]	0.46 [0.04]	1.0	0.649	F = 5.1 p = 0.014	F = 0.082 p = 0.78	F = 8.34 p = 0.015	F = 1.31 p = 0.28
FF, left	0.40 [0.08]	0.42 [0.04]	1.0	0.106	F = 0.33 p = 0.85	F = 0.12 p = 0.74	F = 0.04 p = 0.85	F = 0.30 p = 0.59
FF, right	0.37 [0.06]	0.40 [0.04]	0.9	0.188	F = 0.64 p = 0.65	F = 0.55 p = 0.47	F = 0.16 p = 0.7	F = 1.30 p = 0.28
CP	0.55 [0.04]	0.59 [0.03]	0.9	0.520	F = 2.98 p = 0.068	F = 8.91 p = 0.012	F = 1.3 p = 0.28	F = 0.13 p = 0.73
ADC (mm2/s × 10−5)
AF, left	89.7 [8.1]	81.2 [3.7]	1.1	0.720	F = 7.06 p = 4.5 × 10−3	F = 13.1 p = 4.0 × 10−3	F = 14.0 p = 3.2 × 10−3	F = 1.04 p = 0.33
AF, right	89.5 [7.8]	81.5 [4.0]	1.1	0.708	F = 6.68 p = 5.6 × 10−3	F = 14.2 p = 3.1 × 10−3	F = 9.02 p = 0.012	F = 0.17 p = 0.69
ILF, left	97.9 [5.6]	88.8 [3.7]	1.1	0.706	F = 6.59 p = 5.9 × 10−3	F = 19.5 p = 0.001	F = 6.32 p = 0.029	F = 0.19 p = 0.67
ILF, right	97.6 [10.8]	90.5 [2.4]	1.1	0.477	F = 2.51 p = 0.10	F = 2.51 p = 0.14	F = 7.15 p = 0.022	F = 1.11 p = 0.31
IFOF, left	93.2 [5.6]	85.3 [3.7]	1.1	0.750	F = 8.25 p = 2.5 × 10−3	F = 27.8 p = 2.6 × 10−4	F = 3.29 p = 0.097	F = 0.65 p = 0.44
IFOF, right	90.7 [8.4]	86.5 [3.5]	1.1	0.388	F = 1.75 p = 0.21	F = 2.67 p = 0.13	F = 3.98 p = 0.07	F = 0.20 p = 0.66
UF, left	92.2 [6.5]	87.8 [3.1]	1.1	0.440	F = 2.16 p = 0.14	F = 5.41 p = 0.04	F = 2.07 p = 0.18	F = 0.20 p = 0.66
UF, right	89.3 [5.8]	88.1 [2.6]	1.0	0.475	F = 2.49 p = 0.10	F = 0.70 p = 0.42	F = 6.51 p = 0.027	F < 1.0 × 10−4 p = 1.0
CF, left	91.6 [10.8]	84.7 [3.4]	1.1	0.228	F = 0.81 p = 0.54	F = 2.35 p = 0.15	F = 0.53 p = 0.48	F = 7.2 × 10−3 p = 0.93
CF, right	88.2 [8.4]	85.2 [2.8]	1.0	0.539	F = 3.22 p = 0.056	F = 2.90 p = 0.12	F = 5.4 p = 0.04	F = 0.34 p = 0.57
FF, left	119.7 [23.6]	120.8 [13.5]	1.0	0.090	F = 0.27 p = 0.89	F = 0.12 p = 0.74	F = 0.26 p = 0.62	F = 0.62 p = 0.45
FF, right	123.8 [18.1]	127.6 [14.9]	1.0	0.179	F = 0.60 p = 0.67	F = 0.095 p = 0.76	F = 0.29 p = 0.6	F = 0.016 p = 0.90
CP	91.2 [6.6]	88.0 [3.6]	1.0	0.537	F = 3.19 p = 0.057	F = 5.88 p = 0.034	F = 3.53 p = 0.087	F = 0.043 p = 0.84

Abbreviations: ADC, apparent diffusion coefficient; AF, arcuate fasciculus; CF, cingulum fasciculus; CP, callosal pathway; DTI, Diffusion tensor imaging; FA, fractional anisotropy; FF, fornix fasciculus; IFOF, inferior fronto-occipital fasciculus; ILF, inferior longitudinal fasciculus; NC, Neurotypical controls; PHTS, PTEN hamartoma tumor syndrome; SD, Standard deviation; UF, uncinate fasciculus.

Bold entries indicate a measurement exhibiting statistically significant group-wise differences. A General Linear Model (p < 0.05) was constructed to evaluate the effects of continuous or binary covariates (age and gender). Critical values from the F-distribution calculation were determined to be F(0.05,4,13) = 3.18 and F(0.05,1,13) = 4.67, for the corrected model and each covariate, respectively.