CT myelography by intrathecal injection of contrast medium though percutaneous administration route visualizes compressed cervical spinal cord in a mouse.

BACKGROUND: Chronic compressive myelopathy (CCM) is a major cause of spinal cord disorders in the elderly, in which the spinal cord is compressed by bony or soft tissue structures. Although computed tomography myelography (CTM) has been clinically used for the diagnosis of CCM, a method of CTM in rodents remains to be developed. NEW METHOD: A 50 µl Hamilton syringe attached to a disposable needle was percutaneously inserted into the subarachnoid space (cisterna magna) between the occipital bone and C1 lamina in an anesthetized adult mouse, followed by the injection of contrast medium and CT imaging. RESULTS: CTM clearly visualized the shape of the spinal cord of intact mice and tiptoe-walking Yoshimura (Twy) mice without any health issues. COMPARISON WITH EXISTING METHOD(S): Unlike histology, the current method functions in live mice, directly depicts the compressed spinal cord, and provides clinically related image information. Furthermore, the intrathecal administration of contrast medium through the percutaneous route makes CTM less invasive and takes less time than a conventional intrathecal injection method. CONCLUSIONS: The CTM method used in the present study enables clear visualization of the shape of the dural sac and spinal cord and is useful when conducting experiments on CCM and other spinal diseases in rodents.

Unveiling the adverse events of Nusinersen in spinal muscular atrophy management based on FAERS database.

This study aims to collect and analyze adverse event (AE) reports related to Nusinersen from the FAERS database. The study employed a combination of signal quantification techniques, including the Reporting Odds Ratio (ROR), Proportional Reporting Ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), and Multi-item Gamma Poisson Shrinker (MGPS), to enhance the accuracy of signal detection and reduce the risk of false positives or negatives. Between the first quarter of 2017 and the third quarter of 2023, the FAERS database collected a total of 11,485,105 drug AE reports, of which 5772 were related to Nusinersen. Through signal mining analysis, 218 preferred term (PT) signals involving 27 system organ classes (SOCs) were identified. The study discovered AEs related to metabolism and nutrition disorders, psychiatric disorders, and cardiac disorders SOCs, which were not mentioned in the product information. Additionally, complications directly related to the intrathecal administration of Nusinersen, such as increased CSF pressure, positive CSF red blood cell count, and AEs related to the method of drug use, such as neuromuscular scoliosis and cerebrospinal fluid reservoir placement, were highlighted. Notably, AEs related to renal function abnormalities, such as abnormal Urine protein/creatinine ratio and protein urine presence, showed higher frequency and signal strength. The findings of this study emphasize the importance of comprehensive safety monitoring in the clinical application of Nusinersen. These results are significant for guiding future clinical practices, improving disease management strategies, and developing safer treatment protocols.

Lumbar Intrathecal Injection in Adult and Neonatal Mice.

This article describes a step-by-step process of lumbar intrathecal injection of Evans blue dye and AAV9-EGFP in adult (2-month-old) and neonatal (postnatal day 10) mice. Intrathecal injection is a clinically translatable technique that has already been extensively applied in humans. In mice, intrathecal injection is considered a challenging procedure that requires a trained and experienced researcher. For both adult and neonatal mice, lumbar intrathecal injection is directed into the L5-L6 intervertebral space. Intrathecally injected material enters the cerebrospinal fluid (CSF) within the intrathecal space from where it can directly access the central nervous system (CNS) parenchyma. Simultaneously, intrathecally injected material exits the CSF with pressure gradient and enters the endoneurial fluid and ultimately the peripheral nerves. While in the CSF, the injectable material also enters the bloodstream and systemic circulation through the arachnoid villi. A successful lumbar intrathecal injection results in adequate biodistribution of the injectable material in the CNS, PNS, and peripheral organs. When correctly applied, this technique is considered as minimally invasive and non-disruptive and can be used for the lumbar delivery of any solute. © 2024 Wiley Periodicals LLC. Basic Protocol 1: C57BL/6 adult and P10 mice lumbar intrathecal injection Basic Protocol 2: Tissue collection and preparation for evaluating Evans blue dye diffusion Basic Protocol 3: Tissue collection and preparation for immunohistochemistry staining Basic Protocol 4: Tissue collection and vector genome copy number analysis.

