Nerve Sheath Research Articles

Cold Atmospheric Plasma Induces Growth Arrest and Apoptosis in Neurofibromatosis Type 1-Associated Peripheral Nerve Sheath Tumor Cells.

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder resulting from mutations in the NF1 gene. Patients harboring these mutations are predisposed to a spectrum of peripheral nerve sheath tumors (PNSTs) originating from Schwann cells, of which malignant peripheral nerve sheath tumors (MPNSTs) are the deadliest, with limited treatment options. Therefore, an unmet need still exists for more effective therapies directed at these aggressive malignancies. Cold atmospheric plasma (CAP) is a reactive oxygen species (ROS) and reactive nitrogen species (RNS) generating ionized gas that has been proposed to be a potential therapeutic modality for cancer. In this study, we sought to determine the effects of CAP on NF1-associated PNSTs. Utilizing established mouse and human cell lines to interrogate the effects of CAP in both in vitro and in vivo settings, we found that NF1-associated PNSTs were highly sensitive to CAP exposure, resulting in cell death. To our knowledge, this is the first application of CAP to NF1-associated PNSTs and provides a unique opportunity to study the complex biology of NF1-associated tumors.

Superb microvascular ultrasound is a promising non-invasive diagnostic tool to assess a ventriculoperitoneal shunt system function: a feasibility study

The objective of this pilot study was to assess the reliability of superb microvascular ultrasound (SMI) for the measurement of the cerebrospinal fluid (CSF) flow within VPS systems as an indirect sign for shunt dysfunction. Asymptomatic hydrocephalus patients, with a VPS system implanted between 2017 and 2021, were prospectively enrolled in the study. Using SMI, the CSF flow within the proximal and distal catheters were analysed. Before and after pumping the shunt reservoir, intraabdominal free fluid, optical nerve sheath diameter (ONSD), and papilla diameter (PD) were evaluated and correlated with the amount of valve activation. Nineteen patients were included. A flow was detectable in 100% (N = 19) patients in the proximal and in 89.5% (N = 17) in the distal catheter. The distal catheter tip was detectable in 27.7% (N = 5) patients. Free intraabdominal fluid was initially detected in 21.4% (N = 4) patients and in 57.9% (N = 11) at the end of the examination (P = 0.049). ONSD was significantly lower after pump activation (4.4 ± 0.9 mm versus 4.1 ± 0.8 mm, P = 0.049). Both peak velocity and flow volume per second were higher in proximal compared to distal catheters (32.2 ± 45.2 versus 5.6 ± 3.7 cm/sec, P = 0.015; 16.6 ± 9.5 ml/sec versus 5.1 ± 4.0 ml/sec, P = 0.001, respectively). No correlation was found between the number of pump activations and the changes in ONSD (P = 0.975) or PD (P = 0.820). SMI appears to be a very promising non-invasive diagnostic tool to assess CSF flow within the VPS systems and therefore affirm their function. Furthermore, appearance of free intraperitoneal fluid followed by repeated compression of a shunt reservoir indicates an intact functioning shunt system.

A Rare Case of Malignant Peripheral Nerve Sheath Tumour of the Brachial Plexus with a Diagnostic Dilemma

Abstract The brachial plexus is usually involved by tumours of adjacent areas like the lungs, breast, and cervical spine. Primary tumour of the brachial plexus are rare. It constitutes less than 5% of upper extremity tumours. Still rare are malignant tumours. Once malignancy is diagnosed there should be no delay in surgery considering the aggressive nature. Here, we discuss the diagnostic dilemma in a case of a malignant peripheral nerve sheath tumour and its surgical approach. Surgical excision was challenging because of the complex anatomy, retroclavicular/infraclavicular extension and proximity tumour to adjacent vital structures.

Evaluation of optic nerve sheath diameter in patients undergoing laparoscopic surgery in the Trendelenburg position: a prospective observational study.

