A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies available to promote nerve regeneration.Tacrolimus accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve surgery.The authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug exposure.Tacrolimus is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 days.Size and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible byproducts.Tacrolimus released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic delivery.Given its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

Neutrophil peptide 1 accelerates the clearance of degenerative axons during Wallerian degeneration by activating macrophages after peripheral nerve crush injury

Macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still unclear.Our preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve regeneration.However,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains unclear.This study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush injury.The functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent assay.Axonal debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian degeneration.Macrophage inflammatory factor expression in different polarization states was detected using a protein chip.The results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating M2 polarization.The axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 intervention.Neutrophil peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in vitro.Thus,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.

Vagus nerve stimulation in cerebral stroke:biological mechanisms,therapeutic modalities,clinical applications,and future directions

Stroke is a major disorder of the central nervous system that poses a serious threat to human life and quality of life.Many stro ke victims are left with long-term neurological dysfunction,which adversely affects the well-being of the individual and the broader socioeconomic impact.Currently,poststroke brain dysfunction is a major and difficult area of treatment.Vagus nerve stimulation is a Food and Drug Administration-approved exploratory treatment option for autis m,refractory depression,epilepsy,and Alzheimer’s disease.It is expected to be a novel therapeutic technique for the treatment of stroke owing to its association with multiple mechanisms such as alte ring neurotransmitters and the plasticity of central neuro ns.In animal models of acute ischemic stroke,vagus nerve stimulation has been shown to reduce infarct size,reduce post-stroke neurological damage,and improve learning and memory capacity in rats with stroke by reducing the inflammatory response,regulating bloodbrain barrier permeability,and promoting angiogenesis and neurogenesis.At present,vagus nerve stimulation includes both invasive and non-invasive vagus nerve stimulation.Clinical studies have found that invasive vagus nerve stimulation combined with rehabilitation therapy is effective in im proving upper limb motor and cognitive abilities in stroke patients.Further clinical studies have shown that non-invasive vagus nerve stimulation,including ear/ce rvical vagus nerve stimulation,can stimulate vagal projections to the central nervous system similarly to invasive vagus nerve stimulation and can have the same effect.In this paper,we first describe the multiple effects of vagus nerve stimulation in stroke,and then discuss in depth its neuroprotective mechanisms in ischemic stroke.We go on to outline the res ults of the current major clinical applications of invasive and non-invasive vagus nerve stimulation.Finally,we provide a more comprehensive evaluation of the advantages and disadvantages of different types of vagus nerve stimulation in the treatment of cerebral ischemia and provide an outlook on the developmental trends.We believe that vagus nerve stimulation,as an effective treatment for stroke,will be widely used in clinical practice to promote the recovery of stroke patients and reduce the incidence of disability.

Chemokine platelet factor 4 accelerates peripheral nerve regeneration by regulating Schwann cell activation and axon elongation

Schwann cells in peripheral nerves react to traumatic nerve injury by attempting to grow and regenerate.Howeve r,it is unclear what factors play a role in this process.In this study,we searched a GEO database and found that expression of platelet factor 4 was markedly up-regulated after sciatic nerve injury.Platelet factor is an important molecule in cell apoptosis,diffe rentiation,survival,and proliferation.Further,polymerase chain reaction and immunohistochemical staining confirmed the change in platelet factor 4 in the sciatic nerve at different time points after injury.Enzyme-linked immunosorbent assay confirmed that platelet factor 4 was secreted by Schwann cells.We also found that silencing platelet factor 4 decreased the proliferation and migration of primary cultured Schwann cells,while exogenously applied platelet factor 4 stimulated Schwann cell prolife ration and migration and neuronal axon growth.Furthermore,knocking out platelet factor 4 inhibited the prolife ration of Schwann cells in injured rat sciatic nerve.These findings suggest that Schwann cell-secreted platelet factor 4 may facilitate peripheral nerve repair and regeneration by regulating Schwann cell activation and axon growth.Thus,platelet factor 4 may be a potential therapeutic target for traumatic peripheral nerve injury.

