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Vijay Singh

Publications and source records attributed to Vijay Singh.

53 records · Page 3Linked to original sources
PubMed2002

Temperature-enhanced alumina HPLC method for the analysis of wax esters, sterol esters, and methyl esters.

Previous attempts at separating nonpolar lipid esters (including wax esters, sterol esters, and methyl esters) have achieved only limited success. Among the several normal-phase methods tested, a single recent report of a method employing an alumina column at 30 degrees C with a binary gradient system was the most promising. In the current study, modification of the alumina method by increasing the column temperature to 75 degrees C improved the separation of standards of wax esters and sterol esters. Elevated column temperature also enhanced the separation of FAME with differing degrees of unsaturation. Evidence was also presented to indicate that the method similarly separated phytosterol esters, based on their levels of unsaturation. With the increased interest in phytosterol- and phytostanol-ester enriched functional foods, this method should provide a technique to characterize and compare these products.

Aluminum Oxide↗
PubMed2002

Epidural lysis of adhesions and myeloscopy.

Chronic low back pain is one of the most common ailments in modern medicine, with as many as 79% of patients with acute pain continuing to suffer with chronic or recurrent low back pain 1 year after its onset. Lumbar epidural fibrosis and post-lumbar laminectomy syndrome are increasingly recognized as being responsible for persistent low back pain. Estimations show that approximately 5% to 40% of lumbar surgeries result in failed back surgery syndrome. Epidural adhesiolysis with myeloscopy is an interventional technique based on the premise that the three-dimensional visualization of the contents of the epidural space provides the physician with the ability to directly visualize the structures, perform appropriate adhesiolysis, and administer drugs specifically to the target. This review describes pathophysiologic aspects, purposes and goals, rationale and indications, complications, and effectiveness of epidural lysis of adhesions with myeloscopy.

Anti-Inflammatory Agents↗
PubMed2002

New strategies for the prevention of radiation injury: possible implications for countering radiation hazards of long-term space travel.

New strategies for the prevention of radiation injuries are currently being explored with the ultimate aim of developing globally radioprotective, nontoxic pharmacologics. The prophylactic treatments under review encompass such diverse pharmacologic classes as novel immunomodulators, nutritional antioxidants, and cytokines. An immunomodulator that shows promise is 5-androstenediol (AED), a well-tolerated, long-acting androstene steroid with broad-spectrum radioprotective attributes that include not only protection against acute tissue injury, but also reduced susceptibility to infectious agents, as well as reduced rates of neoplastic transformation. Other potentially useful radioprotectants currently under study include the nutraceutical vitamin E and analogs, a chemically-engineered cytokine, interleukin-1beta, and a sustained-release formulation of an aminothiol, amifostine. Results suggest that a new paradigm is evolving for the prophylaxes of radiation injuries, based on use of newly identified, nontoxic, broad-spectrum prophylactic agents whose protective action may be leveraged by subsequent postexposure use of cytokines with organ-specific reparative functions.

Animals↗
PubMed2002

Evaluation of the prevalence of facet joint pain in chronic thoracic pain.

The role of zygapophysial (facet) joints in chronic thoracic pain has received very little attention with only a few publications discussing these joints as sources of pain. In contrast, facet joints have been implicated as responsible for chronic pain in a significant proportion of patients with chronic neck and low back pain. However, thoracic spinal pain, though less common, has been reported to be as disabling as neck and low back pain. This study was designed to evaluate all the consecutive patients presenting with thoracic pain and undergoing diagnostic medial branch blocks during 2001. All the patients failed conservative management with physical therapy, chiropractic therapy and drug therapy. All patients underwent diagnostic facet joint nerve blocks using lidocaine 1%, initially followed by bupivacaine 0.5% on separate occasions. Results showed that 46 patients underwent single blocks with lidocaine and 36 of these patients, or 78%, were positive for facet joint pain, reporting a definite response. Confirmatory blocks with bupivacaine were performed in all patients who were lidocaine-positive, with 61%, or 48% of the total sample of the lidocaine-positive group, reporting a definite response with improvement in their pain. Thus, comparative local anesthetic blocks showed the prevalence of facet joint pain to be 48%, with single blocks carrying a false-positive rate of 58%.