The Trendelenburg position and pneumoperitoneum may cause cerebral edema and increased intracranial pressure. Non-invasive measurement of the diameter of the optic nerve sheath by ultrasonography can provide early recognition of intracranial pressure. Evaluate the optic nerve sheath diameter (ONSD) changes in patients who undergo laparoscopic surgery in the Trendelenburg position and make indirect conclusions about changes in intracranial pressure. Prospective, observational. Laparoscopic surgeries. Patients aged 18-75 years who underwent laparoscopic surgery in the Trendelenburg position under general anesthesia were included in our study. The ONSD was measured four times: Immediately after tracheal intubation, in the neutral position (baseline value) (T0), 10 minutes after pneumoperitoneum and Trendelenburg position (T1), 60 minutes after pneumoperitoneum and Trendelenburg position (T2), and 10 minutes after the pneumoperitoneum is terminated and placed in the neutral position (T3). Compare ONSD measured by ultrasonography at different times of surgery. 40. Arterial carbon dioxide pressure increased with laparoscopy and Trendelenburg position in parallel with ONSD measurements and decreased again after returning to the neutral position. It was still higher than the baseline value at the T3. There was also a significant difference[a] between the measurement made at the T2 and the measurement made at T1. This difference showed that the prolongation of the Trendelenburg time was associated with an increase in ONSD. At the end of the operation it was observed that the decreased statistically significantly (T3) 10 minutes after the pneumoperitoneum was terminated and the position was corrected. However, the ONSD was still higher at the end of the operation (T3) compared to the baseline value measured at the beginning of the operation (T0). The ONSD increased in relation to Trendelenburg position and pneumoperitoneum. With these results, we think the ultrasonographic measurement of ONSD, a non-invasive method, can be used for clinical follow-up when performing laparoscopic surgery in the Trendelenburg position in cases requiring intracranial pressure monitoring. There may be variations in the measurement of ONSD, even in the measurements of the same practitioner, as in all imaging with an ultrasonography device.

Effect of systemic lidocaine infusion on optic nerve sheath diameter during laparoscopic hysterectomy: a randomized controlled study.

During laparoscopic hysterectomy (LH), the elevation of intra-abdominal and intra-thoracic pressures due to pneumoperitoneum (PP) results in an increase in intracranial pressure (ICP). The Trendelenburg position (TP) is an accentuating factor. This trial aimed to assess the effect of intravenous (IV) lidocaine infusion on optic nerve sheath diameter (ONSD), a widely accepted surrogate measure for ICP, during PP and TP. A randomized, placebo-controlled study was conducted on 66 patients scheduled for LH, equally divided into a lidocaine group and a saline group. ONSD, the primary outcome, was recorded before induction (T1), before PP initiation in the supine position (T2), five minutes (T3), 30 minutes (T4), and 60 minutes (T5) after PP and TP, and five minutes after termination of PP in the supine position (T6). Secondary outcomes included numerical rating scale (NRS) scores at arrival to the post-anesthesia care unit (PACU), 6, 12, and 24 hours after surgery, and postoperative adverse effects. ONSD at T4 and T5 was significantly lower in the lidocaine group than in the saline group (T4: 4.94±0.43 mm vs. 5.27±0.37 mm; P =0.003, T5: 5.08±0.46 vs. 5.41±0.38 mm; P =0.004). The lidocaine group had significantly lower NRS values than the saline group only at PACU arrival (median [Q1-Q3]: 5 [4-6] vs. 6 [5-6.25]; P =0.016). Fewer patients in the lidocaine group experienced postoperative headache (P =0.029). IV lidocaine during LH can attenuate the ONSD distension, decrease pain scores at PACU arrival, and reduce the incidence of postoperative headache.

Interferon-Induced Transmembrane Protein 1 (IFITM1) Is Downregulated in Neurofibromatosis Type 1-Associated Malignant Peripheral Nerve Sheath Tumors.

