Large language model, AI and scientific research: why ChatGPT is only the beginning.

ChatGPT, a conversational artificial intelligence model based on the generative pre-trained transformer GPT architecture, has garnered widespread attention due to its user-friendly nature and diverse capabilities. This technology enables users of all backgrounds to effortlessly engage in human-like conversations and receive coherent and intelligible responses. Beyond casual interactions, ChatGPT offers compelling prospects for scientific research, facilitating tasks like literature review and content summarization, ultimately expediting and enhancing the academic writing process. Still, in the field of medicine and surgery, it has already shown its endless potential in many tasks (enhancing decision-making processes, aiding in surgical planning and simulation, providing real-time assistance during surgery, improving postoperative care and rehabilitation, contributing to training, education, research, and development). However, it is crucial to acknowledge the model's limitations, encompassing knowledge constraints and the potential for erroneous responses, as well as ethical and legal considerations. This paper explores the potential benefits and pitfalls of these innovative technologies in scientific research, shedding light on their transformative impact while addressing concerns surrounding their use.

The neurosurgical outpatient clinic: comparison between accesses in public and private activities.

BACKGROUND: Neurosurgical clinic assesses presence and extent of pathologies of central and peripheral nervous system or disorders affecting the spine, to identify most effective treatment and possible recourse to surgery. The aim of the study is to evaluate the appropriateness of request for a neurosurgical consult both in private and in public outpatient clinics. MATERIALS AND METHODS: We collected and analyzed all the reports of outpatient visits of public and private clinic over a period between January and December 2018. RESULTS: There were 0.62% real urgent visits in the public sector and 1.19% in the private sector (p = 0.05). Peripheral pathologies represented 12.53% and 6.21% of pathologies evaluated in public and private sector respectively (p < 0.00001). In addition, 15.76% of visits in public lead to surgery, while they represented 11.45% in private (p = 0.0003). CONCLUSIONS: No study is available comparing accesses of patients in neurosurgical outpatient clinics. In public clinic, visits are booked as urgent on the prescription of the general practitioner: in reality, only 5% of these visits were really confirmed as urgent by the specialist. Peripheral pathologies are more frequent in public clinic, while cranial pathologies are more frequent in private one. Patients with cranial pathologies prefer to choose their surgeon by accessing private clinic.

Bleeding risk evaluation in cerebral cavernous malformation, the role of medications, and hemorrhagic factors: a case-control study.

OBJECTIVE: Cerebral cavernous malformations (CCMs) are vascular lesions with an overall risk of rupture from 2% to 6% per year, which is associated with significant morbidity and mortality. The diagnostic incidence is increasing, so it is of paramount importance to stratify patients based on their risk of rupture. Data in the literature seem to suggest that specific medications, particularly antithrombotic and cardiovascular agents, are associated with a reduced risk of bleeding. However, the effect of the patient coagulative status on the cumulative bleeding risk remains unclear. The aim of this study was to assess the impact of different radiological, clinical, and pharmacological factors on the bleeding risk of CCMs and to assess the predictive power of an already validated scale for general bleeding risk, the HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol concomitantly). METHOD: This was a multicenter retrospective observational study. The authors collected imaging, clinical status, and therapy data on patients with bleeding and nonbleeding CCMs. Univariate analysis and subsequent multivariate logistic regression were performed between the considered variables and bleeding or nonbleeding status to identify potential independent predictors of bleeding. RESULTS: The authors collected data on 257 patients (46.7% male, 25.3% with bleeding CCMs). Compared with patients with nonbleeding lesions, those with bleeding CCMs were younger, less frequently had hypertension, and less frequently required antiplatelet drugs and beta-blockers (all p < 0.05). Bleeding lesions, however, had significantly higher median volumes (1050 mm3 vs 523 mm3 , p < 0.001). On multivariate analyses, after adjusting for age, history of hypertension and diabetes, and use of antiplatelet drugs or beta-blockers, lesion volume ≥ 300 mm3 was the only significant predictor of bleeding (adjusted OR 3.11, 95% CI 1.09-8.86). When the diagnostic accuracy of different volume thresholds was explored, volume ≥ 300 mm3 showed a limited sensitivity (36.7%, 95% CI 24.6%-50.0%), but a high specificity 78.2% (95% CI 71.3%-84.2%), with an area under the curve of 0.57 (95% CI 0.51-0.64). CONCLUSIONS: This study supports previous findings that the CCM volume is the only factor influencing the bleeding risk. Antithrombotic agents and propranolol seem to have a protective role against the bleeding events. A high HAS-BLED score was not associated with an increased bleeding risk. Further studies are needed to confirm these results.

