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[Extended supra glottic laryngectomies].

In the period 1976-1998, 408 patients with supraglottic laryngeal cancer were primarily treated by surgery using the method of supraglottic laryngectomy. Classical supraglottic laryngectomy was performed in 355 patients, while 53 underwent extended supraglottic laryngectomy. The objective of the study was to analyze the success of the extended supraglottic laryngectomy in relation to classical supraglottic laryngectomy in indicated cases. T1 tumor was found in 171 (42%) patients, T2 in 212 (52%), while T3 was found in 25 (6%) cases. Local recurrence developed in 3 out of 53 patients operated by the extended supraglottic laryngectomy technique, and in 17 out of 355 operated by classical supraglottic laryngectomy (chi2=0.075, DF=1, p=0.784; Yates=0.00, p=1.00). Five-year survival of patients operated by the extended supraglottic laryngectomy was reported in 40 out of 53 patients, while survival of patients operated by classical supraglottic laryngectomy was noted in 270 out of 355 cases (chi2=0.004, DF=1, p=0.926; Yates=0.00, p=1.00). There was no significant difference of local recurrence and five-year survival between patients treated by classical and extended supraglottic laryngectomy.

Carcinoma, Squamous Cell↗

Tissue and plasma concentrations of amidated and glycine-extended glucagon-like peptide I in humans.

Using specific radioimmunoassays, we studied the occurrence of amidated and glycine-extended glucagon-like peptide I (GLP-I) molecules in the human small intestine and pancreas and in the circulation system in response to a breakfast meal. Through gel permeation chromatography of extracts of the human pancreas (n = 5), we found that 71% of the GLP-I immunoreactivity eluted as a large molecule corresponding to the major proglucagon fragment, 24% corresponded to GLP-I 1-36 amide, and 5% to GLP-I 1-37. By gel permeation chromatography of extracts of human small intestine (n = 6), we found that all immunoreactivity eluted in one peak at the common elution position of the two insulin-releasing peptides, GLP-I 7-36 amide and GLP-I 7-37. Of the GLP-I immunoreactivity, 80% corresponded to GLP-I 7-36 amide and 20% to GLP-I 7-37. The mean concentrations of amidated GLP-I and glycine-extended GLP-I in fasting plasma were 7 +/- 1 and 6 +/- 1 pM, respectively (n = 6). In response to a breakfast meal, the concentration of amidated GLP-I rose significantly amounting to 41 +/- 5 pM 90 min after the meal ingestion, whereas the concentration of glycine-extended GLP-I only rose slightly to a maximum of 10 +/- 1 pM. Thus, both amidated and glycine-extended GLP-I molecules are produced in the small intestine and in the pancreas in humans. Both amidated and glycine-extended GLP-I are measurable in fasting plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Evaluation of the bioavailability and pharmacokinetics of two extended-release theophylline formulations in dogs.

OBJECTIVE: To evaluate the bioavailability and pharmacokinetic characteristics of 2 commercially available extended-release theophylline formulations in dogs. DESIGN: Randomized 3-way crossover study. ANIMALS: 6 healthy adult dogs. PROCEDURE: A single dose of aminophylline (11 mg x kg(-1) 15 mg x lb(-1)], i.v., equivalent to 8.6 mg of theophylline/kg 13.9 mg x lb(-1) or extended-release theophylline tablets (mean dose, 15.5 mg x kg(-1) [7.04 mg x lb9-1), PO) or capsules (mean dose, 15.45 mg x kg(-1) [7.02 mg x lb(-1)], PO) was administered to all dogs. Blood samples were obtained at various times for 36 hours after dosing; plasma was separated and immediately frozen. Plasma samples were analyzed by use of fluorescence polarization immunoassay. RESULTS: Administration of theophylline i.v. best fit a 2-compartment model with rapid distribution followed by slow elimination. Administration of extended-release theophylline tablets and capsules best fit a 1-compartment model with an absorption phase. Mean values for plasma terminal half-life, volume of distribution, and systemic clearance were 8.4 hours, 0.546 L x kg(-1), and 0.780 mL x kg(-1) x min(1), respectively, after i.v. administration of theophylline. Systemic availability was > 80% for both oral formulations. Computer simulations predicted that extended-release theophylline tablets or capsules administered at a dosage of 10 mg x kg(-1) (4.5 mg x lb(-1)), PO, every 12 hours would maintain plasma concentrations within the desired therapeutic range of 10 to 20 microg x mL(-10. CONCLUSIONS AND CLINICAL RELEVANCE: Results of these single-dose studies indicated that administration of the specific brand of extended-release theophylline tablets or capsules used in this study at a dosage of 10 mg x kg(-1), PO, every 12 hours would maintain plasma concentrations within the desired therapeutic range (10 to 20 microg x mL(-1)) in healthy dogs.

