Accuracy of Tongue Swab Testing Using Xpert MTB-RIF Ultra for Tuberculosis Diagnosis.

Tongue dorsum swabs have shown promise as alternatives to sputum for detecting Mycobacterium tuberculosis (MTB) in patients with pulmonary tuberculosis (TB). Some of the most encouraging results have come from studies that used manual quantitative PCR (qPCR) to analyze swabs. Studies using the automated Cepheid Xpert MTB/RIF Ultra qPCR test (Xpert Ultra) have exhibited less sensitivity with tongue swabs, possibly because Xpert Ultra is optimized for testing sputum, not tongue swab samples. Using two new sample preprocessing methods that demonstrated good sensitivity in preliminary experiments, we assessed diagnostic accuracy and semi-quantitative signals of Xpert Ultra performed on tongue swabs collected from 183 adults with presumed TB in Kampala, Uganda. Relative to a sputum Xpert Ultra reference standard, the sensitivity of tongue swab Xpert Ultra was 77.8% (95% confidence interval [CI] 64.4-88.0) and specificity was 100.0% (95% CI, 97.2-100.0). When compared to a microbiological reference standard (MRS) incorporating both sputum Xpert Ultra and sputum mycobacterial culture, sensitivity was 72.4% (95% CI, 59.1-83.3) and specificity remained the same. Semi-quantitative Xpert Ultra results were generally lower with tongue swabs than with sputum, and cycle threshold values were higher. None of the eight sputum Xpert Ultra "trace" or "very low" results were detected using tongue swabs. Tongue swabs should be considered when sputum cannot be collected for Xpert Ultra testing, or in certain mass-screening settings. Further optimization of tongue swab analysis is needed to achieve parity with sputum-based molecular testing for TB.

Calibration of the Gamma Knife using a new phantom following the AAPM TG51 and TG21 protocols.

PURPOSE: To compare calibration of the Leksell Gamma Knife according to the American Association of Physicists in Medicine Task Groups 21 and 51 protocols. A new phantom was fabricated for this purpose. Its design, physical properties, and composition are described. MATERIALS AND METHODS: The Gamma Knife TG-51 calibration phantom is designed to be filled with water and support an ionization chamber positioned at its center. The phantom is thimble-shaped, with a 2 mm plastic wall to contain water. The phantom and chamber assembly was mounted in a Leksell stereotactic frame. The location of the chamber's sensitive volume was determined using computed tomography. The chamber-phantom assembly was attached to the 18 mm helmet in the Gamma Knife by the stereotactic frame. The phantom's geometry allowed radiation beams from each of the 201 Gamma Knife cobalt-60 sources to converge after an 8 cm path to the ionization chamber's sensitive volume. This is similar to the arrangement by which one calibrates the Gamma Knife using the manufacturer-supplied polystyrene phantom. RESULTS: The phantom was attached to the Gamma Knife so that the ionization chamber was reproducibly positioned at the convergence of the radiation beams. Because of the phantom's design, the phantom could be affixed to either trunnions or the automatic patient positioning system, once mounted in the Leksell stereotectic frame. Comparisons using different phantoms and protocols resulted in the following calibration ratios for TG-21 in the polystyrene sphere phantom, TG-21 in the water phantom, and TG-51 in the water phantom, respectively: 1.000, 1.008, 0.986, when corrected for transmission through the plastic water reservoir wall and using the same ionization chamber. Transmission measurements using a 1 cm thickness of the same material in the Co-60 beam determined that the phantom's 2 mm plastic wall resulted in a reduction in the measured the output by 0.5%. CONCLUSIONS: Calibration of the Gamma Knife can be performed in liquid water using the AAPM TG-51 protocol and this new phantom, thereby eliminating uncertainties with respect to the composition of the manufacturer's phantom. Perturbation of calibration measurements by nonwater materials was characterized and could be corrected. Calibration values for the Gamma Knife that were obtained using the three methods for our phantoms agree to within 1.4%. TG21 and TG51 calibration of the Gamma Knife using the water phantom agreed to within 2.2%.