Training models and simulators for endoscopic transsphenoidal surgery: a systematic review.

Endoscopic transsphenoidal surgery is a novel surgical technique requiring specific training. Different models and simulators have been recently suggested for it, but no systematic review is available. To provide a systematic and critical literature review and up-to-date description of the training models or simulators dedicated to endoscopic transsphenoidal surgery. A search was performed on PubMed and Scopus databases for articles published until February 2023; Google was also searched to document commercially available. For each model, the following features were recorded: training performed, tumor/arachnoid reproduction, assessment and validation, and cost. Of the 1199 retrieved articles, 101 were included in the final analysis. The described models can be subdivided into 5 major categories: (1) enhanced cadaveric heads; (2) animal models; (3) training artificial solutions, with increasing complexity (from "box-trainers" to multi-material, ct-based models); (4) training simulators, based on virtual or augmented reality; (5) Pre-operative planning models and simulators. Each available training model has specific advantages and limitations. Costs are high for cadaver-based solutions and vary significantly for the other solutions. Cheaper solutions seem useful only for the first stages of training. Most models do not provide a simulation of the sellar tumor, and a realistic simulation of the suprasellar arachnoid. Most artificial models do not provide a realistic and cost-efficient simulation of the most delicate and relatively common phase of surgery, i.e., tumor removal with arachnoid preservation; current research should optimize this to train future neurosurgical generations efficiently and safely.

Recurrent or junctional lumbar foraminal herniated disc in patients operated with trans pars microscopic approach.

This is a retrospective monocentric study. The aim of this study is to analyze the incidence of recurrent or junctional lumbar foraminal herniated disc, in patients treated with trans pars microsurgical approach. Foraminal lumbar disc herniation represents a challenging pathology for the spinal surgeon. The appropriate surgical approach still represents a matter of debate. Several open and minimally-invasive techniques have been developed, in order to allow a proper tissue exposure and preserving the vertebral stability. The trans pars approach has already been described as a possible alternative, allowing excellent exposure of the herniated fragment with minimum bone removal. While few studies have analyzed the very low rate of post-operative instability, no articles deal with the incidence of post-operative herniated disc recurrence or junctional disc herniation in patients treated with this technique. We enrolled 160 patients operated at our institution. A univariate and multivariate analysis of possible factors influencing outcome (age, sex, level and BMI) was performed. Outcome variables were recurrent or junctional herniated disc. At the end, 135 patients were analyzed. Of the 135 patients, six presented recurrent herniated disc (4.4%) and other three developed a junctional herniation (2.2%). The occurrence of junctional herniated disc or recurrent herniated disc was not influenced by the analyzed variables, both at univariate and at multivariate analyses. The trans pars approach presents a low rate of recurrence and junctional herniation. Age, sex, level, and BMI do not influence the recurrence rate, both at same level and at junctional level.

Transpars approach for L5-S1 foraminal and extra-foraminal lumbar disc herniations: technical note.

BACKGROUND: The short pars and the narrowed surgical corridor for far lateral L5S1 herniation make the transpars approach challenging. The aim of this study is to determine the feasibility, efficacy, and safety of the transpars microscopic approach for the treatment of L5-S1 foraminal and extraforaminal lumbar disc herniation. METHODS: From 2015 to 2019, patients with L5-S1 far lateral lumbar disc herniation were prospectively recruited. Drug intake, working days lost, NRS-leg, NRS-back, nerve-root palsy, Oswestry disability-index, Macnab criteria were recorded before surgery and at follow-up. Patients were seen at 1-6-12 months after surgery. Lumbar dynamic X-rays were performed at 6-12 months after surgery and again at 2-4 years after surgery. Key-steps of surgery are described. RESULTS: Fourteen patients were enrolled. NRS-leg and NRS-back scores significantly improved (from 7.93 to 1.43 and from 3.2 to 0.6, respectively; P<0.0001). Oswestry Score significantly decreased (from 63.14 to 19.36 at 12 months; P<0.0001). L5 Root palsy improved in all cases (from 3.72/5 to 5/5; P<0.0001). At 12-months, excellent or good outcome (Macnab criteria) was achieved in 12 (85.7%) and 2 (14.3%) patients, respectively. All patients who were not retired returned to work within 30 days after surgery. No recurrence, instability or re-operations occurred. CONCLUSIONS: The trans pars microscopic approach is feasible, safe, and effective for L5-S1 foraminal and extraforaminal disc herniation. During surgery, the key-point is the oblique working angle, directed caudally, parallel to L5 pedicle. The iliac crest does not seem to constitute an obstacle.