Neurofibromatosis type 1 (NF1), an autosomal dominant genetic disorder, is caused by mutations in the NF1 gene, which encodes the GTPase-activating protein neurofibromin. The pathogenesis of the tumor progression of benign plexiform neurofibromas (PNs) and malignant peripheral nerve sheath tumors (MPNSTs) remain unclear. Here, we found that interferon-induced transmembrane protein 1 (IFITM1) was downregulated in MPNST tissues compared to those in PN tissues from patients with NF1. Overexpression of IFITM1 in NF1-associated MPNST cells resulted in a significant decrease in Ras activation (GTP-Ras) and downstream extracellular regulatory kinase 1/2 (ERK1/2) phosphorylation, whereas downregulation of IFITM1 via treatment with small interfering RNA in normal Schwann cells had the opposite result, indicating that expression levels of IFITM1 are closely associated with tumor progression in NF1. Treatment of MPNST cells with interferon-gamma (IFN-γ) significantly augmented the expression of IFITM1, thereby leading to a decrease in Ras and ERK1/2 activation. Despite the small number of patient samples, these findings may potentially provide a new target for chemotherapy in patients with NF1-associated MPNSTs. In xenograft mice injected with MPNST cells, IFN-γ treatment successfully suppressed tumor progression with increased IFITM1 expression and decreased Ras and ERK1/2 activation in tumor tissues. Collectively, these results suggest that IFITM1 is closely involved in MPNST pathogenesis and that IFN-γ is a good candidate for the therapeutic treatment of MPNSTs in NF1.

Silent giant: A case report of retroperitoneal schwannoma

Schwann cells of the peripheral nerve sheath give birth to soft-tissue tumors known as schwannomas (neurilemmomas). Schwannomas ofthe retroperitoneum are uncommon. Diagnosis is frequently delayed in view of unspecific clinical symptoms and non-typical radiologicfindings. The preferred course of therapy is total surgical excision. The prognosis is favorable; however, further monitoring is requireddue to the possibility of recurrence and malignant change. In this case report, we describe a case of retroperitoneal schwannoma in a44-year-old male and examine the pertinent research.

Immunohistochemical Evaluation of Schlafen 11 (SLFN11) Expression in Cancer in the Search of Biomarker-Informed Treatment Targets: A Study of 127 Entities Represented by 6658 Tumors.

Schlafen 11 (SLFN11), a DNA/RNA helicase, acts as a regulator of cellular response to replicative stress and irreversibly triggers replication block and cell death. Several preclinical in vitro studies and clinical trials established that SLFN11 expression predicts outcomes in patients with advanced cancer treated with DNA-damaging chemotherapeutics and more recently with poly(ADP-ribose) polymerase inhibitors. SLFN11 expression status remains unknown in many cancer types, especially in mesenchymal tumors. This study evaluated a cohort of well characterized 3808 epithelial and 2850 mesenchymal and neuroectodermal tumors for SLFN11 expression using immunohistochemistry. Nuclear SLFN11 expression was rare in some of the most common carcinomas, for example, hepatocellular (1%), prostatic (2%), colorectal (5%), or breast (16%) cancers. In contrast, other epithelial tumors including mesotheliomas (92%), clear cell renal cell carcinomas (79%), small cell lung cancers (76%), squamous cell carcinomas of the tonsil (89%) and larynx (71%), or ovarian serous carcinomas (69%) were mostly SLFN11-positive. Compared with epithelial malignancies, SLFN11 expression was overall higher in neuroectodermal and mesenchymal tumors. Most positive entities included desmoplastic small round cell tumor (100%), Ewing sarcoma (92%), undifferentiated sarcoma (92%), solitary fibrous tumor (91%), dedifferentiated liposarcoma (89%), synovial sarcoma (86%), and malignant peripheral nerve sheath tumor (85%). Also, this study identifies tumors with potentially worse response to DNA-damaging drugs including antibody drug conjugates due to the absence of SLFN11 expression. Such entities may benefit from alternative treatments or strategies to overcome SLFN11 deficiency-related drug resistance. Our approach and results should serve as a foundation for future biomarker-associated clinical trials.