Journal Article↗
PubMed2002

Is there correlation of facet joint pain in lumbar and cervical spine? An evaluation of prevalence in combined chronic low back and neck pain.

Among the chronic pain problems, pain emanating from cervical and lumbar regions, independently or in combination, constitutes a significant and frequently encountered problem in interventional pain management practices. This study was designed to test the assumption that patients presenting with chronic low back pain of lumbar facet joint origin may also present with chronic neck pain of facet joint origin. Considering that many studies show the prevalence of facet joint involvement in chronic low back pain as ranging from 15% to 45% compared to prevalence of involvement of cervical facets in chronic neck pain, ranging from 54% to 60%, we sought to evaluate the correlation between lumbar facet joint to cervical facet joint pain. One hundred twenty consecutive patients with chronic neck and low back pain were evaluated utilizing controlled diagnostic blocks with lidocaine and bupivacaine. The results showed prevalence of cervical facet joint pain in 67% of the patients with a false-positive rate of 63% with a single block, whereas the prevalence of lumbar facet joint pain was seen in 40% of the patients with a 30% false-positive rate with a single block in patients presenting with chronic low back and neck pain. There was also significant correlation noted with 94% of the patients with confirmed lumbar facet joint pain also presenting with cervical facet joint pain.

Journal Article↗
PubMed2002

Medial branch neurotomy in management of chronic spinal pain: systematic review of the evidence.

Zygapophysial or facet joints have been implicated as cause of low back, mid back, upper back and neck pain with referred pain. Cervical, thoracic and lumbar facet joints are innervated by the medial branches of the dorsal rami. Zygapophysial (facet) joints have been implicated as the source of chronic pain in 15% to 45% of the patients with chronic low back pain, 54% to 60% of the patients with chronic neck pain and 48% of the patients with thoracic pain. A systematic review of the evidence of effectiveness of radiofrequency denervation in the management of chronic spinal pain was undertaken. This review included randomized clinical trials, as well as non-randomized or observational studies in the analysis. Literature search included MEDLINE, EMBASE, systematic reviews, narrative reviews, cross-references to the reviews and various published trials; and peer reviewed abstracts from scientific meetings during the past two years. An algorithmic approach was followed in study evaluation with a description of inclusion and exclusion criteria. A set of high-performing scales or checklists pertaining to randomized clinical trials and observational trials derived from the Agency for Healthcare Research and Quality (AHRQ) was utilized; Systems to Rate the Strength of Scientific Evidence. Qualitative analysis was conducted, using five levels of evidence for effectiveness of medial branch neurotomy. Our search strategy identified over 1,000 citations as the result of electronic and manual screening. A total of 7 randomized trials of radiofrequency neurotomy for spinal pain were identified. However, only 4 related to medial branch neurotomy. Two of the four met the inclusion criteria. Among the multiple observational studies considered for inclusion, 4 prospective evaluations were included in the systematic review. In addition, 3 retrospective evaluations were also included. Two randomized trials comprised of 27 patients receiving active treatment. The first study consisted of cervical facet joint pain and the second consisted of lumbar facet joint pain. Both studies showed positive results. Similar to randomized trials, prospective, as well as retrospective evaluations showed positive evidence, both in short-term and long-term. The results of this systematic review of 2 well-designed randomized trials, 4 prospective well-designed trials without randomization and 3 retrospective evaluations provided strong evidence that radiofrequency denervation offers short-term relief and moderate evidence of long-term pain relief of facet joint origin.

Journal Article↗
PubMed2002

Effectiveness of caudal epidural injections in discogram positive and negative chronic low back pain.