ß-Estradiol 17-acetate enhances the in vitro vitality of endothelial cells isolated from the brain of patients subjected to neurosurgery.

In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier, our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic implants. We hypothesized that the autologous origin of human brain microvascular endothelial cells (hBMECs) is the first requirement for the suitable coating to prevent the glial inflammatory response triggered by foreign neuroprosthetics. Therefore, this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurgery patients. Culturing adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these cells. The addition of 10 nM ß-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing, supporting the well-known protective role played by estrogens on microvessels. In particular, ß-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs, while it was not necessary for freshly isolated male-derived hBMECs; however, it did counteract the decay in the viability of the latter after thawing. The tumor-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed before and after two periods of cryopreservation. Despite the thermal stress, the hBMECs remained viable and suitable for re-freezing and storage for several months. This approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools, offering the potential to avoid additional surgical sampling for each patient.

Effects of a sphenopalatine ganglion block on postcraniotomy pain management: a randomized, double-blind, clinical trial.

OBJECTIVE: Postcraniotomy pain (PCP) is a common finding after neurosurgical procedures, occurring in as many 87% of patients. The sphenopalatine ganglion (SPG) has a pivotal role in several headache syndromes, and its anesthetic block is currently used in different clinical conditions with benefit. The aim of this study was to evaluate the efficacy of an SPG block (SPGB) via a transnasal approach as adjunctive therapy in reducing pain scores during the postcraniotomy period. METHODS: In this single-center, double-blind, randomized controlled trial, patients undergoing elective surgery with a supratentorial craniotomy were randomly assigned to a scalp block, local anesthetic infiltration of the wound, and systemic analgesia during the first 48 postoperative hours (standard therapy), or to standard therapy as well as an SPGB (experimental therapy). According to the available evidence, assuming a 50% reduction in the incidence of the main outcome in patients with an SPGB (vs standard treatment), 82 patients were needed to achieve 80% statistical power in an intent-to-treat analysis. Pain intensity was recorded during the first 180 postoperative days at selective time points (5 times in the hospital, 3 times by telephone interview) with different pain rating systems (a visual analog scale [VAS], numeric rating scale [NRS], and pain assessment in advanced dementia [PAINAD] scale), together with demographic, clinical, and surgical variables and complications. Heart rate and blood pressure were recorded during surgery. Differences in all variables were evaluated using a paired t-test and confirmed through Wilcoxon matched-pairs signed-rank and Kruskal-Wallis tests. RESULTS: No complications occurred among the 83 patients enrolled. Statistically significant differences were found in the mean VAS score at postoperative days 0 (p = 0.05), 2 (p = 0.03), and 3 (p = 0.03). The PAINAD scale score showed significant differences between groups at postoperative days 1 (p = 0.006), 2 (p = 0.001), 3 (p = 0.03), and 4 (p = 0.05). The proportion of patients reporting a VAS score ≥ 3 in the first day after surgery was lower in the SPGB group than in the standard treatment group (71.9% vs 89.5%), although this difference did not reach statistical significance. At postoperative day 180, 5 patients (2 in the control group, 3 in the treatment group) had developed chronic PCP (NRS score ≥ 3). CONCLUSIONS: SPGB is a safe and effective procedure as an adjunctive treatment for PCP management in elective supratentorial craniotomy during the first 4 postoperative days compared with standard therapy. Further studies are needed to better define the clinical impact of SPGB use and its indications. Clinical trial registration no.: NCT05136625 (ClinicalTrials.gov).

