Body weight and blood pressure. Effects of weight reduction on hypertension

A substudy of the Hypertension Optimal Treatment study, conducted in the Jackson Mississippi Center, set out to determine the link between obesity and hypertension and to determine the effects of weight loss in hypertensive individuals. An analysis of the relationship between body mass index and diastolic blood pressure for another study showed that increasing body mass indices were associated with increases in blood pressure. This indicates that not only is there a strong relationship between obesity and hypertension, but that there is also a close association between the continuous variables of body mass index and blood pressure. The purpose of the present study was to determine the effectiveness of a weight loss regimen in reducing the amount of medication required to achieve the target blood pressure in 228 patients at the Jackson center. Subjects were randomized to a dietary intervention group or to a control group. Preliminary 3 month observational data showed that subjects who lost the appropriate amount of weight were three times more likely to achieve their target blood pressure at 3 months. These observations suggest that weight reduction regimens can reduce elevated blood pressure and can probably promote further blood pressure reductions when combined with drug therapy in the treatment of hypertension.

Computerized Wisconsin Card Sorting Test: comparison with manual administration

Computer-based testing in neuropsychology potentially offers important advantages. These include improvement in reliability and more efficient use of resources. For tests such as the Wisconsin Card Sorting Test (WCST) in which examiners must provide on-going feedback to subjects, reliability may be decreased by variability and errors in test presentation, errors in response recording and feedback, and errors in scoring. In addition, an important aspects of neuropsychological assessment is qualitative, that is, observations of the processes by which the subject responds to the test situation. The mechanics of administering the WCST hinder the examiner from allocating attention for observing these processes. Accordingly, we have automated both the administration and the scoring of the WCST. Although potential benefits of computerizing the WCST seem likely, it is possible that factors which cannot at present be duplicated by a computer may effect performance. This study compared performance between the standard manual Heaton version of the WCST and the computerized version. In a group of 33 normal and psychiatric subjects, there were significant differences in the number of Errors and the number of Correct responses, but no significant differences in performance were found for Perseverative Responses, Perseverative Errors, and Set Breaks. The mean number of Categories achieved was 2.0 for the computer administered version and 2.4 for the manual version: this difference was only marginally significant (p = 0.065). The computerized form of the WCST appears to yield similar quantitative results on scores which are most specifically affected by brain injuries in testing with the manual form. Lower variance was seen in the computer scores. This result is consistent with more reliable administration and accuracy in data acquisition and scoring in the computer version. The results overall indicate that the computer version is not a substitute for a human examiner, rather, the computer can function as a reliable partner, carrying out the mechanics of test presentation and scoring, freeing the examiner to more fully support the subject in taking the test and to observe the non-quantitative aspects of test performance.

Effect of ranitidine on theophylline metabolism in healthy Koreans living in China

OBJECTIVE

To evaluate the effect of concurrent ranitidine therapy on theophylline metabolism in healthy Koreans.

DESIGN

A 4-week, double-blind, randomized, placebo-controlled, crossover study.

SETTING

The Clinical Research Unit, Department of Pharmaceutical Sciences, Yanbian Medical College, Yanji, China.

SUBJECTS

Six young, healthy, nonsmoking Korean volunteers residing in China with no known factors that would alter theophylline metabolism.

INTERVENTIONS

Subjects received extended-release oral theophylline at a constant dosage over 4 weeks to yield a serum concentration (Cp) between 5 and 10 micrograms/mL. Week 1 was the dosage titration phase. During week 2 subjects randomly received either ranitidine or a matching placebo. Week 3 was a washout phase, and during week 4 subjects were crossed over to receive either placebo or ranitidine. At the end of each treatment week, serum and urinary metabolite concentrations were measured.

OUTCOME MEASURES

Theophylline serum concentrations and urinary concentrations of 1-methylxanthine, 1-methyluric acid, 3-methylxanthine, and 1,3-dimethyluric acid were measured. Estimates of clearance (Cl), volume of distribution (Vd), and half-life (t1/2) were determined.

RESULTS

Concurrent administration of ranitidine with theophylline did not significantly alter theophylline Cp, Cl, Vd, or t1/2. Urinary concentrations of major theophylline metabolites also were not changed.

CONCLUSIONS

Ranitidine does not significantly alter the metabolism of theophylline in healthy Koreans residing in China.

