A computer analysis of reflex eyelid motion in normal subjects and in facial neuropathy.

OBJECTIVE: To demonstrate how computerized eyelid motion analysis can quantify the human reflex blink. DESIGN: Seventeen normal subjects and 10 patients with unilateral facial nerve paralysis were analyzed. BACKGROUND: Eyelid closure is currently evaluated by systems primarily designed to assess lower/midfacial movements. The methods are subjective, difficult to reproduce, and measure only volitional closure. Reflex closure is responsible for eye hydration, and its evaluation demands dynamic analysis. METHODS: A 60Hz video camera incorporated into a helmet was used to analyze blinking. Reflective markers on the forehead and eyelids allowed for the dynamic measurement of the reflex blink. Eyelid displacement, velocity and acceleration were calculated. The degree of synchrony between bilateral blinks was also determined. RESULTS: This study demonstrates that video motion analysis can describe normal and altered eyelid motions in a quantifiable manner. CONCLUSIONS: To our knowledge, this is the first study to measure dynamic reflex blinks. Eyelid closure may now be evaluated in kinematic terms. This technique could increase understanding of eyelid motion and permit more accurate evaluation of eyelid function. Dynamic eyelid evaluation has immediate applications in the treatment of facial palsy affecting the reflex blink. Relevance No method has been developed that objectively quantifies dynamic eyelid closure. Methods currently in use evaluate only volitional eyelid closure, and are based on direct and indirect observer assessments. These methods are subjective and are incapable of analyzing dynamic eyelid movements, which are critical to maintenance of corneal hydration and comfort. A system that quantifies eyelid kinematics can provide a functional analysis of blink disorders and an objective evaluation of their treatment(s).

Angiographic and clinical outcomes following acute infarct angioplasty on saphenous vein grafts.

Acute infarct angioplasty on aortocoronary saphenous vein grafts (SVGs) poses significant challenges because of their degenerate morphology and presence of significant thrombus. Of 370 acute, primary, or rescue myocardial infarct angioplasties performed over 3 years, 21 (5.7%) were on SVGs in patients who had undergone previous coronary artery bypass grafting a mean of 7.2 years earlier. Mean duration of chest pain to start of intervention was 3.9 +/- 3.2 hours; 6 (29%) patients presented with cardiac shock and 4 had failed treatment with thrombolytic drugs. At intervention, 11 (52%) of the culprit SVGs were totally occluded. Flow was reestablished or improved in 18 (86%), but classified as Thrombolysis In Myocardial Infarction trial grade 3 in only 10 patients (48%). Distal embolization and "no reflow" occurred with a frequency of 57% and 71%, respectively. In-hospital mortality was 19%. At 6 months, freedom from death, repeat target vessel revascularization, or recurrent myocardial infarction was 55%. In 349 patients undergoing native vessel intervention, success and Thrombolysis In Myocardial Infarction trial 3 flow rates were seen in 95% and 73% of patients, respectively, and in-hospital mortality was 7.9%. This present study demonstrates that infarct angioplasty on culprit SVGs can be successful but is associated with higher rates of embolic complications and worse acute and long-term clinical outcomes compared with a parallel experience of acute infarct angioplasty on native coronary arteries.

Effects of administration of the chemoprotective agent oltipraz on CYP1A and CYP2B in rat liver and rat hepatocytes in culture.

The success of oltipraz (OPZ) [5-(2-pyrazinyl)-4-methyl-1,2-dithiole-3-thione] as a chemoprotective agent against aflatoxin B1 (AFB1)-induced hepatocarcinogenesis in the rat is thought to depend principally on its ability to enhance detoxication by inducing phase II enzymes, especially glutathione transferases. However, in primary cultures of human hepatocytes, we recently demonstrated that OPZ also has an important inhibitory effect on the major cytochromes P450 (CYPs) of human hepatic AFB1 metabolism. This has prompted a detailed study of the effect of OPZ on some CYPs involved in metabolism of AFB1 in the rat. Primary cultures of rat hepatocytes behaved similarly to human hepatocytes and responded to OPZ by inhibition of ethoxyresorufin-O-deethylase (EROD) and pentoxyresorufin-O-depentylase (PROD) activities mainly associated, respectively, with CYP1A and CYP2B. A time-course shows that this inhibition is largely reversible, with EROD and PROD activities reaching a minimum at 12 h and tending towards control values within 24 h. As is to be expected, the incubation of isolated microsomes with OPZ also inhibits CYP1A and 2B. The effect of OPZ on CYP1A is not a phenomenon limited to cells in culture, but also occurs in vivo. Using the whole animal, we were able to demonstrate that OPZ also transiently inhibited CYP1A activity in a rat given caffeine, by measuring the amounts of methylxanthines found in the serum. However, microsomes isolated from rats, that had been treated with OPZ in vivo, show no such inhibition, presumably because, since OPZ is a reversible inhibitor, it dissociates and is lost during the course of conventional procedures of microsomal preparation. This explains some earlier failures in studies of isolated microsomes to observe the inhibition of CYPs by OPZ. In addition to inhibiting their enzymatic activity, OPZ is also an inducer of CYP1A and 2B as shown by the increased levels of their mRNAs and of caffeine metabolism in vivo after 24 h or more. It is concluded that the mechanism of chemoprotection by OPZ, of toxic chemical metabolism in the rat, is complex and involves competitive inhibition of activation succeeded by induction of the enzymes of both activation and detoxication.

