Shares in Surgical Innovation tumbled after it warned that following a recent review its full year revenues would be around £0.6m lower than previously anticipated.The instrument maker explained that the review, which was launched in late September, had identified revenues that had previously been recognised on some of its transactions where a sales return will be required.The company will also face further exceptional charges of around £1.6m thanks to redundancy payouts and one-off costs.Anticipated losses for the full year continue to be "significant", the group cautioned."Against this backdrop, short-term working capital funding and cash generation remains the board's key priority and further updates will be provided to shareholders as appropriate," it said.The share price had fallen 32.63% to 1.60p by 10:47.