Optic Nerve Sheath Diameter on Computed Tomography Scans Reflects Elevated Intracranial Pressure in Patients with Craniosynostosis.

Assessment for elevated intracranial pressure (ICP) helps guide interventional decision-making to treat craniosynostosis. However, non-invasive techniques for measuring ICP are limited. This study assesses whether optic nerve sheath diameter (ONSD) on low-dose computed tomography (CT) scans is associated with ICP in patients with craniosynostosis. Pediatric patients treated between 2014 and 2023 with craniosynostosis, intraoperative ICP measurements by direct subdural catheterization, and spectral domain-optical coherent tomography (SD-OCT) data were included. ONSD was retrospectively assessed on pre-operative CT scans by a masked neuroradiologist and compared to measures and proxies of ICP. Among 132 patients included, median age was 6.9 years (IQR 4.7-9.5) and 41 (31.1%) had a syndromic diagnosis. Maximum ONSD (ONSDmax) was increased in patients with ICP≥15mmHg (6.1mm vs. 5.5mm, p<0.01) and ICP≥20mmHg (6.3mm vs. 5.6mm, p<0.01). Maximum (r=0.32, p<0.001), minimum (r=0.26, p=0.003), and average (r=0.29, p<0.001) ONSD correlated with direct ICP measurements. ONSD and SD-OCT measurements were also correlated (RNFLmax: r=0.21, p=0.04; RTmax: r=0.24, p=0.02). An ONSDmax threshold of 5.75mm demonstrated 65% sensitivity and 64% specificity for detecting ICP≥15mmHg on optimized receiver operating characteristic curve analysis. Multivariable logistic regression generated an algorithm incorporating ONSDmax and age to detect ICP≥20mmHg with 64% sensitivity and 80% specificity. Optic nerve sheath diameter measured in low-dose CT scans detects elevated intracranial pressure with moderate accuracy, and precision increases when patient age is taken into consideration. Given the ease of accessing CT scan data, this may be a helpful ICP proxy for clinical decision-making.

Exploration of Choroidal Thinning Located Temporal to the Fovea: A Pilot Study.

Background/Objectives: Posterior staphyloma (PS) is a hallmark of pathological myopia, corresponding to a circumscribed outpouching of the eyeball with choroidal thinning and inward scleral deformation at its edges. Its pathogenesis is still unclear, thus constituting a research priority as the prevalence of myopia is increasing worldwide. Recently, it has been suggested that the optic nerve sheaths or oblique muscles are potential promoters of PS through the traction or compression effect that they apply to the eye wall. The inferior oblique muscle (IOM) inserts 1-2 mm from the macula. The projection of its insertion is accessible using Optical Coherence Tomography (OCT). Before launching prospective studies, we sought to detect any choroidal thinning (ChT) in the temporal vicinity of the macula and to measure the distance between it and the fovea (FT-distance). Methods: This retrospective cross-sectional pilot study included 120 eyes. Using Spectralis®-OCT, the area centered by the Bruch's membrane opening-fovea axis was analyzed for ChT and FT-distance. Results: Of the 112 defined eyes, 70% (78 eyes) had ChT. Pachymetry was significantly thinner (p = 0.018) in eyes with than without ChT. The mean FT-distance was 3601.9 ± 93.6 µm. Conclusions: The location of ChT coincided with the insertion distance of the IOM, suggesting a link between them. The association between the presence of ChT and a thinner pachymetry suggests a reduced scleral resistance, as a thinner pachymetry is related to a thinner sclera. Our results suggest a link between ocular deformation and the IOM, which may be relevant for the pathogenesis of PS, warranting further investigation.

Robotic Resection of Spinal and Paraspinal Tumors.