Does the Timing of the Surgery Have a Major Role in Influencing the Outcome in Elders with Acute Subdural Hematomas?

BACKGROUND: The incidence of traumatic acute subdural hematomas (ASDH) in the elderly is increasing. Despite surgical evacuation, these patients have poor survival and low rate of functional outcome, and surgical timing plays no clear role as a predictor. We investigated whether the timing of surgery had a major role in influencing the outcome in these patients. METHODS: We retrospectively retrieved clinical and radiological data of all patients ≥70 years operated on for post-traumatic ASDH in a 3 year period in five Italian hospitals. Patients were divided into three surgical timing groups from hospital arrival: ultra-early (within 6 h); early (6-24 h); and delayed (after 24 h). Outcome was measured at discharge using two endpoints: survival (alive/dead) and functional outcome at the Glasgow Outcome Scale (GOS). Univariate and multivariate predictor models were constructed. RESULTS: We included 136 patients. About 33% died as a result of the consequences of ASDH and among the survivors, only 24% were in good functional outcome at discharge. Surgical timing groups appeared different according to presenting the Glasgow Outcome Scale (GCS), which was on average lower in the ultra-early surgery group, and radiological findings, which appeared worse in the same group. Delayed surgery was more frequent in patients with subacute clinical deterioration. Surgical timing appeared to be neither associated with survival nor with functional outcome, also after stratification for preoperative GCS. Preoperative midline shift was the strongest outcome predictor. CONCLUSIONS: An earlier surgery was offered to patients with worse clinical-radiological findings. Additionally, after stratification for GCS, it was not associated with better outcome. Among the radiological markers, preoperative midline shift was the strongest outcome predictor.

Ideal trajectory for frontal ventriculostomy: Radiological study and anatomical study.

OBJECTIVE: Several techniques have been described to improve the accuracy of the freehand procedure for frontal ventriculostomy and reduce complications due to suboptimal placement or misplacement of the catheter tip. To date, none of the available studies have found a reliable, low cost and consistent technique. We aimed to provide a standardized protocol for freehand frontal ventriculostomy. METHODS: In the first part of the radiological study, 125 CT scans were used to measure the length of the catheter using 2 right-sided entry points. In the second part, a grid of 24 entry points on the frontal bone was used in 50 CT scans to record the distance from the cranial surface to the Foramen of Monro (FM). Ventriculostomy was performed on six cadaveric heads using a grid of 9 entry points, comparing a 5 ml syringe with the freehand technique to reach the target. RESULTS: The first part of the radiological study showed a length from the cranial surface to the FM was overall 67,38 ± 1,03 mm. For the second part, the mean length of the 24 selected points was 68,54 ± 2,73 mm without statistical difference. In the anatomical study, the FM was reached 8 times (14.8%) with the syringe vs 31 times (57.4%) with the freehand technique, and the ventricles 43 (79.6%) vs 37 (68.5%). The mean lengths from the skull to the FM were 71.33 ± 4.21 mm. CONCLUSIONS: In this study, we showed the optimal length of a frontal ventricular catheter. We have also demonstrated that the portion of the frontal bone above the superior temporal lines matches a sphere in which the center is the FM.

Functional outcome after transfer of brachialis on anterior interosseous and supinator on posterior interosseous nerves: A preliminary report.