Prolonged P300 latency in a neuropsychiatric population with the D2 dopamine receptor A1 allele.

The role of the dopaminergic system in P300 has been implicated and previous studies have suggested the presence of a heritable component in the genesis of P300 or P3, a late positive component of the event-related potential. In the present investigation, 155 Caucasian male and female diagnosed neuropsychiatrically-ill patients with and without comorbid drug and alcohol abuse/dependence were genotyped for the presence or absence of the A1 allele of the D2 dopamine receptor gene (DRD2). The relationship of the A1 and A2 alleles to P3 amplitude and latency was also determined. The results showed no significant difference in P3 amplitude between all groups studied with A1 and A2 allele carriers. However, we now report prolonged P3 latency in neuropsychiatrically-ill patients (with or without polysubstance abuse) with those carrying two copies of the A1 allele (homozygote) of the DRD2 gene (quadratic trend, p = 0.01). Moreover, the age-adjusted mean P3 latency in the D2A2/A2 allele group was 327.8 +/- 3.08 ms compared by ANOVA, to 360.04 +/- 4.86 ms in the D2A1/A1 group. Our work suggests an association of polymorphisms of the DRD2 gene and a biological marker previously indicated to have predictive value in vulnerability to substance abuse.

Increased prevalence of the Taq I A1 allele of the dopamine receptor gene (DRD2) in obesity with comorbid substance use disorder: a preliminary report.

In order to investigate the prevalence of the Taq I A1 allele of the dopamine receptor gene (DRD2) in obesity with and without comorbid substance use disorder, a total of 40 patients, from an outpatient neuropsychiatric clinic in Princeton, New Jersey, were genotyped for presence or absence of the Taq I DRD2 A1 allele. The primary inclusion criterion for 40 obese subjects was a body mass index (BMI) equal to or over 25 (uncharacterized); 11 obese subjects had severe substance use disorder; 20 controls had a BMI below 25; and, 33 substance use disorder (less severe) patients had a BMI below 25. The data were statistically compared with three different sets of controls divided into three separate groups (Group I, n = 20; Group II, n = 286; Group III, n = 714). They differed according to screening criteria (drug, alcohol, nicotine abuse/dependence, BMI below 25 and other related behaviours including parental history of alcoholism or drug abuse and DSM IV, Axis I and Axis II diagnoses). Groups II and III were population controls derived from the literature. The prevalence of the Taq I A1D2 dopamine receptor (DRD2) alleles was determined in 40 Caucasian obese females and males. In this sample with a mean BMI of 32.35 +/- 1.02, the A1 allele of the DRD2 gene was present in 52.5% of these obese subjects. Furthermore, we found that in the 23 obese subjects possessing comorbid substance use disorder, the prevalence of the DRD2 A1 allele significantly increased compared to the 17 obese subjects without comorbid substance use disorder. The DRD2 A1 allele was present in 73.9% of the obese subjects with comorbid substance use disorder compared to 23.5% in obese subjects without comorbid substance use disorder. Moreover, when we assessed severity of substance usage (alcoholism, cocaine dependence, etc.) increasing severity of drug use increased the prevalence of the Taq I DRD2 A1 allele; where 66.67% (8/12) of less severe probands possessed the A1 allele compared to 82% (9/11) of the most severe cases. Linear trend analyses showed that increasing use of drugs was positively and significantly associated with A1 allelic classification (p < 0.00001). These preliminary data suggest that the presence of the DRD2 A1 allele confirms increased risk not only for obesity, but also for other related addictive behaviours (previously referred to as the Reward Deficiency Syndrome) and that a BMI over 25 by itself (without characterization of macroselection or comorbid substance use disorders) is not a sufficient criterion for association with the DRD2 A1 allele.

