Department of Neurosurgery, University of the Witwatersrand, Johannesburg, South Africa.
Department of Paediatric Neurosurgery, Nelson Mandela Children's Hospital, 6 Jubilee Rd, Parktown, Johannesburg, 2193, South Africa.
Childs Nerv Syst. 2021 May;37(5):1515-1523. doi: 10.1007/s00381-021-05101-2. Epub 2021 Mar 8.
Frameless stereotactic navigation is used to direct the trajectory and biopsy site of target lesions. We report on a novel intra-operative stimulating (IOS) probe that is integrated into a commercially available stereotactic biopsy needle with the rationale that stimulation of the intended biopsy site should predict functional tissue thus preventing inadvertent biopsy of eloquent tissue.
Patients undergoing brainstem biopsies for atypical lesions were offered the additional stimulation procedure. The IOS probe was used to deliver stimulation in an attempt to determine the proximity of eloquent tissue. Once the desired location of the biopsy needle was achieved, the IOS probe was inserted down the centre of the biopsy needle and the stimulus applied. If no action potential was recorded, biopsies from four quadrants of the lesion were taken. If however a compound action potential was recorded, a new target was selected.
Nine patients had the biopsy and stimulation procedure performed. The median age was 36 months. A minimum of 8 samples were obtained from each patient. Biopsy material was adequate to obtain a diagnosis in all 9 patients. In 2 cases use of the device influenced the insertion trajectory or biopsy site. No patients experienced any complications directly attributable to either the biopsy procedure or application of the stimulation.
Use of the IOS probe for intra-operative stimulation of the intended brainstem biopsy site was found to be safe and feasible. The addition of stimulation using the IOS probe can be done with minimal change in workflow.
无框架立体定向导航用于引导目标病变的轨迹和活检部位。我们报告了一种新型的术中刺激（IOS）探头，它集成到一种商业上可获得的立体定向活检针中，其基本原理是刺激预期的活检部位应该预测功能组织，从而防止无意中活检到重要组织。
为了进行脑干活检，对具有非典型病变的患者提供了额外的刺激程序。IOS 探头用于进行刺激，以试图确定重要组织的接近程度。一旦达到活检针的理想位置，就将 IOS 探头插入活检针的中心并施加刺激。如果没有记录到动作电位，则从病变的四个象限中取出活检样本。然而，如果记录到复合动作电位，则选择新的靶标。
有 9 名患者进行了活检和刺激程序。中位年龄为 36 个月。每个患者至少获得 8 个样本。9 名患者的活检材料均足以获得诊断。在 2 例中，该设备的使用影响了插入轨迹或活检部位。没有患者因活检过程或刺激的应用而直接出现任何并发症。
发现术中使用 IOS 探头刺激预期的脑干活检部位是安全可行的。使用 IOS 探头进行刺激的添加可以在最小改变工作流程的情况下完成。