Robotic arm surgical systems provide minimally invasive access and are commonly used in multiple surgical fields, with limited application in neurosurgery. Our institutional experience has led us to explore the benefits of a neurosurgeon trained to perform robotic surgery as part of a multidisciplinary team. The objective of this study is to evaluate the feasibility, safety, and outcomes of robotic resection for spinal nerve sheath tumors (NST). Retrospective case series of robotic-assisted intracavitary approaches and resection of NSTs including thoracic, retroperitoneal, and transperitoneal. Surgical outcomes are compared to a historical cohort of open surgical resection of NSTs. Nineteen cases presented, of which 2 were combined posterior spinal followed by robotic tumor resection. One of 19 cases was converted to an open surgery. Gross total resection was achieved in all cases. There were 2 cases of postoperative Horner's syndrome, and 1 case with an intraoperative durotomy that was repaired primarily with no postoperative sequelae. Median estimated blood loss was 50 cc (range: 5-650) and median length of stay was 1 day (range: 0-6), with 9 (47.4%) patients discharged on postoperative day 1 and 3 (15.8%) patients discharged on an outpatient basis. Compared with our previously reported institutional outcomes for open resection of 25 tumors, there was a significant increase in rates of gross total resection (100 vs 60%, P = .002) and decrease in length of stay (median 1 vs 5 days, P < .0001). Robotic resection of complex paraspinal tumors appears safe and effective including for preservation of neurological function and may reduce surgical morbidity. Integration of robotic surgical platforms holds the potential to significantly affect neurological surgery.

Normative Measurements of the Infraorbital Nerve by Magnetic Resonance Imaging in an Australia Cohort.

To report the normative dimensions of the infraorbital nerve on fat-suppressed gadolinium-enhanced MRI and correlate with patient demographics in an Australian cohort. A retrospective review of patients who underwent coronal fat-suppressed gadolinium T1-weighted MRI from September 2021 to December 2023. One hundred sixty-eight orbits were included. The maximum diameter of the infraorbital nerve and the optic nerve sheath was measured. Orbits were excluded if there was unilateral or bilateral pathology of the infraorbital nerve or optic nerve sheath, incomplete MRI sequences, poor image quality, or indiscernible infraorbital nerve on radiological examination. The mean age of participants was 58 ± 16 years, and 50% were females (n = 42). The mean normative measurements (mean ± standard deviation) on coronal T1-weighted imaging: optic nerve sheath, 5.08 ± 0.67 mm. On coronal fat-suppressed gadolinium T1-weighted imaging: infraorbital nerve, 0.89 ± 0.22mm. No significant differences were found between male or female participants in both the infraorbital nerve (p = 0.757) or optic nerve sheath (p = 0.646). There was no significant correlation between age and mean diameter of the infraorbital nerve (r = 0.077, p = 0.320) or optic nerve sheath (r = 0.075, p = 0.336). Additionally, no significant difference was identified between the mean diameter of the infraorbital nerve (p = 0.079) and optic nerve sheath (p = 0.120) across age groups. The mean infraorbital nerve to optic nerve sheath ratio was 0.18 ± 0.00. Normative dimensions of the infraorbital nerve may be used to identify enlargement in conditions such as IgG4-related ophthalmic disease and reactive lymphoid hyperplasia.

Minimally Destabilizing Corridor for Resection of Dumbbell Nerve Sheath Tumors: A Novel Surgical Technique.

