Comparison of contrast flow and clinical effectiveness between a modified paramedian interlaminar approach and transforaminal approach in cervical epidural steroid injection.

BACKGROUND: The different methods of cervical epidural injection include the median or paramedian interlaminar (PI) approach and the transforaminal (TF) approach. We hypothesized that the modified PI (mPI) approach could deliver drugs suitably and safely into the anterior epidural space compared with the TF approach. METHODS: A total of 62 patients were randomized into either the mPI group (n=31) or the TF group (n=31). Contrast to the anterior epidural space (primary outcome, grade 1-3), vascular uptake and discomfort were assessed. Furthermore, pain intensity in the arm and neck [numeric rating scale (NRS)] and the degree of symptoms (5-point Likert scale) before the procedure and 2 weeks, 1 and 3 months following the procedure were compared between two groups. Effectiveness (a secondary outcome) was defined as a ≥50% reduction on the NRS for arm and neck pain and a result of 3 or 4 on the Likert scale at 3 months following the procedure. RESULTS: Contrast to the anterior epidural space in the mPI group was significantly greater than that in the TF group (P=0.036). Vascular uptake and discomfort in the mPI group were significantly lower than those in the TF group (P<0.001, respectively). Of the patients in whom the procedure was effective, 24 (77.4%) were from the mPI group and 20 (64.5%) were from the TF group (P=0.263). CONCLUSION: This result suggests that the mPI approach allows for suitable and safe delivery of drugs into the anterior epidural space. TRIAL REGISTRY NUMBER: Institutional Review Board of Seoul National University Bundang Hospital (B-1206/159-004) and Clinical Research Information Service (KCT0000626).

Effects of pregabalin on the activity of glutamate transporter type 3.

BACKGROUND: Pregabalin, (S)-3-aminomethyl-5-methyl hexanoic acid, is a ligand for the α2δ subunit (a component of voltage-gated calcium channels) and has analgesic and anticonvulsant properties. Glutamate uptake by glutamate transporters may be a mechanism for these properties. We investigated the effects of pregabalin on the activity of the neuronal glutamate transporter type 3 (EAAT3). METHODS: EAAT3 was expressed in Xenopus laevis oocytes. Two-electrode voltage clamping was used to record membrane currents before, during, and after applying l-glutamate (30 µM) in the presence or absence of pregabalin. Currents were also measured in oocytes pretreated with a protein kinase C (PKC) activator (phorbol-12-myristate-13-acetate, PMA), PKC inhibitors (chelerythrine or staurosporine), or a phosphatidylinositol-3-kinase (PI3K) inhibitor wortmannin. RESULTS: The exposure of the oocytes injected with EAAT3 mRNA to serial concentrations of pregabalin (0.06-60 µM) significantly increased their responses to 30 µM l-glutamate. A kinetic study showed that pregabalin significantly increased V(max) without changing K(m). Treatment of oocytes with PMA, pregabalin, or pregabalin plus PMA significantly increased transporter currents vs controls, but treatment with PMA plus pregabalin did not increase the responses further vs PMA or pregabalin alone. In addition, pretreatment of oocytes with two PKC inhibitors (chelerythrine or staurosporine), or inhibitor wortmannin, significantly reduced basal and pregabalin-enhanced EAAT3 activity. CONCLUSIONS: Pregabalin increased EAAT3 activity and PKC and PI3K were involved. This may explain the analgesic effect of pregabalin in neuropathic pain.

Efficacy of pulsed electromagnetic therapy for chronic lower back pain: a randomized, double-blind, placebo-controlled study.

This randomized, double-blind, placebo-controlled clinical trial studied the effectiveness of pulsed electromagnetic therapy (PEMT) in patients with chronic lower back pain. Active PEMT (n = 17) or placebo treatment (n = 19) was performed three times a week for 3 weeks. Patients were assessed using a numerical rating scale (NRS) and revised Oswestry disability scores for 4 weeks after therapy. PEMT produced significant pain reduction throughout the observation period compared with baseline values. The percentage change in the NRS score from baseline was significantly greater in the PEMT group than the placebo group at all three time-points measured. The mean revised Oswestry disability percentage after 4 weeks was significantly improved from the baseline value in the PEMT group, whereas there were no significant differences in the placebo group. In conclusion, PEMT reduced pain and disability and appears to be a potentially useful therapeutic tool for the conservative management of chronic lower back pain.