Cdk5 inhibition in the SOD1G93A transgenic mouse model of amyotrophic lateral sclerosis suppresses neurodegeneration and extends survival.

Deregulated cyclin-dependent kinase 5 (Cdk5) activity closely correlates with hyperphosphorylated tau, a common pathology found in neurodegenerative diseases. Previous postmortem studies had revealed increased Cdk5 immunoreactivity in amyotrophic lateral sclerosis (ALS); hence, we investigated the effects of Cdk5 inhibition on ALS model mice and neurons in this study. For the in vitro study, motor neuron cell lines with wild-type superoxide dismutase 1 (SOD1) or SOD1G93A and primary neuronal cultures from SOD1G93A transgenic (TG) mice or non-TG mice were compared for the expression of proteins involved in tau pathology, neuroinflammation, apoptosis, and neuritic outgrowth by applying Cdk5-small interfering RNA or Cdk5-short hairpin RNA (shRNA). For the in vivo study, SOD1G93A mice and non-TG mice were intrathecally injected with adeno-associated virus 9 (AAV9)-scramble (SCR)-shRNA or AAV9-Cdk5-shRNA at the age of 5 weeks. Weight and motor function were measured three times per week from 60 days of age, longevity was evaluated, and the tissues were collected from 90-day-old or 120-day-old mice. Neurons with SOD1G93A showed increased phosphorylated tau, attenuated neuritic growth, mislocalization of SOD1, and enhanced neuroinflammation and apoptosis, all of which were reversed by Cdk5 inhibition. Weights did not show significant differences among non-TG and SOD1G93A mice with or without Cdk5 silencing. SOD1G93A mice treated with AAV9-Cdk5-shRNA showed significantly delayed disease onset, delayed rotarod failure, and prolonged survival compared with those treated with AAV9-SCR-shRNA. The brain and spinal cord of SOD1G93A mice intrathecally injected with AAV9-Cdk5-shRNA exhibited suppressed tau pathology, neuroinflammation, apoptosis, and an increased number of motor neurons compared to those of SOD1G93A mice injected with AAV9-SCR-shRNA. Cdk5 inhibition could be an important mechanism in the development of a new therapeutic strategy for ALS.

In vivo selection in non-human primates identifies AAV capsids for on-target CSF delivery to spinal cord.

Systemic administration of adeno-associated virus (AAV) vectors for spinal cord gene therapy has challenges including toxicity at high doses and pre-existing immunity that reduces efficacy. Intrathecal (IT) delivery of AAV vectors into cerebral spinal fluid can avoid many issues, although distribution of the vector throughout the spinal cord is limited, and vector entry to the periphery sometimes initiates hepatotoxicity. Here we performed biopanning in non-human primates (NHPs) with an IT injected AAV9 peptide display library. We identified top candidates by sequencing inserts of AAV DNA isolated from whole tissue, nuclei, or nuclei from transgene-expressing cells. These barcoded candidates were pooled with AAV9 and compared for biodistribution and transgene expression in spinal cord and liver of IT injected NHPs. Most candidates displayed increased retention in spinal cord compared with AAV9. Greater spread from the lumbar to the thoracic and cervical regions was observed for several capsids. Furthermore, several capsids displayed decreased biodistribution to the liver compared with AAV9, providing a high on-target/low off-target biodistribution. Finally, we tested top candidates in human spinal cord organoids and found them to outperform AAV9 in efficiency of transgene expression in neurons and astrocytes. These capsids have potential to serve as leading-edge delivery vehicles for spinal cord-directed gene therapies.

Efficacy and safety of intrathecal dexamethasone combined with isoniazid in the treatment of tuberculous meningitis: a meta-analysis.