Current surgical strategies for dumbbell nerve sheath tumors (DNSTs) with cord compression have primarily involved wide spinal exposures with total laminectomy and unilateral facetectomy, often leading to spinal destabilization and requiring fusion, or staged procedures separately addressing the intraspinal and extraforaminal tumor components. This study highlights technical nuances of a novel approach for DNST resection to minimize spinal destabilization and avoid fusion while facilitating safe, single-stage complete resection. A retrospective chart review was conducted on patients undergoing DNST resection. Using unilateral subperiosteal dissection, hemilaminotomy and medial facetectomy procedures are performed. The extradural tumor component is resected, followed by internal decompression of the intradural tumor. A small horizontal incision at the origin of the nerve root sleeve releases the underlying dural stricture, facilitating delivery of the remaining intradural tumor and allowing section of the nerve root of origin. Ultrasonography confirms complete tumor resection and return of cord pulsation, and excludes intradural hemorrhagic complications. The dura is reconstructed using a dural substitute bolstered with fat graft and sealant. Twelve consecutive patients undergoing this approach from 2014 to 2021 were included. Mean patient age was 53.5 years, and 58.3% were male. Nine tumors were cervical and 3 were lumbar. Five patients presented with myelopathy, 4 with radiculopathy, and 4 with axial pain. Two cases had transient intraoperative neuromonitoring signal changes. Eleven tumors were diagnosed as schwannomas and 1 as neurofibroma. All patients had complete resection of the intraspinal component; 2 had far distal extraforaminal residual. No patient has had recurrence, progression of residual, or signs of spinal instability during follow-up (median 28.5 months, range 6-66 months). This study highlights technical considerations for DNST resection, focusing the approach at the center of the tumor, with minimal bone removal and ligamentous disruption. Intraoperative ultrasound is instrumental in the safety of this approach.

The CoREST complex is a therapeutic vulnerability in malignant peripheral nerve sheath tumors.

Malignant peripheral nerve sheath tumor (MPNST) is a highly aggressive sarcoma that may be seen in patients with neurofibromatosis type 1 (NF1) or occur sporadically. While surgery is the primary treatment for localized MPNST with a 61.9% overall survival rate, metastatic disease is often fatal due to resistance to systemic therapies which underscores the urgent need for effective treatments. MPNSTs frequently harbor inactivating driver mutations in the PRC2 epigenetic repressor complex suggesting epigenetic therapies may represent a specific vulnerability in these tumors. Here, we investigate the role of the LSD1-HDAC1-CoREST (LHC) repressor complex in mediating MPNST tumor growth and progression. Our findings demonstrate that the LHC small molecule inhibitor, corin, induces apoptosis and significantly inhibits proliferation in MPNST cells. Transcriptomic analysis of corin-treated MPNST cells demonstrates specific increases in genes associated with axonogenesis and neuronal differentiation as well as altered extracellular matrix; additionally, corin treatment is shown to inhibit MPNST invasion in vitro. These results underscore the critical role of the LHC complex in facilitating MPNST growth and progression and suggest that targeting the LHC complex represents a promising therapeutic approach for this aggressive malignancy.

Non-invasive estimation of cerebrospinal fluid pressure in idiopathic intracranial hypertension: magnetic resonance imaging analysis of optic nerve and eyeball.

Invasive methods such as lumbar puncture and intraventricular catheters are commonly used to measure intracranial pressure (ICP). This study aims to develop quantitative and non-invasive techniques to measure ICP in patients with Idiopathic Intracranial Hypertension (IIH) using magnetic resonance imaging (MRI) findings. MRI data obtained from 50 patients with IIH and 30 age- and sex- matched controls were analyzed and optic nerve sheath diameter (ONSD), eyeball transverse diameter (ETD) and optic nerve diameter (OND) were measured. ONSD, ONSD/ETD and OND/ONSD indexes were calculated according to different ONSD measurement distances. Correlations of MRI findings with ICP were calculated. Sensitivity and specificity of all methods were analyzed. ONSD and ONSD/ETD index at 3mm and 10mm behind the eyeball were significantly higher (p < 0.001) and OND/ONSD index at 3mm behind the eyeball was significantly lower (p < 0.001) in the IIH group. The ONSD/ETD index at 3mm had the highest area under the curve (AUC) value (0.898) with a cut-off of 0.27mm (82% sensitivity and 91.67% specificity) for predicting high cerebrospinal fluid (CSF) pressure, followed by ONSD measurements at 3mm (AUC = 0.886) with a cut-off of 6.17mm (83% sensitivity and 86.67% specificity). The OND/ONSD index at 3mm posterior to the eyeball decreased significantly as ICP increased, and the strength of the relationship was moderate (p < 0.001; r = -0.358). ONSD and ONSD/ETD index measured on MRI sequences are potentially useful in detecting elevated ICP. The OND/ONSD index correlates with CSF pressure and these techniques may be helpful in diagnosing IIH.