Epidural steroid injections are the most commonly used procedures to manage chronic low back pain in interventional pain management settings. The overall effectiveness of epidural steroid injections has been highly variable, and in the role has not been evaluated in patients discographically evaluated. One hundred consecutive patients, without evidence of disc herniation or radiculitis, who had failed to respond to conservative management with physical therapy, chiropractic and/or medical therapy, underwent discography utilizing strict criteria of concordant pain, and negative adjacent discs, after being judged to be negative for facet joint and/or sacroiliac joint pain utilizing comparative local anesthetic blocks. Any other type of response was considered negative. This study included 62 patients, who underwent caudal epidural steroid injections with Sarapin. They included Group I, comprised of 45 of 55 patients negative on provocative discography; and Group II, with 17 of 45 patients with positive provocative discography. Results showed that there was significant improvement in patients receiving caudal epidural injections, with a decrease in pain associated with improved physical, functional, and mental status; decreased narcotic intake, and increased return to work. The study showed that at 1 month, 100% of the patients evaluated showed significant improvement in both groups; this declined to 86% at 3 months in Group I, but remained at 100% in Group II, declining to 60% and 64% at 6 months in Group I and Group II, respectfully, with administration of one to three injections. Analysis with one to three injections, which included all (62) patients showed significant relief in 71% and 65% of the patients at 1 month, in 67% and 65% at 3 months, and in 47% and 41% at 6 months, in Group I and Group II, respectively. In conclusion, caudal epidural injections with or without steroids is an effective modality of treatment in managing chronic, persistent low back pain failing to respond to conservative modalities of treatments, in patients negative for facet joint and sacroiliac joint pain, whether positive or negative, on evaluation with provocative discography.

Journal Article↗
PubMed2002

Evaluation of influence of gender, occupational injury, and smoking on chronic low back pain of facet joint origin: a subgroup analysis.

The prevalence of persistent low back pain secondary to involvement of lumbosacral facet joints has been described in controlled studies as varying from 15% to 52% based on types of population and settings studied. Previous studies have shown variances in elderly populations, and postlumbar laminectomy patients. But no variations were observed in obese patients or patients with somatization disorder. Based on the individual results, it appears that facet joint pain may be less prevalent in patients with occupational injury and more prevalent in women and smokers. This analysis was based on a combination of the results of two previous studies with a total number of 320 patients to evaluate the influence of gender, occupational injury and smoking on prevalence of facet joint pain. Facet joints were investigated with diagnostic blocks initially using lidocaine 1%, followed by bupivacaine 0.25%, usually 2 to 4 weeks apart in these studies. The prevalence of facet joint pain in men was 38% (95% CI, 29% to 47%) compared to 43% (95% CI, 36% to 50%) in women; 43% (95% CI, 33% to 53%) in non-smokers, compared to 41% (95% CI, 30% to 52%) in heavy smokers; and 28% (95% CI, 18% to 38%) in occupational injury patients compared to 44% (95% CI, 36% to 52%) with a history of gradual onset. False-positive rates varied from 28% to 46%. In conclusion, based on the results of this evaluation, women and men, smokers and nonsmokers suffer with similar prevalence rates of facet joint pain in chronic low back pain; whereas occupational injury patients suffer with lesser prevalence (28%) compared to patients with gradual onset (44%) of low back pain.

Journal Article↗
PubMed2002

Understanding psychological aspects of chronic pain in interventional pain management.

