Change of Clinical and Radiologic Parameters after Minimally Invasive Decompression in Patients with Lumbar Spinal Stenosis: A Prospective Study with Long-term Follow-up

BACKGROUND

 The impact of minimally invasive decompression (MID) techniques on spinopelvic parameters and on the sagittal alignment remains a controversial topic. Here we studied the changes in clinical and radiologic parameters and their relationships in a series of lumbar spinal stenosis (LSS) submitted to MID with a minimum follow-up (FU) of 24 months.

METHODS

 We prospectively collected clinical and radiologic data of 20 consecutive patients who were evaluated preoperatively, at the 6-month FU, and at the 24-month FU. Visual analog scale (VAS) for back and leg pain, Oswestry disability index (ODI), neck disability index (NDI), sagittal vertical axis (SVA), C7 slope (C7S), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were assessed for each patient. Moreover, the percentage variation of clinical and radiologic factors at the 24-month FU compared with the preoperative factors was calculated to perform correlation studies among these variables.

RESULTS

 We reported a significant improvement of all clinical parameters. A significant increase of LL and SS and a significant decrease of PT and SVA were observed. The preoperative values of ODI, LL, SS, PT, and SVA significantly affect the 24-month FU values, and the percentage improvement of SVA at the 24-month FU compared with the preoperative values was significantly related to the percentage improvement of LL.

CONCLUSIONS

 MID is clinically effective in patients with LSS and improves the spinopelvic parameters and the global sagittal balance of the spine. The preoperative spinal alignment affects the spinal alignment at FU. The improvement of SVA was strictly related to the improvement of LL.

An Overview of Recent Advances in Anterior Cervical Decompression and Fusion Surgery

Anterior cervical diskectomy and fusion (ACDF) has evolved significantly in the last few years with the aim of enhancing effectiveness and safety while reducing hospitalization and healthcare-related costs. Transitioning from iliac crest autografts to allografts minimizes donor-site complications like pain, infections, and hematoma. Allograft options, such as polyetheretherketone (PEEK) and tantalum, vary in their osteoinductive properties and elastic modulus, influencing fusion rates, time, and the rate of subsidence. Recently introduced zero-profile cages offer bone fixation through screws, resulting in reduced blood loss, improved spinal alignment, and decreased complications like dysphagia and adjacent segment disease. Intraoperative neuromonitoring (IONM) has gained widespread use. The North American Spine Society (NASS) 2023 recommendations endorse IONM in cervical deformity corrections and myelopathy cases. Insufficient studies hinder clear radiculopathy recommendations, but emerging research supports IONM for patients at greater risk of C5 nerve root injury or positional injury. Advancements in hemostatic agents, such as gelatin sponges, oxidized cellulose, and fibrin sealants, contribute to safety by reducing postoperative hematoma rates and eliminating the need for drainage. Innovations like the exoscope, endoscope, and computed-tomography (CT) navigation have transformed surgical practices. Exoscopes are emerging as an alternative to microscopes, offering benefits like a smaller footprint, adjustable positioning, lower costs, and shared intraoperative views for educational purposes. The use of endoscope offers the possibility of performing a minimally invasive technique with improved results in terms of cosmesis and patient-perceived outcome. CT navigation can be useful in high-risk procedures, such as cervical plate placement for major instability. This paper provides an overview of cutting-edge technologies in ACDF surgery, emphasizing cage materials and designs, safety measures, and operating room advancements. It also highlights areas for future research, underlining the procedure's continuous evolution.

Predictive value of intraoperative vagus nerve corticobulbar motor evoked potentials to assess the risk of dysphagia in fourth ventricle surgery

OBJECTIVE

Dysphagia is a significant complication in fourth ventricle surgery. Corticobulbar motor evoked potentials (CB-MEPs) of the lower cranial nerves may provide real-time information possibly correlating with postoperative swallowing dysfunction, and the vagus nerves may prove ideal for this purpose. However, the literature is heterogeneous, non-systematic, and inconclusive on this topic. The object of this retrospective study was to evaluate the correlation between CB-MEPs of the vagus nerve and postoperative worsening or new-onset swallowing deficits in intraaxial fourth ventricle surgery.

METHODS

In 21 consecutive patients undergoing surgery for fourth ventricle intraaxial tumors between February 2018 and October 2022, endotracheal tubes with two applied electrodes contacting the vocal cords were used to record vagus nerve MEPs including values at baseline, the end of surgery, and the minimum value during the operation. From the mean value of right and left vagus nerve MEP amplitudes, the minimum-to-baseline amplitude ratio (MBR) and final-to-baseline amplitude ratio (FBR) were calculated. These indexes were correlated with postoperative swallowing function.

RESULTS

Given their clinical significance, receiver operating characteristic curves were obtained to evaluate the performance of these indexes in predicting postoperative swallowing function. The area under the curve (AUC) was 0.850 (p < 0.001) and the best cutoff for FBR was 67.55% for the worsening of swallowing in the postoperative period. The AUC was 0.750 (p = 0.026) and the best cutoff was 46.37% in MBR for the absence of a swallowing disorder at the late follow-up.