Dopamine D2 receptor gene variants: association and linkage studies in impulsive-addictive-compulsive behaviour.

Drug and alcohol seeking behaviour has become a great global problem affecting millions of inhabitants with a cost to society in the billions. Dopaminergic reward pathways have frequently been implicated in the etiology of addictive behaviour. While other neurotransmitters have also been implicated, to date the only molecular genetic defect which has been found to associate with alcoholism, drug dependency, obesity, smoking, pathological gambling, attention-deficit-hyperactivity disorder (ADHD), Tourette syndrome, as well as other related compulsive behaviours, are the variants of the dopamine D2 receptor gene (DRD2). In this review of the available data on the subject, we report a number of independent meta-analyses that confirm an association of DRD2 polymorphisms and impulsive-additive-compulsive behaviour (IACB), which we have termed "Reward Deficiency Syndrome". While we agree that Meta-analyses of all exant studies support an association of variants of DRD2 and IACB, correct negative findings with alcoholism may be due to differences in assessing controls and inclusion/exclusion criteria for selection of diseased probands.

Involvement of folic acid in the synthesis of membrane-associated nucleotide sugars by normal and transformed mouse fibroblasts.

A plasma-membrane-containing fraction isolated from Swiss mouse (3T3) fibroblasts was found to contain uridine diphosphate sugars and methyl-uridine diphosphate (mUDP) sugars. The synthesis of the mUDP sugars by membrane preparations of normal and transformed 3T3 cells occurred from the intrinsic membrane uridine-diphosphate sugars + methylenetetrahydrofolic acid. Compared to the normal 3T3 cells, the synthesis of mUDP sugars by the transformed 3T3 cells was reduced by 49%. It is proposed that the plasma-membrane-associated mUDP sugars may be essential for normal cell growth.

Involvement of methionine in the synthesis of certain membrane-associated nucleotide sugars by human amnion (WISH) cells.

A plasma membrane preparation from human amnion (WISH) cells contained uridine diphosphate sugars and methyl-uridine diphosphate (mUDP) sugars. The synthesis of mUDP-glucose, mUDP-mannose, and mUDP-fucose by the membrane preparation occurred when supplemented with uridine-5'-diphosphate-glucose and S-adenosyl-L-methionine. It is suggested that this newly recognized route for fucose biosynthesis might be employed by certain transformed cells, and may partly account for the methionine dependence of certain human tumors. Additionally, it is suggested that, in colon cancer, a deficiency of folic acid and methionine might affect mUDP-sugar biosynthesis rather than the methylation of DNA.

The role of nonionic myelography in the diagnosis of lumbar disc herniation.

RATIONALE AND OBJECTIVES: The accuracy and safety of nonionic myelography, unenhanced computed tomography (CT), and magnetic resonance (MR) in the diagnosis of lumbar disc herniation are reviewed. The comparative costs of these tests are also considered. METHODS: The accuracy of imaging tests that diagnose disc herniations was established by conducting a Medline search between 1985 and 1992. The morbidity associated with these tests are less formally established from selected articles. Finally, the mediocre reimbursement rates of these tests are reviewed. RESULTS AND CONCLUSIONS: The evolution of nonionic contrast media from the first to the second generation has been accompanied by a notable decrease in adverse reactions. Although nonionic myelograms are now better tolerated by patients, noninvasive imaging with CT and MR imaging has become as accurate as or more accurate than lumbar myelography, and should replace it as a screening test. Computed tomography may have advantages over MR imaging when issues of availability and cost are considered. In contrast to lumbar myelography, CT myelography may continue to be a useful method for clarifying ambiguous results of noninvasive tests. The morbidity associated with CT myelography can be minimized by using low doses of a nonionic agent, keeping the patient well hydrated, and using a small lumbar puncture needle. The incidence of adverse reactions can be expected to decrease further as new nonionic dimers become clinically available.

Assessment of a model for measuring drug diffusion through implant-generated fibrous capsule membranes.