There is no doubt that chronic pain is recognized as a biopsychosocial phenomenon in which biological, psychological, and social factors dynamically interact with each other. Thus, the role of psychological factors and understanding chronic, persistent disabling pain has been well recognized, but poorly understood. Approximately 1/2 to 2/3 of all patients diagnosed with chronic pain manifest to various levels of psychological distress. Chronic pain and psychological disorders are the two most common elements in the United States. Statistics show that, approximately 22% of Americans suffer from a diagnosable mental disorder in a given year. In addition, 28% of the American population suffers with chronic pain. Depression in chronic pain is the most common condition, followed by generalized anxiety disorder, somatization disorder, and drug dependence. However, psychogenic pain appears to be the least prevalent of all psychopathological issues. Chronic pain disability is a complex psychosocial economic phenomenon. There is no data in the literature with regards to treatment of personality disorders, anxiety disorders, and somatization disorders in managing chronic pain. In contrast, treatment of depression and the influence of treatment on outcomes have been studied to some extent. In conclusion, patients with chronic pain frequently have psychopathology - most often common depressive disorders, anxiety disorders, somatization disorders, drug dependence and occasionally personality disorders. This review discusses various issues involved with psychopathology in chronic pain including epidemiology; relationship of psychopathology to pain; influence of depression, generalized anxiety disorder, somatization, and personality disorders on chronic pain, along with diagnosis and management in interventional pain management.

Journal Article↗
PubMed2002

Review of chronic low back pain of facet joint origin.

Chronic low back pain secondary to involvement of the facet joints is a common problem. Facet joints have been recognized as potential sources of back pain since 1911. Multiple authors have described distributions of pain patterns of facet joint pain. The facet joints are paired diarthrodial articulations between the posterior elements of the adjacent vertebrae. Lumbar facet joints are innervated by medial branches of the dorsal rami of the spinal nerves from the L1 to L4 levels. At L5, the dorsal ramus travels between the ala of the sacrum and its superior articular process and divides into medial and lateral branches at the caudal edge of the process. Each segmental medial branch of the dorsal ramus supplies at least two facet joints. The existence of lumbar facet joint pain claims has a preponderance of evidence, even though there are a few detractors. Multiple studies utilizing controlled diagnostic blocks have established the prevalence of lumbar facet joint involvement in patients with chronic low back pain, as ranging from 15% to 52%, based on type of population and setting studied. Long-term therapeutic benefit has been reported from three types of interventions in managing lumbar facet joint pain, including intraarticular injections, medial branch blocks and neurolysis of medial branches. This review will discuss chronic low back of facet joint origin and covers anatomy, pathophysiology, diagnosis, and various aspects related to treatment, including clinical effectiveness, cost effectiveness, technical aspects and complications.

Journal Article↗
PubMed2002

Prevalence of cervical facet joint pain in chronic neck pain.

Neck pain is considered to be one of the most common chronic pain conditions in modern society. Various structures identified as capable of transmitting pain in the cervical spine include facet joints, intervertebral discs, nerve root dura, ligaments, fascia, and muscles. The prevalence of cervical facet joint pain in patients with chronic pain after whiplash has been determined as 54% to 60%. However, the prevalence of chronic cervical facet joint pain has not yet been determined in a heterogenous population or in patients with cervical spine pain of idiopathic origin in a controlled environment. This study evaluated 160 patients seen in one interventional pain management practice in a non-university setting. Cervical facet joints were investigated with diagnostic blocks using lidocaine 1% preservative free initially, followed by bupivacaine 0.25%, usually 2 to 4 weeks apart. The study population consisted of 76 women and 30 men aged 43 +/- 13 years of age (mean +/- SD). Mode of onset of neck pain was determined as following a traumatic incident in 48% of the patients, whereas it was with gradual onset without an identifiable specific incident in the remaining 55 patients (52%). Eighty-one or 70% of the patients (70%) reported a definite response to lidocaine blocks. Confirmatory blocks with bupivacaine were performed in 81 patients with 64 patients with 60% of the total sample, or 79%, of the lidocaine-positive group reporting definite response with improvement in their pain. Thus, a prevalence rate of facet joint pain in chronic neck pain was determined to be 60% (95% CI, 50%-70%), with a false positive rate of controlled diagnostic blocks of 40% (95% CI, 34%-46%).

Journal Article↗
PubMed2002

Percutaneous disc decompression using coblation (nucleoplasty) in the treatment of chronic discogenic pain.