CONCLUSIONS

This study confirmed that vagus nerve MEPs are reliable predictors of postoperative swallowing function in fourth ventricle surgery and can be feasibly used as an intraoperative monitoring technique.

The impact of strategies to manage the COVID-19 pandemic on patients with intrathecal baclofen therapy

BACKGROUND

The activities related to intrathecal baclofen (ITB) therapy could not be interrupted at the outbreak of COVID-19 pandemic due to possible life-threatening related complications such as withdrawal and over dosage syndromes. In this study we reported the different adopted strategies to manage patients with an ITB implanted infusion pump during the pandemic period and studied the impact of these strategies on experiences reported from patients and their caregivers, assessed through a specific survey.

METHODS

Thirty-five patients (mean age: 43.71±12.33 years) were included. Their clinical and medical data were recorded and observed from March 2020 to March 2021 and different strategies implemented in order to limit patients and providers risk of exposure to COVID-19. The impact of these strategies was assessed trough a survey that was performed after the first two months of pandemic (coinciding with the period of general lockdown) and after one year from the pandemic onset.

RESULTS

We observed a statistically significant improvement of the following items: difficulties in reaching medical clinic (P=0.0072), continuation of physical therapy (P=0.0021) and feelings of anxiety in medical conditions (P=0.0006). Considering the difficulties in communications with the medical staff we obtained optimal scores both at the beginning of pandemic and after one year from the pandemic onset without significant difference.

CONCLUSIONS

Our survey showed that the adopted strategies provided a feeling of confidence and safety among ITB patients and their caregivers during the COVID-19 pandemic. We think that a clear communication is always of paramount importance to manage these patients.

Neuromodulation for Brain Tumors: Myth or Reality? A Narrative Review

In recent years, research on brain cancers has turned towards the study of the interplay between the tumor and its host, the normal brain. Starting from the establishment of a parallelism between neurogenesis and gliomagenesis, the influence of neuronal activity on the development of brain tumors, particularly gliomas, has been partially unveiled. Notably, direct electrochemical synapses between neurons and glioma cells have been identified, paving the way for new approaches for the cure of brain cancers. Since this novel field of study has been defined "cancer neuroscience", anticancer therapeutic approaches exploiting these discoveries can be referred to as "cancer neuromodulation". In the present review, we provide an up-to-date description of the novel findings and of the therapeutic neuromodulation perspectives in cancer neuroscience. We focus both on more traditional oncologic approaches, aimed at modulating the major pathways involved in cancer neuroscience through drugs or genetic engineering techniques, and on electric stimulation proposals; the latter is at the cutting-edge of neuro-oncology.

Is There a Role for Intraoperative Neuromonitoring in Intradural Extramedullary Spine Tumors? Results and Indications from an Institutional Series

While intraoperative neurophysiological monitoring (IONM) is considered a standard for intramedullary spinal cord tumor surgery, the effective role of IONM in intradural extramedullary (IDEM) tumors is still debated. We present the results of 60 patients affected by IDEM tumors undergoing surgery with the aid of IONM. Each patient was evaluated according to the modified McCormick scale (MMS) at admission, discharge and at follow-up. During surgery, motor evoked potentials (MEPs) and somatosensory evoked potentials (SEPs) were studied using the Medtronic NIM-eclipse^® 32-channel system (Medtronic Xomed, Inc. 6743 Southpoint Drive North Jacksonville FL USA). Patients' age, gender and tumor location did not affect MMS modifications. Tumors involving more than three levels had an increased likelihood of MMS worsening, while meningioma pathology was associated with worse preoperative and 1-year follow-up MMS. No MEP amplitude ratio was able to predict clinical variations, while intraoperative SEP worsening was associated with 100% risk of poor MMS at discharge and with 50% risk of poor MMS at long-term follow-up. In our opinion, SEP monitoring is a valid tool that may contribute to the preservation of the patient's neurological status. MEP monitoring is not mandatory in IDEM surgery while more studies are required to explore the feasibility and the role of D-wave in this kind of surgery.

CSF neuron-specific enolase as a biomarker of neurovascular conflict severity in drug-resistant trigeminal neuralgia: a prospective study in patients submitted to microvascular decompression

BACKGROUND

Although neurovascular conflict (NVC) is the most widely accepted cause of trigeminal neuralgia (TN), few articles have analyzed molecular and biochemical mechanisms underlying TN. In the present study, we dosed neuron-specific enolase (NSE) on serum and CSF samples of 20 patients submitted to microvascular decompression (MVD) and correlated these findings with the type of NVC.

METHODS

Blood samples were obtained preoperatively and 48 h after MVD. CSF from trigeminal cistern was intraoperatively obtained. NSE levels were measured using the Diasorin kit (LIAISON®NSE). NVC was classified as "contact" or "trigeminal nerve distortion/indentation" or "trigeminal root atrophy" based on MRI and intraoperative findings. Clinical outcome was measured by acute pain relief (APR) and Barrow Neurological Institute (BNI) scale at last available follow-up (FU; 6.40 ± 5.38 months).

