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The pre-prosthetic treatments of two female patients with osteoarthritis of the temporomandibular joints were presented in this paper. In the first case report, an 83-year-old patient wore complete dentures (CDs) for 30 years. The second patient (71 years of age) wore a three-year-old upper CD and a lower removable partial denture with a two-unit fixed dental prosthesis. Pain was successfully eliminated by the stabilization splint on the upper CD. Magnetic resonance imaging was used to confirm the diagnosis and clinical follow-up of the splint treatment.

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AIMS: The aim of the study was to compare the accuracy of A-scan biometry and MRI for the measurement of axial length in silicone oil-filled eyes. METHODS: This was a prospective randomised study of 70 patients. Biometry was performed using MRI in 33 patients (MRI group) and A-scan echography in 37 patients (A-scan group). The difference between predicted and final refraction was measured and evaluated statistically. RESULTS: In patients with axial length >/=26 mm, the mean deviation of the final from predicted refraction was -1.23 (SD 0.67) D in the MRI group and -2.3 (SD 2.02) D in the A-scan group. The difference between these two groups was statistically significant (p = 0.02). In patients with axial length <26 mm, the mean deviation of the final from predicted refraction was -0.12 (SD 1.29) D in the MRI group and -0.33 (SD 1.39) D in the A-scan group. There was no statistical significance between the two groups (p = 0.629). CONCLUSION: For highly myopic patients MRI biometry was a more accurate measurement of axial length in silicone oil-filled eyes. A-scan and MRI biometry were comparably accurate in measuring axial length in patients with axial length <26 mm.

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The association between oxidative stress and cardiovascular diseases is a widely accepted fact today. Generally, men have a higher risk of cardiovascular incidents and mortality from acute myocardial infarction and strokes. We have examined sport-associated circannual rhythms of oxidant and antioxidant processes by measuring plasma LPO, erythrocyte SOD, CAT, Gpx activity and plasma hormonal status in both sedentary and long-term trained men and women. We have shown seasonal variations in both oxidant and antioxidant status in all examined groups. The largest difference was observed in the oxidant status between sedentary men and women during autumn and winter, which is considered a period of high coronary risk for men. Sport decreased LPO in trained men in autumn, while the same effect in trained women was shifted towards summer. These data state that regular, long-term physical exercise training induces adaptive responses that confer protection against oxidative stress, as well as the beneficial effect of exercise with regard to season, particularly in men during a period of high coronary risk (autumn and winter, respectively) and in women during summer.

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Wild samples of Foeniculum vulgare Mill. (fennel) were collected from thirteen Italian localities at different latitudes and grown in field trials to evaluate their morphological and agronomic characteristics and essential oil compositions. All the parameters were recorded at full bloom stage, and the essential oils (obtained by steam distillation) were characterized by gas chromatography (GC) and GC/mass spectrometry (GC/MS). The morphological characteristics showed positive relations among the number of umbels per plant, the plant weight, and the umbel weight percentage, and between these three parameters and the oil content. The essential oils evidenced five chemical groups characterized by (1) alpha-phellandrene, methyl chavicol, and trans-anethole; (2) alpha-pinene, limonene, and trans-anethole; (3) methyl chavicol and alpha-phellandrene; (4) methyl chavicol and alpha-pinene; and (5) alpha-phellandrene.

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Two cases of rare adrenal cavernous hemangiomas are reported, one imaged with conventional X-ray techniques, US, CT, and MRI, and the other with US and CT. The CT technique clearly demonstrated calcifications and the internal structure of the lesions in both cases and peripheral rim enhancement on the postcontrast scan in one patient. Although MRI demonstrated accurately the complex nature of the lesion, the inability to visualize the calcified areas do not allow to make a specific histologic diagnosis.

