Hi all,

 

I am having an topological defect error while running few of subjects. I have gone through the freesurfer correcting topological defects wikipage. But I was trying understand the log file. For an example, I got the following error for one subject:

 

Correction of the Topology

Finding true center and radius of Spherical Surface...done

Surface centered at (0,0,0) with radius 100.0 in 13 iterations

marking ambiguous vertices...

70557 ambiguous faces found in tessellation

segmenting defects...

78 defects found, arbitrating ambiguous regions...

analyzing neighboring defects...

      -merging segment 19 into 0

      -merging segment 22 into 0

      -merging segment 68 into 49

      -merging segment 61 into 55

74 defects to be corrected

0 vertices coincident

reading input surface /work/02510/sray2/Free_Sub/DATA/50011/50011/surf/lh.qsphere.nofix...

reading brain volume from brain...

reading wm segmentation from wm...

Computing Initial Surface Statistics

      -face       loglikelihood: -8.4264  (-4.2132)

      -vertex     loglikelihood: -5.7733  (-2.8866)

      -normal dot loglikelihood: -3.6047  (-3.6047)

      -quad curv  loglikelihood: -6.1117  (-3.0559)

      Total Loglikelihood : -23.9161

 

CORRECTING DEFECT 0 (vertices=27967, convex hull=5893)

Segmentation fault

 

mris_euler_number ../surf/lh.orig

 

mris_fix_topology failed! (euler number != 2)

Trying mris_topo_fixer...

 

cp ../surf/lh.orig.nofix ../surf/lh.orig

 

euler # = v-e+f = 2g-2: 116732 - 351516 + 234344 = -440 --> 221 holes

      F =2V-4:          234344 != 233464-4 (-884)

      2E=3F:            703032 = 703032 (0)

 

total defect index = 442

 

cp ../surf/lh.qsphere.nofix ../surf/lh.qsphere

 

 

cp ../surf/lh.smoothwm.nofix ../surf/lh.smoothwm

 

/work/02510/sray2/Free_Sub/DATA/50011/50011/scripts

 

mris_topo_fixer -mgz -warnings -seed 1234 50011 lh

 

verbose mode on (medium mode): printing warnings

setting seed for random number genererator to 1234

Before topology correction, eno=-440 (nv=116732, nf=234344, ne=351516, g=221)

Surface Diagnostics:      

   eno=-440 (nv=116732, nf=234344, ne=351516)

   # of border vertices [ #v ~ #f ]     0

   # of edges with single face          0

   # of edges with more than 2 faces    0

   # of corner configurations           0

   The original surface is a valid manifold

   Counting the number of connected components

   The original surface has one component

   The original surface does not self-intersect

 

The surface has 221 loops (X=-440)

 

Finding true center and radius of Spherical Surface...done

Surface centered at (0,0,0) with radius 100.0 in 9 iterations

identify defects...

marking ambiguous vertices...

68425 ambiguous faces found in tessellation

segmenting defects...

analyzing defects for overlaps...

INFO: assuming .mgz format

reading input surface /work/02510/sray2/Free_Sub/DATA/50011/50011/surf/lh.orig...

reading brain volume from brain...

reading wm segmentation from wm...

Detecting contrast direction: right direction [ GM (86.66) < WM (96.03) ]

Computing Initial Surface Statistics

      -face       loglikelihood: -5.8578  (-2.9289)

      -vertex     loglikelihood: -5.7524  (-2.8762)

      -normal dot loglikelihood: -3.6033  (-3.6033)

      -quad curv  loglikelihood: -5.8101  (-2.9050)

      Total Loglikelihood : -21.0236

 

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Correcting Topology of defect 1 with euler number -257 (129 loops)

   computing statistics for defect 1: 33364 vertices

   location: [ (156,125,84) - average intensity = 92.126 ]

      -gray ( 86.57 , 6.29 )  -white ( 95.91 , 6.08 )

      -gray ( 89.98 , 24.95 )  -white ( 98.58 , 24.03 )

      -intensity (86.574921 [log = -2.404119 ]- 95.914825 [log = -2.517448 ])

      -curv (k1=-0.162 (0.730) , r1 = 6.179 | k2=-0.060 (0.191), r2 = 16.806 )

      -curv (k1=-0.124 (0.768) , r1 = 8.076 | k2=-0.032 (0.282), r2 = 31.306 )

MRISalloc(8654176, 520): could not allocate vertices

Cannot allocate memory

 

 

And In some of my subjects the log file stop writing after: “CORRECTING DEFECT 0 (vertices=53786, convex hull=13985)”

 

My question is what exactly these highlighted number means? Do I have an estimation of number of slices that are to be treated manually?

 

Thanks,

-Siddharth