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Background: Acute community-acquired sinusitis is considered a bacterial complication of the common cold. Radiologic abnormalities in sinuses occur, however, in most patients with upper respiratory virus infections. Objective: Assessment of the occurrence, clinical profile, laboratory findings, and outcome of radiologically confirmed sinusitis was carried out as part of a common cold study in young adults. Methods: Clinical examinations and radiography of the paranasal sinuses were carried out on days 1, 7, and 21 in 197 patients with the common cold. The symptoms were recorded on diary cards on days 1 to 20. Ten viruses and 5 bacteria were studied as etiologic agents of common cold as reported earlier. Serum C reactive protein concentrations, erythrocyte sedimentation rates, and total white blood cell counts with differentials were determined in 40 randomized subjects on day 7. The effect of 6 days of intranasal fluticasone propionate treatment of the common cold in the prevention of sinusitis was analyzed. Results: On day 7, 39% of patients with the common cold in the placebo group ( n = 98) had sinusitis, which we would prefer to call viral sinusitis. The symptoms of patients with sinusitis and those without it were not clinically distinguishable. Viral infection was detected in 81.6% of patients with sinusitis. No significantly increased levels of antibodies to bacteria were detected. Serum C reactive protein concentrations, erythrocyte sedimentation rates, and white blood cell counts were low in patients with sinusitis. All patients made a clinical recovery within 21 days without antibiotic treatment. Fluticasone propionate treatment tended to prevent paranasal sinusitis, especially in rhinovirus-positive subjects. Conclusion: Viral sinusitis frequently occurs in the early days of the common cold, but it is a self-limited illness. The sinuses should not be imaged in patients with the common cold if the signs and symptoms of illness gradually become less severe and no specific signs suggestive of bacterial sinusitis occur. (J Allergy Clin Immunol 1998;102:403-8.)

1. The role of blood flow as a determinant of skeletal muscle glucose uptake is at present controversial and results of previous studies are confounded by possible direct effects of vasoactive agents on glucose uptake. Since increase in muscle blood flow can be due to increased flow velocity or recruitment of new capillaries, or both, it would be ideal to determine whether the vasoactive agent affects flow distribution or only increases the mean flow. 2. In the present study blood flow, flow distribution and glucose uptake were measured simultaneously in both legs of 10 healthy men (aged 29 +/- 1 years, body mass index 24 +/- 1 kg m-2) using positron emission tomography (PET) combined with [15O]H2O and [18F]fluoro-2-deoxy-D-glucose (FDG). The role of blood flow in muscle glucose uptake was studied by increasing blood flow in one leg with sodium nitroprusside (SNP) and measuring glucose uptake simultaneously in both legs during euglycaemic hyperinsulinaemia (insulin infusion 6 pmol kg-1 min-1). 3. SNP infusion increased skeletal muscle blood flow by 86 % (P < 0.01), but skeletal muscle flow distribution and insulin-stimulated glucose uptake (61.4 +/- 7. 5 vs. 67.0 +/- 7.5 micromol kg-1 min-1, control vs. SNP infused leg, not significant), as well as flow distribution between different tissues of the femoral region, remained unchanged. The effect of SNP infusion on blood flow and distribution were unchanged during infusion of physiological levels of insulin (duration, 150 min). 4. Despite a significant increase in mean blood flow induced by an intra-arterial infusion of SNP, glucose uptake and flow distribution remained unchanged in resting muscles of healthy subjects. These findings suggest that SNP, an endothelium-independent vasodilator, increases non-nutritive, but not nutritive flow or capillary recruitment.