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A prospective study of the possibilities and achievements of ultrasonography of the adrenal glands is presented. The adrenal glands of 146 patients with abnormalities suspected clinically were examined with ultrasound. Patients were also evaluated with computed tomography where there are firm criteria for the evaluation of adrenal pathology. Positive findings were detected by ultrasound in 46 patients, whereas computed tomography disclosed pathologic changes in 65 patients. In 81 patients, the finding of computed tomography was normal. With ultrasound, false positives were obtained in 3 cases and false negatives in 19 cases (14 hyperplasias, 5 tumors). Ultrasound findings were additionally compared with angiographic and clinical tests as well as with pathohistologic results of surgery and autopsy.

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The appearance of the normal penis and of a variety of penile abnormalities on magnetic resonance (MR) images was studied in 55 patients with either medium (0.35 T) or high (1.5 T) magnetic field strengths. Penile morphologic characteristics with anatomic detail of the corpora cavernosa and corpus spongiosum were demonstrated in each patient. MR images clearly displayed congenital anomalies (n = 6), penile prostheses (n = 7), fibrous tissue or hematoma due to trauma (n = 8), and fibrous plaque in Peyronie disease (n = 3). MR imaging also demonstrated urethral (n = 6) and penile (n = 5) neoplasms and allowed tumor staging, thus facilitating the surgical approach.

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The use of magnetic resonance (MR) imaging in the detection and staging of renal neoplasms was investigated in 104 patients with 106 renal cell carcinomas confirmed at surgery or autopsy. Overall, MR imaging demonstrated 101 of 106 lesions (95%), including all 93 tumors that were larger than 3 cm in diameter but only eight of the 13 smaller tumors (62%). MR imaging enabled accurate staging of 82% of all detected lesions but led to the understaging of nine lesions and the overstaging of nine. At present, MR imaging cannot be used as a screening modality for renal tumors. However, its negative predictive values of 98% and 99%, respectively, for the evaluation of tumor vascular extension and tumor spread to adjacent structures makes it an excellent staging modality that should be used when the CT findings are equivocal. MR imaging is not accurate in indicating bowel and mesentery involvement, but rapid technical advances and the introduction of bowel contrast medium may improve this present limitation.

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The diagnostic value of MR contrast between renal cortex and medulla (CMC) as an indicator of renal disease was retrospectively studied in 51 patients (9 patients with obstructive disease, 7 with inflammatory disease, 12 with various noninfectious parenchymal medical disease, 5 with vascular disease, 2 with diffuse neoplastic disease, 7 with hemosiderosis, and 10 with renal trauma [blunt trauma and 9 postlithotripsy]). Additionally, normal kidneys from 20 control subjects were studied. On T1-weighted spin-echo images (SE 500/30), CMC was visible in all the normal kidneys (19% contrast +/- 2% SD). A decrease in or an absence of CMC on T1-weighted images (SE 500/28) was found to be a sensitive but nonspecific sign in most of the renal diseases studied. CMC was visibly preserved at normal levels in 7 of the 9 kidneys traumatized by lithotripsy and in all 4 kidneys with acute renal obstruction; CMC was above normal in kidneys with hemosiderosis. In conclusion, alteration in CMC is a sensitive but nonspecific indicator of renal disease. Furthermore, normal CMC can be seen in the presence of renal pathology.

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Accuracy of ultrasonography (US), quantitative scintigraphy, and magnetic resonance (MR) imaging in diagnosis of acute renal allograft rejection was studied in 46 patients who underwent renal biopsy. Thirty-three patients had acute rejection; six, cyclosporine nephrotoxicity, as shown by biopsy, clinical findings, and follow-up study; two, acute tubular necrosis; and five, normal biopsy findings and renal function. Accuracy in demonstrating rejection was 72% for US and 75% for scintigraphy, indicating no significant difference between the two. MR imaging was significantly more accurate, reaching a level of 98%. However, accuracy of MR in demonstrating acute tubular necrosis in a larger number of patients is not known, and its accuracy in indicating recurrent glomerulopathy or infectious disease has not been addressed. The definitive role of MR in evaluating posttransplant renal failure is currently not established, but because of its high sensitivity in detecting renal abnormality, MR can be used for cases when results of US or scintigraphy are equivocal or contradict clinical impressions or when biopsy cannot be performed for medical reasons.

