What are the best options for resistant cases of ET?

Depends on what you mean by "resistant". Increasing doses of propranolol and primidone, as tolerated, is the simplest move. Other pharmacologic treatments like Topiramate and Gabapentin are sometimes tried but rarely effective. Simultaneous with this you'll want to refer the patient to OT for assistive devices such as weighted gloves, weighted utensils, and in some cases consider use of the CalaTrio device (downside being cost, and short time-course of improvement with each stim treatment). DBS should be considered next, and MR-guided focused ultrasound in patients who cannot undergo DBS. Both are highly effective, though DBS comes with fewer long-term side effects and a much better-studied safety profile over decades.

And above all, treatm...

I've had a couple of patients try this orthotic: readi-steadi.com.

Botox injection by a movement disorders specialist should also be considered for patients who want to avoid or delay DBS evaluation.

I used all above:

• Primidone
• Beta Blockers
• GBP
• TPX
• Clonazepam
• Botox 50-100 units in finger flexors and sometimes BR
• Weighted devices
• Focused US from Neuravive insightec.com. They have centers in NYU and Brigham and Women's Hospital in New England areas.

I also met a neurologist with ET and he also suggested Vitamin B2 and CoQ10 in the past.

I do not have much experience with DBS but that could be the last option.