Role of transforming growth factor-βin peripheral nerve regeneration

Injuries caused by trauma and neurodegenerative diseases can damage the peripheral nervous system and cause functional deficits.Unlike in the central nervous system,damaged axons in peripheral nerves can be induced to regenerate in response to intrinsic cues after reprogramming or in a growth-promoting microenvironment created by Schwann cells.However,axon regeneration and repair do not automatically result in the restoration of function,which is the ultimate therapeutic goal but also a major clinical challenge.Transforming growth factor(TGF)is a multifunctional cytokine that regulates various biological processes including tissue repair,embryo development,and cell growth and differentiation.There is accumulating evidence that TGF-βfamily proteins participate in peripheral nerve repair through various factors and signaling pathways by regulating the growth and transformation of Schwann cells;recruiting specific immune cells;controlling the permeability of the blood-nerve barrier,thereby stimulating axon growth;and inhibiting remyelination of regenerated axons.TGF-βhas been applied to the treatment of peripheral nerve injury in animal models.In this context,we review the functions of TGF-βin peripheral nerve regeneration and potential clinical applications.

Harnessing endothelial cells and vascularization strategies for nerve regeneration

Peripheral nerves are essential components of the human body’s communication system,transmitting signals between the central nervous system and various body parts.Damage resulting from trauma or disease can result in debilitating sensory and motor deficits.Nerve injuries,particularly those resulting in significant gaps in the nerve tissue,pose a formidable challenge for clinicians and researchers.Despite their limitations,including limited availability and donor site morbidity,nerve autografts remain the clinical gold standard for treating nerve injuries.

Effects of exosomes from mesenchymal stem cells on functional recovery of a patient with total radial nerve injury: A pilot study

BACKGROUND Peripheral nerve injury can result in significant clinical complications that have uncertain prognoses.Currently,there is a lack of effective pharmacological interventions for nerve damage,despite the existence of several small compounds,Despite the objective of achieving full functional restoration by surgical intervention,the persistent challenge of inadequate functional recovery remains a significant concern in the context of peripheral nerve injuries.AIM To examine the impact of exosomes on the process of functional recovery following a complete radial nerve damage.METHODS A male individual,aged 24,who is right-hand dominant and an immigrant,arrived with an injury caused by a knife assault.The cut is located on the left arm,specifically below the elbow.The neurological examination and electrodiagnostic testing reveal evidence of left radial nerve damage.The sural autograft was utilized for repair,followed by the application of 1 mL of mesenchymal stem cell-derived exosome,comprising 5 billion microvesicles.This exosome was split into four equal volumes of 0.25 mL each and delivered microsurgically to both the proximal and distal stumps using the subepineural pathway.The patient was subjected to a period of 180 d during which they had neurological examination and electrodiagnostic testing.RESULTS The duration of the patient’s follow-up period was 180 d.An increasing Tinel’s sign and sensory-motor recovery were detected even at the 10th wk following nerve grafting.Upon the conclusion of the 6-mo post-treatment period,an evaluation was conducted to measure the extent of improvement in motor and sensory functions of the nerve.This assessment was based on the British Medical Research Council scale and the Mackinnon-Dellon scale.The results indicated that the level of improvement in motor function was classified as M5,denoting an excellent outcome.Additionally,the level of improvement in sensory function was classified as S3+,indicating a good outcome.It is noteworthy that these assessments were conducted in the absence of physical therapy.At the 10th wk post-injury,despite the persistence of substantial axonal damage,the nerve exhibited indications of nerve re-innervation as evidenced by control electromyography(EMG).In contrast to the preceding.EMG analysis revealed a significant electrophysiological enhancement in the EMG conducted at the 6th-mo follow-up,indicating ongoing regeneration.CONCLUSION Enhanced comprehension of the neurobiological ramifications associated with peripheral nerve damage,as well as the experimental and therapy approaches delineated in this investigation,holds the potential to catalyze future clinical progress.