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Magnetic resonance (MR) imaging was performed in two groups of patients to determine its usefulness in evaluating fluid-containing renal masses deemed complex with computed tomography (CT). Twenty-two patients in group 1 had indeterminate renal masses by CT, five of which were also indeterminate by ultrasound (US). The results in this group were compared with histologic findings. Group 2 consisted of 20 patients with simple renal cysts diagnosed according to rigid CT criteria. On MR imaging, 11 of the 23 masses in group 1 and 19 of the 20 in group 2 were diagnosed as benign cysts. Fluid within the cyst had long T1 and T2, resulting in a low signal intensity on T1-weighted images. In the 12 remaining lesions in group 1 and in one lesion in group 2, the fluid content was indeterminate and MR did not permit differentiation of cystic renal carcinoma from old hemorrhage or adenoma. When fluid within the cystic mass did not have the MR characteristics of simple fluid, MR was not helpful in characterizing the mass, but when the fluid intensity was similar to normal urine, the cyst was benign.

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MR images of the male pelvis in 55 subjects were analyzed retrospectively for depiction of the zonal anatomy of the prostate gland as related to different repetition (TR) and echo (TE) times, slice thickness, plane of imaging, chronologic age of the patient, and different magnetic field strengths. With imagers operating at 0.35 and 1.5 T, T2-based tissue-contrast images were needed for the demonstration of the internal anatomy of the prostate gland. The display of zonal anatomy was improved when continuous 0.5-cm slices were used. Evaluating sequential sections, the peripheral, central, and transition zones could be differentiated. The peripheral zone showed higher signal intensity than either the central or transition zone and was discerned in the coronal, sagittal, and transverse planes. The central zone was of low signal intensity and was well displayed in the coronal and sagittal planes. The central zone was seen in 31 of the 32 young men (aged 25-35 years) but in only eight of the 23 older men (aged 40 years and older). The transition zone had intrinsic MR parameters similar to the central zone, and the two could be distinguished from each other only by the knowledge of their respective anatomic location. The low-intensity transition zone blended with the periurethral glands and the preprostatic sphincter. The transition zone was of homogeneous low signal intensity in young men but varied in size and signal intensity in older men. Such a detailed display of the prostate zonal anatomy offers a unique potential for the evaluation of prostatic physiology and disease.

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Paramagnetic metal chelates including Fe-EDTA, Fe-CDTA, Fe-DTPA, and Gd-DTPA were compared as intravenous urographic contrast agents for magnetic resonance (MR) imaging in rats. Each compound, administered intravenously at three different doses (0.05, 0.1, and 0.2 mmol./kg.), was rapidly excreted through the kidneys yielding renal signal enhancement between 5 min. and 50 min. after injection. Gd-DTPA was most effective vor the enhancement of the renal parenchyma and pelvis. Lesser enhancement was achieved by administration of Fe-CDTA followed by Fe-EDTA and Fe-DTPA. Enhancement of skeletal muscle and liver parenchyma could not be achieved with any of the compounds included in this study. We conclude that the iron chelates mentioned above are less effective as urographic agents for MR imaging than Gd-DTPA.

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Albumin is a macromolecule that remains largely confined to the vascular space after intravenous administration. Human serum albumin was paramagnetically labeled by covalently binding from nine to 18 gadolinium-DTPA (diethylenetriaminepentaacetic acid) chelates per protein molecule. This conjugate was tested in varying doses for in vivo biodistribution and effectiveness in tissue relaxation. After intravenous injection of the agent in rats, T1 relaxation times were significantly reduced in samples of the blood and in lung, heart, spleen, kidney, and brain tissue. These effects persisted at a relatively constant level for the next 30 minutes. In vivo magnetic resonance imaging of the heart and lungs of rats and rabbits confirmed the prolonged contrast-enhancing effect of the labeled albumin. These preliminary studies indicate that paramagnetically labeled macromolecules that distribute in the intravascular space may be effective for MR imaging evaluation of tissue blood volume.

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