RESULTS

APR was obtained in all patients. A statistically significant BNI reduction was obtained at latest FU (p < 0.0001). Serum NSE levels significantly decreased following MVD (from 12.15 ± 3.02 ng/mL to 8.95 ± 2.83 ng/mL, p = 0.001). The mean CSF NSE value was 48.94 ng/mL, and the mean CSF/serum NSE rate was 4.18 with a strong correlation between these two variables (p = 0.0008). CSF NSE level in "trigeminal root atrophy" group was significantly higher compared to "contact" (p = 0.0045) and "distortion/indentation" (p = 0.010) groups.

CONCLUSION

NSE levels seem to be related to the etiopathology and severity of NVC. A significant reduction of serum NSE levels could be related to the resolution of the NVC and clinical TN improvement.

Outcome Comparison of Drug-Resistant Trigeminal Neuralgia Surgical Treatments-An Umbrella Review of Meta-Analyses and Systematic Reviews

Medical treatment for trigeminal neuralgia (TN) is not always a feasible option due to a lack of full response or adverse effects. Open surgery or percutaneous procedures are advocated in these cases. Several articles have compared the results among different techniques. Nevertheless, the findings of these studies are heterogeneous. Umbrella reviews are studies sitting at the peak of the evidence pyramid. With this umbrella review, we provided a systematic review of the outcomes of the surgical procedures used for TN treatment. Only systematic reviews and meta-analyses were included following the PRISMA guidelines. Ten articles were enrolled for qualitative and quantitative assessment. Level of evidence was quantified using a specific tool (AMSTAR-2). Results were heterogenous in terms of outcome and measurements. Microvascular decompression (MVD) appeared to be the most effective procedure both in the short-term (pain relief in 85-96.6% of cases) and long-term follow-up (pain relief in 64-79% of cases), although showed the highest rate of complications. The results of percutaneous techniques were similar but radiosurgery showed the highest variation in term of pain relief and a higher rate of delayed responses. The use of the AMSTAR-2 tool to quantify the evidence level scored three studies as critically low and seven studies as low-level, revealing a lack of good quality studies on this topic. Our umbrella review evidenced the need of well-designed comparative studies and the utilization of validated scales in order to provide more homogenous data for pooled-analyses and meta-analyses in the field of TN surgical treatment.

Predictors of response to vagus nerve stimulation in drug resistant epilepsy

LETTER TO EDITOR Keywords.

Percutaneous Balloon Compression for Trigeminal Neuralgia. A Comparative Study Between the Fluoroscope Guided and Neuronavigated Technique

Percutaneous balloon compression (PBC) is a safe and effective procedure in the treatment of trigeminal neuralgia (TN) due to its simplicity, low cost and the possibility of being repeated in case of pain recurrence. Foramen ovale (FO) cannulation is accomplished with the assistance of intraoperative C-arm fluoroscopy. Recently, several authors have reported successful application of intraoperative CT navigation as well. The reported advantages of CT navigation are linked to better spatial orientation and the low rate of attempts for FO cannulation. However, these advantages should be considered in the face of concerns regarding increased radiation dose to the patient and its possible adverse effects. Here we compared the fluoroscopic guided and neuronavigated PBC techniques in terms of efficacy and radiological exposure. We retrospectively analyzed 37 patients suffering for TN and submitted to PBC. We observed a significant improvement of pain at 1 month FU compared with the pre-operative in both groups (p < 0.0001 and p < 0.0001, respectively). A significant increase in radiation exposure was found in the neuronavigated group compared with the fluoroscopy group (p < 0.0001). We suggest the use of neuronavigated PBC only in selected cases, such as patients with multiple previous operations, in whom a difficult access can be pre-operatively hypothesized.

Spinal Cord High-Frequency Stimulation. The Current Experience and Future Directions

Spinal cord stimulation (SCS) is a neuromodulation technology that has emerged as a valid treatment for chronic intractable neuropathic pain. After conventional tonic SCS, new waveforms of stimulation, like high frequency (HF), have proved that they can provide safe and effective pain relief. In addition, SCS is now being utilized more broadly as a potential treatment for a range of indications, including motor disorders and spasticity. Our study presents a retrospective analysis of 20 patients with heterogenous aetiologies of neuropathic pain treated with HF stimulation, after a standardized protocol in a temporary trial. We observed a significant improvement in pain relief according to comparisons of numerical rating scale (NRS) scores before the procedure, after the clinical trial and at latest follow-up. Two unusual clinical cases were also reported, and the pertinent literature was discussed.

Methods and Principles of the Intraoperative Neurophysiologic Monitoring in Neurosurgery

Intraoperative neurophysiologic monitoring (IONM) is an innovation introduced in neurosurgery in the past decades. It aims to support and guide the neurosurgeon to obtain the best surgical result possible, preventing the occurrence of neurological deficits. The somatosensory evoked potentials (SSEP) assess the integrity of the sensory pathways monitoring the dorsal column-medial lemniscus pathway during spine and cerebral surgery. Motor evoked potentials (MEPs) provide information on the integrity of the motor pathway monitoring the efferent motor pathways from the motor cortex to the muscle through corticospinal (or corticobulbar) tracts. Free-running EMG is the standard technique to monitor peripheral nerves, roots, or cranial motor nerves during surgery. Intraoperative EMG signals are activated during cranial motor nerves damaging or after an irritative stimulus. The duration, morphology, and persistence of EMG reflects the severity of neural injury. Nerve mapping consists of recording muscle activations given by direct nerve stimulation. This technique makes use of a stimulation probe available to the neurosurgeon which allows administering current directly to the nervous tissue (nerves, roots, etc.). Intraoperative neurophysiological monitoring (IONM) represents the standard of care during many procedures, including spinal, intracranial, and vascular surgeries, where there is a risk of neurological damage. Close communication and collaboration between the surgical team, neurophysiologist, and anesthesiologist is mandatory to obtain high-quality neuromonitoring, thus preventing neurologic injuries and gaining the best surgical "safe" results.

