The use of nuclear resonances techniques for characterizing the distribution and lattice location of implanted atoms in metals is a direct and, in principle, simple method for studying helium and hydrogen gas in CTR first wall materials. However, the reaction 3He(d,p) 4He, has a broad (350 keV) half-width in the resonance yield curve. When using a deuteron beam, under normal probing conditions, to measure helium distributions in metals, a rather low stopping power results in limited resolution of about 3 μm. In many cases resolution of a few thousand angstroms or better is necessary. We have experimentally examined two resolution enhancement methods and reported the results in a previous article. The present paper will review those results and examine limitations of resolution enhancement that are obtainable through geometrical and mathematical techniques.