From the EU clinical trials register in Spanish and English

"E.3 Principal inclusion criteria... ≥1 new or enlarging T2 hyperintense lesion or gadolinium enhancing lesion* while on that same prior therapy (IFNB or GA)...≥1 lesión nueva o aumentada de tamaño hiperintensa en T2 o una lesión captante de gadolinio durante este mismo tratamiento previo (IFNB o AG)"

https://www.clinicaltrialsregister.eu/ctr-search/trial/2016-...
or contrast enhancing lesion.

From a paper on brain stem gliomas (abstract in Spanish and English)

"Mientras que la biopsia puede ser razonablemente evitada en las formas
difusas, es necesaria una prueba histológica en muchas lesiones del tallo cerebral cuando se evidencian lesiones captantes de contraste
debido a la gran variedad de diagnósticos diferenciales en los adultos...
While biopsy can be reasonably avoided in diffuse forms, a histological test is required in many brainstem lesions when contrast-enhancing lesions
are evident because of the wide variety of differential diagnoses in adults"
https://www.medigraphic.com/pdfs/revneuneupsi/nnp-2019/nnp19...

From a discussion on MRI lesions

"What are the differences between enhancing and nonenhancing lesions in MRI?...
In general, the terms 'enhancing' or 'non-enhancing' lesion refer to the uptake of Gadolinium-based contrast agent in the lesion...
In MRI field, usually the term "enhancing" is coupled with "gadolinium" or "contrast". Therefore, an enhancing lesion is a lesion that assumes contrast medium. In some cases this contrast-enhancing lesion may be acute (e.g. an acute multiple sclerosis lesion), but in other cases an enhancement may be even related to non-acute findings (e.g. vascular malformation)"
https://www.researchgate.net/post/What-are-the-differences-b...