OBJECTIVE: Traumatic spinal cord injury (SCI) resulting in tetraplegia is a leading cause of morbidity among young adults worldwide and its management remains challenging. Restoring hand function in these patients must be considered a top priority with great impact on their quality of life (QOL); although nerve and tendon transfer have been extensively described, type of procedure to be chosen is not standardized and few studies have determined the functional outcome of those procedure and their impact on QOL is still poorly assessed. We report a preliminary retrospective study regarding feasibility and functional outcomes of nerve transfer procedures including bilateral brachialis nerve on anterior interosseous nerve (AIN) and supinator branch on posterior interosseous nerve (PIN) for hand reanimation following SCI focusing on the impact of these procedures on QOL. METHODS: We performed a retrospective study involving patient sustained SCI and underwent nerve transfer of brachialis branch from musculocutaneous nerve on AIN and supinator branch from the trunk of the radial nerve on the PIN. We included 11 patients (14 limbs) with traumatic SCI resulting in C4 level tetraplegia in five patients, C5 in four and C6 and C7 in one case each, with a median age of 31.5 years underwent surgery at a median of 10 months after injury; including both transfers in 10 cases and AIN reanimation only in one. Functional assessment including medical research council (MCR) grade, graded redefined assessment of strength sensation and prehension (GRASSP) and spinal cord independence measure (SCIM) were performed at least 12 months follow up. RESULTS: Thirteen PIN innervated muscles achieved an MRC score ≥3/5 whereas AIN supplied muscles in 5 out of 15. GRASSP qualitative measure improved from a baseline value of 1 to 2, while quantitative measure passed from 1 to 3 after 12 months; the difference was statistically significant (p = .005 and p = .008, respectively). SCIM self-care sub-score also statistically significant improved from 3 to 4 at 12 months (p = .016). No complication or donor morbidity occurred. CONCLUSIONS: Functional performance has been significantly improved by nerve transfer procedures 1 year after surgery. Nerve transfers may represent a valuable option for the restoration of the hand function in patients with tetraplegia with minor or no morbidity.

The role of the craniotomy size in the surgical evacuation of acute subdural hematomas in elderly patients: a retrospective multicentric study.

BACKGROUND: Elderly patients operated for an acute subdural hematoma (ASDH) frequently have a poor outcome, with a high frequency of death, vegetative status, or severe disability (Glasgow Outcome Score, GOS, 1-3). Minicraniotomy has been proposed as a minimally invasive surgical treatment to reduce the impact of surgery in the elderly population. The present study aimed to compare the influence of the size of the craniotomy on the functional outcome in patients undergoing surgical treatment for ASDH. METHODS: We selected patients ≥70 years old admitted to 5 Italian tertiary referral neurosurgical for the treatment of a post-traumatic ASDH between January 1st 2016 and December 31st 2019. We collected demographic data, clinical data (GCS, GOS, Charlson Comorbidity Index-CCI, antiplatelet/anticoagulant therapy, neurological deficits, seizure, pupillary size, length of stay), surgical data (craniotomy size, dividing the patients into 3 groups based on the corresponding tertile, and surgery duration), radiological data (ASDH side and thickness, midline shift, other post-traumatic lesions, extent of ASDH evacuation) and we assessed the functional outcome at hospital discharge and 6-month follow-up considering GOS=1-3 as a poor outcome. ANOVA and Chi-squared tests and logistic regression models were used to assess differences in and associations between clinicalradiological characteristics and functional outcomes. RESULTS: We included 136 patients (76 males) with a mean age of 78±6 years. Forty-five patients underwent a small craniotomy, 47 a medium size, and 44 a large craniotomy. Among the different craniotomy size groups, there were no differences in gender, anticoagulant/antithrombotic therapy, CCI, side of ASDH, ASDH thickness, preoperative GCS, focal deficits, seizures, and presence of other posttraumatic lesions. Patients undergoing small craniotomies were older than patients undergoing medium-large craniotomies; ASDH treated with medium size craniotomy were thinner than the others; patients undergoing large craniotomies showed greater midline shift and a higher rate of anisocoria. The three groups did not differ for functional outcome and postoperative midline shift, but the length of surgery and the rate of >50% of ASDH evacuation were lower in the small craniotomy group. CONCLUSIONS: A small craniotomy was not inferior to larger craniotomies in determining functional outcomes in the treatment of ASDH in the elderly.

Preliminary Validation of FoRCaSco: A New Grading System for Cerebral and Cerebellar Cavernomas.

