Comparison of efficacy of ultrasound-guided platelet rich plasma injection versus dry needling in lateral epicondylitis-a randomised controlled trial.

PURPOSE: To assess whether Ultrasound guided dry needling is adequate for both common extensor tendon tears and tendinosis or whether ultrasound guided platelet rich plasma (PRP) has a superior outcome when compared to dry needling when there are tears of the common extensor tendon. MATERIALS AND METHODS: This is a single-centre, single-blinded, randomised controlled trial conducted between November 2018 and April 2020. 40 patients diagnosed with lateral epicondylitis based on clinical and sonographic features and having comparable baseline characteristics were randomly assigned to the two study groups (dry needling and PRP). Inclusion criteria were patients aged 20 years or more who were symptomatic for at least 3 months with sonographic evidence of lateral epicondylitis. Exclusion criteria were complete tear of common extensor tendon confirmed on ultrasound and presence of other associated diseases like osteoarthritis of shoulder and elbow. RESULTS: There was significant improvement in the visual analogue scale pain score in PRP group compared to the dry needling group at 9 months. However, this difference was not evident at 3 and 6 months follow-up. Mean improvement in common extensor tendon thickness in PRP group (5.1 mm at 3 months and 4.3 mm at 6 months) was slightly better than dry needling (4.4 mm at 3 months and 4.0 mm at 6 months). There was no difference in tear (if present) healing between both groups at 3 months. However at 6 months follow up, PRP demonstrated significant (mean-2.5) healing in tear compared to dry needling (mean-3.1). CONCLUSION: Two injections of Ultrasound guided PRP are more beneficial non operative treatment compared to ultrasound guided dry needling, in lateral epicondylitis.

Comparison of effectiveness of abrasive and enzymatic action of whitening toothpastes in removal of extrinsic stains - a clinical trial.

OBJECTIVE: To compare the effectiveness of abrasive component (perlite/calcium carbonate) and enzymatic component (papain and bromelain) of whitening toothpaste in removal of extrinsic stains. METHODS: This study is a randomized, triple blind and parallel group study in which 90 subjects aged 18-40 years were included. At baseline, stains scores were assessed by Macpherson's modification of Lobene Stain Index and subjects were randomly assigned to two groups with 45 subjects in each. Group 1 used whitening toothpaste with enzymatic action and group 2 with abrasive action. After 1 month, stain scores were assessed for the effectiveness of the two toothpastes and 2 months later to check the stain prevention efficacy. Wilcoxson's test was used to compare between baseline 1 and 2 months stain scores, and Mann-Witney U-test was applied for intragroup comparison. RESULTS: The mean baseline total stain score for the subjects allocated to the enzymatic toothpaste was 37.24 ± 2.11 which reduced to 30.77 ± 2.48 in 1 month, and for the abrasive paste, total stain reduced from 35.08 ± 2.96 to 32.89 ± 1.95. The reductions in total stain scores with both the pastes were significant compared with baseline stain scores (at 1 month Group 1, P = 0.0233 and Group 2, P = 0.0324; at 2 months, Group 1 P = 0.0356). Both the toothpastes proved to be equally good in removal of extrinsic stains; however, the enzymatic paste showed better results as compared to abrasive toothpaste. CONCLUSION: Whitening toothpaste with abrasive action and enzymatic action are equally effective in removal of extrinsic stains; however, whitening toothpaste with abrasive action needs to be used with caution.

Development of botanical principles for clinical use in cancer: where are we lacking?

Development of drugs from plant sources (botanicals) for the treatment of cancer has not been successful in India, despite a plethora of medicinal plants and an equal number of experiments demonstrating anti-cancer activity of plant principles in vitro. There are several pitfalls in our approach to botanical drug development. Foremost is the lack of industry-academia collaborations in this field. Research goals in Indian academic institutions are generally short-term and mostly aimed at fulfilling the minimum requirements of a doctoral/MD or MPharm thesis. Secondly, quality assurance of herbal formulations is difficult to achieve and good manufacturing practices are expensive to implement. This could introduce bias during the biological evaluation of botanicals. A systematic approach covering a wide range of investigations including but not limited to mechanistic studies, potential herb-drug interactions, pharmacokinetics and bioavailability could help in the optimization of herbal formulations in the preclinical stage of development before they can be considered for clinical trials. Government initiatives such as Ayurveda, Unani, Siddha and Homeopathic have encouraged research in these areas, but are insufficient to promote focused and aggressive evaluation of potential herbs. Particular emphasis should be given to clinical pharmacokinetics, drug interactions and clinical trials in specific cancers for the evaluation of dosage, safety, efficacy and concomitant use with chemotherapy. Only such policies can result in meaningful evaluation of botanicals for cancer therapy.

