Clinically Feasible Microstructural MRI to Quantify Cervical Spinal Cord Tissue Injury Using DTI, MT, and T2*-Weighted Imaging: Assessment of Normative Data and Reliability

BACKGROUND AND PURPOSE

DTI, magnetization transfer, T2*-weighted imaging, and cross-sectional area can quantify aspects of spinal cord microstructure. However, clinical adoption remains elusive due to complex acquisitions, cumbersome analysis, limited reliability, and wide ranges of normal values. We propose a simple multiparametric protocol with automated analysis and report normative data, analysis of confounding variables, and reliability.

MATERIALS AND METHODS

Forty healthy subjects underwent T2WI, DTI, magnetization transfer, and T2*WI at 3T in <35 minutes using standard hardware and pulse sequences. Cross-sectional area, fractional anisotropy, magnetization transfer ratio, and T2*WI WM/GM signal intensity ratio were calculated. Relationships between MR imaging metrics and age, sex, height, weight, cervical cord length, and rostrocaudal level were analyzed. Test-retest coefficient of variation measured reliability in 24 DTI, 17 magnetization transfer, and 16 T2*WI datasets. DTI with and without cardiac triggering was compared in 10 subjects.

RESULTS

T2*WI WM/GM showed lower intersubject coefficient of variation (3.5%) compared with magnetization transfer ratio (5.8%), fractional anisotropy (6.0%), and cross-sectional area (12.2%). Linear correction of cross-sectional area with cervical cord length, fractional anisotropy with age, and magnetization transfer ratio with age and height led to decreased coefficients of variation (4.8%, 5.4%, and 10.2%, respectively). Acceptable reliability was achieved for all metrics/levels (test-retest coefficient of variation < 5%), with T2*WI WM/GM comparing favorably with fractional anisotropy and magnetization transfer ratio. DTI with and without cardiac triggering showed no significant differences for fractional anisotropy and test-retest coefficient of variation.

CONCLUSIONS

Reliable multiparametric assessment of spinal cord microstructure is possible by using clinically suitable methods. These results establish normalization procedures and pave the way for clinical studies, with the potential for improving diagnostics, objectively monitoring disease progression, and predicting outcomes in spinal pathologies.

Medication Antiparkinsonienne et Bilan Extra-Pyramidal: Etude du Trihexyphenidyl

This study, made on 60 chronic mental patients, had aimed to determine the effective dosage of trihexyphenidyl, an antiparkinsonian drug. During the preliminary period all patients were given a standard medication consisting of a neuroleptic, trifluoperazine 60 mg. daily, and an antiparkinsonian agent, trihexyphenidyl 10 mg. daily. A placebo was substituted for the antiparkinsonian during the first experimental period to measure the patients' extrapyramidal sensitivity. This evaluation was performed with a rating scale (B.E.P.) and observations from the nursing staff.

Patients were divided into three groups of 20 according to their B.E.P. score and received one of the three therapeutic regimens: trihexyphenidyl 15 mg. or 6 mg. or placebo.

Analyses of the results allow us to conclude that for this population a daily dosage of 6 mg. of trihexyphenidyl gives as much protection as 15 mg.; patients receiving an antiparkinsonian agent needed less “p.r.n.” administration of prociclydine. We have also found that if the antiparkinsonian drug can control some extrapyramidal symptoms it might be responsible for the presence of other more complex neurological symptoms.

A Novel MRI Biomarker of Spinal Cord White Matter Injury: T2*-Weighted White Matter to Gray Matter Signal Intensity Ratio

BACKGROUND AND PURPOSE

T2*-weighted imaging provides sharp contrast between spinal cord GM and WM, allowing their segmentation and cross-sectional area measurement. Injured WM demonstrates T2*WI hyperintensity but requires normalization for quantitative use. We introduce T2*WI WM/GM signal-intensity ratio and compare it against cross-sectional area, the DTI metric fractional anisotropy, and magnetization transfer ratio in degenerative cervical myelopathy.

MATERIALS AND METHODS

Fifty-eight patients with degenerative cervical myelopathy and 40 healthy subjects underwent 3T MR imaging, covering C1-C7. Metrics were automatically extracted at maximally compressed and uncompressed rostral/caudal levels. Normalized metrics were compared with t tests, area under the curve, and logistic regression. Relationships with clinical measures were analyzed by using Pearson correlation and multiple linear regression.