Does Laminectomy Affect Spino-Pelvic Balance in Lumbar Spinal Stenosis? A Study Based on the EOS X-Ray Imaging System

PURPOSE

Lumbar spinal stenosis (LSS) is a degenerative disorder causing the forward bending of the trunk and pelvic retroversion with the consequent loss of lumbar lordosis; surgical treatment is intended to enlarge the canal and foramina and decompress the nerve roots. The purpose of our study is to determine whether and to what extent facet-sparing laminectomy affects the spino-pelvic balance.

METHODS

The spino-pelvic balance of 26 patients was analysed before and after surgery through the EOS X-ray Imaging System. The following parameters were considered: thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). Clinical data were expressed in numeric values according to the Oswestry Disability Index (ODI), the visual analogue scale (VAS) and the modified Japanese Orthopaedic Association (mJOA) scoring system.

RESULTS

Significant SS decreases and PT increases were noticed after surgery, without modification in LL, axial vertebral rotation (AVR) and the general alignment. Pain and disability had a significant improvement, as represented by a decrease in scores on the VAS and ODI scales and an increase in scores on the mJOA functional scale.

CONCLUSION

The most important parameter seems to be a congruence between pelvic and spinal parameters, which achieves an economic posture with the physiologic position of the axis of gravity. According to the literature, a standard sagittal balance (SB) has not been defined.

Intraoperative Corticobulbar Motor Evoked Potential in Cerebellopontine Angle Surgery: A Clinically Meaningful Tool to Predict Early and Late Facial Nerve Recovery

BACKGROUND

Intraoperative neuromonitoring is crucial for facial nerve preservation in cerebellopontine angle (CPA) surgery. Among the available techniques, the role of intraoperative corticobulbar facial motor evoked potentials (FMEPs) is unclear.

OBJECTIVE

To evaluate the significance of intraoperative FMEPs as indicators for early and late postoperative facial nerve function (FNF) in CPA tumor resection and the feasibility of their integration with standard monitoring techniques.

METHODS

An institutional series of 83 patients who underwent surgery under intraoperative monitoring for CPA extra-axial tumor resection was reported. A pair of needle electrodes was used to record FMEP from orbicularis oculi (OOc) and orbicularis oris (OOr) muscles at baseline, at the end of surgery and minimum values recorded. From FMEP amplitudes, minimum-to-baseline amplitude ratio (MBR), final-to-baseline amplitude ratio (FBR), and recovery value, intended as FBR minus MBR, were calculated. These indices were correlated with early and late postoperative FNF.

RESULTS

Our analysis demonstrated that higher FBR (both from OOc and OOr) and MBR (from OOr only) were associated with a good early and late FNF; a higher MBR from OOc was significantly associated with a good late FNF. The most accurate index in predicting early FNF was FBR measured from OOr with a cutoff of 35.56%, whereas the most accurate index in predicting late FNF was FBR as measured from OOc with a cutoff of 14.29%.

CONCLUSION

Our study confirmed that FMEPs are reliable predictors of early and late postoperative FNF in CPA surgery and could be easily integrated with standard intraoperative neuromonitoring techniques.

Factors associated with cerebrospinal fluid leak after a retrosigmoid approach for cerebellopontine angle surgery

Background

The retrosigmoid approach represents a crucial surgical route to address different lesions in the cerebellopontine angle but cerebrospinal fluid (CSF) leak still remains the most frequent complication after this approach. Here, we analyzed the impact of different factors in CSF leak development after a retrosigmoid approach. Identifying risk factors related to a specific approach may help the surgeon to tailor the perioperative management and to appropriately counsel patients regarding their risk profile.

Methods

We retrospectively reviewed the clinical, surgical, and outcome data of 103 consecutive patients (M/F, 47/56; mean follow-up 35.6 ± 23.9 months) who underwent a retrosigmoid approach for different cerebellopontine angle pathologies and studied the impact of different factors on the occurrence of a CSF leak to univariate and multivariate analysis.

Results

Seventy-nine patients (76.7%) were operated for tumors growing in the cerebellopontine angle. Twenty-four patients (23.2%) underwent microvascular decompression to treat a drug-resistant trigeminal neuralgia. Sixteen patients (15.5%) developed CSF leak in the postoperative course of which six underwent surgical revision. Performing a craniectomy as surgical procedure (P = 0.0450) and performing a reopening procedure (second surgery; P = 0.0079) were significantly associated to a higher risk of developing CSF leak. Moreover, performing a reopening procedure emerged as an independent factor for CSF developing on multivariate analysis (P = 0.0156).