Administration, Oral↗

Influence of cooling rates and extenders upon post-thaw viability of bovine spermatozoa packaged in .25- and .5-ml French straws.

Post-thaw survival of bovine spermatozoa was compared for semen packaged in either .25- or .5-ml French straws and frozen at three different cooling rates in moving N2 vapor. Using a split ejaculate technique, nine ejaculates were extended in heated skim milk, egg yolk-citrate and egg yolk-Tris and packaged in .25- and .5-ml French straws. Semen packaged in the .25- and .5-ml straws was frozen simultaneously at initial N2 vapor temperatures of -140, -110 or -80 C. Semen was thawed in a water bath at 35 C for 1 min. Recovery of spermatozoa was evaluated immediately post-thaw (0 h) and again after 3 h of incubation at 37 C. Motility estimates and motility counts were made using phase contrast microscopy; percentage of spermatozoa possessing intact acrosomes was quantitated using differential interference contrast microscopy. There was a packaging unit X cooling rate interaction (P less than .05) for all three viability measures. However, there was no consistent trend with regard to cooling rate or packaging unit among the three extenders examined. Post-thaw viability for each characteristic varied (P less than .01) among extenders, but not for cooling rate or packaging unit (P greater than .05). Spermatozoa extended and frozen in egg yolk-Tris had greater (P less than .05) post-thaw viability than those extended in skim milk or egg yolk-citrate regardless of cooling rate or volume of the seminal package.

Acrosome↗

Evaluation of extended-release applications for solid dispersion hot-melt fluid bed coatings utilizing hydrophobic coating agents.

A new hot-melt fluid bed coating method was evaluated for potential extended-release applications. Chlorpheniramine maleate (CPM) USP was chosen as a model drug. The assays for drug release and content uniformity were dictated by the USP Official Monograph for a Chlorpheniramine Maleate Extended-Release Capsule. The fluid bed chamber was charged with CPM-loaded nonpareils and hydrophobic coating agents in the solid state. The method consists of four processing stages: (a) warming, (b) preheating, (c) melting-spreading, and (d) cooling-congealing. Various hydrophobic coating agent candidates were evaluated for extended-release potential by a preliminary screen at a coating agent level of 1.5% (w/w). A beeswax coating agent was identified as the most promising candidate of the preliminary screen. After the level of beeswax was increased to 2.0%, the dissolution profile met all of the specifications of the USP Drug Release Test 1 for a CPM Extended-Release Capsule. The potency and content uniformity remained unchanged by the process. Dual coatings demonstrated a cumulative extension of release superior to the capability of a single coat. The new method is a viable alternative to hot-melt spray-coating methodologies. Organic solvents, spraying equipment, steam jackets, and/or heating tape are eliminated from the process. A reduction of equipment costs, setup time, and cleanup time may be realized. The method has demonstrated extended-release capabilities. No excessive attrition of potency or content uniformity has been noted. Additive, multiple coatings that have a cumulative effect on release retardation are feasible.