In gyrate atrophy of the choroid and retina with hyperornithinaemia (GA), a genetically determined deficiency of ornithine delta-aminotransferase activity leads to high ornithine concentrations in body fluids. GA is characterized by centripetally progressing retinal and choroidal destruction and selective atrophy with tubular aggregates in type II skeletal muscle fibres. These findings have been suggested to be mediated by hyperornithinaemia-induced deficiency of high-energy creatine phosphate. As abnormal brain magnetic resonance images and electroencephalograms are found in another disorder of creatine metabolism, guanidinoacetate methyltransferase deficiency, we investigated the central nervous system involvement in GA, which seems to be associated with a milder degree of phosphocreatine deficiency. We compared 23 untreated GA patients with age-matched healthy controls, and with 9 patients who had received creatine or creatine precursor supplementation daily for several years. The mean age of the patients (32 +/- 18 years) was similar to that of the controls (36 +/- 22 years). The MRI or EEG findings of the patients on creatine supplementation did not differ from those of the untreated group. Brain MRI revealed degenerative lesions in the white matter in 50% of the GA patients, and 70% of the patients had premature atrophic changes, with a striking increase in the number of Virchow's spaces. Of the patients whose EEG was recorded, 58% had abnormal slow background activity, focal lesions or high-amplitude beta rhythm (50 microV). The EEG findings were not associated with the MRI changes or with the age or the sex of the patients. Early degenerative and atrophic brain changes and abnormal EEG are thus features of GA, in addition to the well-characterized eye and muscle manifestations.

Purpose: To determine whether low-field MR fat/water separation and magnetisation transfer (MT) techniques are useful in studying the livers of patients with parenchymal liver diseases in vivo. Material and Methods: MR and MT imaging of the liver in 33 patients (14 with primary biliary cirrhosis, 15 with alcohol-induced liver disease, and 4 with fatty liver) was performed by means of the fat/water separation technique at 0.1 T. The relaxation time T1 and the MT contrast (MTC) parameter of liver and spleen tissue were measured, and the relative proton density fat content N(%) and MTC of the liver were calculated from the separate fat and water images. The value of N(%) was also compared with the percentage of fatty hepatocytes at histology. Results: The relaxation rate R1 of liver measured from the magnitude image, and the difference in the value of MTC measured from the water image compared with the one measured from the fat and water magnitude image, both depended linearly on the value of N(%). The value of N(%) correlated significantly with the percentage of the fatty hepatocytes. In in vivo fatty tissue, fat infiltration increased both the observed relaxation rate R1 and the measured magnetisation ratio (the steady state magnetisation Ms divided by the equilibrium magnetisation Mo, Ms/Mo) and consequently decreased the MT efficiency measured in a magnitude MR image. The amount of liver fibrosis did not correlate with the value of MTC measured after fat separation. Conclusion: Our results in studying fatty livers with MR imaging and the MT method show that the fat/water separation gives more reliable parametric results. Characterisation of liver cirrhosis by means of the MTC parameter is not reliable, even after fat separation.

The purpose of this study was to evaluate 1/T1rho in relation to 1/T1 and 1/T2 in characterizing normal and diseased muscle. We measured the muscle relaxation rates 1/T1 and 1/T2 at 0.1 T and 1/T1rho at on-resonance locking fields B1 between 10 and 160 microT in myositis patients and normal volunteers. 1/T2 and 1/T1rho of muscle were lower in the patients than in the volunteers, whereas there was no difference in the 1/T1 values. The lower relaxation rates 1/T2 and 1/T1rho in the diseased muscle may be due to fat and connective tissue infiltrations and edema. 1/T1rho contrast between muscle and subcutaneous fat was higher than 1/T2 and 1/T1 contrast. This may be explained by the different B1 dispersion behavior of these two tissue types. 1/T1rho of fat is B1 field independent, whereas 1/T1rho of muscle decreases clearly with increasing B1 field. In conclusion, 1/T1rho provides a useful tool in manipulating contrast in magnetic resonance imaging of diseased muscle.