Cardiovascular effects of cocaine in neonates exposed prenatally

This blinded cross-sectional study was to determine whether chronic cocaine exposure in utero produces abnormalities in left ventricular function (shortening fraction), heart rate, rhythm, and conduction in term neonates. Three groups of neonates were evaluated by two-dimensional echo Doppler and 24 hour Holter monitor, with studies initiated in the first 24 hours of life. Group A (n = 32) neonates had a positive history of chronic maternal cocaine use in pregnancy (MCU+) and a positive neonatal urine cocaine test (NUC+). Group B (n = 23) neonates were MCU+ but NUC-. Group C (n = 32) neonates were MCU- and NUC-. Measured parameters were compared statistically by analysis of variance. p < 0.05 was regarded as significant. Echocardiography showed no significant difference between groups A, B, and C for left ventricular shortening fraction. Holter monitor likewise revealed no significant difference between groups in minimal, maximal, and average heart rate, or in the incidence of supraventricular and ventricular arrhythmias greater than 20 beats/h in the 24-hour period. None of the patients had atrioventricular or bundle branch block. It is possible that the developmental state of the newborn heart makes it less responsive to the adverse effects of cocaine.

Superior temporal gyrus volume in schizophrenia: a study using MRI morphometry assisted by surface rendering

OBJECTIVE

Interpretation of the literature concerning superior temporal gyrus volume in patients with schizophrenia is complicated by methodological variation between studies and by the difficulty of identifying gyral boundaries in serial sections.

METHOD

With the aid of three-dimensional cortical renderings, the authors developed a morphometric approach in which information from the cortical surface is incorporated into gyral boundary decisions. Using this technique, they assessed superior temporal gyrus volume in young, right-handed male patients with schizophrenia and in right-handed male comparison subjects. They also compared their technique with existing slice-based morphometric methods by using previously reported subcortical landmarks to define the gyral boundaries.

RESULTS

There was no significant main effect of diagnosis and no significant diagnosis-by-hemisphere interaction. Significant leftward laterality was present only among comparison subjects. Leftward superior temporal gyrus laterality did not correlate with leftward laterality of the planum temporale. No significant reduction in superior temporal gyrus volume was revealed in the patients. No significant leftward laterality was detected with the slice-based technique, suggesting that a significant portion of superior temporal gyrus tissue is omitted with this approach. The lack of findings could not be explained by a general absence of morphometric abnormalities in this group of subjects because the patients had significantly larger lateral ventricles.

CONCLUSIONS

Significant reduction in the superior temporal gyrus volume was not confirmed in this group of patients with schizophrenia, probably because of the small effect size of this finding. Methodological variation is an important factor in determining superior temporal gyrus volume on magnetic resonance imaging scans.

Characterization of experimental composite biomaterials

A comparison was made among the elastic moduli of various combinations of dimethacrylates that may be used as matrix resins in dental restorative composite biomaterials systems. Two ceramic filler materials with contrasting shape and size were synthesized by wet chemistry; these were used to produce a range of experimental composite systems. Dynamic elastic moduli determinations were used to study the influence of filler volume, filler size/shape, use of silane coupling agents, and storage in water. The filler was varied from 0 to 59% by volume for filler A and from 0 to 48% volume for filler B. Silane treatment was found to have a significant effect on modulus. Moduli for composite materials containing silane-treated filler were higher compared to materials containing the same volume loading of non-silane-treated filler. Using a light curing resin as a matrix gave a significantly higher modulus for a filler loading of 38% by volume. Storage in water for 29 days was found to have only a slight effect on moduli for composite systems containing in excess of 20% by volume of filler. The experimental composite systems produced slightly higher values for moduli than were predicted by the theoretical Reuse constant stress model.

Hypertension in East Asia

Asians comprise the largest single ethnic group in the world and the fastest growing minority ethnic group within the United States. The prevalence of hypertension in most Asian groups is similar to that of non-Asians. The associations with hypertension are similar to those seen in Western populations. Body mass index is a surprisingly strong predictor of blood pressure, even in very lean Asian populations. Studies in Asian groups suggest that the prevalence of target organ disease as related to hypertension are dependent on other cardiovascular disease risk factors. Stroke is more common than heart disease in Asia. Hypertension treatment data in East Asia is sparse, and treatment methods vary widely. Hypertension control among the world's largest ethnic group remains a challenge.