Conclusion

Patients submitted to craniectomy and patients who underwent a second surgery showed an higher CSF leak rate. Ongoing improvement of biomaterial technology may help neurosurgeons to prevent this potentially life-threatening complication.

The Impact of Neuronavigation on the Surgical Outcome of Microvascular Decompression for Trigeminal Neuralgia

OBJECTIVE

Microvascular decompression (MVD) is considered the only etiological treatment for drug-resistant trigeminal neuralgia (TN). Nonetheless, despite the recent technological advances, the risks associated with MVD remain non-negligible. The aim of this study was to evaluate the impact of using neuronavigation on the surgical outcomes of patients with TN submitted for MVD.

METHODS

We analyzed 30 consecutive patients (11 men, 19 women) who underwent MVD for TN between January 2019 and December 2019. Patients were divided in 2 groups according to the use of neuronavigation (group A: MVD with neuronavigation; group B: MVD without neuronavigation). The impact of neuronavigation was assessed on the following parameters: craniotomy size, surgical duration, mastoid air cell opening, postoperative cerebrospinal fluid (CSF) leakage and other complications occurrence, and length of hospitalization. The acute pain relief and the Barrow Neurological Institute score at follow-up were used to evaluate the functional outcome.

RESULTS

The craniotomy size, the surgical duration, and the CSF leak incidence were significantly reduced in group A compared with group B (P = 0.0009, P = 0.0369, and P = 0.0406, respectively). The incidence of mastoid air cell opening, and the length of hospitalization were reduced in group A compared with group B, although these differences were not statistically significant. We obtained an acute pain relief in all cases, and the Barrow Neurological Institute score at follow-up was significantly reduced (P < 0.0001).

CONCLUSIONS

Neuronavigation is a useful tool that significantly reduced craniotomy size, surgical duration, and CSF leak incidence in patients with TN submitted for MVD. We advise to routinely implement neuronavigation in this type of surgery.

Clinical Application of a High Definition Three-Dimensional Exoscope in Anterior Lumbar Interbody Fusion: Technical Note

OBJECTIVES

Video-assisted telescope operating monitor (VITOM) or exoscope is currently applied in different surgical specialties with clear visualization advantages in terms of magnification, illumination, and wide field of view. The small and deep surgical field of anterior lumbar interbody fusion (ALIF) seemed to be an ideal setting to assess efficacy of exoscope, also considering limits related to microscopic and endoscopic visualization currently employed.

METHODS

We reported our preliminary experience with exoscope in 9 cases of ALIF at L5-S1 level. These data were retrospectively compared with those obtained from an equal sample of ALIF procedures performed with endoscope as visualization instrument. The technical aspects taken into account were time for procedure and blood loss. Reports from the surgeon about ergonomics and confidence with both techniques were also evaluated.

RESULTS

Exoscope proved, in our experience, good visualization and ergonomics and unobstructed access to a small and deep surgical field, allowing abundant space to insert and manipulate the instruments.

CONCLUSIONS

The instrument contained dimension and its long working distance, superior to endoscope and comparable with operating microscope, showed clear advantages of maneuverability. Moreover, the stereoscopic vision provided by 3-dimensional images proved to be crucial in hand-eye coordination.

Occupational exposure for asbestos-related disease groups: geomapping of the last 5 years in Italy

Background

Asbestos-related diseases are a public health challenge in Italy: the country has been a major producer and user of asbestos since World War II until complete ban in 1992. Several contaminated sites and structures across the country have never been decontaminated: incidence peak of asbestos-related diseases is expected somewhen between 2015 and 2020. Study objective is to investigate incidence of asbestos-related diseases in Italy in the last 5 years, from both a chronological and geographical perspective.

Methods

Ascertained diagnoses of asbestos-related diseases among workers were collected from the INAIL public registry from 2014 to 2018. Yearly incidence rate was estimated per province (incident cases per million workers) and mapped by year. Global incidence quota by working sector and sub-sector was also calculated.

Results

8.620 cases have been reported. Incidence rate rapidly increased from 2014, peaking at 7,2 new cases per 100.000 workers in 2015. Afterwards, the number of ascertained cases decreased. There is a clear gradient distribution between northern and southern Italian provinces, with the highest rates in Northern Italy (especially in year 2014) and declining over time. Mesothelioma (all variants) was the most common disease, (2.995 cases, 35% of total), followed by pleural plaques (2.955 cases, 34%), pneumoconiosis (1.327 cases, 15%) and cancer of lungs/respiratory tract (1.298 cases, 14%). Most affected category was that of metal workers, but construction, transportation and electricity workers were also affected.

Conclusions

Detailed surveillance with mapping support is an effective tool for public health servants to locally manage prevention programs targeted on occupational risk. This is especially true for areas with active industries in the most affected sectors.

Key messages

Asbestos does not mean mesothelioma, but also other diseases that impact on workforce health status. Pneumoconiosis and other oral and respiratory cancers are also associated with asbestos exposure. Risk management should be tailored for a wider array of worker types than usually considered, since such exposure happens in sectors that are not traditionally related to asbestos exposure.

