Breast dynamic contrast-enhanced examinations with fat suppression: are contrast-agent uptake curves affected by magnetic field inhomogeneity?

OBJECTIVES

To investigate the effect of magnetic field heterogeneity in breast dynamic contrast-enhanced examinations with fat saturation (DCE-FS).

METHODS

The magnetic field was mapped over the breasts in ten patients. DCE-FS was undertaken at 1.5 T with fast spoiled gradient echoes and spectrally selective fat saturation. Signal intensity was calculated for T1 values 25-1,200 ms both on and off resonance, and results were verified with a test object. Clinical examinations were evaluated for the predicted effects of field heterogeneity.

RESULTS

Magnetic field was found to vary by 3.6 ± 1.2 ppm over the central transaxial slice and 5.1 ± 1.5 over the whole breast volume (mean ± standard deviation). Computer simulations predict a reduction in the dynamic range if field heterogeneity leads to unintended water suppression, and distortion to CA uptake curves due to fat suppression failure (for fat containing pixels). A compromise between dynamic range and fat saturation performance is required. Both water suppression and fat suppression failure are apparent in clinical examinations.

CONCLUSION

Magnetic field heterogeneity is likely to reduce the sensitivity of DCE-FS by distorting the CA uptake curves because of fat suppression failure (for fat containing pixels) and by reducing the dynamic range because of unintended water suppression.

KEY POINTS

• Magnetic field heterogeneity is significant in breast magnetic resonance. • Contrast-agent uptake curves are distorted by a non-uniform magnetic field. • Radiologist must be aware of possibility of distortion to interpret uptake curves correctly. • Compromise between fat suppression and dynamic range is required.

The fear of prostate cancer in men with lower urinary tract symptoms: should symptomatic men be screened?

OBJECTIVE

To explore the concerns and worries in men with uncomplicated lower urinary tract symptoms (LUTS, but no evidence of prostate cancer) relating to their symptoms.

PATIENTS AND METHODS

There is no current prostate cancer screening programme in the UK. Evidence suggests that men with LUTS have the same risk of prostate cancer as aged-matched asymptomatic men. However, most men with LUTS are 'screened' with a digital rectal examination (DRE) and prostate specific antigen (PSA) testing as part of routine assessment. Whether this screening offers any benefit to patients and whether national screening for prostate cancer and subsequent early treatment offer any long-term survival or quality of life benefit is uncertain. Thus 30 men with uncomplicated LUTS were qualitatively interviewed to explore their concerns and worries about their symptoms. Interviews were transcribed verbatim and subjected to content analysis using validated techniques.

RESULTS

Of the 30 men, 22 (73%) expressed a fear of prostate cancer at the time of their initial presentation. This fear was independent of race, social class and symptom severity; older men were less worried. Of the 22, 15 (68%) stated that after reassurance their symptoms were less bothersome and easier to cope with.

CONCLUSIONS

These findings suggest there is a considerable gain in health by explicitly addressing the concerns of prostate cancer in men with uncomplicated LUTS. Informing these men of their true risk of prostate cancer (before or after a DRE and PSA estimate) may alleviate much of the bother associated with their symptoms. Despite no evidence of any greater risk of prostate cancer than in asymptomatic men, symptomatic men should continue to be screened after appropriate counselling.

Diagnosis of amblyopia using the 10-diopter fixation test: a proposed modification for patients with unilateral ptosis

PURPOSE

The 10-diopter (D) fixation test is a useful test for detecting amblyopia in children without a manifest deviation and in whom a reliable visual acuity assessment is difficult. The 10 prism diopter is conventionally placed base down.

METHODS

Seventeen children were studied over a 12-month period to determine the effect of prism orientation on the accuracy of the 10-D fixation test in children with unilateral ptosis.

RESULTS

Anomalous results were obtained in 4 of 17 patients with the prism held base up and base down.

CONCLUSIONS

To prevent an erroneous diagnosis of amblyopia in children with unilateral ptosis, the prism should be held base up when performing the 10-D fixation test.

A survey of continuing dental education in the South and Mid-West Region of the Postgraduate Medical and Dental Board

This paper presents the data from the analysis of Feedback Questionnaires obtained from dentists who attended Continuing Education Courses run by the Postgraduate Medical and Dental Board, South & Mid-West Region from 1992 to 1994. The implications of the findings are discussed.

A survey of continuing dental education in the South and Mid-West Region of the Postgraduate Medical and Dental Board

This paper presents the data from the analysis of Feedback Questionnaires obtained from dentists who attended Continuing Education Courses run by the Postgraduate Medical and Dental Board, South & Mid-West Region form 1992 to 1994. The implications of the findings are discussed.

Torticollis secondary to ocular pathology

We report a series of 15 children, six male and nine female, of average age 20 months, seen at a paediatric orthopaedic clinic with torticollis. Orthopaedic examination revealed a normal range of neck movement in all cases but in seven there was palpable tightness in the absence of true shortening or contracture of the sternomastoid muscle. The patients were prospectively referred for ocular examination. In five of the 15 an ocular cause for the torticollis was detected with underaction of the superior oblique muscle in three, paresis of the lateral rectus muscle in one and nystagmus in one. Another two patients were found to have an abnormal ocular examination which was thought to be unrelated to their torticollis. Three of the patients with ocular torticollis required extra-ocular muscle surgery to abolish the head tilt and one of these had a tight sternomastoid muscle. Two of the non-ocular group had surgical release of the sternomastoid muscle; in the rest, the condition either resolved with physiotherapy or required no active treatment. We recommend that all patients with torticollis and no clear orthopaedic cause are referred for ocular assessment since it is not possible clinically to distinguish ocular from non-ocular causes.

Superior oblique tendon lengthening for acquired superior oblique overactions

Two patients who presented with compensatory head postures and diplopia are described. They both had marked unilateral superior oblique overaction, in one patient due to a large, incomitant skew deviation. Each underwent a superior oblique tendon lengthening procedure using a segment of silicone 240 retinal band as an expander, in combination with a contralateral superior rectus recession. Both achieved an excellent result with an improvement of the compensatory head posture and an increase in the field of binocular single vision. This surgical procedure is proposed as an option in the management of superior oblique overaction, including certain cases of skew deviation.

Tuberose Sclerosis with Rhabdomyomata in the Heart: Pathological Specimens

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