Endoscopic versus stereotactic biopsies of intracranial lesions involving the ventricles.

Stereotactic biopsies of ventricular lesions may be less safe and less accurate than biopsies of superficial lesions. Accordingly, endoscopic biopsies have been increasingly used for these lesions. Except for pineal tumors, the literature lacks clear, reliable comparisons of these two methods. All 1581 adults undergoing brain tumor biopsy from 2007 to 2018 were retrospectively assessed. We selected 119 patients with intraventricular or paraventricular lesions considered suitable for both stereotactic and endoscopic biopsies. A total of 85 stereotactic and 38 endoscopic biopsies were performed. Extra procedures, including endoscopic third ventriculostomy and tumor cyst aspiration, were performed simultaneously in 5 stereotactic and 35 endoscopic cases. In 9 cases (5 stereotactic, 4 endoscopic), the biopsies were nondiagnostic (samples were nondiagnostic or the results differed from those obtained from the resected lesions). Three people died: 2 (1 stereotactic, 1 endoscopic) from delayed intraventricular bleeding and 1 (stereotactic) from brain edema. No permanent morbidity occurred. In 6 cases (all stereotactic), additional surgery was required for hydrocephalus within the first month postbiopsy. Rates of nondiagnostic biopsies, serious complications, and additional operations were not significantly different between groups. Mortality was higher after biopsy of lesions involving the ventricles, compared with intracranial lesions in any location (2.4% vs 0.3%, p = 0.016). Rates of nondiagnostic biopsies and complications were similar after endoscopic or stereotactic biopsies. Ventricular area biopsies were associated with higher mortality than biopsies in any brain area.

Sub-Perception and Supra-Perception Spinal Cord Stimulation in Chronic Pain Syndrome: A Randomized, Semi-Double-Blind, Crossover, Placebo-Controlled Trial.

BACKGROUND: The introduction of modern sub-perception modalities has improved the efficacy of spinal cord stimulation (SCS) in refractory pain syndromes of the trunk and lower limbs. The objective of this study was to evaluate the effectiveness of low and high frequency SCS among patients with chronic pain. MATERIAL AND METHODS: A randomised, semi-double-blind, placebo controlled, four period (4 × 2 weeks) crossover trial was conducted from August 2018 to January 2020. Eighteen patients with SCS due to failed back surgery syndrome and/or complex regional pain syndrome were randomised to four treatment arms without washout periods: (1) low frequency (40-60 Hz), (2) 1 kHz, (3) clustered tonic, and (4) sham SCS (i.e., placebo). The primary outcome was pain scores measured by visual analogue scale (VAS) preoperatively and during subsequent treatment arms. RESULTS: Pain scores (VAS) reported during the preoperative period was M (SD) = 8.13 (0.99). There was a 50% reduction in pain reported in the low frequency tonic treatment group (M (SD) = 4.18 (1.76)), a 37% reduction in the 1 kHz treatment group (M (SD) = 5.17 (1.4)), a 34% reduction in the clustered tonic settings group (M (SD) = 5.27 (1.33)), and a 34% reduction in the sham stimulation group (M (SD) = 5.42 (1.22)). The reduction in pain from the preoperative period to the treatment period was significant in each treatment group (p < 0.001). Overall, these reductions were of comparable magnitude between treatments. However, the modality most preferred by patients was low frequency (55% or 10 patients). CONCLUSIONS: The pain-relieving effects of SCS reached significance and were comparable across all modes of stimulation including sham. Sub-perception stimulation was not superior to supra-perception. SCS was characterised by a high degree of placebo effect. No evidence of carryover effect was observed between subsequent treatments. Contemporary neuromodulation procedures should be tailored to the individual preferences of patients.

Combination of Neuroendoscopic and Stereotactic Procedures for Total Resection of Colloid Cysts with Favorable Neurological and Cognitive Outcomes.