BACKGROUND: The treatment regimen for tuberculous meningitis (TBM) remains unclear and requires optimization. There are some reports on successful adjunct intrathecal dexamethasone and isoniazid (IDI) treatment strategies for TBM, however, there is equivocal evidence on their efficacy and safety. METHODS: A comprehensive search of English and Chinese databases was conducted from inception to February 2024. A meta-analysis was performed on randomized controlled trials (RCTs) estimating the effects of adjunct IDI on conventional anti-TB (C anti-TB) treatments or C anti-TB alone. Efficacy, adverse reaction rate, cerebrospinal fluid (CSF) leukocytes, and CSF protein were used as primary outcome indicators. CSF glucose, CSF chlorides, CSF pressure, recovery time for laboratory indicators and recovery time for clinical symptoms were used as secondary outcome indicators. RESULTS: A total of 17 studies involving 1360 (IDI group vs. C anti-TB group: 392 vs. 372; higher-dose IDI group vs. lower-dose IDI group: 319 vs. 277) patients were included in our analysis. Efficacy was significantly higher (RR 1.3, 95% CI 1.2-1.4, P < 0.001) and adverse reaction rate was significantly lower in the IDI groups (RR 0.59, 95% CI 0.37-0.92, P = 0.021). Furthermore, CSF leukocytes (WMD - 29.33, 95% CI [- 40.64 to-18.02], P < 0.001) and CSF protein (WMD - 0.79, 95%CI [-0.96 to-0.61], P < 0.001) were significantly lower in the IDI groups. Recovery time indicators were all shorter in the IDI groups, fever (SMD - 2.45, 95% CI [-3.55 to-1.35], P < 0.001), coma (SMD-3.75, 95% CI [-4.33 to-3.17], P < 0.001), and headache (SMD  - 3.06, 95% CI [- 4.05 to-2.07], P < 0.001), respectively. Higher-dose IDI was more effective than lower-dose IDI (RR 1.23, 95% CI 1.14-1.33, P < 0.001), with no significant difference in adverse reaction rate between the two (RR 0.82, 95%CI 0.43-1.56, P = 0.544). CONCLUSION: Adjunct IDI with C anti-TB can enhance therapeutic outcomes and reduce adverse reaction rate in adult TBM patients, with higher-dose IDI showing superior efficacy. These findings highlight the potential of IDI as an adjunctive therapy in TBM management. However, more high-quality RCTs from more regions should be conducted to support our results. TRIAL REGISTRATION: Retrospectively registered in PROSPERO  https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023388860 .

Case report: Cerebrospinal fluid neutrophilic pleocytosis upon intrathecal triamcinolone injection.

Intrathecal corticosteroids, initially employed in the 1950s, faced declining use due to complications like arachnoiditis and aseptic meningitis. Triamcinolone, which is nowadays used as intrathecally applied glucocorticoid formulation, has been shown to beneficially influence spasticity without demonstrable influence on disease activity or progression. We here present the case of a patient with recurrent episodes of aseptic cerebrospinal fluid (CSF) neutrophilic pleocytosis over a year following intrathecal triamcinolone treatment. CSF analyses revealed a post-injection CSF cytokine profile resembling cytokine release reaction rather than drug hypersensitivity. This case thus highlights a potential side effect of intrathecal triamcinolone injection with yet unclear clinical relevance, underscores the need for further assessment of clinical benefits of intrathecal triamcinolone, and emphasizes potential short and long-term side effects associated with extended intrathecal triamcinolone use.

Intrathecal Baclofen Injection Efficacy for Spasticity Management in Patients With Stroke: A Meta-Analysis.

Although intrathecal baclofen injections have been used for spasticity management regarding stroke, spinal cord injury, and central nervous system diseases, their relative efficacy is controversial. This systematic review scoured 3 multinational electronic databases (Cochrane Library, MEDLINE, and Embase) to isolate relevant studies. We analyzed non-randomized studies and randomized control trials (RCTs) with direct comparisons against other spasticity management interventions for adult stroke patients. Risk of Bias (RoB) and the Risk of Bias Assessment tool for Non-randomized Studies evaluations were implemented with Cochrane's RoB tool. Meta-analysis was performed with Revman 5.4, and evidence validity was assessed with the Grading of Recommendations, Assessment, Development, and Evaluations method. Lastly, the intrathecal baclofen injection meta-analysis included 2 RCTs and 7 non-RCTs for assessing spasticity and 4 non-RCTs to measure gait velocity. Based on this data, intrathecal baclofen injection significantly impacted spasticity and gait speed. Thus, intrathecal baclofen injection can potentially treat severe spasticity unresponsive to conventional spasticity therapy. Furthermore, clinicians must consider individual patient characteristics and conditions when contemplating intrathecal baclofen injection for spasticity intervention.

Human brain clearance imaging: Pathways taken by magnetic resonance imaging contrast agents after administration in cerebrospinal fluid and blood.