Evaluation Studies as Topic↗

Pharmacokinetics of extended relief vs regular release Tylenol in simulated human overdose.

BACKGROUND: The purpose of this trial was to compare the pharmacokinetics of the two available acetaminophen dosage forms in simulated human overdose. METHODS: Ten healthy volunteers received acetaminophen, 75 mg/kg orally, either as the regular release or extended relief formulation in a random, crossover fashion. Blood samples were analyzed using a TDx assay and a best fit correlation of data points was determined by PCNONLIN. RESULTS: The area under the curves for extended relief acetaminophen and regular release acetaminophen were 426 mg h/L and 432 mg h/L, respectively (p = 0.768). The mean half times for extended relief acetaminophen and regular release acetaminophen were 4.02 h and 2.56 h, respectively (p < 0.001). The mean maximum serum acetaminophen concentrations were 62.6 mg/L (414.4 mmol/L:) and 94.3 mg/L (624.3 mmol/L) for extended relief acetaminophen and regular release acetaminophen, respectively (p < 0.001) and the mean time to maximum serum acetaminophen concentrations were 0.87 h and 0.75 h for extended relief acetaminophen and regular release acetaminophen, respectively (p = 0.508). CONCLUSIONS: Although the formulations appear to have equal bioavailability, their half-lives and peak concentrations were significantly different. Further study is required to determine whether these differences affect the assessment and management of poisoned patients.

Acetaminophen↗

Modeling extended lactations of dairy cows.

Nine mathematical models were compared for their ability to predict daily milk yields (n = 294,986) in standard 305-d and extended lactations of dairy cows of Costa Rica. Lactations were classified by parity (first and later), lactation length (9 to 10, 11 to 12, 13 to 14, 15 to 16, and 16 to 17 mo), and calving to conception interval (1 to 2, 3 to 4, 5 to 6, 7 to 8, and 9 to 10 mo). Of the nine models, the diphasic model and lactation persistency model resulted in the best goodness of fit as measured by adjusted coefficient of determination, residual standard deviation, and Durbin-Watson coefficient. All other models showed less accuracy and positively correlated residuals. In extended lactations, models were also fitted using only test-day records before 305 d, which resulted in a different ranking. The diphasic model showed the best prediction of milk yield in standard and extended lactations. We concluded that the diphasic model provided accurate estimates of milk yield for standard and extended lactations. Interpretation of parameters deserves further attention because of the large variation observed. As expected, the calving to conception interval was found to have a negative effect on milk yield for cows with a standard lactation length. In extended lactations, these negative effects of pregnancy on milk yield were not observed.

Animals↗

Straw-thawing method interacts with sire and extender to influence sperm motility and conception rates of dairy cows.

Influence of interactions of straw-thawing method with sire and extender type (milk or egg yolk-based) on postthaw sperm motility and conception rates of dairy cows was assessed. In experiment 1, sperm from 10 Holstein sires were frozen in egg yolk citrate and heated whole-milk extenders using a split-ejaculate technique. Straws were thawed in a 37 degrees C water bath with or without 3 min of exposure to a 37 degrees C warming plate while wrapped in a paper towel (air-thaw). Percentage of motile sperm was assessed after 1 min and 3 h of incubation at 37 degrees C. In experiment 2, sperm from 3 Holstein sires were frozen in egg-yolk citrate and a nonheated whole milk extender using a split-ejaculate technique. Straws were thawed and motility was assessed as in experiment 1. Conception rates (n = 475) were compared in a single herd of Holstein cows after thawing straws in 35 degrees C water for 45 s or after air-thawing by wiping straws with a paper towel upon removal from the storage vessel and placing directly into the insemination gun. In each experiment, interactions between thaw method and sire, extender type, or both, indicated that conditions may be created that facilitate sperm tolerance of air-thaw procedures. When a significant thaw method effect was detected in either experiment, air-thaw was consistently associated with the lesser measure of sperm motility, conception, or both. In conclusion, although some sire x extender combinations seem to be tolerant of air-thaw procedures, other combinations are more sensitive, resulting in reduced postthaw sperm survival, conception rates of cows, or both, in response to air-thaw.