Differential cholinergic regulation in Alzheimer's patients compared to controls following chronic blockade with scopolamine: a SPECT study

The effects of low-dose chronic scopolamine on measures of cerebral perfusion and muscarinic receptors were tested in eight Alzheimer's disease (AD) subjects and eight elderly controls. Single photon emission computed tomography (SPECT) scans using technetium-labelled hexamethypropylene amine oxide (99mTc-HMPAO) to measure cerebral perfusion before and after chronic scopolamine revealed a significant 12% increase in the normal controls (P < 0.01) while the AD subjects showed no significant change. In contrast, the controls showed decreased muscarinic binding as evidenced by 123I-quinuclidinyl-4-iodobenzilate (123I-QNB) labelling after chronic drug (-10%, P < 0.01) whereas the AD subjects showed increased 123I-QNB labelling (+8%, P < 0.05). The difference between AD and control subjects was even more marked when the ratio of I-QNB to HMPAO uptake was compared, pointing to a double dissociation in the SPECT results. These data cannot be explained by group differences in cerebral perfusion alone and suggest a differential sensitivity between AD and elderly controls to chronic cholinergic blockade.

Lateralized differences in iodine-123-IBZM uptake in the basal ganglia in asymmetric Parkinson's disease

We used equilibrium analysis of SPECT data from patients with asymmetric Parkinson's disease to determine if lateralized differences in the striatal uptake of [123I]IBZM correlate with asymmetry in clinical findings and, by inference, with lateralized differences in the concentration of extracellular dopamine.

METHODS

Twelve patients with asymmetric clinical signs of idiopathic Parkinson's disease were injected with a bolus of [123I]IBZM, and multiple SPECT scans recorded the time course of radioligand uptake. The time integral method was used to estimate peak specific binding, so that a ratio of specific-to-nonspecific binding in the left and right striatum of each subject at equilibrium could be determined. Nine patients also had 99mTc-HMPAO SPECT scans which were examined for evidence of blood flow asymmetries.

RESULTS

Paired t-tests comparing [123I]IBZM uptake revealed significantly greater (mean = 7.3%) availability of dopamine-D2 receptors in the basal ganglia contralateral to maximal clinical signs. Differences in receptor availability correlated significantly with differences in every measure of the clinical assessment. No significant differences in regional cerebral blood flow between the two sides were observed with 99mTc-HMPAO.

CONCLUSION

These results demonstrate the ability of [123I]IBZM SPECT to reveal clinically meaningful variations in striatal dopamine receptor availability in patients with asymmetric Parkinson's disease. The equilibrium analysis technique used to determine these findings is a simple and robust method of measuring relative receptor availability and may be useful in studying other illnesses where dysfunction of dopaminergic neurotransmission is suspected.

Normal asymmetry of the planum temporale in patients with schizophrenia. Three-dimensional cortical morphometry with MRI

BACKGROUND

Abnormal cerebral anatomical lateralisation has been reported in schizophrenia and may implicate anomalous neurodevelopment in the aetiology of this disease. A popular recent hypothesis has predicted that such disturbances in normal lateralisation should be especially apparent in the morphology of the temporal lobes.

METHOD

A temporal cortical region lying in the plane of the Sylvian fissure--known as the planum temporale--exhibits pronounced leftward asymmetry in normal right-handed males. We compared lateralisation of the planum temporale in schizophrenic and control males using MRI surface-rendering morphometry of the supratemporal cortex.

RESULTS

Contrary to the lateralisation hypothesis, normal patterns of leftward planum asymmetry were detected in both the schizophrenic and control groups. Schizophrenics and controls also exhibited a predicted symmetry in the bilateral areas of Heschl's gyrus, a supratemporal cortical structure immediately anterior to the planum.

CONCLUSION

These data do not support the notion that neurodevelopmental mechanisms of cerebral asymmetry are abnormal in schizophrenia.

Body mass index and blood pressure in Korean men and women: the Korean National Blood Pressure Survey

AIMS AND METHODS

The association between body mass index (BMI) and blood pressure is well known in relatively obese populations. The purpose of the present study was to investigate the relationship between BMI and blood pressure in a lean population. Through cluster sampling, individuals aged > 30 years in 190 out of 154,082 districts were selected for study. Among 25,567 eligible individuals, measurements of blood pressure and BMI were made in 22,354.

RESULTS

The BMI for males was 22.8 +/- 2.7 kg/m2 and for females was 23.4 +/- 3.2 kg/m2 (means +/- SD). Over a BMI range from 16 to 31 kg/m2 the relationships between BMI and systolic and diastolic blood pressure were almost linear. Over the BMI range 25-31 kg/m2 (overweight-to-obese) each BMI unit was associated with a difference of 1.0 mmHg in diastolic blood pressure. Over the BMI range 16-25 kg/m2 (normal-to-lean) each BMI unit was associated with a difference of 0.89 mmHg in diastolic blood pressure.

