The Sphenopalatine Ganglion: Anatomy, Pathophysiology, and Therapeutic Targeting in Headache.

The sphenopalatine ganglion (SPG) has attracted the interest of practitioners treating head and face pain for over a century because of its anatomical connections and role in the trigemino-autonomic reflex. In this review, we discuss the anatomy of the SPG, as well as what is known about its role in the pathophysiology of headache disorders, including cluster headache and migraine. We then address various therapies that target the SPG, including intranasal medication delivery, new SPG blocking catheter devices, neurostimulation, chemical neurolysis, and ablation procedures.

Percutaneous and Endoscopic Adhesiolysis in Managing Low Back and Lower Extremity Pain: A Systematic Review and Meta-analysis.

BACKGROUND: Chronic refractory low back and lower extremity pain is frustrating to treat. Percutaneous adhesiolysis and spinal endoscopy are techniques which can treat chronic refractory low back and lower extremity pain.Percutaneous adhesiolysis is performed by placing the catheter into the tissue plane at the ventrolateral aspect of the foramen so that medications can be injected. Adhesiolysis is used both for pain caused by scarring which is not resistant to catheter placement and other sources of pain, including inflammation in the absence of scarring.Mechanical lysis of scars with a catheter may or may not be necessary for percutaneous adhesiolysis to be effective. Spinal endoscopy allows direct visualization of the epidural space and has the possibility to use laser energy to treat pathology. STUDY DESIGN: A systematic review of the effectiveness of percutaneous adhesiolysis and spinal endoscopic adhesiolysis to treat chronic refractory low back and lower extremity pain. OBJECTIVE: To evaluate and update the effectiveness of percutaneous adhesiolysis and spinal endoscopic adhesiolysis to treat chronic refractory low back and lower extremity pain. METHODS: The available literature on percutaneous adhesiolysis and spinal endoscopic adhesiolysis in treating persistent low back and leg pain was reviewed. The quality of each article used in this analysis was assessed. The level of evidence was classified on a 5-point scale from strong, based upon multiple randomized controlled trials to weak, based upon consensus, as developed by the U.S. Preventive Services Task Force (USPSTF) and modified by ASIPP. Data sources included relevant literature identified through searches of PubMed and EMBASE from 1966 to September 2015, and manual searches of the bibliographies of known primary and review articles. OUTCOME MEASURES: Pain relief of at least 50% and functional improvement of at least 40% were the primary outcome measures. Short-term efficacy was defined as improvement of 6 months or less; whereas, long-term efficacy was defined more than 6 months. RESULTS: For this systematic review, 45 studies were identified. Of these, for percutaneous adhesiolysis there were 7 randomized controlled trials and 3 observational studies which met the inclusion criteria. For spinal endoscopy, there was one randomized controlled trial and 3 observational studies. Based upon 7 randomized controlled trials showing efficacy, with no negative trials, there is Level I or strong evidence of the efficacy of percutaneous adhesiolysis in the treatment of chronic refractory low back and lower extremity pain. Based upon one high-quality randomized controlled trial, there is Level II to III evidence supporting the use of spinal endoscopy in treating chronic refractory low back and lower extremity pain. CONCLUSION: The evidence is Level I or strong that percutaneous adhesiolysis is efficacious in the treatment of chronic refractory low back and lower extremity pain. Percutaneous adhesiolysis may be considered as a first-line treatment for chronic refractory low back and lower extremity pain. The evidence is Level II to III that spinal endoscopy is effective in the treatment of chronic refractory low back and lower extremity pain. KEY WORDS: Spinal pain, chronic low back pain, post lumbar surgery syndrome, epidural scarring, adhesiolysis, endoscopy, radicular pain.

Efficacy of Epidural Injections in Managing Chronic Spinal Pain: A Best Evidence Synthesis.

BACKGROUND: Epidural injections have been used since 1901 in managing low back pain and sciatica. Spinal pain, disability, health, and economic impact continue to increase, despite numerous modalities of interventions available in managing chronic spinal pain. Thus far, systematic reviews performed to assess the efficacy of epidural injections in managing chronic spinal pain have yielded conflicting results. OBJECTIVE: To evaluate and update the clinical utility of the efficacy of epidural injections in managing chronic spinal pain. STUDY DESIGN: A systematic review of randomized controlled trials of epidural injections in managing chronic spinal pain. METHODS: In this systematic review, randomized trials with a placebo control or an active-control design were included. The outcome measures were pain relief and functional status improvement. The quality of each individual article was assessed by Cochrane review criteria, as well as the Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB). Best evidence synthesis was conducted based on the qualitative level of evidence (Level I to V). Data sources included relevant literature identified through searches of PubMed for a period starting in 1966 through August 2015; Cochrane reviews; and manual searches of the bibliographies of known primary and review articles. RESULTS: A total of 52 trials met inclusion criteria. Meta-analysis was not feasible. The evidence in managing lumbar disc herniation or radiculitis is Level II for long-term improvement either with caudal, interlaminar, or transforaminal epidural injections with no significant difference among the approaches. The evidence is Level II for long-term management of cervical disc herniation with interlaminar epidural injections. The evidence is Level II to III in managing thoracic disc herniation with an interlaminar approach. The evidence is Level II for caudal and lumbar interlaminar epidural injections with Level III evidence for lumbar transforaminal epidural injections for lumbar spinal stenosis. The evidence is Level III for cervical spinal stenosis management with an interlaminar approach. The evidence is Level II for axial or discogenic pain without facet arthropathy or disc herniation treated with caudal or lumbar interlaminar injections in the lumbar region; whereas it is Level III in the cervical region treated with cervical interlaminar epidural injections. The evidence for post lumbar surgery syndrome is Level II with caudal epidural injections and for post cervical surgery syndrome it is Level III with cervical interlaminar epidural injections. LIMITATIONS: Even though this is a large systematic review with inclusion of a large number of randomized controlled trials, the paucity of high quality randomized trials literature continues to confound the evidence. CONCLUSION: This systematic review, with an assessment of the quality of manuscripts and outcome parameters, shows the efficacy of epidural injections in managing a multitude of chronic spinal conditions.