Animals↗

Lipid deficient extender for bovine spermatozoa: its development and use in measuring freezing-induced lipid loss.

To facilitate the measurement of lipid losses from spermatozoa due to freezing, three low-lipid seminal extenders containing lactose, bovine serum albumin, or soybean protein were evaluated as potential cryoprotectants. All extenders were formulated to have an osmotic pressure within the range of 270 to 330 mosmol and a pH of 6.8 to 7.0. Soybean protein (Promine-D) maintained the highest post-thaw motility of spermatozoa with similar survival for spermatozoa frozen in ampules and straws. The extender derived from testing several components consisted of Tris(hydroxymethyl) aminomethane (245 mM), and citric acid monohydrate (78mM), as the buffering compounds; and fructose (69 mM), glycerol (7% vol/vol), and Promine-D (1.5% wt/vol). Post-thaw sperm motility of approximately 40% was not different from the Tris-egg yolk control. Fertility of fresh rabbit semen treated with the extender was normal. After freeze-thawing, protected spermatozoa contained more lipid (1.61 versus 1.20 mug/10-6 sperm) and lost less glutamic oxaloacetic transaminase enzyme (102 versus 108 Karmen units) than when Promine-D was not incorporated. However, even with protection by soybean protein, spermatozoa lipid content decreased from 2.43 to 1.61 mug/10-6 sperm after one freeze-thawing. The lipid status of spermatozoa frozen and thawed in conventional bull seminal extenders containing large amounts of lipids is unknown.

Animals↗

Fertility of bull sperm frozen and stored in clarified egg yolk-Tris-glycerol extender.

Egg yolk-Tris-glycerol extender, which is widely used in commercial artificial insemination (AI), was modified by replacing the 20% egg yolk (vol/vol) with a supernatant from egg yolk centrifuged at 50,000 x g for 2 h and then used to cryopreserve bull sperm. Preliminary studies showed that 20% egg yolk interfered with biochemical assays, which could be overcome by centrifugation. In Experiment 1, semen from 4 Holstein bulls was frozen in the experimental Tris extender and compared with the whole milk-glycerol control. A total of 2256 first services resulted in 72.6% 60- to 90-d nonreturns for the control and 71.0% for the Tris extender. In Experiment 2, semen from 10 Holstein bulls was frozen in the experimental Tris extender. Half of the semen was used immediately and half was stored in liquid nitrogen for 1 yr before distribution. The nonreturn rates based on 8878 first services for 7 bulls that completed both parts of the trial were 70.9% initially and 71.6% 1 yr later. This time trend difference of 0.7% was comparable to 0.6% for the AI mean for Holstein sires used at the same time. These fertility results and previous laboratory studies indicate that the conventional egg yolk-Tris-glycerol might be simplified for cryopreserving bull sperm. The experimental Tris extender also was suitable for making biochemical measurements.

Animals↗

Beltsville poultry semen extender. 7. Comparison of commercial diluents for holding turkey semen six hours at 15 C.