RESULTS

The maximally compressed level cross-sectional area demonstrated superior differences (P = 1 × 10^-13), diagnostic accuracy (area under the curve = 0.890), and univariate correlation with the modified Japanese Orthopedic Association score (0.66). T2*WI WM/GM showed strong differences (rostral: P = 8 × 10^-7; maximally compressed level: P = 1 × 10^-11; caudal: P = 1 × 10^-4), correlations (modified Japanese Orthopedic Association score; rostral: -0.52; maximally compressed level: -0.59; caudal: -0.36), and diagnostic accuracy (rostral: 0.775; maximally compressed level: 0.860; caudal: 0.721), outperforming fractional anisotropy and magnetization transfer ratio in most comparisons and cross-sectional area at rostral/caudal levels. Rostral T2*WI WM/GM showed the strongest correlations with focal motor (-0.45) and sensory (-0.49) deficits and was the strongest independent predictor of the modified Japanese Orthopedic Association score (P = .01) and diagnosis (P = .02) in multivariate models (R² = 0.59, P = 8 × 10^-13; area under the curve = 0.954, respectively).

CONCLUSIONS

T2*WI WM/GM shows promise as a novel biomarker of WM injury. It detects damage in compressed and uncompressed regions and contributes substantially to multivariate models for diagnosis and correlation with impairment. Our multiparametric approach overcomes limitations of individual measures, having the potential to improve diagnostics, monitor progression, and predict outcomes.

Bioavailability, pharmacokinetics, and clinical effects of an oral preparation of etoposide

Bioavailability of an oral preparation of the antineoplastic drug etoposide (VP-16) was studied in 13 patients with advanced malignancies. An initial pilot study involving three patients suggested that approximately 50% of an orally administered dose was absorbed. Ten additional patients were randomized to receive either 100 mg/m2/day iv or 200 mg/m2/day orally. Three weeks later, the alternate dose schedule was administered. Plasma samples were assayed for VP-16 using a high-pressure liquid chromatography technique. Comparison of the area under concentration-time curves (C X t) revealed that 17%-72% (mean, 52%) of an orally administered dose was absorbed. Absorption was less than 40% for only one patient. For oral and iv preparations, mean peak plasma VP-16 concentrations were 9.6 and 13.0 micrograms/ml, mean alpha-half-lives were 0.96 and 0.82 hour, mean beta-half-lives were 7.2 and 6.8 hours, mean C X t values were 75.9 and 75.3 mg/L/hour, mean plasma clearances were 1.44 and 1.45 L/hour/m2, and mean extrapolated volumes of distribution were 15.2 and 16.9 L/m2, respectively. The half-life for oral absorption was 0.44 hour and peak plasma concentrations were noted 0.5-3 hours after oral drug administration. Granulocyte count nadirs tended to be lower in patients with high C X t values and low plasma clearance values. Granulocytopenia was dose-limiting. Gastrointestinal toxicity was extremely mild. We recommend doses of oral VP-16 of 800 mg/m2/course over 3-5 days for patients with a moderate amount of prior treatment. It is probable that previously untreated patients will tolerate a higher dose and that heavily pretreated patients will require a lower dose.

Radiographic evaluation of the symptom-producing adenoid

Adenoid hypertrophy has several variable symptoms. In this study, symptoms were divided into minor and major. A lateral radiograph of the nasopharynx was performed in 114 patients to study the superior and antroadenoid diameters. With proper statistical analysis, a correlation was made between the various clinical groups (scores) and the adenoid measurements. Our results support Hibbert's findings that the antroadenoid width is a better indicator of the symptom-producing adenoid than adenoid mass measurements with their loosely defined norms. A thorough history and physical examination remain paramount in the diagnosis and management of adenoid hypertrophy.

Bromocriptine therapy in oligozoospermic infertile men

A prospective, randomized double-blind study with crossover using bromocriptine and placebo was performed on a group of 17 infertile males with idiopathic oligozoospermia. Twelve patients completed the duration of this study of eight months by receiving 5 mg of bromocriptine per day for four months followed by four months of placebo or vice versa. Prior to treatment, the sperm count was 8.76 +/- 1.32 (10(6)/ml). The hormonal profile was performed prior to treatment and included estimation of prolactin, T3, T4, thyroid stimulating hormone (TSH), testosterone, follicle stimulating hormone (FSH), and plasma LH. Stimulation studies using LHRH and TRH were also performed. All hormonal estimations were within normal limits. Compared to placebo, bromocriptine had no significant effect on sperm analysis, or basic hormonal profile. The stimulation test with luteinizing hormone releasing hormone (LHRH) was unchanged except for the basic plasma testosterone, which increased. The prolactin decreased following the thyrotropin releasing hormone (TRH) stimulation. Two pregnancies were noted four to six weeks following the end of treatment. Bromocriptine did not seem to be more effective than placebo in the treatment of idiopathic oligozoospermia.