Antinociceptive activity of Sesbania sesban (Linn) wood extracts, a preliminary study.

The wood of the plant Sesbania sesban, is reported to have antinociceptive activity. To validate its folk use in the treatment of pain, wood was extracted successively with petroleum ether, chloroform, ethyl acetate, ethanol, and water to produce respective extracts. The extracts (50 and 100 mg/kg, ip) were screened for antinociceptive activity using hot plate test and acetic acid-induced writhing test in mice. Petroleum ether, chloroform, and ethyl acetate extracts showed significant and dose-dependent activity in both the tests. In order to find out the involvement of opioid receptors, effect of naloxone (1 mg/kg, sc) on the action of extracts was checked in hot plate test. Petroleum ether, chloroform, and ethyl acetate extracts showed significant and dose dependant antinociceptive activity. The antinociceptive action of the extracts was blocked by naloxone, suggesting involvement of opioid receptors in the action.

Investigation of PEGylated derivatives of rosin as sustained release film formers.

The purpose of the present study was to investigate the potential use of two PEGylated derivatives of rosin (PD) as sustained release film forming materials. The derivatives differed chemically by their acid numbers--PD-1 with 120.93 and PD-2 with 88.19. The derivative films were characterized for surface morphology, water uptake-weight loss, angle of contact, water vapor transmission rate, mechanical properties and permeability study. Dissolution of diclofenac sodium (DS) and propranolol hydrochloride (PHL) as model drugs was studied from coated pellets. The films of derivatives with and without plasticizers were smooth and continuous. PD-2 films developed greater numbers of pores when in contact with phosphate buffer pH 6.8. The low weight loss, low angles of contact and high water vapor transmission rate of PD-2 films were related to presence of higher concentration of PEG esters. Higher tensile strength and percent elongation of PD-2 films was due to greater degree of internal plasticization of the derivative. The permeability of films to model drugs propranolol hydrochloride and diclofenac sodium was inversely proportional to the film thickness and dibutyl phthalate concentration in them; the permeability being greatest in PD-2 films containing 10% PEG 200. Dissolution rate of propranolol hydrochloride was higher from the coated pellets. The dissolution data followed zero order, Baker-Lonsdale equation and Hixon-Crowell equation of release kinetics with high correlation coefficients. The mechanism of drug release from these coated systems however followed class II transport (n > 1.0). The derivatives investigated could successfully retard release of the model drugs and offers an alternative to the conventionally used polymers.

Gastrointestinal and immunological responses of senior dogs to chicory and mannan-oligosaccharides.

Thirty-four senior dogs (pointers 8-11 years, beagles 9-11 years) were used to evaluate the effects of oligosaccharides on nutritional and immunological characteristics. Dogs were randomly allotted to treatments [1% chicory (CH), 1% mannan-oligosaccharide (MOS), 1% chicory + 1% MOS (CM), or no supplementation (control, CON)] in a parallel design with a 4 week baseline period followed by a 4 week treatment period. Dietary supplementation with MOS or CM tended (P = 0.07) to increase food intake due, in part, to an increase in fermentable fibre and a decrease in energy content of the diet. Although wet faecal output increased (P < 0.05) for dogs supplemented with MOS or CM, when corrected for food intake, no differences were noted. The CM treatment increased (P < 0.05) faecal score (1 = hard and dry, 5 = watery liquid), although these scores remained in a desirable range (3 to 3.5). Chicory supplementation increased (P = 0.07) fat digestibility. Chicory or MOS increased (P < or = 0.05) faecal bifidobacteria concentrations 0.4 and 0.5 log10 cfu/g DM, respectively, compared to the CON, while MOS decreased (P < 0.05) faecal E. coli concentrations. Oligosaccharides did not affect white blood cell (WBC) concentrations, but CH and CM tended to increase (P = 0.10) neutrophil concentrations compared to control dogs. Peripheral lymphocyte concentrations were decreased in dogs supplemented with MOS (P = 0.06) and CM (P < 0.05). Chicory and MOS alter faecal microbial populations and certain indices of the immune system of senior dogs.

The ratio of insoluble to soluble fiber components in soybean hulls affects ileal and total-tract nutrient digestibilities and fecal characteristics of dogs.