The ability of three commercial semen diluents (Minnesota, I.M.V.-French and Universal) and the Beltsville Poultry Semen Extender (BPSE) to maintain the fertilizing capacity of turkey semen held 6 hr at 15 C was examined. Hens were inseminated weekly for 20 wk and hatchability of eggs was determined. Neither candling nor true fertility of semen diluted 1:1 in BPSE, the Minnesota, or I.M.V.-French diluent and held for 6 hr differed significantly from each other. Fertility of semen held 6 hr in BPSE or Universal diluent was lower than their respective unstored controls. No difference in fertility was observed between semen held in Minnesota or I.M.V.-French diluent and their unstored controls. Significantly higher hatch of fertile eggs and of all eggs set was obtained from hens inseminated with semen diluted (0 hr) with BPSE (90 and 86%) than all other diluents. Hatch of fertile eggs was higher from hens inseminated with semen held 6 hr in Universal (90%) and French (86%) extenders and lower for the Minnesota (78%) extender. No difference was observed in hatch of fertile eggs between the BPSE (84%) and French (86%) extender. Hatchability of all eggs set was higher when hens were inseminated with semen held 6 hr in the I.M.V.-French diluent (81%) when compared to hens inseminated with the Minnesota (75%) or Universal diluent (75%). No differences in hatch of all eggs set were noted when BPSE (77%) and the commercial extenders were compared.

Animals↗

Effects of prefreeze treatments on the fertilizing capacity of unfrozen and frozen chicken semen: extender characteristics and dilution method.

The object of this study was to evaluate the effects of extender osmotic pressure (251, 332, and 434 mOsm), extender pH (6.5, 7.0, and 7.5), extender fructose concentration (0, 2.5, 5, and 10 g/liter), and diluting prior to freezing to a constant sperm number (.5, .8, 1, or 2 X 10(9) sperm/ml) on the fertilizing capacity of processed-unfrozen and frozen-thawed chicken spermatozoa. Fertilizing capacity of processed-unfrozen spermatozoa was not affected by changes in extender osmotic pressure, pH, or fructose concentration; it was significantly depressed, Days 2 to 4 postinsemination, by diluting to 5 X 10(9) sperm cells/ml, whereas all other dilution rates had little effect. Fertilizing capacity of frozen-thawed spermatozoa was highest (42 to 51%, Days 2 to 4 postinsemination) when diluted in an extender containing 5g/liter of fructose with an osmotic pressure of 332 mOsm and a pH of either 7.0 or 7.5. Fertility (51%, 2 to 4 days after insemination) obtained with frozen-thawed semen diluted to 1 X 10(9) sperm cells/ml was significantly higher than all other dilutions. The fertilizing capacity of frozen-thawed spermatozoa was generally lower than that of processed-unfrozen spermatozoa regardless of the experimental treatment.

Animals↗

Prospective, randomized, double-blind study of the efficacy and tolerability of the extended-release formulations of oxybutynin and tolterodine for overactive bladder: results of the OPERA trial.

OBJECTIVE: To compare the efficacy and tolerability of extended-release formulations of oxybutynin chloride and tolterodine tartrate in women with overactive bladder. PATIENTS AND METHODS: The OPERA (Overactive bladder: Performance of Extended Release Agents) trial was a randomized, double-blind, active-control study performed at 71 US study centers from November 21, 2000, to October 18,2001. Extended-release formulations of oxybutynin at 10 mg/d or tolterodine at 4 mg/d were given for 12 weeks to women with 21 to 60 urge urinary incontinence (UUI) episodes per week and an average of 10 or more voids per 24 hours. Episodes of UUI (primary end point), total (urge and nonurge) incontinence, and micturition were recorded in 24-hour urinary diaries at baseline and at weeks 2, 4, 8, and 12 and compared. Adverse events were also evaluated. RESULTS: Improvements in weekly UUI episodes were similar for the 790 women who received extended-release formulations of oxybutynin (n = 391) or tolterodine (n = 399). Oxybutynin was significantly more effective than tolterodine in reducing micturition frequency (P = .003), and 23.0% of women taking oxybutynin reported no episodes of urinary incontinence compared with 16.8% of women taking tolterodine (P = .03). Dry mouth, usually mild, was more common with oxybutynin (P = .02). Adverse events were generally mild and occurred at low rates, with both groups having similar discontinuation of treatment due to adverse events. CONCLUSIONS: Reductions in weekly UUI and total incontinence episodes were similar with extended-release formulations of oxybutynin and tolterodine. In the oxybutynin group, micturition frequency was significantly lower, and the percentage of women reporting no urinary incontinence episodes was significantly higher compared with the tolterodine group. Dry mouth was more common with oxybutynin, but tolerability was otherwise comparable, including adverse events involving the central nervous system.