Facial nerve sutures: epineural vs. perineural sutures

The orbicularis oculi branch of the facial nerve was transected in two groups of 15 cats. Following section of the nerve, a specimen was removed for histological studies; then, using microscopic techniques the epineurium was sutured (nylon 10:0) in the first group, and the perineurium in the second. They were then followed for 100 days. Results rely on clinical (complete closure of the eye), electrophysiological (summation potentials), and histological (fiber count) evaluations. Judging from the relative density and diameters of the fibers, epineural sutures result in better regeneration than perineural sutures. With the tremendous importance of the absence of tension on the suture line in mind, it seems that the technique of choice for monofascicular nerves, as in the pyramidal and tympanic segments of the facial nerve, is epineural suture. Despite the slight advantage of epineural suture over perineural suture as evidenced by histological evaluation, there was no clinical difference. The distal fascicular distribution of facial nerve fibers and their spatial distribution make perineural (fascicular) sutures the method of choice when anastomosis becomes necessary in the vertical portion and in the portion distal to the stylomastoid foramen.

Serous otitis media: a six week prospective study

The purpose of this project was to attempt to outline the natural history of serous otitis media. Sixty-eight children with uni or bilateral serous otitis media were placed under observation for a six week period. They were all left untreated. Otoscopy, impedance, and audiogram measurements were used to monitor the evolution of the disease. Results showed that spontaneous resolution occurred in 35 per cent of cases. Girls were cured more frequently than boys. Furthermore, the disease receded more satisfactorily in the right than in the left ear. Within our group of patients, age was not a factor in the evolution of the otitis. Finally, the impedancometry and audiometry were not useful in assessing the probable evolution of this disease.

[Effect of a high serum uric acid diet and injections of urate crystals on adjuvant arthritis in the rat]

The difference between gout and rheumatoid arthritis was reproduced experimentally in the rat by combining adjuvant arthritis with an oxonate uric acid raising diet and injections of crystals of sodium urate. The factorial experiment using 3 factors confirms the inhibition or arthritis by a uric acid raising diet and shows that the injections of crystals, which preceed the injection of Freund's adjuvant, increase the arthritic lesions in normo-uricemic rats and reduces them slightly in hyperuricemic rats. This effect of the injection of crystals increases gradually with time.

Comparative therapeutic factors in schizophrenia

A comparative psychiatric study which evaluated the effects of milieu, group psychotherapy and occupational therapy on sixty-four chronic schizophrenic female patients has been described. These patients had been hospitalized for a mean period of seventeen years, eight months. Two of the factors, milieu and occupational therapy, did not significantly affect the patients' psychiatric condition as assessed by the three rating scales. The third factor, group psychotherapy, did significantly (p < 0.05) reduce the degree of anxiety without modifying the mental state or the behaviour.

A fourth factor, repetition of the experiment, has been statistically analysed indicating that some elements deriving from the milieu may have been responsible for the higher degree of anxiety in the first group of patients.

Psychosomatic medicine. Side effects of oral contraceptive medication: a psychosomatic problem

It has been shown that physcial and psychological manifestations appearing very early after the commencement of oral contraceptive medication can hardly be attributed to oestrogen effects, but are more likely to be due to fear and the anticipation of ill effects. Of the multitude of physical and psychological manifestations complained of by women on the drug some are of somatic origin and others of psychological origin, and women who are emotionally well-adjusted are less likely to report side effects than those who are emotionally maladjusted. Some reasons for depressive spells and for decline in libidinal interest on oral contraceptive medication have been discussed. One factor which emerged is that some women who ask for safe contraceptives, in fact hanker for pregnancy and childbirth, while contraception signifies prevention of impregnation for the time being — temporary infertility. Infertility however temporary and however planned and the unwarranted dread of permanent infertility have a profound emotionally disturbing effect on many women.

The results obtained should be considered with due regard for possible methodological errors. For instance it might be objected that no control group was used, but to find a control group for studies of this kind is difficult and to use women on a placebo as controls is obviously out of the question. The general validity of the observation may be limited because the women in this study were either Jewish or Anglo-Protestants. Differences might have been seen had members of other ethnic or religious groups been studied. The retrospective nature of the investigation might imply some distortions, but the use of semi-structured interviews with specific items on a ranging scale partially obviated the possible impressionistic quality of the material. The ‘halo effect’ which occurs in a personal interview was corrected by the introduction of multi-raters and the experienced clinical judgment of the investigators.

At the outset the intention was to find out which side effects of anovulants are biological in origin and which are psychological. This objective has been accomplished to some extent, but more important perhaps are the practical implications of the research. On the strength of these observations a gynæcologist or a family physician may be well-advised to listen with the ‘third ear' to a woman who consults him, in order to make sure that she really wants a safe contraceptive and not a baby. Undue anxiety regarding the ill effects of the pill, fostered by alarming reports spread by the mass media, should be dispelled. Before prescribing the pill, evidence of emotional maladjustment in the woman or problems in her marriage (sexual or other) should be looked for. The physician should also look for reasons for depression and for decline in libidinal interest in the woman when placed on contraceptive medication. In others words, he should concern himself with the personality of his patient, rather than confining himself to her biological functions.