OBJECTIVE: Surgical indications for cerebral cavernous malformations (CCMs) remain significantly center- and surgeon-dependent; available grading systems are potentially limited, as they do not include epileptologic and radiologic data. Several experienced authors proposed a new grading system for CCM and the first group of patients capable of providing its statistical validation was analyzed. METHODS: A retrospective series of 289 CCMs diagnosed between 2008 and 2021 was collected in a shared anonymous database among 9 centers. The new grading system ranges from -1 to 10. For each patient with cortical and cerebellar cavernous malformations the grading system was applied, and a retrospective outcome analysis was performed. We proposed a score of 4 as a cutoff for surgical indication. RESULTS: Operated patients with a score ≥4 were grouped with non-operated patients with a score <4, as they constituted the group that received correct treatment according to the new grading system. Patients with a score ≥4, who underwent surgery and had an improved outcome, were compared to patients with a score ≥4 who were not operated (P = 0.04), and to patients with a score <4 who underwent surgery (P < 0.001). CONCLUSIONS: This preliminary statistical analysis demonstrated that this new grading would be applicable in surgical reality. The cutoff score of 4 correctly separated the patients who could benefit from surgical intervention from those who would not. The outcome analysis showed that the treated patients in whom the grading system has been correctly applied have a better outcome than those in whom the grading system has not been applied.

Functional outcome of patients with unstable single-level/two-level lumbar stenosis treated with decompression plus divergent screws (cortical bone trajectory) or percutaneous convergent pedicle screws.

BACKGROUND: The aim of this prospective comparative study was to assess the functional outcome in two groups of patients suffering from spinal lumbar instability and treated by decompression and stabilization with posterior lumbar interbody fusion using percutaneous pedicle screws (PCT) or a novel technique of divergent pedicle screws insertion using a cortical bone divergent trajectory (CBT). Functional outcome after surgery has been evaluated using Numeric Rating Scale (NRS), Modified Rankin Scale (MRS), Smiley-Webster Scale, and Oswestry Disability Index (ODI). METHODS: Seventy-two consecutive patients were treated at our department from February 2013 to February 2018 for one-two levels unstable stenosis with one-year follow-up. Forty-one patients were treated with percutaneous screws and thirty-one patients were treated with divergent cortical bone trajectory screws. Functional outcome and complications were analyzed with logistic regression analysis. No funding was received for this research. RESULTS: Pain significantly improved in both groups. Charlson Comorbidity Index (CCI≥3) was the only variable associated with increased risk of complications (OR=5.73, P=0.04). Patients with BMI≥27.4 (median value) and patients with percutaneous screws had an increased risk of a worse Smiley-Webster Score (OR=3.675; P=0.029 and OR=3.747; P=0.05, respectively). Patients with BMI≥27.4, patients with percutaneous screws and patients with more comorbidities (CCI≥3) showed a higher risk of presenting severe/crippling Oswestry Disability Index Score (OR=6; P=0.027, OR=10.747; P=0.04 and OR=6.310; P=0.043, respectively). CONCLUSIONS: Cortical bone trajectory screws technique could represent a valid alternative to the traditional percutaneous pedicle screws technique in posterior lumbar interbody fusion.

Surgical Treatment of Diffuse Idiopathic Skeletal Hyperostosis (DISH) Involving the Cervical Spine: Technical Nuances and Outcome of a Multicenter Experience.

STUDY DESIGN: Retrospective multicenter. OBJECTIVES: diffuse idiopathic skeletal hyperostosis (DISH) involving the cervical spine is a rare condition determining disabling aero-digestive symptoms. We analyzed impact of preoperative settings and intraoperative techniques on outcome of patients undergoing surgery for DISH. METHODS: Patients with DISH needing for anterior cervical osteophytectomy were collected. Swallow studies and endoscopy supported imaging in targeting bone decompression. Patients characteristics, clinico-radiological presentation, outcome and surgical strategies were recorded. Impact on clinical outcome of duration and time to surgery and different surgical techniques was evaluated through ANOVA. RESULTS: 24 patients underwent surgery. No correlation was noted between specific spinal levels affected by DISH and severity of pre-operative dysphagia. A trend toward a full clinical improvement was noted preferring the chisel (P = 0.12) to the burr (P = 0.65), and whenever C2-C3 was decompressed, whether hyperostosis included that level (P = 0.15). Use of curved chisel reduced the surgical times (P = 0.02) and, together with the nasogastric tube, the risk of complications, while bone removal involving 3 levels or more (P = 0.04) and shorter waiting times for surgery (P < 0.001) positively influenced a complete swallowing recovery. Early decompressions were preferred, resulting in 66.6% of patients reporting disappearance of symptoms within 7 days. One and two recurrences respectively at clinical and radiological follow-up were registered 18-30 months after surgery. CONCLUSION: The "age of DISH" counts more than patients' age with timeliness of decompression being crucial in determining clinical outcome even with a preoperative mild dysphagia. Targeted bone resections could be reasonable in elderly patients, while in younger ones more extended decompressions should be preferred.