The autopsy at the time of SARS-CoV-2: Protocol and lessons

A new viral disease named COVID-19 has recently turned into a pandemic. Compared to a common viral pneumonia it may evolve in an atypical way, causing the rapid death of the patient. For over two centuries, autopsy has been recognized as a fundamental diagnostic technique, particularly for new or little-known diseases. To date, it is often considered obsolete giving the inadequacy to provide samples of a quality appropriate to the sophisticated diagnostic techniques available today. This is probably one of the reasons why during this pandemic autopsies were often requested only in few cases, late and discouraged, if not prohibited, by more than one nation. This is in contrast with our firm conviction: to understand the unknown we must look at it directly and with our own eyes. This has led us to implement an autopsy procedure that allows the beginning of the autopsy shortly after death (within 1–2 h) and its rapid execution, also including sampling for ultrastructural and molecular investigations. In our experience, the tissue sample collected for diagnosis and research were of quality similar to biopsy or surgical resections. This procedure was performed ensuring staff and environmental safety. We want to propose our experience, our main qualitative results and a few general considerations, hoping that they can be an incentive to use autopsy with a new procedure adjusted to match the diagnostic challenges of the third millennium.

•

Early performed autopsy (within 1-2 hour from death) provides tissue samples for diagnosis and research of quality similar to biopsy or surgical resections.

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Early samples collection reduces post-mortem artifacts, thus preventing the wrong interpretation of the morphological pictures observed.

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Precise autopsy planning prevents risks for the staff.

Transpedicular Approach to Thoracic Disc Herniaton Guided by 3D Navigation System

BACKGROUND

The choice of surgical approach for thoracic disc herniation should consider the location on the axial plane and the consistency of the herniated disc. Calcified midline disc herniations are difficult to remove with a transpedicular approach because of limitations due to blind spots; so they are usually treated via a transthoracic approach, although this entails a high risk of thoracopulmonary injuries.

METHODS

In this work we present two cases of calcified midline thoracic disc herniations treated with a transpedicular approach, improved by using a three-dimensional (3D) neuronavigation system to verify the extent of removal on the blind side.

RESULTS

Postoperative computed tomography (CT) scans demonstrated that this original technical innovation, in the two present cases, allowed us to reach the side opposite the disc herniation and to assess the extent of resection at the end of the procedure.

CONCLUSIONS

The employment of a neuronavigation system in the transpedicular approach allowed safe and effective removal of calcified midline thoracic disc herniations. We did not observe any postoperative neurological worsening, onset of spinal instability, or other adverse events.

Tumors of the peripheral nervous system: analysis of prognostic factors in a series with long-term follow-up and review of the literature

OBJECT

Only a few published studies of the surgical treatment of benign peripheral nerve sheath tumors (BPNSTs), malignant peripheral nerve sheath tumors (MPNSTs), and peripheral non–neural sheath tumors (PNNSTs) have analyzed the results and possible prognostic factors using multivariate analysis. The authors report on their surgical series of cases of BPNSTs, MPNSTs, and PNNSTs with long-term follow-up and analyze the role of selected factors with respect to the prognosis and risk of recurrence of these tumors using multivariate analysis. They also review the pertinent literature and discuss their results in its context.

METHODS

The authors retrospectively reviewed data from cases involving patients who underwent resection of a peripheral nerve tumor between January 1983 and December 2013 at their institution. Of a total of 200 patients, 150 patients (with 173 surgically treated tumors) had adequate follow-up data available for analysis. Pain was assessed using a visual analog scale (VAS), and motor and sensory function were assessed by means of the Louisiana State University grading system. They also analyzed the relationship between tumor recurrence and patient sex, patient age, diagnosis of neurofibromatosis (NF), tumor histopathology, tumor size, tumor location, and extent of resection (subtotal vs gross-total resection), using univariate and multivariate analyses.

RESULTS

There was a statistically significant improvement in the mean VAS pain score (preoperative 3.96 ± 2.41 vs postoperative 0.95 ± 1.6, p = 0.0001). Motor strength and sensory function were significantly improved after resection of tumors involving the brachial plexus (p = 0.0457 and p = 0.0043, respectively), tumors involving the upper limb (p = 0.0016 and p = 0.0016, respectively), BPNSTs (p = 0.0011 and p < 0.0001, respectively), and tumors with dimensions less than 5 cm (motor strength: p = 0.0187 and p = 0.0021 for ≤ 3 cm and 3–5 cm tumors, respectively; sensory function: p = 0.0003 and p = 0.0001 for ≤ 3 cm and 3–5 cm tumors, respectively). Sensory function showed a statistically significant improvement also in patients who had undergone resection of tumors involving the lower limb (p = 0.0118). Total resection was associated with statistically significant improvement of motor strength (p = 0.0251) and sensory function (p < 0.0001). In univariate analysis, a history of NF (p = 0.0034), a diagnosis of MPNST or PNNST (p < 0.0001), and subtotal resection (p = 0.0042) were associated with higher risk of tumor recurrence. In multivariate analysis (logistic regression analysis), a history of NF (OR 9.28%, 95% CI 1.62–52.94, p = 0.0121) and a diagnosis of MPNST (OR 0.03%, 95% CI 0.002–0.429, p = 0.0098) or PNNST (OR 0.081%, 95% CI 0.013–0.509, p = 0.0077) emerged as independent prognostic factors for tumor recurrence.