BACKGROUND: Despite a wide range of surgical procedures, an unresolved debate remains regarding which attempt is optimal for the treatment of colloid cysts in the third ventricle. In this article, we present a new combination of stereotactic and endoscopic techniques. METHODS: This prospective study includes 27 consecutive patients with symptomatic primary and recurrent colloid cysts. All cysts were removed via a neuroendoscope through a rostral transfrontal, transforaminal approach. The endoscope was supported by an additional cannula fixed in the stereotactic frame. Both tools were inserted into one lateral ventricle through two separate burr holes using stereotactic guidance. RESULTS: The median operating time was 135 minutes. All cysts were removed completely, and no mortality or permanent complications related to surgery occurred. The mean time of observation was 43.5 months (range, 3-78 months), and no clinical or radiologic recurrences were observed. One patient with a history of an infected ventriculoperitoneal shunt did not improve after cyst removal, but improved after subsequent reimplantation of the shunt. In all other cases, symptoms resolved (67%) or decreased (30%). Cognitive functions improved or remained unchanged in all 10 elective cases examined neuropsychologically before and after surgery. CONCLUSIONS: The techniques we describe for removal of colloid cysts are safe and effective, even for recurrent cases, and they provide 100% total resection, favorable cognitive outcomes, low risk of recurrence, and low risk of morbidity. The disadvantages of this method are a longer time for surgery and the need for more complex instrumentation compared with conventional endoscopic resection.

Motor cortex stimulation in patients with chronic central pain.

BACKGROUND: Motor cortex stimulation is one of the neuromodulation methods of treating refractory central neurogenic pain. OBJECTIVES: The aim of this study was to retrospectively evaluate the effects of motor cortex stimulation. MATERIAL AND METHODS: The study group consisted of 14 consecutive patients with thalamic pain, atypical facial pain, post-brachial plexus avulsion injury pain, phantom pain and pain in syringomyelia who were treated with motor cortex stimulation at the Department of Neurosurgery of the Military Research Hospital in Bydgoszcz, Poland, from 2005 to 2013. The procedures were conducted with the use of neurosurgical navigation and intraoperative neurophysiological monitoring. The outcomes were assessed in terms of visual analog scale scores. The long-term follow-up ranged from one to six years. RESULTS: A statistically significant reduction in the intensity of pain was noted in patients treated with motor cortex stimulation (pre-surgery median visual analog scale=9, short-term result median visual analog scale=3, p=0.0009; long-term result median visual analog scale=5, p=0.0036). Over the long term, with follow-ups ranging from one to six years, the results were excellent (over 80% reduction in pain) in 31% of the patients and satisfactory (50-80% reduction in pain) in 23% of the patients. Unsatisfactory pain control (less than 50%) was noted in 31% of the patients and no improvement was noted in 15%. Significantly better relief of pain was observed in the early postoperative period. In this series of patients, the highest efficacy of motor cortex stimulation was observed in post-stroke or post-hemorrhagic thalamic pain (5/7 patients-71%). Long-term outcomes were not related to the age or sex of the patient, the preoperative duration of the pain, or to the position or number of implanted electrodes. CONCLUSIONS: MCS significantly reduces the intensity of neurogenic pain. The best long-term results in the present study were achieved in patients with thalamic syndrome. No significant predictors were found for a successful final outcome. The authors consider appropriate selection of patients, accurate placement of the electrodes and frequent adjusting of the stimulation parameters to be important factors increasing the efficacy of MCS.

Endoscopic third ventriculostomy in treatment of hydrocephalus.

INTRODUCTION: Endoscopic third ventriculostomy (ETV) is a minimally invasive method of treatment of obstructive hydrocephalus (HCP). AIM: To investigate perioperative and intraoperative difficulties, failures and complications of ETV. MATERIAL AND METHODS: Seventy-three procedures of ETV were conducted in our department in the last 5 years on 69 patients with HCP of different etiology. In 4 patients we performed ETV twice. In 4 cases we used neuronavigation. In 6 cases ETV was performed in conjunction with endoscopic biopsy of the tumor. In 6 cases we had to repeat the procedure (4) or implant a ventriculo-peritoneal shunt (2) due to recurrence of symptoms. RESULTS: In our series we had 3 important complications: one thalamic injury and 2 intraventricular hemorrhages. In 4 cases we observed postoperative hyperthermia with the presence of meningeal symptoms. Two cerebrospinal fluid (CSF) leaks were secured with additional stitches and 2 CSF infections were treated with antibiotics. In 1 patient epileptic seizers were observed. Three others complained of nausea and vomiting. The initial success rate of ETV is 70%. CONCLUSIONS: Based on our material we conclude that ETV is a useful and helpful procedure in non-communicating HCP. It carries 4% perioperative risk of serious complications which can be reduced by proper selection of patients, detailed plan and skilful performance of surgery in experienced hands and meticulous postoperative care.