Extraction of fully deployed coronary stents.

Coronary stents are often used because of their potential to improve the acute and long-term results of balloon angioplasty. The Palmaz-Schatz stent has been approved for use by the U.S. Food and Drug Administration largely because of a demonstrated reduction in the incidence of restenosis following its primary implantation. The Gianturco-Roubin design has been approved for use when balloon angioplasty results in threatened or acute vessel closure. In practice, both stent types are being used in settings when the results of balloon angioplasty are either potentially or actually unacceptable. In such circumstances it is imperative that stents be placed accurately and carefully. Occasionally, stent misplacement, embolization, or disruption can occur, and the need arises to recover and/or reposition the wayward prosthesis. This review describes the removal and recovery of fully deployed Gianturco-Roubin stents using an intracoronary snare technique.

Hapten resistant dextran induced ARDS reaction following intracoronary stent deployment.

A case of dextran induced adult respiratory distress syndrome is used to illustrate the most serious complication of dextran usage during intracoronary stent placement. This reaction occurred despite premedication with the hapten dextran 1. Mechanisms of dextran induced complications are discussed. A mechanism for hapten resistant dextran reactions is postulated. Suggestions to prevent such reactions are made.

Experimental comparison of laser and cryosurgical cilia destruction.

We compared cryosurgery with the argon and carbon dioxide lasers in a rabbit model to evaluate the permanence of eyelash destruction as well as the gross and histologic effects on the eyelid. Each modality was equally effective in preventing eyelash regrowth. Cryosurgery and the carbon dioxide laser produced the greatest acute soft tissue swelling; the carbon dioxide laser produced the most pronounced gross eyelid alterations. The argon laser produced minimal eyelid tissue change. Long-term histologic tissue alterations were not striking and were confined to eyelids treated with cryosurgery and the carbon dioxide laser. We conclude that, of the two lasers, the argon is the best suited to the clinical treatment of trichiasis: it is widely available, more precise in limiting contiguous tissue destruction when delivered through a slit lamp, and is safer for use near the eye.

Long-term follow-up of PTCA of the right coronary artery with shepherd's crook morphology.

The authors evaluated the long-term outcome of percutaneous transluminal coronary angioplasty (PTCA) of the right coronary artery in patients with shepherd's crook morphology (51 patients) compared to a control group (53 patients) matched for lesion location, date of procedure, age, and gender. The primary success rate was lower (86% v 98%; P = .03) in the shepherd's crook group than in the control group. At a mean follow-up of 29 months, there was one death in each group. The restenosis rate was 18% in the shepherd's crook group and 21% in the control group; repeat PTCA (14% v 15%) and bypass surgery (2% v 6%) rates were also similar in both groups. The data suggest that PTCA of right coronary arteries with shepherd's crook morphology has a significantly lower primary success rate but similar long-term outcome when compared to PTCA of right coronary arteries without this anatomic variation.

Percutaneous transluminal angioplasty for shepherd's crook right coronary artery stenosis.

Angiograms from 1,043 consecutive patients undergoing right coronary artery angioplasty were reviewed to determine the incidence of "shepherd's crook" origin of the right coronary artery. Primary results, complications, and technical difficulties were compared with a control group. Fifty-one patients (4.9%) were found to have this anatomic variation. Compared with a control group, the primary success rate was lower (86% vs. 98%) and the incidence of procedural difficulties was higher (33% vs. 13%). Technical problems led to the use of more guiding catheters and more guidewires per patient than in the control group. Thus, coronary angioplasty of shepherd's crook right coronary artery imposes technical problems and is associated with less than an optimal primary success rate.

Ultrasonic stimulation of low lumbar nerve roots as a diagnostic procedure: a preliminary report.

Ultrasonation of irritated lumbosacral nerve roots produces radiation of pain into the ipsilateral buttock. If pain is reported when using the ultrasonic stimulator with no sonation, good evidence is obtained that the patient's symptoms are not arising from radicular pathology.