Administration, Oral↗

Feasibility of using half-life multipliers to estimate extended withdrawal intervals following the extralabel use of drugs in food-producing animals.

Under the Animal Medicinal Drug Use Clarification Act of 1994, veterinarians are legally allowed to use drugs in food-producing animals in an extralabel manner. This could potentially lead to violative residues in food of animal origin. It is therefore essential that an appropriately extended withdrawal interval be established. Ideally, these extended withdrawal intervals should be calculated on the basis of the tissue half-life of the drug in the target animal. However, these data are not readily available for all drugs of extralabel use in food-producing animals. For this reason, the use of a half-life multiplier has been proposed as a simple alternative method to estimate the effective tissue half-life of a drug. Extended withdrawal intervals, estimated using various half-life multipliers, were compared with the withdrawal intervals calculated using actual tissue half-lives. For the group of drugs investigated, a half-life multiplier of 5 resulted in estimates of extended withdrawal intervals that were potentially inadequate to prevent violative tissue residues for drugs that had relatively long tissue half-lives, high tolerances, or both. This is possibly because fewer half-lives are required for these drugs to reach the target tissue concentrations following administration at label doses. Use of a smaller half-life multiplier (in this case 3) is therefore suggested to ensure that extended withdrawal intervals are adequate to prevent violative tissue residues.

Algorithms↗

Ardeparin sodium for extended out-of-hospital prophylaxis against venous thromboembolism after total hip or knee replacement. A randomized, double-blind, placebo-controlled trial.

BACKGROUND: The optimal duration of prophylaxis against venous thromboembolism after total hip or knee replacement is uncertain. OBJECTIVE: To determine the efficacy and safety of extended out-of-hospital prophylaxis with low-molecular-weight heparin (ardeparin sodium). DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: 33 community, university, or university-affiliated hospitals. PATIENTS: 1195 adults who had elective total hip or knee replacement and completed 4 to 10 days of postoperative ardeparin prophylaxis. INTERVENTION: Daily subcutaneous ardeparin (100 anti-Xa IU/kg of body weight) or placebo from time of hospital discharge to 6 weeks after surgery. MEASUREMENTS: Symptomatic, objectively documented venous thromboembolism or death, along with major bleeding, from time of hospital discharge to 12 weeks after surgery. RESULTS: Patients who received ardeparin (n = 607) and those who received placebo (n = 588) did not differ significantly in the cumulative incidence of venous thromboembolism or death (9 cases [1.5%] compared with 12 cases [2.0%]; odds ratio, 0.7 [95% CI, 0.3 to 1.7]; P > 0.2; absolute difference, -0.56 percentage points [CI, -2.2 to 1.1 percentage points]) or major bleeding (2 cases [0.3%] compared with 3 cases [0.5%]). CONCLUSIONS: Among patients who had total knee or total hip replacement and received 4 to 10 days of postoperative ardeparin prophylaxis, the cumulative incidence of symptomatic venous thromboembolism or death after hospital discharge was not significantly reduced by extended out-of-hospital ardeparin prophylaxis. Extended ardeparin use could provide a maximum 2.2-percentage point true reduction in such events. The benefit of extended ardeparin use is not clinically important for most patients. Future research should identify high-risk patients who would benefit most from extended prophylaxis.

Adult↗

Extended out-of-hospital low-molecular-weight heparin prophylaxis against deep venous thrombosis in patients after elective hip arthroplasty: a systematic review.