Fibrous tissue, which encapsulates subcutaneously implanted silastic, vinyl, polyurethane and Teflon discs in rats, has been isolated, characterized and tested for drug permeability in order to develop an in vitro model for determining the effect of this tissue on drug disposition from implant sites. With all materials, capsule tissue thickness and collagen content (approximately 59%) was consistent from 2 to 4 months after implantation. Silastic implants afforded the most consistent and usable tissue in terms of thickness and lack of vascularity, and these capsule membranes were used for determining the transport of three model compounds in an in vitro diffusion cell model. The rank ordering of permeability through these membranes was estrone (60.2 x 10(-6) cm s-1) > 3-O-methylglucose (18.7 x 10(-6) cm s-1) > dextran of molecular weight 70 000 (5.6 x 10(-6) cm s-1), which is consistent with expectations based on the molecular weights and partitioning behaviour of the model compounds. The results of these studies indicate that implant-generated encapsulating membranes can be successfully isolated and employed to study drug diffusion in an in vitro model, providing a direct assessment of the barrier properties of encapsulating membranes.

Prevalence, incidence, and risk factors associated with hip fractures in community-dwelling older Mexican Americans: results of the Hispanic EPESE study. Establish Population for the Epidemiologic Study for the Elderly.

OBJECTIVES: To determine the rates and risk factors associated with hip fractures in the community-dwelling older Mexican-American population. DESIGN: A prospective survey of a regional probability sample of older Mexican Americans aged 65 and over. SETTING: The 1993-1996 Hispanic Established Population for the Epidemiologic Study of the Elderly (H-EPESE), a probability sample of noninstitutionalized Mexican Americans, aged 65 and over, living in the Southwestern states of Texas, New Mexico, Colorado, Arizona, and California. PARTICIPANTS: In 1993-1994 and in 1995-1996, 2895 persons, aged 65 and over, considered Mexican American, were selected at baseline as a weighted probability sample. Sample weights were used to extrapolate to the estimated 498,176 older Mexican Americans residing in the Southwest US. MEASUREMENTS: Self-reported hip fracture and functional measures by in home interviews. RESULTS: Hip fracture prevalence was 4.0% at baseline. The overall incidence of hip fractures for women was 9.1 fractures/1000 person-years. The incidence rate for men was 4.8 fractures/1000 person-years. Extrapolation from these data to the entire older Mexican American population indicated that approximately 5162 new fractures occurred in the population during the 2 year study period. In women, hip fractures were associated independently with advanced age, not being married/living alone, having had a stroke, limitations with activities of daily living and instrumental activities of daily living. In men, only the latter limitations were associated independently with hip fracture. CONCLUSIONS: This study indicates that older Mexican American people may have hip fracture incidence rates that place them at highest risk among the Hispanic subgroups. In light of a sparse literature on this population, the fracture estimates derived from this work contributes to our understanding of the true fracture estimates in this population. Based on the extrapolated population rates, hip fracture in this population is a significant public health problem. Adequate preventive measures need to be implemented in this growing US population.

Correlates of prescription and over-the-counter medication usage among older Mexican Americans: the Hispanic EPESE study. Established Population for the Epidemiologic Study of the Elderly.