Human umbilical cord mesenchymal stem cell-derived exosomes loaded into a composite conduit promote functional recovery after peripheral nerve injury in rats

Complete transverse injury of peripheral nerves is challenging to treat.Exosomes secreted by human umbilical cord mesenchymal stem cells are considered to play an important role in intercellular communication and regulate tissue regeneration.In previous studies,a collagen/hyaluronic acid sponge was shown to provide a suitable regeneration environment for Schwann cell proliferation and to promote axonal regeneration.This three-dimensional(3D)composite conduit contains a collagen/hyaluronic acid inner sponge enclosed in an electrospun hollow poly(lactic-co-glycolic acid)tube.However,whether there is a synergy between the 3D composite conduit and exosomes in the repair of peripheral nerve injury remains unknown.In this study,we tested a comprehensive strategy for repairing long-gap(10 mm)peripheral nerve injury that combined the 3D composite conduit with human umbilical cord mesenchymal stem cell-derived exosomes.Repair effectiveness was evaluated by sciatic functional index,sciatic nerve compound muscle action potential recording,recovery of muscle mass,measuring the cross-sectional area of the muscle fiber,Masson trichrome staining,and transmission electron microscopy of the regenerated nerve in rats.The results showed that transplantation of the 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes promoted peripheral nerve regeneration and restoration of motor function,similar to autograft transplantation.More CD31-positive endothelial cells were observed in the regenerated nerve after transplantation of the loaded conduit than after transplantation of the conduit without exosomes,which may have contributed to the observed increase in axon regeneration and distal nerve reconnection.Therefore,the use of a 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes represents a promising cell-free therapeutic option for the treatment of peripheral nerve injury.

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status.Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed.Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future.

Effect of a cervical collar on optic nerve sheath diameter in trauma patients

BACKGROUND:As advocated in advanced trauma life support and prehospital trauma life support protocols,cervical immobilization is applied until cervical spine injury is excluded.This study aimed to show the difference in optic nerve sheath diameter(ONSD)between patients with and without a cervical collar using computed tomography(CT).METHODS:This was a single-center,retrospective study examining trauma patients who presented to the emergency department between January 1,2021,and December 31,2021.The ONSD on brain CT of the trauma patients was measured and analyzed to determine whether there was a difference between the ONSD with and without the cervical collar.RESULTS:The study population consisted of 169 patients.On CT imaging of patients with(n=66)and without(n=103)cervical collars,the mean ONSD in the axial plane were 5.43±0.50 mm and 5.04±0.46 mm respectively for the right eye and 5.50±0.52 mm and 5.11±0.46 mm respectively for the left eye.The results revealed an association between the presence of a cervical collar and the mean ONSD,which was statistically significant(P<0.001)for both the right and left eyes.CONCLUSION:A cervical collar may be associated with increased ONSD.The effect of this increase in the ONSD on clinical outcomes needs to be investigated,and the actual need for cervical collar in the emergency department should be evaluated on a case-by-case basis.

Chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor for neurotrophic keratopathy

Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.

Application Research of PETD Combined with MRI Nerve Root Water Imaging in the Minimally Invasive Treatment of LDH

Objective: This study aims to evaluate the safety and efficacy of PETD combined with nerve root water imaging of MRI for the treatment of lumbar disc herniation. Methods: A retrospective review was performed on 62 patients with lumbar disc herniation from March 2019 to March 2021. The study included an experimental group of 30 patients and a control group of 32 patients. The experimental group underwent PETD combined with nerve root water imaging of MRI, while the control group received traditional PETD treatment. The visual analogue scoring method (VAS score), and JOA lumbar spine function score before and after surgery were compared between the two groups, and efficacy was assessed and compared using the MacNab score. Results: The mean operation time was significantly reduced in the experimental group (56.43 &#177;10.40 minutes) compared to the control group (65.69 &#177;14.12 minutes). The VAS score was compared between the two groups with preoperative (p = 0.624), one month after surgery (p = 0.325), three months after surgery (p = 0.676), one year after surgery (p = 0.341);The JOA score was compared between the two groups with preoperative (p = 0.961), one month after the surgery (p = 0.266), three months after surgery (p = 0.185), one year after surgery (p = 0.870), they were no significant statistical difference;The efficacy evaluation of the last follow-up Macnab showed that all the 30 patients in the experimental group were excellent, 31 of 32 patients in the control group were excellent, 1 case was good;There was no statistical difference in the comparison between the two groups (p > 0.05). Conclusion: The study concludes that the combined approach of PETD with nerve root water imaging of MRI is a safe, effective, and more efficient alternative to conventional PETD for treating lumbar disc herniation.