Over the last decade, it has become evident that cerebrospinal fluid (CSF) plays a pivotal role in brain solute clearance through perivascular pathways and interactions between the brain and meningeal lymphatic vessels. Whereas most of this fundamental knowledge was gained from rodent models, human brain clearance imaging has provided important insights into the human system and highlighted the existence of important interspecies differences. Current gold standard techniques for human brain clearance imaging involve the injection of gadolinium-based contrast agents and monitoring their distribution and clearance over a period from a few hours up to 2 days. With both intrathecal and intravenous injections being used, which each have their own specific routes of distribution and thus clearance of contrast agent, a clear understanding of the kinetics associated with both approaches, and especially the differences between them, is needed to properly interpret the results. Because it is known that intrathecally injected contrast agent reaches the blood, albeit in small concentrations, and that similarly some of the intravenously injected agent can be detected in CSF, both pathways are connected and will, in theory, reach the same compartments. However, because of clear differences in relative enhancement patterns, both injection approaches will result in varying sensitivities for assessment of different subparts of the brain clearance system. In this opinion review article, the "EU Joint Programme - Neurodegenerative Disease Research (JPND)" consortium on human brain clearance imaging provides an overview of contrast agent pharmacokinetics in vivo following intrathecal and intravenous injections and what typical concentrations and concentration-time curves should be expected. This can be the basis for optimizing and interpreting contrast-enhanced MRI for brain clearance imaging. Furthermore, this can shed light on how molecules may exchange between blood, brain, and CSF.

A Randomized Control Study to Assess the Efficacy of Intrathecal Morphine in Patients on Patient-Controlled Analgesia Pump With Morphine for Postoperative Pain Relief After Elective Laparotomy.

Introduction Laparotomy is associated with significant prolonged postoperative pain, which can cause an adverse neuroendocrine stress response. Intrathecal morphine (ITM) retains an important place in pain management after major laparotomy since it is easier to administer and has a relatively lesser possibility of failure and technical difficulty. Aim The study aims to compare the effect of the administration of ITM with intravenous (IV) morphine administered by a patient-controlled analgesia (PCA) pump on postoperative analgesia after elective laparotomy. The primary objective was to compare total morphine consumption while secondary objectives were to compare pain assessed by the visual analog scale (VAS) and adverse reactions to opioids. Methods Sixty patients who underwent elective laparotomy were enrolled in this study. Thirty patients were enrolled in the study group (ITM+PCA) where ITM (200 mcg) was administered before laparotomy and intravenous morphine was initiated with PCA postoperatively. In the control group, only intravenous morphine was given with PCA postoperatively for pain relief. Parameters in both groups were compared, where estimation of cumulative morphine dose was the primary outcome and pain as assessed by VAS and side effects of opioids were the secondary outcomes. Results Patients in the ITM (ITM+PCA) group required less morphine (6.6 ± 2.96 vs. 24.77 ± 6.79 mg of morphine, p < 0.001) compared to patients on PCA. There was no statistically significant difference in VAS score and adverse effects between both groups. Conclusion Preoperative ITM can be used as an effective and safe modality for alleviating immediate postoperative pain following laparotomy.

A reliable and cost-effective protocol for creating bilirubin cerebral palsy model in rhesus macaque.

BACKGROUND: Cerebral palsy is a severe motor disability in childhood that poses challenges for children, families, and society. Rhesus macaques are the preferred animals for cerebral palsy model, but surgical excision of motor cortex has low success rate and high cost. In this work, we created cerebral palsy rhesus macaque models by intrathecal injection of bilirubin. METHODS: The puncture point for injection was identified as the intervertebral disc space two, located below the intersection of the iliac crest line and the posterior median line. RESULTS: The models showed abnormal posture and increased muscle tension. Diffuse deposits of bilirubin were found in the basal ganglia from the magnetic resonance imaging. Pathological slides also revealed the presence of brain lesions, such as vacuole formation, contraction of neuronal nuclei, and deep staining of nuclei in the histopathological sections of the hippocampus and basal ganglia. CONCLUSION: The model's symptoms closely resemble those observed in humans with spastic cerebral palsy.

Intrathecal injection of human placental mesenchymal stem cells derived exosomes significantly improves functional recovery in spinal cord injured rats.

