Initial evaluation of a continuous speech recognition program for radiology

The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.     

Objective Pulse-Synchronous "Essential" Tinnitus due to Narrowing of the Transverse Dural Venous Sinus

Subjective tinnitus is a common problem with many etiologies. Objective tinnitus, in which the sound is perceived by both the patient and the examiner, is less common. Objective tinnitus of the vascular type, in which a pulse synchronous bruit is heard by an independent observer, is frequently related to an underlying arterial or arteriovenous malformation, most commonly a dural arteriovenous fistula (DAVF) involving the transverse and sigmoid sinuses. The remaining cases are usually termed "essential" vascular tinnitus, and are presumed to have a venous etiology. In these cases, the audible noise is generally assumed to be produced within the sino-jugular connection, or within an enlarged jugular bulb. We present four documented cases of objective pulse synchronous tinnitus due to focal narrowing (acquired and developmental) of the mid-portion of the transverse dural sinus. In all cases, a bruit was audible directly over a focal constriction in the sinus, demonstrated by cerebral angiography or direct catheter venography. In one case, selective venography revealed a distensible sinus narrowing, associated with a jet of contrast marking fast flow within a developmental sinus segmentation. In another case, a loud pulse synchronous bruit was heard directly over a focal transverse sinus stenosis, which was detected by angiography at the site of a vascular surgical clip. In this case, magnetic resonance (MR) falsely predicted sinus occlusion. In two other cases, an audible bruit was also heard directly overlying a narrowed transverse sinus, seen in the venous phase of angiography. Transverse sinus stenosis is an unappreciated cause of objective pulsatile tinnitus, and we believe that this mechanism may underlie many cases of "essential" or venous etiology tinnitus not otherwise anatomically explained. Non-invasive testing, computed tomography (CT) and MR and non-directed angiography may overlook it. Conventional catheter arteriography or venography should be performed in such cases, with attention to the dural sinuses, if other tests fail to define the anatomic basis of the audible bruit.     

Actigraphically recorded motor activity and immobility across sleep cycles and stages in healthy male subjects

The aim of this study was to compare the extent to which activity and immobility measures are related to sleep stages and sleep cycles in order to improve the informative value of actigraphic assessment of sleep. We therefore performed simultaneous ambulatory polysomnography and wrist-activity monitoring (AM) in 14 healthy male subjects without sleep complaints. In this context, a simple method for transforming raw motor activity data into a time-series reflecting onset and duration of activity and immobility clusters is introduced. Our results demonstrate that nocturnal AM measures were significantly affected by sleep stage. Low activity levels and particularly prolonged episodes of uninterrupted immobility were associated with increasing sleep depth. On the other hand, high activity levels and prolonged episodes of activity were related to intermittent wakefulness during sleep. Our results suggest that measures reflecting the occurrence and duration of activity and immobility clusters provide a better approach in studying the relationship between activity/immobility and sleep stages. Except for the duration of uninterrupted immobility episodes, which showed a significant decrease in the fourth cycle, none of the AM measures showed a significant cycle-to-cycle variation. Consequently, mean nocturnal motor activity measures provide an accurate reflection of the total sleep period. However, none of the AM-derived measures seems useful in evaluating the cycle structure during sleep.     

Efficacy,duration, and absorption of a paediatric oral liquid preparation of ranitidine hydrochloride