An experiment was conducted to evaluate the effects of soybean hulls (SH) containing varying ratios of insoluble:soluble fiber (I:S) on nutrient digestibilities and fecal characteristics of dogs. Ileally cannulated dogs (n = 6) were fed seven diets in a 6 x 7 Youden square arrangement of treatments. The seven diets included five SH-containing diets with I:S of 1.9, 2.7, 3.2, 5.2 or 7.2 and two diets containing either beet pulp (BP) or no supplemental fiber (control). Ileal digestibilities of DM, OM, CP, total dietary fiber (TDF), fat and gross energy (GE) were lower (P < 0.05) for dogs fed diets containing supplemental fiber compared with dogs fed the control diet. Fiber inclusion had a modest negative effect (P < 0.05) on total-tract DM, OM, fat and GE digestibilities compared with the control diet. Ileal digestibilities of DM and OM by dogs fed the SH treatments responded quadratically (P < 0.05) to I:S, with digestibility coefficients decreasing as the I:S approached 3.2. Highest ileal digestibilities were observed for diets with an I:S of 1.9 and 7.2. Similarly, a quadratic response (P < 0.05) was observed for digestibility of total amino acids at the ileum. Fecal outputs were lower (P < 0.001) when dogs consumed the control diet vs. fiber-containing diets. Among the SH-containing diets, there was a linear increase in fecal output as I:S increased (P = 0.031). The I:S in the diet affects DM and OM digestibilities at the ileum and affects fecal output, indicating that optimization of this ratio is desirable.

Single incision for implanting a vagal nerve stimulator system (VNSS): technical note.

BACKGROUND: A technique for implanting the vagal nerve stimulator system through a single incision is described. METHOD: A transverse incision is made in the lower part of the neck. Subcutaneous (s.c.) dissection is then done over the clavicle into the infraclavicular area to create a pocket. The vagus nerve is exposed and the electrodes are wrapped around it through the neck incision. The distal ends of the lead are connected to the pulse generator, and latter is then placed in the infraclavicular pocket through the neck incision. RESULTS: Thirty-eight implants were conducted with this technique. The pulse generator could be implanted and anchored to the underlying tissue without any difficulty. Except for wound infections in two patients there was no other complication. CONCLUSION: A single incision is an alternate to the double incision procedure. This procedure can be performed safely.

In vitro fermentation characteristics of native and processed cereal grains and potato starch using ileal chyme from dogs.

Two in vitro experiments were conducted to evaluate the ability of small intestinal bacteria of dogs to ferment native and extruded cereal grains and potato starch and cereal grain and potato flours. Substrates included barley, corn, potato, rice, sorghum, and wheat. In addition to testing native grains and flours, extruded substrates also were tested. Substrates were extruded at low temperatures (LT; 79 to 93 degrees C) and high temperatures (HT; 124 to 140 degrees C) using a Wenger extruder (model TX-52). Substrates varied widely in concentrations of rapidly digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS), and total starch (TS). Extrusion of most substrates at HT vs LT resulted in increased RDS and decreased RS concentrations. Organic matter disappearance (OMD) values attributed to microbial fermentation for a 5-h period were as high as 27% for native extruded substrates (LT potato starch) and 39% for potato flour. Average OMD was higher for cereal and potato flours than for native extruded substrates (29.9 vs 25.4%). Average molar percentages of short-chain fatty acids produced from all substrates fermented for 5 h were 73, 14, and 13% (acetate, propionate, and butyrate, respectively). Average lactate production for substrates ranked as follows: flours > native and extruded cereal grains and potato starch (0.33 and 0.18 mmol/g OM, respectively). In vitro microbial fermentation of starches by ileal bacteria can be substantial and is affected by differences in starch source, fraction, and processed form.

Daleformis, a new phytoalexin from the roots fo Dalea filiciformis: an inhibitor of endothelin converting enzyme.

As part of a search for novel inhibitors of endothelin converting enzyme (ECE), the MeOH-CH2Cl2 extract of the roots of Dalea filiciformis was shown to be active. Bioassay-guided fractionation of the extract yielded a novel phytoalexin, daleformis (1), whose structure was determined by interpretation of spectral data and X-ray analysis. Daleformis (1) inhibited ECE with an IC50 of 9 microM.

Nonresective treatment of pineoblastoma: a case report.