BACKGROUND: Spinal cord injury (SCI) due to lack of restoration of damaged neuronal cells is associated with sensorimotor impairment. This study was focused on using the human placental mesenchymal stem cells- exosome (HPMSCs- Exosomes) in an animal model of severe SCI under myelogram procedure. METHODS AND RESULTS: Intrathecal injection of exosomes was performed in the acute phase of SCI in female rats. The improved functional recovery of the animals was followed for 6 weeks in control (saline, n = 6) and HPMSCs- EXO (HPMSCs-Exosomes, n = 6) groups. Pathological changes and glial scar size were evaluated. The Immunohistochemistry (IHC) of GFAP and NF200 factors as well as the apoptosis assay was investigated in the tissue samples from the injury site. The results demonstrated that HPMSCs-exosomes can improve motor function by attenuating apoptosis of neurons at the injury site, decreasing GFAP expression and increasing NF200 in the HPMSCs-EXO group. Also, HPMSCs-exosomes by preventing the formation of cavities causes preservation of tissue in SCI rats. CONCLUSIONS: These findings demonstrate the effectiveness of HPMSC-Exosomes as a therapeutic method to improve functional recovery, reduce pathological changes associated with injury, and prevent chronicity after SCI. The neuroprotective and anti-apoptotic potential of HPMSCs- Exosomes may be a promising therapeutic approach for SCI. Another result was the importance of intrathecal injection of exosomes in the acute phase, which accelerated the healing process. Furthermore, the myelogram can be a feasible and suitable method to confirm the accuracy of intrathecal injection and examine the subarachnoid space in the laboratory animals.

Intrathecal Injection of Polymyxin B in a Child with Meningitis Caused by Carbapenem-Resistant Pseudomonas aeruginosa: A Case Report and Literature Review.

Background: Clinically, Carbapenem-resistant Pseudomonas aeruginosa (CRPA) meningitis is extremely difficult to cure and has a high mortality rate. Intrathecal injection of polymyxins B is suggested to be an effective anti-infective means to treat intracranial infection with CRPA. However, due to the potential drug toxicity of polymyxin B in children, this regimen has rarely been reported in pediatrics. Case Description: A 5-year-old male patient diagnosed with Epstein-Barr virus-induced hemophagocytic syndrome (HPS) exhibited persistent fever for over a month despite antibacterial and chemotherapy regimens. During hospitalization, the patient presented with unconsciousness, nystagmus, and myasthenia. Cerebrospinal fluid (CSF) analysis indicated elevated leukocyte counts and protein levels. Sputum and blood cultures, as well as metagenomic next-generation sequencing (mNGS) of CSF, identified CRPA. Intravenous and intrathecal polymyxin B administration resulted in temperature normalization and amelioration of consciousness disturbances and nystagmus. Subsequent CSF analysis yielded normal results, while polymyxin B treatment exhibited no nephrotoxicity or neurotoxicity. Conclusion: Intrathecal injection of polymyxin B in children with meningitis caused by CRPA is an effective treatment without remarkable adverse events.

Efficacy of Intrathecal Isoniazid and Steroid Therapy in Refractory Tuberculous Meningitis.

Tuberculous meningitis is an infectious disease with high mortality. Literature describing intrathecal therapy for tuberculous meningitis is scarce. We herein report a case of refractory tuberculous meningitis in a 52-year-old woman with underlying neuropsychiatric systemic lupus erythematosus. Despite systemic treatment with anti-tuberculosis drugs and dexamethasone, her meningeal irritation deteriorated. Intrathecal isoniazid and prednisolone administration was therefore initiated, and the symptoms of severe meningeal irritation improved along with head magnetic resonance imaging and cerebrospinal fluid findings. This case report highlights the efficacy of intrathecal isoniazid and steroid injections for refractory tuberculous meningitis, particularly in patients with severe meningeal irritation.

Intrathecal injection of methotrexate and dexamethasone for vasculitis granuloma of the fourth ventricle: a case report and literature review.

