Article Figures & Data
Figures
- FIG 1.
Predesigned radiologic flow chart created according to the literature before diagnostic accuracy analysis. The asterisk indicates brain stem tumors excluded from the analysis. Double asterisks indicate relative to gray matter. Modified with permission from D'Arco et al.11
- FIG 2.
Diagnostic accuracy of a predesigned radiologic flow chart to identify different types of cerebellar tumors.
- FIG 3.
Diagnostic accuracy of sequence 312 (all types of medulloblastomas) of the predesigned radiologic flow chart to identify different types of medulloblastomas.
- FIG 4.
Modified radiologic flow chart (flow chart 2) after diagnostic accuracy analysis. The asterisk indicates brain stem tumors excluded from the analysis. Double asterisks indicate relative to gray matter. Triple asterisks indicates low PPV and sensitivity for any particular molecular/histological group of tumor.
- FIG 5.
Differential diagnoses in cases of posterior fossa tumors originating from the cerebellar hemisphere. Axial T2WI (A) and axial ADC map (B) show SHH medulloblastoma (flow chart 2, number 111) in a typical peripheral location within the cerebellar hemisphere due to its origin from ganglionic cell precursors. Note very low ADC values (ie, diffusion restriction). Axial T2WI (C) and axial ADC map (D) show the typical appearance of a pilocytic astrocytoma (flow chart 2, number 123) originating from the cerebellar hemisphere. Note the typical nodule and appearance of cysts and much higher ADC values in comparison with the medulloblastoma.
- FIG 6.
Differential diagnoses in posterior fossa tumors involving the foramen of Luschka and cerebellopontine angle. Axial T2WI (A) and ADC map (B) in a child with ependymoma (flow chart 2, number 423). Note the presence of internal vessels (arrow) and intermediate ADC values. Axial T2 (C) and ADC maps (D) in a 2-year-old boy with a AT/RT (new flow chart number 411). Note very low values of ADC, suggesting an embryonal tumor and peripheral cysts.
Tables
- Table 1:
Statistical analysis of the radiologic flow chart to discriminate different types of cerebellar tumors
Diagnosis Equivalent Flowchart Sequence Sensitivity (%) Specificity (%) PPV (%) NPV (%) Accuracy (%) Ependymoma 323/423 89 (67–99) 95 (89–98) 71 (49–87) 98 (94–100) 94 (89–97) Pilocytic astrocytoma 123 88 (76–95) 96 (89–99) 92 (82–98) 93 (85–97) 93 (87–96) AT/RT 411 50 (21–79) 99 (96–100) 86 (42–100) 96 (91–98) 99 (96–100) AT/RT 411/311 75 (43–95) 98 (94–100) 75 (43–95) 98 (94–100) 91 (96–98) Medulloblastoma SHH 111/112/313 71 (42–92) 93 (88–97) 53 (29–76) 97 (92–99) 72 (64–79) Medulloblastoma WNT 412 14 (0–58) 97 (93–99) 20 (1–72) 96 (91–98) 88 (93–97) - Table 2:
Likelihood ratio analysis of the radiologic flow chart to discriminate different types of cerebellar tumors
Diagnosis Flow Chart Sequence LR+ (95% CI) LR– (95% CI) AT/RT 411/311 34 (10.6–109)a 0.26 (0.1–0.7) Ependymoma 323/423 16.5 (7.9–35) 0.11 (0.03–0.4)a Medulloblastoma SHH 111/112/313 10.6 (5.2–21.7) 0.3 (0.1–0.7) Medulloblastoma group 3 or 4 312 10.07 (5.3–19.3) 0.23 (0.12–0.45)a Pilocytic astrocytoma 123 20 (7.7–52.8) 0.13 (0.13–0.26)a ↵a Clinically applicable confidence intervals.
