How was your horse diagnosed? 

Ultrasound 

My vet diagnosed my horse yesterday with a block. She said an ultrasound won’t show it because it’s encased in other things (muscles and...I don’t remember). She said an MRI would show exactly where and the severity, but I opted to just go ahead and start the long period of rest. 

A good, trusted friend told me last night that an ultrasound WOULD show it. So....I guess a second opinion is warranted?

A bet that knows how to u/s soft tissue can easily locate a suspensory problem (90%) the time. A lot of vets can ultrasound for repro but don't have the experience and/or equipment to diagnose soft tissue problems on legs. 

My vet xrayed first to rule out bone/joint, followed by ultrasound which showed enlarged suspensory.  I'd get second opinion for sure  

I think I would find a new vet

Thank you all - I will get a second opinion and let you know what they say! I appreciate your input. 

Mine was diagnosed with a block.

if a block was the only thing used to diagnose it was a guess, not a diagnosis