Apparent diffusion coefficient in thoracolumbar intervertebral discs of healthy young volunteers.

Apparent diffusion coefficient values (ADC) of healthy intervertebral discs of young volunteers in the thoracolumbar spine were determined using a single-shot EPI sequence. ADC(z) was in the lumbar spine slightly higher than ADC(x) or ADC(y). In vivo diffusion measurements of intervertebral discs may offer a novel diagnostic tool to evaluate disc diseases in early phases.

Comparison of early deflation rate of detachable latex and silicone balloons and observations on persistent varicocele.

PURPOSE: To determine the frequency of and time until spontaneous deflation of detachable embolization balloons made of different materials and the correlation between persisting or recurrent varicocele and the spontaneous deflation of the balloons. MATERIALS AND METHODS: Forty-five patients with clinically detected left-sided varicocele underwent embolization with 78 silicone and 22 latex balloons. The minimum follow-up time was 3 months and the follow-up consisted of clinical examination, color duplex ultrasonography, and plain radiography of the balloons. Those patients who were suspected of having recurrent varicoceles underwent control venography to assess the internal spermatic vein. RESULTS: All of the latex balloons and 10% of the silicone balloons deflated spontaneously during the follow-up. The average time until deflation was 5.1 months for latex and 9.9 months for silicone balloons. Persistence of varicocele, attributed to perfusion through a previously occluded portion of the internal spermatic vein, occurred in two of 11 (18%) recurrences. Nine of 11 (72%) recurrences were due to bypassing collaterals past the site of detachable balloon placement. CONCLUSIONS: Latex balloons seem to predispose more to persisting/recurrent varicocele than silicone balloons. Early deflation of the balloons explained two (18%) of the 11 persisting or recurrent varicoceles. A combination of a sclerosing agent with balloon embolization of the internal spermatic vein is recommended.

Duplex US of the external carotid artery.

The ratio between the systolic peak velocities of the internal and common carotid arteries (vpICA/vpCCA), vpICA and grey-scale imaging measurement are generally used to evaluate internal carotid stenosis against known flow criteria in order to differentiate non-significant from significant stenosis. The same criteria are also used for evaluating the external carotid artery (ECA). Our data on 707 normal or stenotic ECA nevertheless showed that the systolic peak velocity of the normal ECA (vpECA) and its ratio to the systolic velocity of the CCA (vpECA/vpCCA) are higher than vpICA and vpICA/vpCCA. vpECA/vpCCA is about 2 in > 0-49% ECA stenosis. Only in severe stenosis are the peak velocities almost comparable. The ratio between the peak end diastolic velocities (edvECA/edvCCA) and edvECA proved to be unreliable, as did grey-scale imaging measurement of the external carotid stenosis. In addition, ipsi-lateral internal carotid stenosis greatly affects the non-stenotic external carotid flow values, and probably has the same effect on the flow values of a stenotic external artery. Thus, external carotid flow values must be considered carefully.

Nonparasitic splenic cysts. Ultrasonographic features and follow-up.

Sixty-three patients with splenic cysts, multiple in 7 cases, were reviewed. Only 3 patients had a history of previous abdominal trauma. The cysts ranged in size from less than 1 cm to 15 cm. They were anechoic in 40 patients, hypoechoic in 16, isoechoic in 4, mixed in one, and in 2 cases the echogenicity could not be assessed due to thick marginal calcifications. The echogenic cysts were larger than the anechoic ones and frequently calcified, and the findings at surgery, fine-needle aspiration biopsy and follow-up suggested the echogenicity to be related to a fresh or previous episode of intracystic hemorrhage. Initially, surgical treatment was undertaken on 10 patients, electively in 9 cases and due to cyst rupture in one. At follow-up (n = 37), the size of the cyst had increased markedly over several years in only 2 patients, necessitating delayed surgery in one. Routine follow-up of asymptomatic splenic cysts was of no clinical value.

Abdominal ultrasonography in myelofibrosis.

The findings at abdominal ultrasonography (US) in 40 patients with myelofibrosis were reviewed, 20 patients being examined at initial diagnosis and 31 at later stages. Splenomegaly was found in 80% at initial diagnosis and in 97% at later stages. The spleen of 2 patients appeared homogeneously hypoechoic and inhomogeneous in one. Focal splenic lesions were seen in 5, and calcifications in 6. Mixed splenic lesions proved to be metastases in one and hyperechoic lesions in another patient were due to extramedullary hematopoiesis. Hepatomegaly was found in 25% at primary diagnosis and in 39% at later stages. Focal hepatic lesions were seen in 7 patients, and proved to be metastases in 3. The focal lesions in 2 of these patients were extramedullary hematopoiesis, which was hypoechoic in one and hyperechoic in the other. Ascites was seen in 4 patients and lymphadenopathy in one. US could not reliably differentiate between extramedullary hematopoiesis and malignancy. Fine-needle biopsy may be performed for definitive diagnosis.

Magnetic resonance of diseased skeletal muscle: combined T1 measurement and chemical shift imaging.

Magnetic resonance examinations of skeletal muscle with differential T1 relaxation time measurements were performed in 19 patients with muscular dystrophies and congenital myopathies, and in eight control subjects. A field echo chemical shift imaging technique was used. T1 values of muscular tissue were measured from the primary composite images, and differential T1 values were calculated separately from water and fat images. Longitudinal relaxation times of skeletal muscle were significantly increased in both dystrophies and myopathies. The results of differential relaxation time measurements suggest that intramuscular fat reduces the abnormal increase in T1 of diseased muscle tissue. When characterizing diseases of skeletal muscle by T1 relaxation time measurements, the contribution of secondary fatty infiltration must be considered.

The assessment of colonic water retention prior to double-contrast enema.

The detection of colonic water retention prior to double-contrast enema (DCE) was studied in 41 outpatients. Ultrasound examination of the cecum (USC) correctly showed 4 of the 5 patients with water retention as well as all 14 cases with dry colon. Changes in patient's weight or in the number of cleansing enemas were not associated with water retention. The USC seems to offer a rapid and accurate method for the detection of colonic water retention prior to DCE. Aspects of the handling of colonic water retention are also discussed.