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Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Apr. 30, 2025 | Apr. 30, 2024
--- | --- | ---
Income Tax Disclosure [Abstract] |  |
Federal net operating loss carryforwards | $ 52,496 | $ 48,745
Foreign net operating loss carryforwards |  | 2,059
State operating loss carryforwards | 1,950 | 1,934
Federal and New Jersey research and development tax credits | 5,553 | 5,404
Stock compensation | 378 | 470
Accrued expenses | 188 | 312
Research and experimentation expenses | 2,259 | 1,977
Other | 337 | 601
Net deferred tax assets before valuation allowance | 63,161 | 61,502
Valuation allowance | (62,192) | (60,322)
Deferred tax assets | 969 | 1,180
Intangibles | (788) | (793)
Lease liabilities | (384) | (590)
Net deferred tax liabilities | $ (203) | $ (203)

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