CONCLUSIONS

A total resection should be attempted in all cases of peripheral nervous system tumors (irrespective of the supposed diagnosis and tumor dimensions) because it is associated with better prognosis in term of functional outcome and overall survival. Moreover, a total resection predicts a lower risk of tumor recurrence. Patients with a history of NF and tumors with malignant histology remain a challenge both for neurosurgeons and oncologists due to higher recurrence rates and the lack of standardized adjuvant therapies.

Facial--hypoglossal nerve end-to-side neurorrhaphy: anatomical study in rats

End-to-side neurorrhaphy (ESN) is presented as a sort of surgical technique for nerve repair that has the aim to obtain a good reinnervation of the recipient nerve and function preservation of the donor nerve. Several problems regarding this technique remain to be solved. Even if ESN could find some indications in particular cases of peripheral nerve surgery, we do not think that this technique can be first choice surgery for repairing a damaged facial nerve because of the complexity of the function of facial muscles and the necessity to offer an adequate number of motoneurons from the donor nerve for reinnervation of the recipient nerve.So, despite some reports about the clinical use of facial-hypoglossal nerve ESN, we studied experimentally such technique in the rat, having as recipient the facial nerve and as donor the hypoglossus. The purpose was to establish the number of motoneurons with which the donor hypoglossal nerve innervates the recipient facial nerve, and to compare the result with that obtained after facial-hypoglossus end-to-end neurorrhaphy (EEN). Beside other interesting findings, the key point of the obtained results was that motoneuron contribution given from the donor hypoglossus to the innervation of the recipient facial nerve was limited in ESN as compared to the classic EEN.

Survival following treatment for intracranial ependymoma: a review

The actual definition of survival rates following treatment for intracranial ependymomas is substantially influenced by the strict interaction among different factors. Age, location, and grading, for example, act together, negatively influencing the prognosis of younger children also invariably influenced by the more demanding role of surgery and the still limited use, up to recently, of radiotherapy under 3 years of age. In the same direction, the worse prognosis in most series of infratentorial ependymomas if compared with their supratentorial counterpart should be cautiously considered, midline posterior fossa tumors having completely different implications from those originating or predominantly extending to the cerebellopontine angle, where the extent of surgery has more invariably to compare with patients' quality of life. New radiotherapic regimens and their applications in infancy are promisingly demonstrating an improvement of present prognostic criteria, with the limit of still insufficient information on their long-term secondary effects. Similarly, molecular biology research studies, though still in their preclinical stage, are prompting to change the concept of a substantially chemoresistant tumor helping to stratify these lesions with the final aim of targeted pharmacological therapies. In the present review paper, we investigated singularly the role that the more commonly considered prognostic factors have had in the literature on survival of children affected by intracranial ependymomas, trying to elucidate their cumulative effect on the actual knowledge of this issue.

Linkage analysis of candidate regions using a composite neurocognitive phenotype correlated with schizophrenia

As schizophrenia is genetically and clinically heterogeneous, systematic investigations are required to determine whether ICD-10 or DSM-IV categorical diagnoses identify a phenotype suitable and sufficient for genetic research, or whether correlated phenotypes incorporating neurocognitive performance and personality traits provide a phenotypic characterisation that accounts better for the underlying variation. We utilised a grade of membership (GoM) model (a mathematical typology developed for studies of complex biological systems) to integrate multiple cognitive and personality measurements into a limited number of composite graded traits (latent pure types) in a sample of 61 nuclear families comprising 80 subjects with ICD-10/DSM-IV schizophrenia or schizophrenia spectrum disorders and 138 nonpsychotic first-degree relatives. GoM probability scores, computed for all subjects, allowed individuals to be partly assigned to more than one pure type. Two distinct and contrasting neurocognitive phenotypes, one familial, associated with paranoid schizophrenia, and one sporadic, associated with nonparanoid schizophrenia, accounted for 74% of the affected subjects. Combining clinical diagnosis with GoM scores to stratify the entire sample into liability classes, and using variance component analysis (SOLAR), in addition to parametric and nonparametric multipoint linkage analysis, we explored candidate regions on chromosomes 6, 10 and 22. The results indicated suggestive linkage for the familial neurocognitive phenotype (multipoint MLS 2.6 under a low-penetrance model and MLS>3.0 under a high-penetrance model) to a 14 cM area on chromosome 6, including the entire HLA region. Results for chromosomes 10 and 22 were negative. The findings suggest that the familial neurocognitive phenotype may be a pleiotropic expression of genes underlying the susceptibility to paranoid schizophrenia. We conclude that use of composite neurocognitive and personality trait measurements as correlated phenotypes supplementing clinical diagnosis can help stratify the liability to schizophrenia across all members of families prior to linkage, allow the search for susceptibility genes to focus selectively on subsets of families at high genetic risk, and augment considerably the power of genetic analysis.