Fibrin-targeted block copolymers for the prevention of postsurgical adhesions.

Despite advances in surgical methods, postsurgical adhesions (PSA) remain a significant clinical challenge affecting millions of patients each year. These permanent fibrous connections between tissues result from the bridging of wounded internal surfaces by an extended fibrin gel matrix (FGM). Adhesion formation is a result of a systems level convergence of wound healing pathways, complicating the design of materials that could inhibit their occurrence. In this study, a systematic approach that identifies key material properties required for functional performance optimization was used to design a new fibrin-targeted PSA prevention material. A series of multifunctional polymers with varied molecular architectures was synthesized to investigate the effect of changing polymer structural parameters on the ability to disrupt the formation of an extended FGM. Initial studies in a murine adhesion model demonstrated a statistically significant reduction in the degree of PSA formation, demonstrating the potential value of this systematic approach.

Block copolymers for the rational design of self-forming postsurgical adhesion barriers.

Post-surgical adhesions, abnormal fibrous linkages between adjacent tissue surfaces, represent one of the most common and significant complications facing surgical recovery today. Physical barriers and gels have been the most successful at limiting their formation, yet are not effective in cases where the pro-adhesive site is either unknown or difficult to reach (e.g. during laparoscopic surgery). In this work, poly(methacrylic acid-co-t-butylmethacrylate)-b-poly(ethylene glycol (M(N) = 1000) methacrylate) diblock and statistical copolymers were synthesized as a platform for designing self-forming adhesion barriers, which can attach to exposed pro-adhesive sites through binding with the positively charged extracellular matrix, basement membrane proteins and deposited fibrin. An experimental model based upon a quartz crystal microbalance with dissipation was developed to test the diblock copolymers ability (i) to adsorb to an amine-terminated self-assembled monolayer, and (ii) to inhibit subsequent protein adsorption. These results were also confirmed using an in vitro cell attachment model. As the mole fraction of methacrylic acid content increased, polymer adsorption increased. All synthesized diblock copolymers investigated provided high resistance to protein adsorption, with blockade ranging from 55% to 81%. Except for the uncharged control polymers, the ability of these materials to resist cellular attachment showed similar trends, with the suppression of attachment approaching 75%. Energy dissipation analysis and variable-angle spectroscopic ellipsometry revealed two competing adsorption mechanisms depending on the molecular properties of the polymer.

Association between homocyst(e)ine levels and risk of vascular events.

Homocyst(e)ine is a novel risk factor in vascular disease. First observations of vascular lesions in children with high blood homocyst(e)ine levels due to severe inborn enzyme deficiencies led to the hypothesis that elevated blood homocyst(e)ine levels might be a risk factor for vascular disease. A substantial body of evidence on the role of the homocyst(e)ine in the development of coronary and carotid artery disease, myocardial infarction, stroke, deep vein thrombosis and other disorders has been accumulated over the last 30 years. Cross-sectional and case-control studies provide initial and the strongest support for the hypothesis, followed by results from the prospective cohorts. Infrequent cases of homozygous mutations of the key enzymes in the homocyst(e)ine metabolism chain are able to produce extreme homocyst(e)inemia and early vascular lesions. More frequently, heterozygous enzyme mutations and deficiencies of folate and vitamins B6 and B12 cause mild to moderate homocyst(e)inemia, which is still strongly associated with the increased risk of vascular events. Elevated homocyst(e)ine levels may be effectively managed with adequate folate, B12 and B6 intake in doses comparable to or above FDA recommendations. Whether correction of elevated homocyst(e)ine levels with vitamins is helpful in prevention and treatment of vascular events remains unknown and is under investigation in ongoing clinical trials (VISP, VITATOPS). No consensus on homocyst(e)ine management is available at the present time.

Selection of anticoagulants or antiplatelet-aggregating agents for prevention of stroke.

Stroke is one of leading causes of mortality and morbidity in the United States. Stroke prevention includes treatment of the stroke risk factors and long-term use of antithrombotic agents. Various agents have been studied for stroke prevention and other trials are ongoing. The aim of this article is to provide an overview of the recent guidelines, recommendations, and clinical trial results using antithrombotic therapy for stroke prevention.