The objectives of this study were to assess the clinical efficacy of a new oral ranitidine liquid preparation in reducing gastric acidity and volume, to determine the degree of absorption of the drug, and to determine the duration of drug effect. Eighty preoperative children between the ages of one and six years were enrolled in each of three centres. Each subject was allocated to one of the following groups: Group A - apple juice, 5 ml.kg-1 plus placebo liquid; Group B - apple juice, 5 ml.kg-1 plus ranitidine hydrochloride 2 mg.kg-1; Group C - water, 5 ml and placebo liquid; or Group D - water, 5 ml and ranitidine liquid 2 mg.kg-1. All study agents were administered at least two hours before surgery along with a dye marker, sulfobromophthalein 1 ml (50 mg.ml-1). Following induction of anaesthesia, gastric fluid was aspirated, and analyzed for pH, volume, and sulfobromophthalein content (as an index of the ingested fluids). A serum sample was also drawn and analyzed for ranitidine content by high performance liquid chromatography. Groups B and D had fewer subjects with pH below 2.5 and gastric volume > 0.4 ml.kg-1. The duration of reduced volume and acidity was shown to be greatest from two to four hours after drug administration. Thirty-three percent of subjects receiving oral ranitidine, 2 mg.kg-1 hydrochloride as a single dose demonstrated no measurable effect on gastric pH and volume; 28 of those subjects had adequate ranitidine serum levels.     

Involvement of deprivation and environmental lead in neural tube defects: a matched case-control study

OBJECTIVE: To analyse the prevalence of neural tube defects in small geographical areas and seek to explain any spatial variations with reference to environmental lead and deprivation. SETTING: The Fylde of Lancashire in the north west of England. DESIGN: Cases were ascertained as part of a prospective survey of major congenital malformations in babies born in the Fylde to residents there between 1957 and 1981. A matched case-control analysis used infants with cardiovascular system, alimentary tract, and urinary system malformations as controls. Conditional logistic regression was used to assess the effects of more than 10 micrograms/l lead in drinking water and the Townsend deprivation score. RESULTS: The prevalence of neural tube defects in 1957-73 was higher in Blackpool, Fleetwood, and North Fylde, whereas the three control groups showed no significant spatial variation. In 1957-81 mothers living in electoral wards with either a higher proportion of houses with more than 10 micrograms/l lead in the water or a higher deprivation score had a greater risk of having a baby with a neural tube defect. For spina bifida and cranium bifidum alone, this was also true. For anencephaly, deprivation was less important although the effect of lead was still seen. In some neural tube defects, lead may act independently of other possible factors associated with deprivation. It seemed unlikely that lead levels changed significantly during the survey. The percentage of houses with 10 micrograms/l or more of lead in the water in 1984-5 was similar to that found in Great Britain 10 years previously. CONCLUSION: There is evidence to suggest that lead is one cause of neural tube defects, especially anencephaly. This could link the known preventive actions of hard water and folic acid. Calcium is a toxicological antagonist of lead. One cause of a deficiency of folic acid is impaired absorption secondary to zinc deficiency, which may be produced or exacerbated by lead.     

New non-cocaine-containing topical anesthetics compared with tetracaine-adrenaline-cocaine during repair of lacerations

OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.     

Pregnancy-induced changes in the fibrinolytic balance: evidence for defective release of tissue plasminogen activator and increased levels of the fast-acting tissue plasminogen activator inhibitor

Pregnancy is accompanied by an increased risk of thromboembolic disease. One contributing factor to such disease in the nonpregnant patient is disordered fibrinolysis. It has been suggested that defective fibrinolysis may occur in pregnancy, but this defect has been poorly characterized. In the present study of 52 women with normal pregnancies and 56 nonpregnant control women, we found a marked change in levels of releasable tissue plasminogen activator in pregnant women beginning in the first trimester. Whereas nonpregnant women demonstrated releasable levels of tissue plasminogen activator of 0.74 +/- 0.15 IU/ml of plasma, in the pregnant women the amount released was only 0.06 +/- 0.02 IU/ml of plasma (p less than 0.01). These levels were observed beginning in the first trimester. Levels of the recently described fast-acting tissue plasminogen activator inhibitor increased significantly throughout pregnancy. Values ranged from 8.40 +/- 0.27 IU/ml of plasma in the first trimester to 9.92 +/- 0.09 IU/ml of plasma in the third trimester (p less than 0.05) compared with the level of 8.46 +/- 0.19 IU/ml of plasma in nonpregnant subjects. These data suggest that alterations both in releasable tissue plasminogen activator and in the fast-acting tissue plasminogen activator inhibitor contribute to the physiologic hypercoagulable state of pregnancy.