Analysis of the 5' and 3'UTRs in the post-transcriptional regulation of the interleukin-5 gene

Post-transcriptional regulation is emerging as an important control point in cytokine gene expression. However, the role that it plays in IL-5 gene expression is unclear with some conflicting reports. Here we investigate the importance of post-transcriptional regulation and the role of the 5' and 3' untranslated regions (UTRs) in mIL-5 gene expression. To do this, IL-5 expression from a panel of cDNA constructs was compared. We found it essential to remove the 5' synthetic oligonucleotide tails, introduced during the cloning of the mIL-5 cDNA, when studying IL-5 expression. The presence of these oligo(G) tails acted as potent inhibitors of translation of both SV40 and SP6 transcripts. Furthermore, the length of the tails was found to be critical to the translational efficiency. Taking this into account, we found no evidence to suggest that IL-5 is regulated at the level of mRNA stability or translation efficiency by either the 5' or 3'UTR. These results suggest that post-transcriptional control is not a major factor regulating IL-5 expression.

Identification of two novel palindromic regulatory elements in the murine interleukin-5 promoter

Interleukin-5 has remarkable specificity for the eosinophil lineage. This fact, combined with the biological specificity of eosinophilia suggests tight and independent regulation of IL-5 expression. Here we report two novel palindromic regulatory elements (PRE) which contain positive regulatory motifs (PRM) that control transcription of the murine IL-5 gene. The first element, mPRE1-IL5 (-79 to -90) contains the mPRM1 at positions -87 to -89 which operates as a positive regulatory element with mutation of this motif resulting in a 64% decrease in gene activity. Gene expression was reduced by 67% when a similar mutation was introduced into the mPRM2 (-467 to -469) of mPRE2-IL5 (-459 to -470). Both elements specifically bind proteins from EL4-23 cell nuclear extracts forming constitutive DNA-protein complexes. EMSA experiments utilising mutated mPRE-IL5 oligonucleotides indicate that in both elements, the mPRMs are essential for protein binding.

Two pathways can activate the interleukin-5 gene and induce binding to the conserved lymphokine element 0

Eosinophilia is a uniquely specific phenomenon regulated by interleukin-5 (IL-5), suggesting specific control for IL-5 gene expression. Using a transient-transfection reporter assay and DNA mobility-shift experiments in EL4 mouse lymphoma cells, reporter expression and binding of transcription factors to the conserved lymphokine element 0 (CLE0) in the mouse (mIL-5) promoter was investigated. Activation of the IL-5 promoter required costimulation of T cells with phorbol ester (phorbol 12-myristate 13-acetate [PMA]) and cyclic adenosine 3',5'-monophosphate (cAMP), but was blocked by the immunosuppressive drug, cyclosporin A (CsA). Binding to CLE0 was induced under conditions optimal for IL-5 transcription but was not blocked by CsA. CD28-induced signals could partly substitute for cAMP. However, the effects of cAMP, but not of CD28, were sensitive to the cAMP-dependent protein kinase inhibitor, H89, suggesting that CD28 does not involve a cAMP mechanism. It therefore appears that IL-5 expression can be induced by at least two distinct stimulatory pathways. Although CLE0 contains sequences similar to AP-1 and NF-AT, only the AP-1 moiety of the CLE0 element could be demonstrated to have inducible binding. Experiments with antisera to the AP-1 family of transcription factors indicated that c-fos and JunB bind to the IL-5 CLE0 in activated lymphoma cells. The role of the NF-AT-like element was less clear. A constitutively expressed protein showed a weak band that was inhibited by mIL-2 NF-AT competitor sequences. However, this protein did not react with an anti-NF-ATp antiserum. On the other hand, transcription was partially inhibited by an oligonucleotide containing the intact NF-AT-like element from CLE0, suggesting that the element is important for optimal transcription, but the nature of the protein binding to it remains unknown. The fact that these factors are induced in a subclone of EL4 that does not express IL-5 and bind to a number of other cytokine gene promoters suggests that although binding to CLE0 appears to be necessary for IL-5 transcription, other factors must control the specific expression of the gene.

[Strain-gauge plethysmographic measurement of the systemic bioavailability of oral nitroglycerin in liver cirrhosis]

7 cirrhotic (M = 3, F = 4, mean age 55, range 35-74) and 7 healthy subjects (M = 6, F = 1, mean age 24, range 23-40) were studied. 2.5mg% nitroglycerin were administered per os. This drug is quite completely metabolized in its first pass through the liver (first pass effect). Peripheric vascular effect of nitroglycerin was evaluated by venous occlusion strain-gauge plethysmography, ECG-coupled (Rest Flow measurement RF, in ml/min/100 ml). No statistically significant differences were found between pre-drug RF in the two groups and between pre and post-drug measurements in healthy subjects. Post-drug RF decreased in cirrhotic subjects when compared either to pre-drug values or to post-drug values in normal subjects (statistically significant after the third minute, p ranging less than 0.05 and less than 0.001). The different peripheric vascular effect found in the two groups was considered as a consequence of the increased drug bioavailability in cirrhotics, caused by portosystemic shunts.