Clinical outcome data was analyzed for 67 patients with contained disc herniation who underwent percutaneous disc decompression procedure using Coblation(R) technology, also referred to as Nucleoplasty after failing to respond to conservative management. Patients presented with clinical symptoms of discogenic low back pain and/or leg pain and were not considered candidates for open surgery. Follow-up data was collected up to 12 months. Patient gender distribution was 70% female, 30% male, with a mean age of 44 years. The onset of the pain was predominantly of nontraumatic origin with an average duration of pain of 5.4 years ranging from 4 months to 29 years with history of previous surgical intervention in 13% of the patients. At 1 year, 80% of the patients demonstrated statistically significant improvement in numeric pain scores. Average pre-procedure pain level for all patients was reported as 6.8 while average pain level was 4.1 at the 12 month follow-up period. Statistically significant improvement was observed in 62%, 59%, and 60% of patients in sitting, standing, and walking ability at 12 months, respectively. The results of this analysis indicated that PDD using Coblation technology, also referred to as Nucleoplasty, is an effective procedure for patients presenting with discogenic back and/or leg pain who have failed conservative therapies and are not considered candidates for open surgical interventions.

Journal Article↗
PubMed2002

National All Schedules Prescription Electronic Reporting Act (NASPER): balancing substance abuse and medical necessity.

The National All Schedules Prescription Electronic Reporting Act, or NASPER, is a bill proposed by the American Society of Interventional Pain Physicians to provide and improve patient access with quality care, and protect patients and physicians from deleterious effects of controlled substance misuse, abuse and trafficking. Controlled prescription drugs, including narcotic analgesics, anxiolytics, anti-depressants, stimulants, and sedative-hypnotics play a significant and legitimate role in interventional pain management practices in managing chronic pain and related disorders. Based on the 1997 household survey on drug abuse it is estimated that 76.9 million Americans had used an illicit drug at least once in their life. In 1997, 4.2 million people used analgesics, 2.1 million used tranquillizers, and an additional 2.3 million people used various other drugs, including sedatives, tranquillizers, etc. The non-medical use of prescription drugs exceeds that of all illicit substances except for marijuana and hashish. The report on epidemiology trends in drug abuse, based on community epidemiology work group analysis showed continued increase of abuse of prescription drugs in urban, suburban, and rural areas. The most commonly abused drugs include oxycodone, hydrocodone, hydromorphone, morphine, codeine, clonazepam, alprazolam, lorazepam, diazepam and carisoprodol. The diversion of prescription controlled substances to illicit channels is a public health and safety issue. This review describes the role of controlled substances in chronic pain management, prevalence and economic impact of controlled substance abuse, prescription accountability, effectiveness of prescription monitoring programs, and rationale for national controlled substance electronic reporting system.

Journal Article↗
PubMed2002

Role of caudal epidural injections in the management of chronic low back pain.

Caudal epidural administration of corticosteroids is one of the commonly used interventions in managing chronic low back pain. Reports of the effectiveness of all types of epidural steroids have varied from 18% to 90%. Sicard, a radiologist, was the first to describe injection of dilute solutions of cocaine through the sacral hiatus into the epidural space in 1901, to treat patients suffering from severe, intractable sciatic pain or lumbago. This was followed by an explosion of reports and evolving interest in caudal epidural steroids with two additional reports in 1901 and numerous other reports over the years. The philosophy of epidural steroid injections is based on the premise that the corticosteroid delivered into the epidural space attains higher local concentrations over an inflamed nerve root and will be more effective than a steroid administered either orally or by intramuscular injection. The clinical effectiveness evaluations fill the literature with various types of reports including randomized clinical trials, prospective trials, retrospective studies, case reports, and meta-analyses. Evidence from all types of evaluations with regards to the clinical and cost-effectiveness of caudal epidural injections is encouraging. This review discusses various aspects of the role of caudal epidural injections in the management of chronic low back pain, including pathophysiology of low back pain, indications, clinical effectiveness and complications.

Journal Article↗