Runx2 regulates peripheral nerve regeneration to promote Schwann cell migration and re-myelination

Runx2 is a major regulator of osteoblast differentiation and function;however,the role of Runx2 in peripheral nerve repair is unclea r.Here,we analyzed Runx2expression following injury and found that it was specifically up-regulated in Schwann cells.Furthermore,using Schwann cell-specific Runx2 knocko ut mice,we studied peripheral nerve development and regeneration and found that multiple steps in the regeneration process following sciatic nerve injury were Runx2-dependent.Changes observed in Runx2 knoc kout mice include increased prolife ration of Schwann cells,impaired Schwann cell migration and axonal regrowth,reduced re-myelination of axo ns,and a block in macrophage clearance in the late stage of regeneration.Taken together,our findings indicate that Runx2 is a key regulator of Schwann cell plasticity,and therefore peripheral nerve repair.Thus,our study shows that Runx2 plays a major role in Schwann cell migration,re-myelination,and peripheral nerve functional recovery following injury.

Mesenchymal stem cells for repairing glaucomatous optic nerve

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and axons.Currently,there is no effective method to address the cause of RGCs degeneration.However,studies on neuroprotective strategies for optic neuropathy have increased in recent years.Cell replacement and neuroprotection are major strategies for treating glaucoma and optic neuropathy.Regenerative medicine research into the repair of optic nerve damage using stem cells has Received considerable attention.Stem cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine effects.This article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

The Construction of Integrated Nursing Model Prevention of Oxaliplatin Chemotherapy-Induced Peripheral Nerve Injury

Objective: To investigate the effect of the integrated nursing model in the prevention of chemotherapy-induced peripheral injury. Methods: A total of 60 tumor patients receiving oxaliplatin for 1 - 6 cycles of chemotherapy from January to September 2023 were selected. 30 patients were selected from January to March and divided into the control group, and 30 patients were selected from July to 9 as the experimental group. The control group received conventional chemotherapy nursing, while the experimental group received integrated nursing. Anxiety, peripheral nerve toxicity stage and quality of life score were compared between the two groups before and after intervention. Results: After intervention, the scores of the self-rating Anxiety Scale (SAS) and the total scores of the oxaliplatin Levi specific sensory neurotoxicity scale in the experimental group were significantly lower than those in the control group, and the differences were statistically significant (P< 0.05);The Quality of Life Scale (FACT-G) score of cancer patients was higher than that of control group, and the difference was statistically significant (P< 0.05). Conclusion: The integrated nursing model can effectively reduce the anxiety of patients, reduce the incidence of peripheral nerve injury and improve the quality of life of patients.

Millimetric devices for nerve stimulation:a promising path towards miniaturization

Nerve stimulation is a rapidly developing field,demonstrating positive outcomes across several conditions.Despite potential benefits,current nerve stimulation devices are large,complicated,and are powered via implanted pulse generators.These facto rs necessitate invasive surgical implantation and limit potential applications.Reducing nerve stimulation devices to millimetric sizes would make these interventions less invasive and facilitate broader therapeutic applications.However,device miniaturization presents a serious engineering challenge.This review presents significant advancements from several groups that have overcome this challenge and developed millimetricsized nerve stimulation devices.These are based on antennas,mini-coils,magneto-electric and optoelectronic materials,or receive ultrasound power.We highlight key design elements,findings from pilot studies,and present several considerations for future applications of these devices.

Epithelioid malignant peripheral nerve sheath tumor of the bladder and concomitant urothelial carcinoma: A case report

BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwannomas of pelvic autonomic nerve plexuses,and unlike the conventional malignant peripheral nerve sheath tumor(MPNST),are not associated with neurofibromatosis.The tumor has dis-tinctive morphological,immunohistochemical and molecular features.Addi-tionally,it tends to be more aggressive and have a higher mortality.This is the first case that presents with a synchronous urothelial carcinoma of the bladder and the epithelioid variant of MPNST in the literature.It’s also the second re-ported case of EMPNST originating from the bladder wall.CASE SUMMARY In this case report,we present the detailed clinical course of a 71-year-old patient with EMPNST of the bladder alongside a literature review.CONCLUSION During the management of EMPNST cases,offering aggressive treatment moda-lities to the patient,such as radical cystectomy,is appropriate for the best chance to contain the disease,regardless of the tumor stage and the extent of local disease at initial diagnosis.