Influence of nutritional status on the clinical outcome of patients with chronic subdural hematoma: a prospective multicenter clinical study.

BACKGROUND: Elderly patients present a higher risk of developing chronic subdural hematomas (CSDHs) together with increased risk of malnutrition. The nutritional status may affect outcomes, response to treatments, and prognosis. Influence on other kinds of diseases was investigated showing an increased risk of mortality, morbidity, and adverse outcomes. However, no studies are available on its possible role for the outcome of patients with CSDH. This study aims to evaluate a possible relationship between the nutritional status and the clinical outcome of patients who underwent CSDH surgery. METHODS: This is a multicenter prospective study enrolling all patients treated for CSDH. Demographic and clinical data were collected. For nutritional status evaluation, we used the Mini Nutritional Assessment (MNA). Chi-square test was used for comparing clinical variables of patients and logistic regression analysis was used for defining the impact of the aforementioned variables on the clinical outcome. RESULTS: We enrolled 178 patients. Modified Rankin scale (mRS) was 0-2 pre-operatively in 23.6% of patients and post-operatively in 61.2% of patients. Total assessment MNA score was >23.5 in 47.8% of patients. Ninety-three patients (52.2%) presented a normal nutritional status, 63 (35.4%) were at risk of malnutrition and 22 (12.4%) were malnourished. The mean follow-up was 2.6 months. Malnourished patients were at higher risk of a worse outcome (OR 81; CI = 9-750). CONCLUSION: This study suggests that nutritional status represents a strong predictor of outcome. Our results, albeit preliminary, demonstrated malnutrition is correlated to the risk of worse clinical outcome for patients undergoing surgery for chronic subdural hematoma. Further investigations with wider casuistry and multiple nutritional scores are required to validate our data.

A New Insight in Nonaneurysmal Subarachnoid Hemorrhage: The Potential Role of the Internal Jugular Veins.

BACKGROUND: Causes of the nonaneurysmal subarachnoid hemorrhage (na-SAH) are still debated. Many studies confirmed the possible involvement of the intracranial venous system, in particular variants of the basal vein of Rosenthal. STUDY OBJECT: The aim of this study is to investigate the role of extracranial venous system, in particular the jugular drainage, in the na-SAH pathophysiology. MATERIALS AND METHODS: This is a multicenter retrospective study including patients suffering from na-SAH who were radiologically screened to exclude vascular malformations. The course of the internal jugular veins was evaluated to reveal any stenosis (caliber reduction >80%). Particular attention was paid at the passage between the styloid process and the arch of C1 to detect possible compression. As a control group, we enrolled patients who underwent CT angiograms and/or cerebral DSAs in the past 2 years. RESULTS: We included 194 patients. The na-SAH group consisted of 94 patients, whereas the control group consisted of 100 patients. Fifty patients of the control group underwent a CT angiography for an ischemic cerebrovascular disease or trauma and 50 patients for an SAH due to a ruptured aneurysm. A significant jugular stenosis was found in 49 (52.1%) patients in the na-SAH group and in 18 (18%) patients in the control group. At univariate and multivariate analysis, the difference was statistically significant (p < 0.0001). CONCLUSIONS: This is the first study investigating the correlation between jugular stenosis and the occurrence of na-SAH. The impaired venous outflow due to reduced venous caliber could result in an engorgement of the upstream intracranial veins with transient hypertensive phases facilitating ruptures. Further larger prospective studies are necessary to confirm these data.

The P2X7 purinergic receptor in intervertebral disc degeneration.