Optic Nerve Amyloid Deposition Disguised as Optic Nerve Sheath Meningioma.

Localized orbital amyloidosis is a rare clinical entity. Periocular and orbital amyloid deposits are mainly located at the lacrimal apparatus, eyelid, conjunctiva, ocular adnexa, extraocular muscles, and levator palpebrae muscle. In this article, we report an unusual case of optic nerve amyloid deposition in an 82-year-old African American woman who presented with vertical diplopia. MRI revealed an enhancing mass from the optic nerve sheath, and CT showed foci of calcifications suggestive of optic nerve meningioma. However, an incisional biopsy demonstrated lymphoproliferative disease with focal optic nerve sheath amyloid deposition confirmed by histologic Congo red staining and immunohistochemistry.

Prognostic Value of Optic Nerve Sheath Diameters after Acute Ischemic Stroke According to Slice Thickness on Computed Tomography.

The optic nerve sheath diameter (ONSD) can predict intracranial pressure and outcomes in neurological disease, but it remains unclear whether a small ONSD can be accurately measured on routine CT images with a slice thickness of approximately 4-5 mm. We measured the ONSD and ONSD/eyeball transverse diameter (ETD) ratio on routine-slice (4 mm) and thin-slice (0.6-0.75 mm) brain CT images from initial scans of acute ischemic stroke (AIS) patients. ONSD-related variables, National Institutes of Health Stroke Scale (NIHSS) scores, and age were compared between good (modified Rankin Scale [mRS] ≤ 2) and poor (mRS > 2) outcomes at discharge. Among 155 patients, 38 had poor outcomes. The thin-slice ONSD was different between outcome groups (p = 0.047), while the routine-slice ONSD showed no difference. The area under the curve (AUC) values for the ONSD and ONSD/ETD were 0.58 (95% CI, 0.49-0.66) and 0.58 (95% CI, 0.50-0.66) on the routine-slice CT, and 0.60 (95% CI, 0.52-0.68) and 0.62 (95% CI, 0.54-0.69) on the thin-slice CT. The thin-slice ONSD/ETD ratio correlated with initial NIHSS scores (r = 0.225, p = 0.005). After adjusting for NIHSS scores and age, ONSD-related variables were not associated with outcomes, and adding them to a model with NIHSS scores and age did not improve performance (all p-values > 0.05). Although ONSD measurements were not an independent outcome predictor, they correlated with stroke severity, and the thin-slice ONSD provided a slightly better prognostic performance than the routine-slice ONSD.

Nursing management of intracranial hypertension in adults with severe brain injury in a neurosurgery intensive care unit: a best practice implementation project.

The nursing management of intracranial hypertension in adult patients with severe brain injury is crucial for maintaining the stability of intracranial pressure, which ultimately improves patient outcomes. This project aimed to implement evidence-based practices for the nursing management of intracranial hypertension in adult patients with severe brain injury. This evidence implementation project was conducted in a neurosurgery intensive care unit in a large tertiary hospital in Guangzhou, China. The project was guided by the JBI Evidence Implementation Framework, which is an audit and feedback model with seven stages. The Ottawa Model of Research Use was used to identify barriers and facilitators to best practices and to develop improvement strategies. Thirty-three nurses and 50 patients with severe brain injury participated in the baseline and follow-up audits. After project implementation, follow-up audits revealed significantly improved compliance with best practices compared with baseline. Nurses' awareness of best practices increased (41% to 96%); nursing assessment, monitoring, and interventions related to intracranial hypertension rose significantly (from 82%, 75%, and 59% to 98%, 84%, and 87%, respectively); and patients' optic nerve sheath diameter was notably lower (6.002±0.677 mm to 5.698±0.730 mm). The systematic integration of consistent training and education, together with the refinement of care processes and the creation of relevant tools, led to a significant improvement in awareness and adherence to best practices. Further testing of this program in more hospitals is needed. http://links.lww.com/IJEBH/A243.