CONCLUSION

We conclude that a strong association between BMI and blood pressure exists for lean as well as for obese subjects.

Mercury vapour suppression by various liquid media

Fresh and used photographic fixer, Merconvap and water were evaluated for their ability to suppress the vapourization of mercury. Mercury vapour concentration above the four test storage liquids was measured at various times between 10 min and 335 days, using a mercury vapour measuring instrument. The data were analysed using a Student-Newman-Keuls multiple comparison test (P = 0.05). The results showed that fresh and used fixer and Merconvap suppressed the vapourization of mercury to below the detection limit of the measuring instrument (0.01 mg/m3). Water was much less effective compared with the other liquids and showed an increase in mercury vapour concentration with log t.

Lack of effect of hydrocholorthiazide on total cholesterol

To determine the effect of hydrochlorothiazide on total cholesterol, baseline total cholesterol and blood pressure were determined in 618 hypertensive subjects in a hypertension clinic in Pusan, Korea. After 12-24 months (mean follow-up time 14 months), total cholesterol and blood pressure measurements were repeated. In the group whose therapy included hydrochlorothiazide (n = 436), total cholesterol fell by 8 +/- 39 mg/dL. Those not treated with a diuretic (n = 182) had an identical fall in total cholesterol of 8 +/- 42 mg/dL (P < 0.001 for change from baseline). Patients with a baseline total cholesterol > 200 mg/dL were asked to reduce intake of saturated fat. Change in total cholesterol for 180 patients on this diet and hydrochlorothiazide was -24 +/- 31 mg/dL (P < 0.0001); for 71 patients on the diet and non-diuretic therapy, change was -22 +/- 35 mg/dL (P < 0.0001). There was no change in total cholesterol in either drug group for those with a baseline value < or = 200 mg/dL. It is concluded that in this group of Korean patients on a relatively low-fat diet, a low dose of hydrochlorothiazide had no adverse effect on total cholesterol at 14 months, and hydrochlorothiazide nor other agents prevented a beneficial effect of further reduction of saturated fat on total cholesterol.

Hypertension in Korea: a national survey

To determine the prevalence of hypertension (HTN) and its risk factors, we performed a population-based national cross-sectional blood pressure (BP) survey in Korea in 1990. Through cluster sampling, we selected for study individuals older than 30 years of age in 190 of 154,082 districts. Among 25,567 eligible individuals, 21,242 subjects had measurements of BP and body mass index (BMI) and underwent a standard interview. BP was recorded as the mean of two measurements on a standard mercury manometer. The prevalence of HTN varied widely by area of residence. Overall prevalence was 19.8% for HTN defined as BP > or = 140/90 mm Hg or subject on medication, and 12.4% for BP > or = 160/95 mm Hg or subject on medication. Correlates for HTN identified by logistic regression analysis included positive family history of HTN (odds ratio [OR] = 2.2,), age (10 years); OR = 1.9), alcohol intake (500 cc; OR = 1.4), urban location (versus rural; OR = 1.3), and BMI (1 BMI unit; OR = 1.2). [Am J Prev Med 1994;10:200-4]

Bioavailability of digoxin tablets in healthy volunteers

The bioavailability of digoxin generic tablets manufactured in Korea (formulations A & B) were compared to a standard (formulation C; Lanoxin brand digoxin, Burroughs Wellcome, USA) in 12 healthy Korean male volunteers (mean age 31.4 years) in a single dose, randomized, complete block crossover study. Using a Latin square design, each of the subjects was randomized to the order number and allocated to each of the three treatments of 0.5 mg oral digoxin. Digoxin concentrations in serum and urine samples collected for 48 hours after dosing were measured by fluorescence polarization immunoassay and radioimmunoassay, respectively. Treatments were compared by using nonlinear least squares regression analysis to evaluate the following pharmacokinetic parameters: maximum serum concentration (Cmax); time of maximum serum concentration (Tmax); area under the serum concentration-time curve for 0-12 hours (AUC0-12); and cummulative urinary excretion for 0-48 hours (CUE0-48). Mean AUC0-12, Cmax, and CUE0-48 values for formulations B and C were significantly different from formulation A (p < 0.001), but not significantly different from each other. Based on AUC0-12 and CUE0-48, respectively, the relative availability of formulation B was 87.5% and 89.6% and the relative availability of formulation A was 43% and 35% when compared to formulation C (the standard).

