Axial loaded MRI of the lumbar spine.

Magnetic resonance imaging is established as the technique of choice for assessment of degenerative disorders of the lumbar spine. However, it is routinely performed with the patient supine and the hips and knees flexed. The absence of axial loading and lumbar extension results in a maximization of spinal canal dimensions, which may in some cases, result in failure to demonstrate nerve root compression. Attempts have been made to image the lumbar spine in a more physiological state, either by imaging with flexion-extension, in the erect position or by using axial loading. This article reviews the literature relating to the above techniques.

Chronic groin pain in an athlete: an unusual presentation.

Persistent disabling groin pain in an active sportsman is a frustrating diagnostic and management problem for both the athlete and physician. After clinical examination and investigation there remains a group of patients who have unexplained groin pain, and may undergo lengthy periods of conservative management with numerous radiological investigations. Here we highlight such a case.

Sonography, CT, CT sialography, MRI and MRI sialography in investigation of the facial nerve and the differentiation between deep and superficial parotid lesions.

Our aim was to explore the possibility of delineation of the facial nerve within the parotid gland and to differentiate between superficial and deep parotid lesions in relationship to it, using ultrasound, CT, MRI, MRI sialography (MRIS) and CT sialography (CTS). We examined 47 patients with clinically suspected parotid tumours by US, 31 of them also by CT, MRI and CTS, and 13 by MRIS as well. Low-intensity curvilinear structures seen on T1-weighted MRI were delineated better after intraductal gadolinium injection and proved to represent parotid ducts on CTS. Using the main parotid duct as a landmark, we distinguished parotid lesions as deep or superficial to the facial nerve by T1-weighted MRI images in 69% and by MRIS in all cases. The facial nerve itself was indistinguishable from the parotid gland in all our imaging methods.

A synthetic dural prosthesis constructed from hydroxyethylmethacrylate hydrogels.

Hydroxyethylmethacrylate (HEMA) hydrogels were investigated for their suitability as a dural prosthesis. Poly-HEMA has many characteristics required for an artificial dural substitute: it is durable, flexible, easily prepared, inexpensive, easily sterilized and handled, easily shaped, and known to be chemically inert and nontoxic. Sheets made of plain HEMA were evaluated as dural substitutes in rats and rabbits after either craniotomy or laminectomy with durectomy. Histological evaluations of the prostheses and the underlying tissues were undertaken at various time points from 2 to 9 weeks postoperatively. There was minimal tissue response to the implanted HEMA gel in contrast to marked thickening of the overlying leptomeninges and cortical herniation in the control animals. It is concluded that HEMA gels fulfill the essential criteria for an effective dural substitute.

The effects of cocaine exposure prior to and during pregnancy in rats fed low or adequate protein diets.

Sprague-Dawley rats were fed a diet of low protein content (6% casein), an isocaloric diet of adequate protein content (25% casein), or a laboratory chow diet for 5 weeks prior to mating and throughout pregnancy. Within each diet group, rats received either cocaine (30 mg/kg IP two times per week prior to mating and 30 mg/kg or 40 mg/kg SC daily from days 3 to 18 of pregnancy) or saline injections. Cocaine produced a greater reduction in food intake during pregnancy in the malnourished group compared with the other two diet groups. The effect of cocaine on food intake was minimal in chow-fed rats. Weight gain in pregnancy was reduced by cocaine in a dose-dependent manner, and by malnutrition. Both prenatal cocaine and malnutrition impaired skeletal maturation of the pups, but there was no additive effect of the two insults on this measure. Litter size was significantly reduced by the 40 mg/kg, but not by the 30 mg/kg dose of cocaine across all diet groups. Consequently, the 40 mg/kg dose of cocaine proved to be fetotoxic in this model. Birth weight was significantly reduced by prenatal malnutrition but not by prenatal cocaine. Gestation length was unaffected by either insult. Hence, the ability to detect a diet x drug interaction was dependent upon the variable being measured.

Does scrotal ultrasound reduce the need for orchidectomy in the clinically malignant testis?

Many recent studies have confirmed the ability of ultrasound to elucidate scrotal pathology, but its place in the work-up of specific testicular problems is not yet fully defined. We investigated 15 cases where a firm clinical diagnosis of testicular malignancy was made. All cases progressed to orchidectomy. Scrotal ultrasound refuted the diagnosis of malignancy in seven cases with subsequent histological proof of benignity. However, the nature and extent of the benign disease was such that, on review, orchidectomy was considered to be the most appropriate method of treating the patient. We contend that in the case of firm clinical diagnosis of testicular malignancy, an ultrasound diagnosis of benignity will not alter management, and it is therefore not an essential part of the work-up in this group of patients.

What is the clinical significance of urethroprostatic reflux as a radiological finding during videocystourethrography in neurologically normal patients?

The video records of 264 males referred for videocystometry were reviewed retrospectively for evidence of urethroprostatic reflux. This was found in 11% of the cases with three distinct patterns; during bladder filling (27%); during voiding (50%), and during the 'stop test' (23%). All cases with filling reflux were unstable. Reflux at the time of the stop test was usually associated with prostatic or bladder neck obstruction. Voiding reflux occurred in a similar group of patients but there was often a clinical history of the previous surgical relief of obstruction or documented urinary infections. Recognition of this sign suggests the transmission of high pressures to the prostatic urethra and contrary to previous work is uncommonly associated with a history of lower urinary tract pain in cases where it may otherwise go unexplained.

Asymptomatic bladder neck incompetence in nulliparous females.

This study investigated 29 nulliparous women using the technique of transvaginal ultrasound to assess whether their bladder necks were open or closed at rest. The patients comprised 2 groups: 4 reported occasional episodes of stress incontinence, all of whom had closed bladder necks; the remaining 25 patients were totally asymptomatic. Overall a 21% incidence of an open bladder neck was recorded. It is likely that the true incidence of open bladder necks in young nulliparous women is higher than this, since none of these patients had troublesome stress incontinence. Since women with open bladder necks are more likely to develop stress incontinence if the integrity of the distal sphincter mechanism is compromised by neural damage, antenatal recognition of this problem should provide a contraindication to traumatic vaginal delivery and may in the future reduce the incidence of symptomatic stress incontinence in the population.