OBJECTIVES: To determine the prevalence rates of prescription and over-the-counter (OTC) medication usage among community-dwelling older Mexican Americans. DESIGN: Cross-sectional survey of a regional probability sample of older Mexican Americans. SETTING: The 1992-1997 Hispanic Established Population for the Epidemiologic Study of the Elderly (H-EPESE), a probability sample of noninstitutionalized Mexican Americans, age 65 and over, living in the five Southwestern states of Texas, New Mexico, Colorado, Arizona, and California. PARTICIPANTS: 2899 persons, age 65 and over, considered Mexican American, using appropriate weighting procedures to produce regional estimates. OUTCOME MEASURES: Use of prescription and OTC medication within the last 2 weeks before the survey confirmed by in-home review of medication containers. RESULTS: Medication users consumed a mean of 2.9 prescription and 1.3 OTC medications. Over half (58.9%, n = 1,798) of the participants used at least one prescribed medication, and 31.3% (n = 847) used at least one OTC medication within the 2 weeks before their participation in the study. Factors associated with both prescription and OTC medication usage were self-perceived health and number of co-morbid conditions. Factors associated only with prescription medication usage included female gender, alcohol usage, ADL dependency, and presence of additional insurance. Structural assimilation was associated only with OTC medication usage. CONCLUSIONS: These data show lower prevalence rates of prescription medication usage among Mexican American older men and lower rates of OTC medication usage in older Mexican Americans of both genders than previously reported in other ethnic groups. This may reflect differences in time and geographic location of the Hispanic EPESE relative to other EPESE studies, ethnic differences in access to care as reflected by insurance in addition to Medicare, ethnic differences in survival, especially among males, or ethnic differences in medication preferences.

Bilateral anterior transposition of the inferior obliques.

Sixty-one children with bilateral overaction of the inferior oblique muscle with concurrent or previous infantile esotropia received bilateral inferior oblique recessions with anteriorization to a point 2 to 4 mm anterior to the lateral end of the inferior rectus insertion. Subsequent reoperation for recurrent overaction of the inferior obliques was needed in only one case. Also, substantial reduction in dissociated vertical deviation (DVD), when present, and almost complete absence of subsequent need for surgery for DVD among the 61 children of this series were new findings. Only one of the 61 required subsequent surgery for manifest DVD. In another series of 60 infantile esotropes of similar ages drawn from the same practice who had previously had no inferior oblique surgery, nine needed surgery for DVD. This difference (one of 61 vs nine of 60) was significant.

Variability of strabismus surgery for acquired esotropia.

We developed a mathematical model to predict the probable success rate of the first surgery to correct acquired esotropia with normal accommodative convergence-accommodation ratio in children. A computer-averaged dose-response curve of the effect of 68 bilateral medial rectus recessions was combined with various assumptions regarding likely errors in surgical performance and likely errors in measurement of the preoperative deviation. Fifteen different sets of reasonable assumptions were tested, giving a range of theoretical success rates from 72% to 96%. The results of this study clearly indicate that a certain proportion of failures is to be expected when this or other forms of strabismus are treated surgically by a fully competent ophthalmic surgeon performing as accurately as is practically possible.

Birth weight percentile and perinatal outcome: recurrence of intrauterine growth retardation.

In 9596 patients followed throughout two pregnancies, recurrence of intrauterine growth retardation (IUGR) was evaluated as a function of previous birth weight percentile and attendant complications of pregnancy. Among 4623 patients with two uncomplicated pregnancies, the prevalence of recurrent IUGR was significantly related to the severity of growth retardation in the first pregnancy (P less than .0001). Those patients with both medical complications and IUGR in the first pregnancy remained at significantly increased risk for recurrent IUGR, even when the second pregnancy was uncomplicated. In second pregnancies, the combination of a previous history of an IUGR neonate and an additional current complication of pregnancy acted synergistically to increase the risk of recurrent IUGR to a level higher than that attributable to either risk factor alone.

Analysis of birth weight percentile as a predictor of perinatal outcome.

