diff --git a/CUDA/options/options.h b/CUDA/options/options.h
index 2f618e5cb63556039b08a57761448c5fb3379836..90a240e81d028033b43e91e1073c0e6aa8442738 100644
--- a/CUDA/options/options.h
+++ b/CUDA/options/options.h
@@ -1,5 +1,11 @@
-#define NDIRECTIONS 734 
-#define NFIBRES 3 
-#define NPARAMS 14
-#define MAXNDIRS_PER_THREAD 12
-#define THREADS_BLOCK 64
+#define MAXNFIBRES 4 
+#define MAXNPARAMS 15
+//NFIBRES*3 + S0 + d + d_std + f0 + rician = 15
+#define MAXNDIR 640
+//640 gradient directions
+#define THREADS_BLOCK_MCMC 64
+#define THREADS_BLOCK_FIT 64
+#define MAXNDIRS_PER_THREAD 10 
+//MAXNDIR/THREADS_BLOCK_MCMC
+
+