Table 2.

Modified Chang classification [3] evaluated from imaging and CSF patterns

	T1, n	T2, n	T3a, n	T3b, n	T4, n	Total, n (%)
M0, n	2	3	8	1	1	15 (50.0)
M1, n	0	0	0	0	0	0 (0)
M2, n	0	0	8	0	1	9 (30.0)
M3, n	0	0	1	0	0	1 (3.3)
M4, n	0	0	0	0	0	0 (0)
Total, n (%)	2 (6.7)	3 (10.0)	17 (56.7)	1 (3.3)	2 (6.6)	26 (86.7)*

Note. Condensed contrast-enhanced T1-w post Gd and T2-w imaging, lumbar puncture results, and additional staging were included. T stands for primary tumor, M for metastasis. T1 is tumor less than 3 cm in diameter and limited to midline, roof of the fourth ventricle, and cerebellar hemispheres. T2 is tumor more than 3 cm in diameter, invading one adjacent structure or partially filling the fourth ventricle. T4 is tumor spreading through the aqueduct of Sylvius, or tumor extending to the upper cervical cord. M0 stands for no evidence of metastasis. M1 is presence of microscopic tumor cells in CSF, M2 is gross nodular seeding demonstrated in the subarachnoid space or ventricles. M3 is gross nodular seeding in the spinal subarachnoid space; and M4 is extraneural metastasis. *Missing data due to lack of source imaging data.