PURPOSE: Evidence-based medicine guidelines based on venographic end points recommend in-hospital prophylaxis with low-molecular-weight heparin (LMWH) in patients having elective hip surgery. Emerging data suggest that out-of-hospital use may offer additional protection; however, uncertainty remains about the risk-benefit ratio. To provide clinicians with a practical pathway for translating clinical research into practice, we systematically reviewed trials comparing extended out-of-hospital LMWH prophylaxis versus placebo. DATA SOURCES: Studies were identified by 1) searching PubMed, MEDLINE, and the Cochrane Library Database for reports published from January 1976 to May 2001; 2) reviewing references from retrieved articles; 3) scanning abstracts from conference proceedings; and 4) contacting pharmaceutical companies and investigators of the original reports. STUDY SELECTION: Randomized, controlled trials comparing extended out-of-hospital prophylaxis with LMWH versus placebo in patients having elective hip arthroplasty. DATA EXTRACTION: Two reviewers extracted data independently. Reviewers evaluated study quality by using a validated four-item instrument. DATA SYNTHESIS: Six of seven original articles met the defined inclusion criteria. The included studies were double-blind trials that used proper randomization procedures. Compared with placebo, extended out-of-hospital prophylaxis decreased the frequency of all episodes of deep venous thrombosis (placebo rate, 150 of 666 patients [22.5%]; relative risk, 0.41 [95% CI, 0.32 to 0.54; P < 0.001]), proximal venous thrombosis (placebo rate, 76 of 678 patients [11.2%]; relative risk, 0.31 [CI, 0.20 to 0.47; P < 0.001]), and symptomatic venous thromboembolism (placebo rate, 36 of 862 patients [4.2%]; relative risk, 0.36 [CI, 0.20 to 0.67; P = 0.001]). Major bleeding was rare, occurring in only one patient in the placebo group. CONCLUSIONS: Extended LMWH prophylaxis showed consistent effectiveness and safety in the trials (regardless of study variations in clinical practice and length of hospital stay) for venographic deep venous thrombosis and symptomatic venous thromboembolism. The aggregate findings support the need for extended out-of-hospital prophylaxis in patients undergoing hip arthroplasty surgery.

Aftercare↗

Extended field-of-view sonography: utility in clinical practice.

The purpose of this study was to evaluate the usefulness of real-time extended field-of view sonography in clinical practice (i.e., the frequency of use in various body systems, the frequency of use by different sonographers, and the benefits and drawbacks in comparison to conventional real-time sonography). The use of extended field-of-view sonography was monitored for a 6 month period. The pattern of usage among different sonographers and for different body systems was documented. Extended field-of-view sonography was utilized in 26.5% of patients. In comparison, color Doppler sonography was used in 23.2% of patients. Utilization of extended field-of-view sonography varied significantly among sonographers and among different body systems. Extended field-of-view sonography allowed measurement of large structures and revealed the anatomic context of abnormalities in circumstances under which conventional real-time scans could not provide this information.

Computer Systems↗

Enlarged lymph nodes of the neck: evaluation with parallel extended field-of-view sonographic sequences.

A standardized extended field-of-view sonographic examination technique of the neck is evaluated. In a prospective study we screened 50 patients suspected of having carcinoma or lymphoma for enlarged cervical lymph nodes. After conventional CT of the neck, extended field-of-view sonography was performed using defined axial parallel scanning sequences. The results were interpreted separately by two radiologists. Of 245 lymph nodes (diameter 1 cm or greater) diagnosed with conventional CT, 218 were correctly identified by extended field-of-view ultrasonography. With respect to the entire neck, the sensitivity of extended field-of-view sonography was 92%, and the correlation coefficient between the methods was r = 0.98 (P < 0.001). Fifteen of 17 false-negative lymph nodes were located in the mandibular angle region. False-positive results (N = 10) were caused by misinterpretation of primary tumors, blood vessels, lobulated salivary glands, and double imaged lymph nodes. Our results indicate that extended field-of-view sonography in parallel scanning sequences represents a reliable method for the detection of cervical lymphadenopathy.

Adult↗