Gyrate atrophy of the choroid and retina with hyperornithinaemia (GA), an autosomal recessive disease, affects skeletal muscle in addition to the eye. Muscle biopsy samples show prominent type 2 muscle fibre atrophy. Atrophic fibres also contain accumulations of tubular aggregates in electron microscopy. To evaluate skeletal muscle involvement in detail, the thigh muscles of 7 patients with GA were examined using semi-open conchotome muscle biopsies, computed tomography (CT) and ultralow-field magnetic resonance imaging (MRI) at 0.02 T. In MRI, the T1 and T2 proton relaxation times were measured. Type 2 muscle fibre atrophy was found in all biopsy samples (100%) and tubular aggregates in 6 of the 7 samples studied (87%). The CT density of the muscle tissue was increased in the only child of the study, decreased in 3 elderly subjects, and normal in the remaining 3 patients. Mean T1 relaxation times of the patients were decreased (135 +/- 5 ms) as compared to those of 6 healthy controls (157 +/- 12 ms) (p = 0.002). The T2 relaxation time was slightly increased (40 +/- 3 ms) as compared to the controls (35 +/- 7 ms; not significant, p = 0.3). Our findings suggest that the thigh muscles of the patients with GA universally show changes in CT and MRI studies, but relaxation time measurements gave little additional information on the muscle metabolism.

Rationale and Objectives. Tendon xanthomas are atherosclerotic plaquelike collections of lipids that develop with age in the Achilles tendons of patients having familial hypercholesterolemia (FH). We tested a fat—water discrimination technique for imaging Achilles tendon xanthomatosis. Methods. We used the spin-warp imaging technique optimized for low-field magnetic resonance (MR) imaging to obtain separate fat and water images of the Achilles tendon. Seven patients with FII, two patients with normal tendons, and three patients with other tendon pathology were studied. Results. Normal tendons showed an intensity near or equal to that of the noisy background in all images. Compared with the background, the intensity of the FH tendons was approximately fivefold greater in magnitude images, fourfold in fat images, and 10-fold in water images. Conclusion. The method sensitively detected even subtle xanthomatosis in young patients, but differentiation of xanthomas from other pathologic lesions was possible with this method only when the tendons were significantly thickened.

Experimental myonecrosis-induced by injection of notexin into rat tibialis anterior muscle and subsequent regeneration were studied from 1 h to 21) days postinjury with magnetic resonance imaging using conventional and magnetization transfer sequences, and these findings were correlated with histopathology. MR images revealed necrosis within 1 h postinjection. Histopathologically, necrotized fibers enlarged and intercellular spaces widened, indicating intracellular and extracellular edema, which began to decrease after 48 h, whereafter the formation of new myofibers predominated. T 2 increased progressively until 7.5 h, while T 1 increased until 24 h. Magnetization transfer contrast (MTC) and magnetization transfer rate (R wm ) decreased rapidly postinjection; the decrease in R wm lasted longer than in MTC (96 h versus 48 h, respectively). Spin echo, inversion recovery and magnetization transfer sequences revealed the lesions equally effectively. MR images and relaxation parameters reflect well the extent of histopathological injury and edema in the acute phase, whereas specific tissue changes in the regenerative phase were not detectable by MRI. MT imaging and especially magnetization transfer rate are as sensitive as conventional T 2 contrast to alterations in water imbalance

Patients with heterozygous familial hypercholesterolaemia (FH) are at high risk for the development of coronary artery disease. Achilles tendon xanthomata are often the first clinical manifestation of FH, but are seldom palpable earlier than during the third decade. Twenty-one FH children aged 3-18 years underwent high-frequency ultrasound examination of the achilles tendon. Hypoechoic infiltration of the normal tendon structure was demonstrated in 8 of 21 (38%) of the FH children. The findings were similar in boys and girls. Control subjects (n = 68) aged 1-25 years had no sonographically detectable tendon abnormalities. The thickness of the achilles tendon of the FH children was (mean +/- SD) 7.1 +/- 1.5 mm (range 5-10 mm). The respective values for the controls were 5.8 +/- 1.0 mm (3-7 mm. We conclude that ultrasound examination sensitively detects cholesterol accumulation in the achilles tendon of FH children before tendon xanthomata are clinically evident.