Diagnostic Accuracy of Optic Nerve Sheath Diameter Using Ultrasonography for Raised Intracranial Pressure in Pediatric Patients - A Systematic Review and Meta-Analysis

PurposeDetecting increased intracranial pressure early in pediatric patients is essential, as early initiation of therapy prevents morbidity and mortality. The objective of this study was to determine the diagnostic accuracy of the ONSD measured via ultrasound for the prediction of increased intracranial pressure. MethodsFour databases, namely, PubMed, EMBASE, Scopus & CINAHL, were searched for this systematic review and meta-analysis. The study's predefined inclusion criteria considered diagnostic accuracy, cross-sectional, prospective observational, and retrospective studies with a focus on children with elevated intracranial pressure from causes such as traumatic brain injury and cerebral edema, the diagnostic accuracy of the optic nerve sheath diameter measured using ultrasound was assessed. The primary outcome measures included sensitivity, specificity. The study included invasive monitoring (EVD) and noninvasive measures as the gold standards for increased intracranial pressure. Two authors extracted and reviewed the data. Baseline data, outcome measures, and diagnostic accuracy data were extracted. ResultsTwenty-five studies with 1,591 patients and 3,143 ONSD measurements via ultrasound were analyzed. The pooled sensitivity and specificity of the ONSD measured via ultrasound for the prediction of increased intracranial pressure were 92% (86–96%) and 89% (77–96%), respectively. The pooled positive and negative likelihood ratios were 8.6 and 0.08, respectively. Conclusion and RelevanceOptic nerve ultrasonography stands out as a precise and valuable diagnostic tool applicable across diverse patient populations and clinical scenarios. We recommend routine ocular ultrasound for optic nerve sheath diameter measurement in pediatric patients to increase the accuracy of diagnosing increased intracranial pressure.

Tensile properties of glaucomatous human sclera, optic nerve, and optic nerve sheath.

We characterized the tensile behavior of sclera, optic nerve (ON), and ON sheath in eyes from donors with glaucoma, for comparison with published data without glaucoma. Twelve freshly harvested eyes were obtained from donors with history of glaucoma, of average age 86 ± 7 (standard deviation) years. Rectangular samples were taken from anterior, equatorial, posterior, and peripapillary sclera, and ON sheath, while ON was in native form and measured using calipers. Under physiological temperature and humidity, tissues were preconditioned at 5% strain before loading at 0.1mm/s. Force-displacement data were converted into engineering stress-strain curves fit by reduced polynomial hyperelastic models and analyzed by tangent moduli at 3% and 7% strain. Data were compared with an age-matched sample of 7 published control eyes. Optic atrophy was supported by significant reduction in ON cross section to 73% of normal in glaucomatous eyes. Glaucomatous was significantly stiffer than control in equatorial and peripapillary regions (P < 0.001). However, glaucomatous ON and sheath were significantly less stiff than control, particularly at low strain (P < 0.001). Hyperelastic models were well fit to stress-strain data (R2 > 0.997). Tangent moduli had variability similar to control in most regions, but was abnormally large in peripapillary sclera. Tensile properties were varied independently among various regions of the same eyes. Glaucomatous sclera is abnormally stiff, but the ON and sheath are abnormally compliant. These abnormalities correspond to properties predicted by finite element analysis to transfer potentially pathologic stress to the vulnerable disk and lamina cribrosa region during adduction eye movement.