[Survey on humanitarian and authoritarian attitudes in employees of a large psychiatric hospital]

The staff of a large psychiatric hospital were investigated concerning their attitude toward mental patients. This was done by means of a stochastic transversal survey. A random sample (15%), stratified according to professional activity, was reached by one interviewer using a French translation and adaptation of the “Composite Mental Illness and Social Attitudes Scales.” With analyses of variance and analyses of correlation significant factors influencing attitudes were identified: age, education, type of work, marital and social status. For the whole population the humanitarian index was found predominant over the custodial index.

Phenothiazine treatment and electrocardiographic abnormalities

We have received the literature on ECG. abnormalities found in patients treated with phenothiazines. A survey of 106 electrocardiograms of patients receiving thioridazine as the only neuroleptic has been made. Fifty-nine patients (55.6%) had ECG. abnormalities considered ‘specific' to thioridazine. No statistically significant correlation could be made on the one hand with the sex of the patient, his age, duration of treatment, dosage level, use of antiparkinsonian medication and on the other hand the presence or absence of ECG. abnormalities. It is suggested that the ECG. abnormalities represent a disturbance in many patients with a particular susceptibility to the drug which is unpredictable at present.

[Comparative study of fluphenazine ethanate, fluphenazine bichlorhydrate and placebos in chronic schizophrenics]

A comparative study of fluphénazine enanthate, a long-acting neuroleptic, fluphénazine bichlorhydrate and placebo was made on 28 chronic schizophrenics. The double-blind technique was possible by giving to the patients one of the three following treatments: the long-acting neuroleptic by injection every fortnight and placebo tablets daily, the standard neuroleptic (tablets) daily and regular injection of sesame oil or the two inactive substances in a similar way. Dosage of fluphénazine enanthate was 25, 50 or 75 mg every fortnight and of bichlorhydrate 10, 20 or 30 mg. daily after a fixed schedule.

Antipsychotic action of the drugs was evaluated according to three types of measures: 1) IMPS; 2) NOSIE and 3) need for chlorpromazine given p.r.n. (indirect measure).

Results of this study indicate that both fluphénazine salts are superior to placebo and possess significant antipsychotic properties as demonstrated by the indirect measure. No significant difference was found between enanthate and bichlorhydrate of fluphénazine.

Some methodological aspects of psychopharmacological research are also discussed.

[Neuroleptics and extrapyramidal effects: correlation between antipsychotic and extrapyramidal properties]

Data obtained in two comparative controlled studies of neuroleptics were used to ascertain if there were some correlation between the degree of improvement in the mental state and the severity of extrapyramidal symptoms induced in patients receiving one or other of the following neuroleptics: trifluperidol, trifluoperazine, T.P.S.-23 and chlorpromazine. In this study patients are used as experimental units. For each trial, the importance of psychiatric symptoms has been measured with the Brief Psychiatric Rating Scale and the neurological syndrome with the “Bilan extra-pyramidal” (Extrapyramidal Rating Scale).

It has been impossible to find a correlation between the antipsychotic and extrapyramidal-inducing properties of the neuroleptics we have studied.

[Utilization of thiothixene in the treatment of mania: Pilot study]

Nine manic patients have been the subjects of a pilot study with a new thioxanthene derivative, thiothixene. Data obtained from two rating scales indicate a significant improvement of the mental and behavioural conditions after three weeks of treatment. Thiothixene like other well-known neuroleptics induces extra-pyramidal symptoms and this tends to confirm the fact that thiothixene is a neuroleptic. The drug was well tolerated; however, we observed a decrease of prothrombin time in four patients.

[Sleep-inductive properties of nitrazepam]

A double-blind comparative study made between nitrazepam 10 and 20 mg. secobarbital 200 mg. and placebo has pointed out the sleep-inductive properties of this 1–4 benzodiazepine derivative. Answers to a questionnaire were controlled by direct observations of the sleep-induction period.

Subjective and objective data prove that nitrazepam 10 and 20 mg. and secobarbital 200 mg. shorten sleep induction. A very high negative correlation was found between the two types of data.

The hypnotic action of nitrazepam was again formed as for quality and duration of sleep. Easiness of awakening and alertness of the subject during the forenoon as well as side effects were also analyzed. The effective and well-tolerated dosage of nitrazepam is 10 mg; awakening and alertness of the subject are affected by a higher dosage.