BACKGROUND: Stereotactic biopsy followed by cytoreductive surgery and/or radiation are the standard treatment for pineoblastoma. We are reporting a patient with a relatively large pineoblastoma, who was treated with a combination of nonresective treatment modalities. METHOD: The patient is a 20-year-old woman who presented with signs and symptoms of raised intracranial pressure. Magnetic resonance imaging (MRI) showed a large tumor in the pineal region and hydrocephalus. She was emergently treated by placement of a ventriculoperitoneal shunt. Three days later she underwent a stereotactic biopsy, which showed the tumor to be pineoblastoma. She was then further treated with the following treatment modalities: permanent implantation of high activity I125 seeds, external radiation, and chemotherapy. RESULTS: At 10 months' follow-up, MRI showed complete disappearance of the tumor. At 18 months' follow-up, the patient is asymptomatic, neurologically intact, and her MRI scans show no evidence of intracranial or intraspinal tumor. CONCLUSIONS: Though the follow-up is relatively short, the results of the nonresective approach in this patient have been excellent.

Response of extra-axial tumors to stereotactically implanted high-activity 125I seeds.

125I seeds can deliver a very high dose of radiation (100-500 Gy) to a well-circumscribed area over their average life of 87 days, which enable them to destroy slow-growing extra-axial tumors after permanent implantation. Stereotactic implantation of 125I seeds was performed in 26 patients with extra-axial tumors, with a median follow-up of 32 months. No acute morbidity or mortality resulted from the procedure. Cranial nerve involvement in 5 patients was the only delayed complication. One patient developed radionecrosis outside the range of 125I dose distribution, which was felt to be due to the hyperfractionated external radiation the patient had received prior to 125I seed placement. All 26 patients showed tumor regression. The results indicate that this form of treatment is relatively safe and effective in the management of extra-axial tumors.

Voluntary intake and digestibility by mature beef cattle and Holstein steer calves consuming alfalfa or orchardgrass hay supplemented with soybean oil and(or) corn.

Effects and interactions of corn and soybean oil supplementation and forage source on feed intake and digestibility by mature and growing cattle were determined. Eight mature beef cattle (571 +/- 17 kg initial body weight) were used in two simultaneous 4 x 4 Latin squares. Cattle in each square consumed long-stemmed alfalfa (AL; 16% crude protein, 54% neutral detergent fibre and 6.1% acid detergent lignin) or orchardgrass (OR; 11% crude protein, 71% neutral detergent fibre and 9.4% acid detergent lignin) hay ad libitum for 15 d followed by 6 d of restricted consumption (85% of ad libitum). Supplement treatments were Control, ground corn (C; 0.5% body weight), soybean oil (O; 0.125% body weight), or C + O. Total ad libitum dry matter (DM) intake was greater for AL than for OR (P < 0.05) and with than without C (P < 0.05), and a corn x soybean oil interaction occurred (P = 0.07; 11.8, 14.0, 13.6, 14.2, 8.4, 10.7, 9.3 and 10.3 kg/d); total tract neutral detergent fibre (NDF) digestibility was 66.0, 67.7, 65.8, 68.8, 52.5, 50.6, 55.1 and 59.4% for AL, AL - C, AL - O, AL - C + O, OR, OR - C, OR - O, and OR - C + O, respectively (SE 2.46). Eight Holstein steer calves (83 +/- 5 and 131 +/- 11 kg initial and final body weight, respectively) were subjected to the same dietary treatments, except for higher levels of C (1.0% body weight) and O (0.25% body weight) and periods with 21 d of ad libitum forage intake. Total DM intake was greater (P = 0.06) for AL than for OR, increased (P < 0.05) by C, and decreased (P < 0.05) by O (3.92, 4.17, 3.51, 4.00, 2.53, 2.90, 2.09 and 2.51 kg/d), and total tract NDF digestibility was affected by forage source (P < 0.05) and a corn x soybean oil interaction (P = 0.08; 58.8, 56.9, 60.1, 56.0, 41.9, 44.5, 45.8 and 40.1% for AL, AL - C, AL - O, AL - C + O, OR, OR - C, OR - O and OR - C + O, respectively). In conclusion, effects of supplementation with corn and (or) soybean oil on feed intake and digestibility were similar for AL and OR, which differed in voluntary intake and digestibility, and animal characteristics such as stage of maturity may have influenced effects of soybean oil on feed intake.

Feed intake and digestibility by cattle consuming bermudagrass or orchardgrass hay supplemented with soybean hulls and(or) corn.