Mesenchymal stem cells’“garbage bags”at work:Treating radial nerve injury with mesenchymal stem cell-derived exosomes

Unlike central nervous system injuries,peripheral nerve injuries(PNIs)are often characterized by more or less successful axonal regeneration.However,structural and functional recovery is a senile process involving multifaceted cellular and molecular processes.The contemporary treatment options are limited,with surgical intervention as the gold-standard method;however,each treatment option has its associated limitations,especially when the injury is severe with a large gap.Recent advancements in cell-based therapy and cell-free therapy approaches using stem cell-derived soluble and insoluble components of the cell secretome are fast-emerging therapeutic approaches to treating acute and chronic PNI.The recent pilot study is a leap forward in the field,which is expected to pave the way for more enormous,systematic,and well-designed clinical trials to assess the therapeutic efficacy of mesenchymal stem cell-derived exosomes as a bio-drug either alone or as part of a combinatorial approach,in an attempt synergize the best of novel treatment approaches to address the complexity of the neural repair and regeneration.

Concomitant treatment of ureteral calculi and ipsilateral pelvic sciatic nerve schwannoma with transperitoneal laparoscopic approach: A case report

BACKGROUND Schwannomas are rare peripheral neural myelin sheath tumors that originate from Schwann cells.Of the different types of schwannomas,pelvic sciatic nerve schwannoma is extremely rare.Definite preoperative diagnosis of pelvic schwannomas is difficult,and surgical resection is the gold standard for its definite diagnosis and treatment.CASE SUMMARY We present a case of pelvic schwannoma arising from the sciatic nerve that was detected in a 40-year-old man who underwent computed tomography for intermittent right lower back pain caused exclusively by a right ureteral calculus.Subsequently,successful transperitoneal laparoscopic surgery was performed for the intact removal of the stone and en bloc resection of the schwannoma.The total operative time was 125 min,and the estimated blood loss was inconspicuous.The surgical procedure was uneventful.The patient was discharged on postoperative day 5 with the simultaneous removal of the urinary catheter.However,the patient presented with motor and sensory disorders of the right lower limb,caused by partial damage to the right sciatic nerve.No tumor recurrence was observed at the postoperative appointment.CONCLUSION Histopathological examination of the specimen confirmed the diagnosis of a schwannoma.Thus,laparoscopic surgery is safe and feasible for concomitant extirpation of pelvic schwannomas and other pelvic and abdominal diseases that require surgical treatment.

Repeatability,interocular correlation and agreement of optic nerve head vessel density in healthy eyes:a sweptsource optical coherence tomographic angiography study

AIM:To assess the repeatability,interocular correlation,and agreement of quantitative swept-source optical coherence tomography angiography(OCTA)optic nerve head(ONH)parameters in healthy subjects.METHODS:Thir ty-three healthy subjects were enrolled.The ONH of both eyes were imaged four times by a swept-source-OCTA using a 3 mm×3 mm scanning protocol.Images of the radial peripapillary capillary were analyzed by a customized Matlab program,and the vessel density,fractal dimension,and vessel diameter index were measured.The repeatability of the four scans was determined by the intraclass correlation coefficient(ICC).The most well-centered optic disc from the four repeated scans was then selected for the interocular correlation and agreement analysis using the Pearson correlation coefficient,ICC and Bland-Altman plots.RESULTS:All swept-source-OCTA ONH parameters exhibited certain repeatability,with ICC>0.760 and coefficient of variation(CoV)≤7.301%.The obvious interocular correlation was observed for papillary vessel density(ICC=0.857),vessel diameter index(ICC=0.857)and fractal dimension(ICC=0.906),while circumpapillary vessel density exhibited moderate interocular correlation(ICC=0.687).Bland-Altman plots revealed an agreement range of-5.26%to 6.21%for circumpapillary vessel density.CONCLUSION:OCTA ONH parameters demonstrate good repeatability in healthy subjects.The interocular correlations of papillary vessel density,fractal dimension and vessel diameter index are high,but the correlation for circumpapillary vessel density is moderate.