Granulomatosis with polyangiitis (GPA) is a pauci-immune small vessel vasculitis characterised by neutrophil-mediated vasculitis and granuloma. The presence of intracranial parenchymal space-occupying lesions is rarely seen in GPA patients. In this manuscript, we report a case of GPA with granuloma of the fourth ventricle accompanied by obstructive hydrocephalus. Treatment with glucocorticoids (GCs) and multiple immunosuppressants cyclophosphamide (CYC), mycophenolate mofetil (MMF), and rituximab (RTX) showed poor efficacy in this case. After removal of the granuloma by craniotomy, GPA relapsed within 3 months. Under the premise of GC and MMF treatment combined with intrathecal injection of dexamethasone (DXM) and methotrexate (MTX), the intracranial granuloma gradually shrank, and the patient's general condition was alleviated, showing that this is an effective treatment method. Key Points • To date, there are few reports of granulomatous vasculitis combined with granuloma of the fourth ventricle, and our case is the second. • In this case, multiple immunosuppressants and rituximab were ineffective treatments, and the intracranial granuloma was effectively controlled by intrathecal injection of dexamethasone (DXM) and methotrexate (MTX). • Based on this report, it can be suggested that intrathecal injection is effective in treating patients with GPA and central nervous system involvement, but large-scale sample studies are needed.

Meta-analysis of efficacy and safety of intravenous combined with intrathecal/intraventricular injection of polymyxin against intracranial infection with multidrug-resistant bacteria / 临床神经病学杂志

Objective Evaluation of the efficacy and safety of intravenous(IV)combined with intrathecal/intraventricular injection(ITH/IVT)of polymyxin against intracranial infection with multidrug-resistant bacteria.Methods The databases,including Wanfang,VIP,Chinese Biomedical Literature,Pubmed,Embase,ScienceDirect,and Cochrane Library were searched,case-control studies on IV+ITH/IVT polymyxin against intracranial infection with multidrug-resistant bacteria by January 2023 were screen.RevMan 5.4 software was used for meta-analysis.Results A total of 9 retrospective studies were included.The fatality rate in IV+ITH/IVT polymyxin group was significantly lower than that in IV group(OR =0.19,95%CI:0.11-0.35,P＜0.01).There was no significant difference in ICU hospitalization days(OR =-2.32,95%CI:-23.59-18.89,P =0.83)and adverse reaction rate(OR =0.93,95%CI:0.26-3.38,P =0.91)between IV+ITH/IVT group and IV group.Conclusion IV+ITH/IVT polymyxin in treating the intracranial infection with multidrug-resistant bacteria can significantly reduce fatality rate,and does not significantly increase adverse reactions.

Unilateral interlaminar fenestration on the convex side provides a reliable access for intrathecal administration of nusinersen in spinal muscular atrophy: a retrospective study.

BACKGROUND: As the first gene therapy for spinal muscular atrophy (SMA), nusinersen is supposed to be administrated via intrathecal injection regularly for a lifetime. However, for SMA patients with severe spinal deformities, bony fusion following posterior spinal instrumentation sets great obstacles for the application of nusinersen. Therefore, efforts have been devoted to the exploration of appropriate approach for nusinersen administration. This study aims to evaluate the safety and reliability of unilateral interlaminar fenestration on the convex side during spinal fusion surgery for intrathecal nusinersen injection in SMA. RESULTS: SMA patients receiving posterior spinal fusion and interlaminar fenestration in Peking Union Medical College Hospital from January 2020 to October 2021 were retrospectively analyzed. 13 patients were included. Of the 13 patients, 10 were classified into SMA type II and 3 into SMA type III. Distal fusion to pelvis was undertaken in 11 patients; while L5 was selected as the lowest instrumented vertebra in the other 2 patients. All patients received interlaminar fenestration on the convex side only with an area of about 15 mm × 20 mm. Fenestration at L2-L3 level was performed in 6 patients; while L3-L4 level was selected for windowing in the remaining 7 patients. 9 of the 13 patients received lumbar puncture and intrathecal nusinersen administration during the 1-year follow-up, with an accumulative total of 50 times. All injections were performed successfully under ultrasound guidance, with no one transferred to radiographic assistance. No severe complications occurred after injection. CONCLUSIONS: In SMA with severe scoliosis planning to receive posterior spinal fusion, unilateral lumbar interlaminar fenestration on the convex side provides a feasible and reliable access for intrathecal nusinersen administration after surgery.

Modified nusinersen intrathecal injection method: inclusion of a septal needle-free closed infusion connector.