The effect of gynaecological laparoscopic surgery on cerebral oxygenation.

During gynaecological laparoscopic surgery, alterations in cerebral blood flow and intracranial pressure are frequently reported. These changes affect cerebral perfusion pressure and thus may affect cerebral oxygenation. In this prospective study, the effect of gynaecological laparoscopic surgery on cerebral oxygenation was examined by following the changes in regional cerebral oxygen saturation (rSo2). Twenty-four female patients were enrolled. The mean rSo2 was 65.5 +/- 5.4% at baseline before surgery, 60.8 +/- 5.6% when the patient was placed in the Trendelenburg position, 57.1 +/- 9.3% after creation of pneumoperitoneum, and 64.0 +/- 7.3% after the completion of surgery. During the period of pneumoperitoneum, rSo2 fell below 50% in two hypercapnic patients. In comparison with baseline, rSo2 declined significantly in the Trendelenburg position. The creation of pneumoperitoneum itself did not decrease the average rSo2 value further unless the patients were hypercapnic.

Comparison between high and low molecular weight hyaluronates in knee osteoarthritis patients: open-label, randomized, multicentre clinical trial.

Efficacy and safety of high and low molecular weight hyaluronates in knee osteoarthritis patients were compared in a randomized, open-label trial. Patients in the high molecular weight hyaluronate group were treated once weekly for 3 weeks and in the low molecular weight group once weekly for 5 weeks. We evaluated weight-bearing pain, degree of flexion, swelling and knee tenderness; frequency and amount of rescue medication; patient and investigator global assessment of pain, and safety over 12 weeks after final injection of study medication. Significant improvements in pain and WOMAC-Likert scores were observed in both groups, but not between groups. Knee joint pain improvement was noted in both groups by patients and investigators during follow-up. Close correlation was observed between patient- and investigator-reported data. There was no significant difference in side-effects between the groups. In conclusion, the efficacy and safety of high and low molecular weight hyaluronate are similar.

Recommendations for HER2 testing in the UK.

Determining the HER2 status of breast carcinomas is a prerequisite for the use of the monoclonal antibody trastuzumab (Herceptin), which has recently been licensed for the treatment of metastatic disease. This necessitates a test based on archival material. The preferred analyses are immunohistochemistry with fluorescent in situ hybridisation (FISH) as a follow up test for ambiguous results. Guidelines have been developed for standardised, well controlled procedures for the provision of reliable results. A group of three reference laboratories has been established to provide advice, quality assurance, and materials, where needed.

C-arm-guided pudendal nerve block: a new technique.

Pudendal nerve block (PNB) is an effective diagnostic and/or treatment method for perineal pain. Various approach techniques, such as transperineal, transvaginal, computerised tomography (CT)- or sono-guided approach, have been suggested for this block. However, they have some limitations, such as high cost, difficulty to perform in practice, inaccurate and unreliable results and inconvenience. To overcome these limitations, we first tried C-arm-guided approach for accomplishing PNB in the prone position. Under the optimal ischial spine view of C-arm fluoroscopy, the block needle was placed on the tip of the ischial spine. Then a mixed solution for the block was administered. All of the 25 patients enrolled in this study were blocked successfully using this method. No side-effects or complications were observed in relation to the block. We concluded that the C-arm-guided approach for PNB is an effective alternative to the existing techniques, which can overcome their limitations.

Generation of ultrashort electron bunches by colliding laser pulses.

A proposed laser-plasma-based relativistic electron source [E. Esarey et al., Phys. Rev. Lett. 79, 2682 (1997)] using laser-triggered injection of electrons is investigated. The source generates ultrashort electron bunches by dephasing and trapping background plasma electrons undergoing fluid oscillations in an excited plasma wake. The plasma electrons are dephased by colliding two counterpropagating laser pulses which generate a slow phase velocity beat wave. Laser pulse intensity thresholds for trapping and the optimal wake phase for injection are calculated. Numerical simulations of test particles, with prescribed plasma and laser fields, are used to verify analytic predictions and to study the longitudinal and transverse dynamics of the trapped plasma electrons. Simulations indicate that the colliding laser pulse injection scheme has the capability to produce relativistic femtosecond electron bunches with fractional energy spread of order a few percent and normalized transverse emittance less than 1 mm mrad using 1 TW injection laser pulses.