From my (orthopedic) point of view, the most interesting in Biomedical Signal Processing will be semi-automatic analysis of SSEP and TES (or TMS) MEP in spine (scoliosis) surgery.
(good overview in http://blam-lab.org/wp-content/uploads/2015/01/bestmann.pdf)
There are plenty of scope as far as Biomedical signal processing is concerned. For example with regard to EMG many research are being done in the area of prostheses and muscle disorders. Similarly in the filed of EEG - brain based disorders like seizure, epilepsy, schizophrenia etc. Options are there in plenty.
I would also suggest you to visit some of the Universities in Europe to take a look at the current research being undertaken.