Birth weight-gestational age tables are convenient methods for the neonatal evaluation of intrauterine growth, however, the limits of acceptable birth weight for gestational age are controversial. The purpose of this study was to identify the birth weight percentiles that accurately predicted poor perinatal outcome from 28 through 41 weeks' gestational age. In a homogeneous population of 44,811 patients, the birth weight percentile that predicted poor perinatal outcome varied with gestational age. The birth weight percentile that predicted normal outcome in 80% of normal patients declined from the 55th percentile at 28 to 29 weeks to the 24th percentile at 34 to 35 weeks. From 28 through 35 weeks' gestational age, possibly owing to the confounding effects of prematurity, patients classified as normal by birth weight criteria still had a significant risk of poor outcome. After 36 weeks' gestational age, poor perinatal outcome occurred in 3.9% of patients and tended to occur at the extremes of birth weight. Classification by birth weights approximating the tenth and 90th percentiles identified a population in which the majority of the poor perinatal outcome occurred. However, poor outcome occurred in only 10% of patients with birth weights below the tenth or above the 90th percentiles. Among those with birth weights between the tenth and 90th percentiles, outcome was normal in 98%. Therefore, from 36 through 41 weeks' gestational age, the prevalence of poor perinatal outcome was low, and birth weight percentile was a weak predictor of outcome in the individual patient.

Allelic association of the D2 dopamine receptor gene with cocaine dependence.

The objective of the present study was to examine allelic prevalence of the D2 dopamine receptor (DRD2) gene in male cocaine-dependent (CD) Caucasian (non-Hispanic) subjects and to determine the relationship of DRD2 alleles to family history and selected behavioral measures. The prevalence of the A1 allele in CD subjects (n = 53) was 50.9%. It was significantly higher than either the 16.0% prevalence (P < 10(-4)) in non-substance abusing controls (n = 100) or the 30.9% prevalence (P < 10(-2)) in population controls (n = 265) wherein substance abusers were not excluded. Similarly, a significantly higher prevalence (P < 10(-2)) of the B1 allele was found in CD subjects (n = 52) compared with non-substance abusing controls (n = 53); 38.5% vs. 13.2%. Logistic regression analysis of CD subjects identified potent routes of cocaine use and the interaction of early deviant behaviors and parental alcoholism as significant risk factors associated with the A1 allele. The cumulative number of these three risk factors in CD subjects was positively and significantly (P < 10(-3)) related to A1 allelic prevalence. The data showing a strong association of the minor alleles (A1 and B1) of the DRD2 with cocaine dependence suggest that a gene, located on the q22-q23 region of chromosome 11, confers susceptibility to this drug disorder.

Mechanism of irrigation effects on gingivitis.

Although gingivitis is initiated by plaque and plaque removal controls gingivitis, gingival irrigation with water has been shown to reduce gingivitis without reducing plaque. This study attempted to explore possible mechanisms involved in the treatment of gingivitis by water irrigation. Patients (n = 125) with more than 20 teeth, less than 4 sites with probing depth (PD) deeper than 6 mm, bleeding on probing (BOP) frequency of 30% or higher, and no systemic disease were randomized to one of four treatment groups: toothbrushing alone (brush), toothbrushing plus chlorhexidine 0.12% rinse 2x/day (CHX), toothbrushing plus water irrigation 1x/day (irr+H2O), or toothbrushing plus chlorhexidine 0.04% irrigation 1x/day (irr+CHX). Six sites/tooth were examined at baseline, and at 3 and 6 months for BOP and PD using an automated probe, and for gingival index (GI) and plaque index (PI) by standard means. A prophylaxis and oral hygiene instructions were provided after baseline and 6 month measurements. Subgingival microbial samples and crevicular fluid (GCF) were collected from 2 teeth/subject at each time point. Microbial samples were processed for anaerobic culture and the predominant cultivable flora was determined. CHX and irr+CHX had a 30 to 35% decrease in mean PI, while brush and irr+H2O had only a 12 to 16% decrease. BOP was reduced by 14% in the brush group and 23 to 24% in the other groups. GI was significantly correlated with PI in the brush, CHX, and irr+CHX groups, but not in the irr+H2O group. Prevotella intermedia was significantly reduced in both irrigation groups, but not CHX or brush groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The maximum motor fusion test: a parameter for surgery for acquired esotropia.