Effects of supplementing cattle consuming tropical or temperate grass with corn and (or) soybean hulls on feed intake and digestibility were determined. In Exp. 1, eight Holstein steer calves (210 +/- 9.2 and 269 +/- 9.4 kg initial and final BW, respectively), in two simultaneous Latin squares, were given ad libitum access to bermudagrass (B) or orchardgrass (O) hay without supplementation or with (DM basis) .5% of BW of ground corn (C), .7% of BW of soybean hulls (H), or .25% of BW of corn plus .35% of BW of soybean hulls (CH). Total OM intake was greater (P < .05) with than without supplementation (5.05, 6.04, 5.95, 6.06, 6.04, 6.81, 6.61, and 6.69 kg/d), and digestible OM intake was affected by forage source (P < .05), mixing of supplement types (CH versus the mean of C and H; P < .09), and the forage source x supplementation interaction (P < .09; 2.65, 3.40, 3.33, 3.46, 3.71, 4.14, 3.98, and 4.30 kg/d for B, B-C, B-H, B-CH, O, O-C, O-H, and O-CH, respectively). Total tract NDF digestibility was greater (P < .05) for O than for B diets and for H than for C (56.4, 53.9, 58.1, 56.9, 68.5, 64.9, 67.7, and 69.6% for B, B-C, B-H, B-CH, O, O-C, O-H, and O-CH, respectively). In Exp. 2, mature cannulated beef cattle (524 +/- 1.6 kg BW) were used in a design similar to Exp. 1 with comparable dietary supplement levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of supplementing growing steers with high levels of partially hydrogenated tallow on feed intake, digestibility, live weight gain, and carcass characteristics.

Effects of supplementing growing steers consuming forage-based diets with high levels of partially hydrogenated tallow on feed intake, digestibility, live weight gain, and carcass characteristics were determined in this study. In Exp. 1, Holstein steer calves were fed bermudagrass hay alone (Control) and with a ground corn-based concentrate at .95% BW (DM basis) plus partially hydrogenated tallow at 0 (Basal), .33 (low fat; LF), or .67% BW (high fat; HF) in a Latin square. Total DMI was increased by concentrate supplementation and was lower for HF than for LF (P < .05; 3.18, 3.83, 4.25, and 3.17 kg/d for Control, Basal, LF, and HF, respectively). In Exp. 2, grazing Angus x Hereford steers (270 kg +/- .4 initial shrunk BW) were fed the same supplements as in Exp. 1 for 84 or 98 d and slaughtered. Live weight gain was increased (P < .05) by concentrate supplementation (1.01, 1.34, 1.41, and 1.30 kg/d for Control, Basal, Low, and High, respectively). The concentration of total lipids in longissimus muscle was 2.51, 2.53, 3.05, and 3.03% of wet tissue for Control, Basal, LF, and HF, respectively (Basal > the mean of LF and HF; P < .07); the proportion of palmitic acid in total fatty acids was similar among treatments. Fat supplementation did not markedly affect sensory, taste, or tenderness characteristics of longissimus muscle. In conclusion, supplementing grazing beef steers with high levels of partially hydrogenated tallow, with slaughter at approximately 400-kg shrunk BW, tended to increase fat in longissimus muscle without altering the palmitic acid level in fatty acids, although sensory, taste, and tenderness characteristics were not modified.

A screen for inhibitors of DNA recombination: identification of two new spirostanol glycosides from Chamaedorea linearis.

Two new glycosides have been isolated from the MeOH extract of the stem wood and stem bark of an Ecuadorian plant Chamaedorea linearis, and their structures have been determined by spectroscopic means and X-ray analysis of the aglycone to be 1-O-[beta-L-fucopyranosyl-(4'-sulfate)]-25R,5 alpha-spirostane-1 beta, 3 beta-diol [1]) and 1-O-[beta-L-fucopyranosyl-(4'-sulfate)]-25R,5 alpha-spirostane-1 alpha, 3 beta-diol [2]. These compounds were identified in a screen for inhibitors of recombinational DNA repair. Cytotoxic activity was also demonstrated.

Effects of various supplements on voluntary intake and performance by growing cattle consuming forage moderate to high in crude protein.