The feasibility of magnetic resonance imaging and the magnetization transfer technique for measurement of diurnal fluid changes in lumbar discs was studied with the use of 13 healthy subjects. The diurnal height loss of the subjects ranged from 13 to 21 mm. The disc signal in T2-weighted magnetic resonance imaging increased as much as 25% after overnight bed rest, presumably due to the enhanced influx of water. The change in magnetization transfer parameters also suggested increased hydration of the disc after bed rest. Magnetic resonance imaging techniques can be used for indirect measurement of the changes in fluid content and the interaction of water with macromolecules in the disc.

Preoperative and postoperative magnetic resonance imaging (MRI) of the lumbar spine was performed on 41 patients treated either microsurgically or with percutaneous nucleotomy for lumbar disc herniation. On the first postoperative day, MRI revealed an edematous mass effect at the level of surgery in 25 (61%) patients. The mass effect caused compression of the anterior dural sac mimicking preoperative disc herniation. After the follow-up of 6 months, the mass effect had disappeared in all patients, and the MRI finding in the operated disc space was that of a prolapse in six (15%) patients and that of a protrusion in 16 (39%) patients. Postoperative scarring was detected in 23 (56%) patients. The amount of the epidural scar tissue was significantly (p = 0.0002) associated with the extent of the early postoperative hemorrhagic changes detected in these patients with MRI. No association was observed between these MRI findings (mass effect, disc herniation, epidural scarring) and the clinical outcome of the patients.

We evaluated the incidence of postoperative extradural hematomas by means of magnetic resonance imaging (MRI) technique in 44 patients who underwent successful surgery for a virgin lumbar disc herniation. Of these patients, 28 were treated with microdiscectomy and 16 with percutaneous nucleotomy. Postoperative hematoma proved to be a universal MRI finding in the microsurgically treated patients: hematomas were found in all patients in the microdiscectomy group. In 12 (43%) patients the hematoma extended into the dural sack. The incidence of hematomas was significantly (p = 0.001) lower in the patients treated with percutaneous nucleotomy: hematomas were detected in only 10 (63%) of the 16 patients in the nucleotomy group. The hematomas in these patients were also smaller in size and none of them connected with the dural sac. Correlation between the hematomas and clinical findings showed that the presence of a hematoma had no obvious effect on the immediate postoperative recovery of a patient.

RATIONALE AND OBJECTIVES The variation of measured magnetic resonance T1 relaxation times of autopsied human muscle samples is confusing. Hence, the authors studied rats' muscles to evaluate the effect of fiber type, the relative area of nonmyofiber space, fat and water content, cell death, and the mechanism of death on proton T1. METHODS Rats were studied on a 0.1 T magnetic resonance device. We studied how death by cervical dislocation, pentobarbital injection, or a combination of these methods, as well as the amount of time lapsed after death, variably affected T1. RESULTS Death itself did not affect T1, but the mechanism of death did: rats killed by cervical dislocation after ether anesthesia had longer T1 than those killed with an overdose of pentobarbital. T1 was significantly shorter 1 day after death than at 4 hours after and returned to baseline levels within 4 days after death. Repeated warming caused variation in T1 and obscured other possible changes. CONCLUSIONS Investigation methods should be strictly controlled and standardized before measurements of the relaxation time, T1, of muscle tissue will provide consistent results.