Mechanisms involved in the development of intervertebral disc (IVD) degeneration are only partially known, thus making the implementation of effective therapies very difficult. In this study, we investigated P2X7 purinergic receptor (P2X7R), NLRP3 inflammasome, and interleukin (IL)-1ß expression in IVD specimens at different stages of disease progression, and during the in vitro dedifferentiation process of the primary cells derived thereof. We found that P2X7R, NLRP3, and IL-1ß expression was higher in the IVD samples at a more advanced stage of degeneration and in the expanded IVD cells in culture which partially recapitulated the in vivo degeneration process. In IVD cells, the P2X7R showed a striking nuclear localization, while NLRP3 was mainly cytoplasmic. Stimulation with the semiselective P2X7R agonist benzoyl ATP together with lipopolysaccharide treatment triggered P2X7R transfer to the cytoplasm and P2X7R/NLRP3 colocalization. Taken together, these findings support pathophysiological evidence that the degenerated disc is a highly inflamed microenvironment and highlight the P2X7R/NLRP3 axis as a suitable therapeutic target. The immunohistochemical analysis and the assessment of subcellular localization revealed a substantial expression of P2X7R also in normal disc tissue. This gives us the opportunity to contribute to the few studies performed in natively expressed human P2X7R so far, and to understand the possible physiological ATP-mediated P2X7R homeostasis signaling. Therefore, collectively, our findings may offer a new perspective and pave the way for the exploration of a role of P2X7R-mediated purinergic signaling in IVD metabolism that goes beyond its involvement in inflammation.

Use of the SpineJack direct reduction for treating type A2, A3 and A4 fractures of the thoracolumbar spine: a retrospective case series.

BACKGROUND: Compression injuries of the thoracolumbar spine without neurological impairment are usually treated with minimally invasive procedures. Intravertebral expandable implants represent an alternative strategy in fractures with low fragments' displacement. METHODS: Patients with A2, A3 and A4 fractures of the T10-L2 spinal segment without neurological impairment, fracture gap >2 mm, vertebra plana, pedicle rupture, pedicle diameter <6 mm, spinal canal encroachment ≥50%, and vertebral body spread >30% were treated with the SpineJack device. Patients with pathological/osteoporotic fractures were excluded. Demographic and fracture-related data were assessed together with vertebral kyphosis correction, vertebral height restoration/loss of correction and final kyphosis. The modified Rankin Scale (mRS), Oswestry Disability Index (ODI), Visual Analogue Scale (VAS), Smiley-Webster Pain Scale (SWPS) and EuroQol-5D (EQ-5D) were evaluated at 1 (-post), 6 and 12 months (-fup) after surgery. Statistical analysis was performed and p values ≤0.05 were considered significant. RESULTS: Fifty-seven patients were included in the study. Patients aged >60 years reported worse kyphosis correction (<4°) with more postoperative complications, while vertebral plasticity in younger patients, fragmentation-related greater remodeling in A3/A4 fractures, and treatments within 7 days of trauma determined superior wedging corrections, with better EQ-5D-post and mRS-fup. Cement leakages did not affect functional outcome, while female gender and American Society of Anesthesiologists (ASA) score of 3-4 were associated with worse ODI-fup and VAS-fup. Although fracture characteristics and radiological outcome did not negatively influence the clinical outcome, A2 fracture was a risk factor for complications, thus indirectly compromising both the functional and radiological outcome. CONCLUSION: With spread of <30%, the SpineJack is an alternative to minimally invasive fixations for treating A3/A4 thoracolumbar fractures, being able to preserve healthy motion segments in younger patients and provide an ultra-conservative procedure for elderly and fragile patients.

Patient specific Polymethyl methacrylate customised cranioplasty using 3D printed silicone moulds: Technical note.

INTRODUCTION: Cranioplasty after decompressive craniectomy can be performed with several techniques and materials. With the common use of 3D printing, custom cranioplasty can be produced at affordable cost. Aim of this technical note is to describe our technique for producing patient specific Polymethyl methacrylate (PMMA) cranioplasty using 3D printed silicone moulds. MATERIALS AND METHODS: We enrolled seven patients from January 2020 to June 2021 who required surgery for cranioplasty. The 3D printing was used to produce silicone moulds for defining the exact shape of the PMMA cranioplasty, according to the CT scan of the patient. RESULTS: We performed seven procedures. The mean time of the surgery was 80 min. All cranioplasties perfectly matched the patient specific anatomy. No complications occurred. CONCLUSIONS: Using 3D printed patient specific silicone moulds and PMMA resulted to be effective, with affordable costs and ensuring a good cosmetic result.