Table 3. Structural MR imaging findings in diffuse midline glioma, H3 K27M histone-mutant in this case series.

Case	Age	Tumour location	T2 volume cm3	T2/FLAIR margin	T2/FLAIR signal	Haem	Ca2	Cyst(s)	T1w+Gad pattern	Hydrocephalus
1	17	Thalamus, lentiform	39.2	Distinct	Het	Macro	No	No	Solid, rim enhancing + necrosis	Shunt
2	14	Cerebellum, pons, leptomeninges	33.1	Indistinct	Het	Ukn	Ukn	No	Solid, rim enhancing + necrosis	Shunt
3	17	Pons	38.9	Indistinct	Het	No	No	Yes	Rim enhancing + necrosis	No
4	19	Thalamus, corona radiata midbrain	103.1	Distinct	Het	Macro	No	No	Rim enhancing + necrosis	Shunt
5	30	Thalamus, temporal	85	Indistinct	Het	Macro	No	No	Rim enhancing + necrosis	Mild
6	64	Basal ganglia septum pellucidum, bifrontal	48.4	Indistinct	Het	No	No	No	Non-enhancing	No
7	50	Midbrain, pons	13.9, then 19.4	Distinct	Hom	No	No	No	Non-enhancing*	No
8	15	Thalamus, midbrain	66.85	Distinct	Het	No	No	No	Rim enhancing + necrosis	Mild
9	33	Thalami, tectal plate	11.4	Distinct	Hom	No	No	No	Non-enhancing	Shunt
10	16	Thalami, midbrain	57.1	Indistinct	Het	Petechial	No	No	Solid, rim enhancing + necrosis	Shunt
11	14	Medulla	9.2	Distinct	Het	Ukn	Ukn	No	No Gad given	No
12	17	Tectal plate	13.5	Distinct	Het	No	No	No	Solid, rim enhancing + necrosis	Mild
13	60	Pons	43.4	Indistinct	Het	No	No	No	Solid	No
14	35	Thalamus	54.7	Distinct	Het	No	No	Yes	Rim enhancing + necrosis	Shunt
15	44	Hypothalamus, pituitary, caudate, temporal lobe	24.1	Indistinct	Het	Petechial	No	No	Rim enhancing + necrosis	No

*, in case 7 gadolinium enhancement developed subsequently. Haem, haemorrhage; Macro, macroscopic; Ca²⁺, calcification; Hom, homogenous; Het, heterogeneous; Ukn, unknown.