Growing cattle were supplemented with substances to lessen or increase ruminal ammonia level to determine if consumption of moderate- to high-crude protein (CP) forage is limited by high ruminal ammonia absorption. In Experiment 1 (5 x 5 Latin square), five Holstein steers (198 kg) had ad libitum access to alfalfa cubes (17% CP) without supplementation or with corn at 0.25 or 0.75% body weight (BW) alone (LC or HC) or with 0.06% BW of zeolite (chabazite; LC-Z and HC-Z). Total daily organic water (OM) intake was not affected by treatment (6.08, 6.14, 6.11, 6.19 and 6.09 kg for control, LC, LC-Z, HC and HC-Z, respectively; SE 0.25). In Experiment 2, Simmental crossbred beef calves grazed fescue-clover paddocks in the spring (clipped forage: 21 to 27% CP) for 84 days and were supplemented with 0.25 or 0.75% BW corn alone or with added zeolite (0.06% BW) or lasalocid (0.5 mg/kg BW). Daily gain did not differ among treatments (1.24 to 1.31 kg/day). In Experiment 3 (6 x 6 Latin square), six Holstein steer calves (168 kg) had ad libitum access to medium-quality, orchardgrass-clover hay (15% CP). Steers received one of the following six treatments: no supplement (Control), 0.35% BW ground corn (C), corn plus 0.049% BW urea (C-U), 0.35% BW soybean meal (S), 0.205% BW feather meal (F) or 0.103% BW feather meal, 0.052% BW blood meal and 0.067% BW corn gluten meal (F-BG). Total daily OM intake was 5.00, 5.14, 5.00, 5.11, 4.84 and 4.70 kg for control, C, C-U, S, F and F-BG, respectively (SE 0.13). In Experiment 4 (6 x 6 Latin square), six Holstein steer calves (226 kg) were fed 0.75% BW of alfalfa cubes (19% CP) plus ad libitum access to medium- to high-quality orchardgrass hay (16% CP). Steers received one of the following six treatments: no supplement (Control), corn at 0.25% BW alone (c) or mixed with 0.12% BW peanut skins (C-PSK), a mix of high-CP feedstuffs high in ruminal escape protein (0.029% BW blood meal, 0.038% BW corn gluten meal and 0.028% BW feather meal; C-REP), 0.139% soybean meal (C-S) or soybean meal plus peanut skins (C-PSK-S). Total daily OM intake was 6.16, 6.25, 6.13, 6.52, 6.50 and 6.60 kg for control, C, C-PSK, C-REP, C-S and C-PSK-S, respectively (SE 0.10).(ABSTRACT TRUNCATED AT 400 WORDS)

Continuous low dose rate brachytherapy with high activity iodine-125 seeds in the management of meningiomas.

The purpose of this study was to evaluate if meningiomas can be effectively treated with brachytherapy using permanent implantation of high activity I-125 seeds. Thirteen patients with intracranial meningiomas were treated by means of permanent stereotactic implantation of one or more high-activity I-125 seeds. The physical characteristics of I-125 enabled us to deliver a minimum tumor dose ranging from 100 Gy to 500 Gy at a low dose rate of 5 cGy to 25 cGy per hr. Indications for this procedure included recurrence after initial surgery or as primary modality of treatment in patients who were not candidates for surgery. All 13 patients are alive at a median follow-up of 25 months. Nine of 13 patients achieved complete resolution of the tumor and in the remaining four, more than 50% reduction in tumor volume was noted at the last follow-up. No late complications were observed. We conclude from this initial data that localized high dose irradiation delivered at a low dose rate using I-125 permanent implantation is an effective, safe, and simple method in the treatment of both recurrent and primary intracranial meningiomas.

Thermal profiles of electrocauteries, the Nd:YAG laser, and the electromagnetic-field focusing system.

Electromagnetic-field focusing (EFF) is a method of converging induced eddy current onto a pointed tip of a tuned length return circuit in the near field of a resonator, which results in the production of high temperature. Previously reported applications of this method include various devices for local hyperthermia and a precision surgical device. The latter is currently being used in human clinical trials under two investigational device exemptions from the Food and Drug Administration. In the present work, the thermal profile produced in a uniform, tissue-simulating phantom by the hand-held probe of the surgical EFF system is compared with those produced by mono- and bipolar electrocauteries and by a contact Nd:YAG laser. At the equivalent power setting and 2-cm insertion depth, the EFF probe was shown to have a tighter thermal profile than the monopolar electrocautery or the contact Nd:YAG laser. This finding is consistent with earlier histologic evidence that brain cortical tissue cut by the surgical EFF probe had minimal thermal damage in the tissue surrounding the incision.