Theophylline disposition in Korean patients with congestive heart failure

OBJECTIVE

This study proposed to determine the systemic disposition of theophylline in Korean adult patients during decompensated congestive heart failure compared with disposition after recovery.

DESIGN

An experimental, prospective, self-controlled, nonrandomized design was used.

SETTING

The study was performed in a general community hospital located in Pusan, Korea.

PATIENTS

Eight nonsmoking elderly Korean patients with decompensated congestive heart failure presenting to the emergency department were included in the study. Consecutive patients who met entrance criteria were selected. All patients completed the study.

INTERVENTIONS

A single dose of aminophylline 6 mg/kg was administered by intravenous infusion over 30 minutes. Standard methods of congestive heart failure therapy were used in each patient, including bed rest, restriction of sodium, and drug therapy including digoxin. After compensation of congestive heart failure was achieved, the theophylline infusion was repeated.

OUTCOME MEASURES

Serum theophylline concentrations were measured at 2, 6, 12, and 18 hours after completion of the dose at baseline and following treatment.

RESULTS

A clinically and statistically significant improvement in mean theophylline total body clearance was demonstrated following treatment (from 21.7 +/- 2.8 to 43.4 +/- 4.7 mL/kg/h [mean +/- SEM]; p < 0.01). Comparison of these results with a computer model based on literature averages of peoples of all nationalities showed significant underprediction of theophylline clearance both before (p < 0.05) and after (p < 0.01) treatment. The theophylline elimination half-life prior to treatment was 18.2 +/- 2.2 hours and decreased to 9.1 +/- 0.8 hours following treatment (p < 0.01). There was no statistical difference between the computer-model predicted initial theophylline half-life and the measured value, but the model significantly underpredicted the improvement following treatment.

CONCLUSIONS

The improvement in theophylline clearance demonstrated in this study appears to be greater than that reported for Western patients. This has practical application to the calculation of appropriate theophylline maintenance dosage regimens in Korean patients with cardiac failure. These data support the need for consideration of racial differences in individualizing dosage regimens. We suggest that all kinetic models, whether software supported or not, should consider incorporating ethnic origin as a demographic factor that helps select the proper model for individual patients.

Gender differences in the normal lateralization of the supratemporal cortex: MRI surface-rendering morphometry of Heschl's gyrus and the planum temporale

Gender differences in hemispheric asymmetry for language functioning have been reported in the neuropsychological literature. Despite numerous reports of anatomic asymmetries in corresponding cortical regions, the possibility of gender dimorphism in the putative neuroanatomical substrate of language has not been systematically examined in vivo. We assessed asymmetry of the planum temporale (PT), a supratemporal region of auditory association cortex, in 12 normal, right-handed females and 12 age-matched right-handed males with the aid of MRI surface-rendering morphometry. Bilateral areas were also assessed for Heschl's gyrus (HG), a supratemporal region of primary auditory cortex where no asymmetry was anticipated. We found a significant interaction between gender and hemisphere for the PT, with males having significantly larger left versus right PTs. Left-right differences in PT area were not significant among females (10 of 12 males showed leftward lateralization of the PT, vs 5 of 12 females). No main effect of gender was found for total (left + right) PT area, and no asymmetries or gender effects were detected for HG. This finding of gender dimorphism in PT area is consistent with evidence for reduced asymmetry among females in the lateralization of language functions attributable to the supratemporal cortex. The implications for theories about interactions between sex hormones and the development of brain asymmetries are discussed.

Arthrogenic quadriceps inhibition and rehabilitation of patients with extensive traumatic knee injuries

1. The relationship between joint damage, quadriceps weakness and arthrogenic muscle inhibition was investigated in eight patients who had sustained extensive traumatic knee injury. Isometric and isokinetic quadriceps and hamstring voluntary strength, and quadriceps arthrogenic muscle inhibition during isometric contractions, were measured before and after 4 weeks (approximately 100 h) of intensive rehabilitation. 2. Compared with the uninjured leg, before rehabilitation the injured leg had larger amounts of quadriceps arthrogenic muscle inhibition (P < 0.025), quadriceps (P < 0.0001) and hamstring (P < 0.0001) weakness and severe functional joint instability. There was a negative correlation between the amount of arthrogenic muscle inhibition and quadriceps voluntary contraction force (P < 0.025). 3. After rehabilitation in the injured leg there were small hamstring strength increases (P < 0.05-0.025), but no overall significant quadricep strength increase. Arthrogenic muscle inhibition was statistically unchanged. Severe functional joint instability was still reported by all patients. 4. Previous studies have shown that minimal joint damage evokes relatively less arthrogenic muscle inhibition that does not impede rehabilitation. These data indicate that greater joint damage is associated with greater arthrogenic muscle inhibition, quadriceps weakness and joint instability. Furthermore, intensive rehabilitation had little affect on either quadriceps arthrogenic muscle inhibition or atrophy.

