v3.26.1
Note 5 - Stockholders' Equity - Warrant Activity (Details) - Common Stock Warrants [Member] - $ / shares
 12 Months Ended
Apr. 30, 2026
Apr. 30, 2025
Jan. 31, 2026
Sep. 30, 2025
Apr. 30, 2024
Warrants, outstanding (in shares) 121,055 56,555      
Warrants, outstanding, exercise price (in dollars per share)     $ 5 $ 3.65  
Warrants, outstanding, weighted average strike price (in dollars per share) $ 9.59 $ 86.84     $ 182
Warrants, issued (in shares) 1,982,529 64,500      
Warrants, issued, weighted average strike price (in dollars per share) $ 4.97 $ 3.49      
Warrants, cancelled (in shares) (793)        
Warrants, forfeited (in shares) (244)        
Warrants, forfeited, weighted average strike price (in dollars per share) $ 0        
Warrants, outstanding (in shares) 2,102,547 121,055      
Minimum [Member]          
Warrants, outstanding, exercise price (in dollars per share) $ 0.001 $ 0.001     0.001
Warrants, issued, exercise price (in dollars per share) 3.65 3.35      
Maximum [Member]          
Warrants, outstanding, exercise price (in dollars per share) 425 825     $ 825
Warrants, issued, exercise price (in dollars per share) $ 5 $ 5.15