To analyze in vivo brain creatine (Cr) content in gyrate atrophy of the choroid and retina with hyperornithinemia (GA).GA is caused by inherited deficiency of ornithine-delta-aminotransferase activity. Patients lose their vision by middle age and develop selective atrophy of type II skeletal muscle fibers. As demonstrated by MRS, the patients' skeletal muscles have diminished stores of high-energy Cr phosphate. Minor structural and electrophysiologic abnormalities in the brain of these patients also imply that the CNS may be affected.The authors acquired proton MR spectra of the basal ganglia of 22 healthy control subjects and 20 GA patients. Nine patients received supplementary Cr or its precursors, and one child was on an arginine-restricted diet to normalize plasma ornithine concentration. The ratios of N-acetylaspartate (NAA) to Cr, NAA to choline (Cho), and Cho to Cr, and the ratios of NAA, Cho, and Cr to tissue water were calculated.NAA/Cr (Cho/Cr) in the untreated and treated patients and control subjects were (mean +/- SD) 3.3+/-0.4, 2.0+/-0.4, and 1.5+/-0.7 (1.9+/-0.3, 1.3+/-0.4, and 0.9+/-0.2), indicating that Cr content in untreated GA patients was proportionally and markedly diminished, and partially corrected by therapy (p0.0001). NAA/Cho was similar in all three groups. Cr/water in the untreated patients was only 46%, and increased to 75% of the control ratios in the treated patients (p0.0001).Hyperornithinemia-associated Cr deficiency in GA also affects the CNS, further supporting the possibility that Cr deficiency also has a pathogenetic role in the retina. The deficiency was partially corrected by Cr supplementation and an arginine-restricted diet.

Red blood cell aggregates are mainly responsible for the echogenicity of flowing blood. Thus, ultrasound can be used to observe the degree of red blood cell aggregation in slow flow conditions. We quantified blood echogenicity to study aggregation tendency of red blood cells in blood of patients with claudication, patients with suspected venous thrombosis, and normal volunteers without and with in vitro addition of naftidrofuryl (10(-6) M). Normal volunteers showed lower original echogenicity than any group of patients, and claudication patients showed the highest echogenicity. Naftidrofuryl caused a fall in mean echogenicity in all groups, and its effect was pronounced on blood samples with a high original echogenicity.

We assessed in this study the potential development of postoperative muscle atrophy in the operation area in 39 patients treated by either microdiscectomy or percutaneous nucleotomy for lumbar disc herniation. The cross-sectional areas of the lumbar muscles were measured on magnetic resonance images created on the day preceding the operation and 6 months postoperatively. The cross-sections of the lumbar muscles remained unchanged during the observation period in all treated patients indicating that no muscle atrophy had developed in the operation area. Since peroperative tissue trauma may correlate with subsequent muscle denervation and atrophy, this finding may be due to the tissue sparing nature of microdiscectomy and percutaneous nucleotomy, thus encouraging the use of these techniques in the treatment of lumbar disc herniation.

Objectives. Tendon xanthomas cause thickening of the tendon and are an important sign in monogenic familial hypercholesterolaemia (FH). The aim of our study was to investigate the usefulness of achilles tendon sonography in detecting FH patients. Special attention was paid to structural abnormalities of the achilles tendon. Design. A clinical study with methodological testing. Setting. Patients suspected of having FH were sent to the out-patient Department of Medicine from other departments of Turku University Central Hospital and from primary care units. The patients were studied by high-frequency ultrasound before more exact typing of the lipid disorder. An additional study of normolipidaemic volunteers and a phantom study were also carried out. Subjects. Forty FH patients, 51 non-FH hypercholesterolaemia patients and 41 normolipidaemic volunteers were included in the study. Main outcome of measures. The thickness of the tendon was measured and the tendon structure and its echogenicity were recorded. Results. Twenty-five out of 40 (63%) FH patients had distinctly thickened tendons (men more than 10 mm, women more than 9 mm). Thirty-six (90%) had a typical structural alteration of low or mixed echogenicity of the tendon. Three non-FH patients were found to have xanthomas on sonography. Conclusions. We conclude that ultrasonography is a sensitive method of detecting xanothomas that reveals the altered tendon structure even in xanthomatous tendons of normal thickness.