Sylvian fissure asymmetries in monozygotic twins: a test of laterality in schizophrenia

To address prior reports that schizophrenia is associated with loss of normal brain asymmetry and that it might be linked to a defect of a gene controlling cerebral lateralization, we measured on three-dimensional cortical renderings from magnetic resonance imaging (MRI) scans the lengths and angles of the sylvian fissures in 10 normal monozygotic (MZ) twin pairs (n = 10 pairs) and in 10 MZ pairs discordant for schizophrenia (n = 10 pairs). We confirmed in both sets of twins the expected normal asymmetries of length and angle of the sylvian fissure. We also confirmed that the length asymmetry occurs solely in the region of the planum temporale. In the discordant twins, affected and unaffected twins did not differ in asymmetry measures, thus failing to support an association between illness per se and diminished asymmetry. Moreover, the discordant twins as a group did not differ from the normal twins as a group, thus failing to confirm the hypothesis of a genetic association with abnormal asymmetry. The implications of variations in methodology and patient samples are discussed.

Effects of doxazosin and hydrochlorothiazide on lipid levels in Korean patients with essential hypertension

Because none of the major studies used to document adverse or beneficial metabolic effects of antihypertensive drugs were made of non-Western patients with a non-Western diet, we compared doxazosin and hydrochlorothiazide in Korean patients receiving a Korean diet to determine if one regimen is superior to the other in terms of efficacy, adverse metabolic effects, or both. The randomized, double-blind, parallel study of Korean hypertensive patients compared the effects of oral doxazosin (mean +/- SD dose, 10.3 +/- 6.3 mg/day) and oral hydrochlorothiazide (44.0 + 11.0 mg/day) on blood pressure (BP) and lipid metabolism. The results of 48 patients treated for 20 weeks are reported here. Systolic (p < 0.001) and diastolic (p < 0.001) BP (SBP, DBP) were significantly lower in both groups at the end of the treatment period. Doxazosin significantly increased high-density-lipoprotein (HDL) cholesterol from a baseline of 1.10 +/- 0.31 to 1.27 +/- 0.30 mM (p < 0.05) and HDL/total cholesterol from 0.25 +/- 0.1 to 0.28 +/- 0.1 mM (p < 0.01). Hydrochlorothiazide significantly increased triglyceride from a baseline of 1.63 +/- 0.71 to 2.02 +/- 0.87 mM (p < 0.05). In contrast to Western studies, hydrochlorothiazide demonstrated no adverse effect on total, low-density-lipoprotein (LDL), or HDL cholesterol, or on HDL/total cholesterol. Indeed, HDL cholesterol was increased by 0.16 mM (p < 0.01). As in Western patients, doxazosin is effective for treatment of essential hypertension in Koreans and has no adverse effects but some beneficial effects on lipids.(ABSTRACT TRUNCATED AT 250 WORDS)

Three-dimensional surface rendering in MRI morphometry: a study of the planum temporale

OBJECTIVE

The emergence of methodologies for accurately rendering cortical surfaces suggests possible quantitative applications of surface rendering to morphometry of the cerebral cortex. We examined this novel use of surface renderings in a study of the planum temporale, a neuroanatomical structure exhibiting well-documented normal asymmetry previously visible only in postmortem studies.

MATERIALS AND METHODS

With the aid of three-dimensional renderings of the supratemporal cortex, the area of the planum temporal was analyzed in the volume MRIs of seven normal, strongly right-handed males.

RESULTS

In comparison with areas derived from conventional measurements of serial MRI sections, planum temporale areas derived from supratemporal surface renderings offered far greater interrater reliability, and presumably improved validity as reflected by more consistent evidence of the anticipated planum asymmetry.

CONCLUSION

Morphometry of the supratemporal cortex is enhanced by the use of three-dimensional surface renderings. Application of surface-rendering techniques to morphometry of other cortical regions is discussed.