Nguyen Ha Son, Doan Ninh, Gelsomino Michael, Shabani Saman, Mueller Wade
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, USA.
Surg Neurol Int. 2016 Feb 10;7(Suppl 4):S121-4. doi: 10.4103/2152-7806.176133. eCollection 2016.
When wounds are benign, diagnosis of deep brain stimulation (DBS) electrode infection and associated intraparenchymal infection can be challenging. Only a couple, such cases exist in literature. Since infections of the central nervous system can be life-threatening, prompt diagnosis is necessary to prevent neurological injury. Employed within the appropriate context, magnetic resonance imaging (MRI) of the brain, as well as laboratory data and clinical presentation, may help guide diagnosis.
Case 1 - A 55-year-old male with bilateral DBS electrodes and generators (49 days from last procedure), who presented with confusion and fever. Pertinent positive laboratory was white blood cell 20.5K. MRI of the brain showed edema with enhancement along the right DBS electrode. Wound exploration revealed gross purulence in the subgaleal space. The entire system was removed; cultures from subgaleal space revealed Propionibacterium acnes; cultures from electrode were negative. The patient was sent home on antibiotics. Case 2 - A 68-year-old male with a right DBS electrode (11 days from placement), who presented after an unwitnessed fall, followed by confusion and amnesia. Pertinent laboratory examinations were negative. MRI of the brain showed edema with enhancement along the DBS electrode. Wound exploration revealed no infection. The DBS system was left in place; final cultures were negative; no antibiotics were prescribed. Repeat MRI showed resolving fluid-attenuated inversion recovery (FLAIR) signal and contrast enhancement.
Contrast enhancement, T2 FLAIR, and diffusion weighted imaging are influenced by postoperative changes. Caution is stressed regarding dependence on these features for acute diagnosis of infection and indication for electrode removal. Timing of the imaging after surgery must be considered. Other factors, such as systemic signs and abnormal laboratory data, should be evaluated. Based on these guidelines, retrospectively, the patient in Case 2 should not have been rushed for a wound exploration; close observation with serial imaging and laboratory data may have prevented an unnecessary procedure.
当伤口为良性时，诊断脑深部电刺激（DBS）电极感染及相关脑实质内感染可能具有挑战性。文献中仅有少数此类病例。由于中枢神经系统感染可能危及生命，因此需要及时诊断以预防神经损伤。在适当的情况下，脑部磁共振成像（MRI）以及实验室数据和临床表现可能有助于指导诊断。
病例1 - 一名55岁男性，植入双侧DBS电极和发生器（距上次手术49天），出现意识模糊和发热。相关阳性实验室检查结果为白细胞20.5K。脑部MRI显示右侧DBS电极沿线有强化的水肿。伤口探查发现帽状腱膜下间隙有明显脓性分泌物。整个系统被移除；帽状腱膜下间隙培养物显示痤疮丙酸杆菌；电极培养物为阴性。患者出院时带抗生素。病例2 - 一名68岁男性，植入右侧DBS电极（植入后11天），在一次无人目睹的跌倒后出现意识模糊和失忆。相关实验室检查均为阴性。脑部MRI显示DBS电极沿线有强化的水肿。伤口探查未发现感染。DBS系统保留原位；最终培养物为阴性；未开抗生素。重复MRI显示液体衰减反转恢复（FLAIR）信号和对比增强消退。
对比增强、T2 FLAIR和扩散加权成像受术后变化影响。强调在依赖这些特征进行感染的急性诊断和电极移除指征时要谨慎。必须考虑术后成像的时间。应评估其他因素，如全身症状和异常实验室数据。根据这些指导原则，回顾性来看，病例2中的患者本不应匆忙进行伤口探查；通过连续成像和实验室数据进行密切观察可能会避免不必要的手术。