PURPOSE: The purpose of this study was to determine whether surgery for acquired esotropia based on the maximum capacity for motor fusion measured with a prism bar could be used to increase the number of millimeters of bilateral medial rectus recession that could be performed without producing an early overcorrection or a late consecutive exotropia, as a way safely to reduce the need for postoperative wear of glasses or a bifocal. METHODS: Category I patients had residual deviations of esotropia (ET) of 12 PD or more with distance fixation, measured after a full hyperopic correction of +1.50 to +3.25 was placed, and had no significant anisometropia or astigmatism. Category II patients had residual deviations of esotropia of less than 11 PD with distance fixation and had residual deviations of esotropia with near fixation (ET') of at least 10 PD more than esotropia with distance fixation ("clinical high AC/A"). Category III patients had had previous bilateral medial rectus muscle recessions and had recurrent esotropia with near fixation of more than 10 PD. For patients in categories I and II, bilateral medial rectus muscle recessions were performed by using a published dose-response table from the national Prism Adaptation Study but with the maximum capacity for motor fusion as the input parameter instead of the prism-adapted angle. Patients in category III received re-recessions of one or both medial rectus muscles, according to a previously published system, with the distance fusional amplitude as the input parameter. RESULTS: In category I, 24 of 30 (80%) patients needed no glasses after surgery, 1 of 30 had esotropia, and 2 of 30 had exotropia (XT) (10% reoperation rate). In category II, 35 of 36 (98%) patients needed no bifocals after surgery, and 3 of 36 had exotropia (9% reoperation rate). In category III, 10 of 10 patients needed no bifocals, and 2 of 10 had exotropia (20% reoperation rate). CONCLUSIONS: When a postoperative reduction in dependence on continuous wear of an optical appliance is a reasonable goal, the maximum motor fusional capacity, measured with a prism bar, is a good parameter for surgical design.

Antielevation syndrome after bilateral anterior transposition of the inferior oblique muscles: incidence and prevention.

BACKGROUND: Unilateral and bilateral anterior transpositions of the inferior oblique muscle (ATIOs) for primary inferior oblique (IO) muscle overaction may produce apparent new or recurrent overaction of the contralateral IO muscle. This effect has been termed "antielevating" and can produce overaction of the contralateral elevators in adduction that mimics recurrent or new overaction of the IO muscle of the other eye. This phenomenon may be termed the antielevation syndrome (AES). Kushner has hypothesized that this complication of the ATIO is produced primarily by the posterior fibers of the IO muscle. The purpose of this study is to correlate the frequency of this syndrome in a large series of patients with the mm of lateral displacement (spreading) of the IO muscle reattachment site. METHODS: There was a combination of 123 patients who received ATIO from Mims and 77 patients who received ATIO from Kushner. ATIO was performed according to a previously published technique. RESULTS: All 16 patients (14 from Mims and 2 from Kushner) with AES had received bilateral anterior transposition of the posterior fibers of the IO muscle to at least 2 mm anterior to the lateral end of the inferior rectus (IR) muscle with spreading laterally 3 to 5 mm. Among children who had the posterior fibers of their IO muscles placed 2 to 4 mm anterior to a line drawn laterally from the insertion of the IR muscle, the incidence of AES was significantly larger with more spreading out of the new IO muscle insertion. CONCLUSIONS: AES may be prevented by attaching the posterior fibers of the IO muscle no more than 2 mm lateral to the IR muscle insertion site. This complication responds to bilateral nasal IO muscle myectomy in many cases.

The D2 dopamine receptor gene as a predictor of compulsive disease: Bayes' theorem.

The dopaminergic system, and in particular the dopamine D2 receptor, has been profoundly implicated in reward mechanisms in the meso-limbic circuitry of the brain. Dysfunction of the D2 dopamine receptors leads to aberrant substance (alcohol, drug, tobacco and food) seeking behavior. Decades of research indicate that genetics play an important role in vulnerability to severe substance seeking behavior. We propose that variants of the D2 dopamine receptor gene are important common genetic determinants in predicting compulsive disease.