Risk factors and significance of post-operative edema in Parkinson Disease patients submitted to deep brain stimulation. A ten-year case series.

BACKGROUND: Peri-electrode edema after deep brain stimulation (DBS) surgery for Parkinson Disease (PD) has been reported in up to 100% of cases. The clinical significance of this finding is unclear, with most papers suggesting a benign course. The risk factors are also poorly defined. We aimed at defining the incidence rate, the clinical significance and the predictive factors of peri-electrode edema in patients undergoing DBS for PD. METHODS: We reviewed data of 119 patients treated with frameless stereotactic DBS for PD between 2012 and 2022 at our Institution. A mixed-technique targeting was adopted. Awake surgery was used in 64.7% cases; in most cases, microelectrode recording (MER) was adopted. The target was the subthalamic nucleus (STN) in 91.2% cases. RESULTS: Ninety patients were included. Postoperative edema related to lead placement was noticed in 40% patients after a median time of 2 days since surgery; in 88.9% of these cases, it was limited to subcortical white matter. Symptomatic edema was registered only in one case (1.1%), confirming previous reports on the benign clinical course. The only independent predictive factor for edema onset was asleep surgery (p = 0.0451). Notably, the use of directional electrodes was not associated with an increased risk of edema at multivariable analysis. Clinical parameters including age, and timing of CT scanning, did not affect edema onset. CONCLUSIONS: We confirmed the very low rate of symptomatic edema in DBS for PD. When feasible, awake DBS using MER is the ideal technique to reduce the risk of radiologic postoperative edema.

Intraoperative microelectrode recording during asleep deep brain stimulation of subthalamic nucleus for Parkinson Disease. A case series with systematic review of the literature.

The use of microelectrode recording (MER) during deep brain stimulation (DBS) for Parkinson Disease is controversial. Furthermore, in asleep DBS anesthesia can impair the ability to record single-cell electric activity.The purpose of this study was to describe our surgical and anesthesiologic protocol for MER assessment during asleep subthalamic nucleus (STN) DBS and to put our findings in the context of a systematic review of the literature. Sixty-three STN electrodes were implanted in 32 patients under general anesthesia. A frameless technique using O-Arm scanning was adopted in all cases. Total intravenous anesthesia, monitored with bispectral index, was administered using a target controlled infusion of both propofol and remifentanil. A systematic review of the literature with metanalysis on MER in asleep vs awake STN DBS for Parkinson Disease was performed. In our series, MER could be reliably recorded in all cases, impacting profoundly on electrode positioning: the final position was located within 2 mm from the planned target only in 42.9% cases. Depth modification > 2 mm was necessary in 21 cases (33.3%), while in 15 cases (23.8%) a different track was used. At 1-year follow-up we observed a significant reduction in LEDD, UPDRS Part III score off-medications, and UPDRS Part III score on medications, as compared to baseline. The systematic review of the literature yielded 23 papers; adding the cases here reported, overall 1258 asleep DBS cases using MER are described. This technique was safe and effective: metanalysis showed similar, if not better, outcome of asleep vs awake patients operated using MER. MER are a useful and reliable tool during asleep STN DBS, leading to a fine tuning of electrode position in the majority of cases. Collaboration between neurosurgeon, neurophysiologist and neuroanesthesiologist is crucial, since slight modifications of sedation level can impact profoundly on MER reliability.

Global Surgery: A 30-Year Bibliometric Analysis (1987-2017).

INTRODUCTION: There has been a growing interest in addressing the surgical disease burden in low- and middle-income countries (LMICs). Assessing the current state of global surgery research activity is an important step in identifying gaps in knowledge and directing research efforts towards important unaddressed issues. The aim of this bibliometric analysis was to identify trends in the publication of global surgical research over the last 30 years. METHODS: Scopus® was searched for global surgical publications (1987-2017). Results were hand-screened, and data were collected for included articles. Bibliometric data were extracted from Scopus® and Journal Citation Reports. Country-level economic and population data were obtained from the World Bank. Descriptive statistics were used to summarise data and identify significant trends. RESULTS: A total of 1623 articles were identified. The volume of scientific production on global surgery increased from 14 publications in 1987 to 149 in 2017. Similarly, the number of articles published open access increased from four in 1987 to 68 in 2017. Observational studies accounted for 88.7% of the included studies. The three most common specialties were obstetrics and gynaecology 260 (16.0%), general surgery 256 (15.8%), and paediatric surgery 196 (12.1%). Over two times as many authors were affiliated to an LMIC institution than to a high-income country (HIC) institution (6628, 71.5% vs 2481, 28.5%, P < 0.001). A total of 965 studies (59.5%) were conducted entirely by LMIC authors, and 534 (32.9%) by collaborations between HICs and LMICs. CONCLUSION: The quantity of research in global surgery has substantially increased over the past 30 years. Authors from LMICs seemed the most proactive in addressing the global surgical disease burden. Increasing the funding for interventional studies, and therefore the quality of evidence in surgery, has the potential for greater impact for patients in LMICs.

The Extracellular Matrix in Glioblastomas: A Glance at Its Structural Modifications in Shaping the Tumoral Microenvironment-A Systematic Review.

BACKGROUND AND AIM: While many components of the ECM have been isolated and characterized, its modifications in the specific setting of GBMs have only been recently explored in the literature. The aim of this paper is to provide a systematic review on the topic and to assess the ECM's role in shaping tumoral development. METHODS: An online literature search was launched on PubMed/Medline and Scopus using the research string "((Extracellular matrix OR ECM OR matrix receptor OR matrix proteome) AND (glioblastoma OR GBM) AND (tumor invasion OR tumor infiltration))", and a systematic review was conducted in accordance with the PRISMA-P guidelines. RESULTS: The search of the literature yielded a total of 693 results. The duplicate records were then removed (n = 13), and the records were excluded via a title and abstract screening; 137 studies were found to be relevant to our research question and were assessed for eligibility. Upon a full-text review, 59 articles were finally included and were summarized as follows based on their focus: (1) proteoglycans; (2) fibrillary proteins, which were further subdivided into the three subcategories of collagen, fibronectin, and laminins; (3) glycoproteins; (4) degradative enzymes; (5) physical forces; (6) and glioma cell and microglia migratory and infiltrative patterns. CONCLUSIONS: Our systematic review demonstrates that the ECM should not be regarded anymore as a passive scaffold statically contributing to mechanical support in normal and pathological brain tissue but as an active player in tumor-related activity.