A method for detecting by spectroscopy an inhomogeneity (I) in a sample (E), includes that (i) the sample (E) is illuminated with incident light using means (23) for illuminating the sample (E), and (ii) the light re-emitted by the sample (E) is collected using means (24; 24′) for collecting the light, wherein (i) the light re-emitted by the sample (E) is collected at different spots arranged each spaced apart from the other spots and being located at the same distance from the means (23) for illuminating this sample (E) or their barycenter, and (ii) the presence of an inhomogeneity (I) in the sample (E) is determined based on the signals corresponding to the light re-emitted and collected at least at two different spots. A spectroscopic probe (2) and a device for analyzing a sample by spectroscopy implementing the method are also disclosed.