A reconstructed separate fat image was used for studying the fat content of the liver of 12 dead and six living fasting burbots (Lota lota) in a 0.04 T magnetic field with olive oil as a reference. The correlation between the MR intensities and the results of the cytological, histological and chemical fat measurements, as well as chemically measured water, collagen and total protein contents were examined. The MR signal intensity in reconstructed fat images correlated well with the changes in fat content of the liver in living fish (r = 0.69, P = 0.0014). Also the contents of water (r = -0.66, P = 0.003) and total protein (r = -0.91, P = 0.013) correlated significantly with the MR signal intensity. The reconstructed fat image is thus a reliable method for following the changes in tissue fat content. The living burbot is an applicable test animal for studying the hepatic fat content with MR.

Twenty-two patients with acute abdominal symptoms were studied by abdominal sonography and by sonographically guided aspiration of intraperitoneal fluid. The colour of the fluid was found to be diagnostically valuable: a green colour indicated gallbladder perforation, a yellow colour was found in a variety of infectious diseases, a red colour in haemorrhagic pancreatitis or haemorrhage. Aspirating fluid from the peritoneal cavity under ultrasound guidance in connection with any routine ultrasound examination is a valuable and easy method for studying patients with symptoms of acute abdomen.

The accuracy of plain films, excretory urography and ultrasound for the clinical work-up of renal colic for detecting urinary calculi was evaluated prospectively in 49 patients. Excretory urography was the most sensitive and specific test. Plain films and sonography each had a sensitivity of approximately 60%, but combined yielded a sensitivity of 80%; specificity did not improve. A diagnostic algorithm where sonography was performed first followed by an excretory urography in case of a negative sonography was highly sensitive (93%) and rather specific (79%). This algorithm appears also to have a good cost-benefit rate.

Magnetic resonance imaging (MRI) was performed on 35 young competitive gymnasts and 10 control subjects in order to detect the number of degenerated discs and other lumbar spinal disorders. Lumbar radiographs were obtained from all gymnasts who showed evidence of disc abnormality on MRI. Eleven gymnasts had suf fered from episodes of low back pain during exercises and eight were found to have evidence of back trauma. Only 3 of the 35 gymnasts had MRI evidence of degen erated discs associated with Scheuermann's manifes tations and spondylolysis. Lumbar radiographs con firmed the diagnosis in these three cases. The results indicate that despite the excessive range of motion and strong axial loading of the lumbar spine that are asso ciated with gymnastic maneuvers, incurable primary damage to the intervertebral discs is uncommon in young gymnasts dunng growth.

Both normal and experimentally hydronephrotic rabbits were imaged at 0.02 T using partial saturation (PS 160/30) and inversion recovery (IR 1000/200/40) sequences. The signal intensity of normal renal medulla and cortex markedly increased after the injection of 0.1 mmol/kg of Gd-DOTA. In the unilateral total hydronephrosis the dilated renal pelvis did not contrast enhance after 15 and 35 min of Gd-DOTA injection. The enhancement pattern was similar in 1- and 3-week-old hydronephrosis. The effect of Gd-DOTA on renal T1 times at 0.02 T was studied using rats. Fifteen minutes after the Gd-DOTA injection (0.1 mmol/kg) the T1 times of excised rat kidneys decreased from 311 to 90 ms. The authors conclude that the enhancement of the MR signal of the kidney by Gd-DOTA at an ultralow magnetic field (0.02 T) is similar to its enhancement at higher fields (greater than 0.15 T).

Comparison of the radiographic signs of Scheuermann disease and the corresponding disc degeneration on thoracolumbar magnetic resonance (MR) images was made in 21 young patients. Marginal sclerosis, Schmorl nodes and narrowed disc spaces, but not irregular or wedge-shaped end-plates, were significantly associated with disc degeneration. Fifty-five percent of the discs in the patients with Scheuermann disease were abnormal on MRI, compared with 10% in asymptomatic controls. Our study confirms that thoracolumbar disc degeneration is enhanced in 20-year-old patients with low back pain who have radiological evidence of Scheuermann disease.