Modern Brain Retractors and Surgical Brain Injury: A Review.

Surgical brain injury caused by brain retraction is a well-known consequence of intracranial surgery. Modern retractor designs, particularly since the 1980s, have significantly improved ease of use, improved visibility for surgeons, and minimized retraction-induced injuries, though not yet been entirely eliminated. Today, brain retractors come in a broad range of styles, each with its own pros and cons regarding operational utility and patient safety. Which type is chosen for use depends on the surgical approach, lesion size and depth, cost, and surgeon preference. Traditionally, self-retaining brain retractors with moveable arms and 1 or more attachable blades made from malleable stainless steel or silicone rubber have been the tool of choice; however, recently tubular retraction systems that only require fixation to the head frame and cause less focal pressure damage than older retractors have gained in popularity for some cases. This review aims to address the history of brain retraction and discuss each of the commonly used brain retractor types, as well as some newer and less common varieties especially in terms of the extent of tissue damage typically caused as well as the types of injuries reported by the users.

Use of Minimally Invasive Tubular Retractors for Foramen Magnum Decompression of Chiari Malformation: A Technical Note and Case Series.

BACKGROUND: An intraoperative technique for foramen magnum decompression of Chiari malformation is presented. The technique uses minimal exposure tubular retractors attached to a flexible arm to keep the retractor in a fixed position, while allowing flexible angulation under fluoroscopic guidance. METHODS: Operations were performed between 2009 and 2018 on 22 patients with cerebellar tonsillar descent below the foramen magnum and a diagnosis of type I Chiari malformation. A linear durotomy was necessary, but only the outer layer of the dura was opened for some patients, which is less invasive than the traditional procedure where a durotomy is performed for both the inner and outer layers, and then a duraplasty is performed. RESULTS: The approach allowed access to a wide working area, minimized soft tissue exposure, and optimized extent of decompression. The postoperative imaging demonstrated satisfactory bony removal, and magnetic resonance imaging of the area with cerebrospinal (CSF) flow study showed good CSF flow across the foramen magnum. There was a low incidence of postoperative complications, and the average length of hospital stay was 1 day. For 19 of 22 cases, the symptoms completely resolved or markedly improved, and each of the patients who attended the last follow-up demonstrated syrinx resolution. CONCLUSIONS: Based on our experience with this technique, when used to assist in foramen magnum decompression of Chiari malformation I, the minimally invasive tubular retractor is a useful tool, providing the surgeon with enhanced visualization of the operative field, while reducing potential damage to tissue and optimizing surgical outcomes.