Objective: Nusinersen, an extremely expensive biologic drug (around 100,000 US$ per dose) that needs to be administered intrathecally, is approved for the treatment of 5q-spinal muscular atrophy (SMA). Because of the low muscle tone of the back muscles of pediatric SMA patients, especially type 1 SMA patients, the safe, effective, and fast execution of sheath injection is needed. Therefore, a modified intrathecal injection method was developed accordingly. This paper aims to describe the applicability and safety of this modified method. Methods: The modified intrathecal injection method (MIIM) mainly includes a septal needle-free closed infusion connector between the lumbar puncture needle and the syringe, besides the procedures of routine lumbar puncture. Its applicability and safety were evaluated through clinical observation. Results: A total of 92 children with SMA have successfully received nusinersen treatment at our hospital using the modified method since 2019 without obvious adverse events related to the modified injection method. Based on the clinical feedback of operators, the advantages of the modified method include successfully injecting the total dose of nusinersen with constant injection rate and a more stable fixation of the puncture needle, as well as making the operator more relaxed. However, compared with the routine method, the procedure of the modified method has additional steps. Conclusion: The modified intrathecal injection method is an effective and safe method to inject nusinersen when weighing the pros and cons, and it may also be used for administering intrathecal injections of other expensive medicines or for patients with other strict requirements for intrathecal injection.

A type II cannabis extract and a 1:1 blend of Δ(9)-tetrahydrocannabinol and cannabidiol display distinct antinociceptive profiles and engage different endocannabinoid targets when administered into the subarachnoid space.

Introduction: Cannabis extracts are being increasingly used to mitigate chronic pain. Current guidelines for their prescription rely on Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) content as well as the ratio of these major cannabinoids present in the blend. Here we assessed whether these descriptors were representative of product effectiveness to produce a desired outcome such as analgesia. Methods: In this study, we used a rat model of diabetic neuropathy and assessed the reduction in mechanical allodynia following intrathecal injection of pure THC, pure CBD, a 1:1 mix of these compounds and a "balanced" chemotype II cannabis extract. Engagement of endocannabinoid targets by different treatments was investigated using CB1 (AM251) and CB2 (AM630) receptor antagonists as well as a TRPV1 channel blocker (capsazepine). Results: Antinociceptive responses induced by an equivalent amount of THC administered in its pure form, as a THC:CBD mix or as a "balanced" extract were distinct. Furthermore, the 1:1 THC:CBD mix and the balanced extract had not only different response profiles but their relative engagement of CB1, CB2 receptors and TRPV1 channels was distinct. Discussion: These findings indicate that antinociceptive responses and targets engaged by blended cannabinoids are composition-specific, and cannot be simply inferred from THC and CBD contents. This information may have implications in relation to the way medicinal cannabis products are prescribed.

Intrathecal dopamine and serotonin enhance motor and nociceptive blockades of lidocaine in rats.

The study examined the effect of intrathecal injection of dopamine (serotonin) and/or lidocaine. Intrathecal injections of dopamine (serotonin or epinephrine), lidocaine, or their combination were carried out in male Sprague Dawley rats. Neurobehavioral examinations (motor and nociceptive reactions) were performed before and after spinal injection. Intrathecal serotonin (1.5 µmol), dopamine (2.5 µmol), epinephrine (1:40000), and lidocaine (0.75 µmol) produced 29%, 33%, 29%, and 54% nociceptive blockade, whereas serotonin (1.5 µmol), dopamine (2.5 µmol), or epinephrine (1:40000) produced a longer duration of nociceptive blockade than lidocaine (0.75 µmol) (P < 0.05). Serotonin (1.5 µmol), dopamine (1.25 and 2.5 µmol), or epinephrine (1:40000 and 1:80000) prolonged the duration and increased the potency of spinal motor and nociceptive blockades of lidocaine (50% effective dose, ED50) (P < 0.05). The motor and nociceptive blockades caused by lidocaine (ED50) plus dopamine (2.5 µmol) or lidocaine (ED50) plus epinephrine (1:40000) were more outstanding than lidocaine (ED50) plus serotonin (0.75 µmol) (P < 0.05). Our study provides evidence that intrathecal dopamine or serotonin produces spinal nociceptive blockade dose-dependently. Dopamine and serotonin are less potent than lidocaine in inducing spinal nociceptive blockade. When mixed with lidocaine solution, dopamine or serotonin improves spinal motor and nociceptive blockades. The motor and nociceptive blockade caused by lidocaine (ED50) plus dopamine (2.5 µmol) is similar to that caused by lidocaine (ED50) plus epinephrine (1:40000).