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C Baratti

Publications and source records attributed to C Baratti.

At least 19 recordsLinked to original sources
PubMed1999

Comparative MR imaging study of brain maturation in kittens with T1, T2, and the trace of the diffusion tensor.

PURPOSE: To assess the time-course of the relaxation times and the orientationally averaged water diffusion coefficient Doav in postnatal brain development. MATERIALS AND METHODS: Multisection maps of T1, T2, and the trace of the diffusion tensor (Trace[D] = 3 x Doav) were obtained in four kittens at eight time points. RESULTS: In the adult, Doav was about 700 micron 2/sec in both white and gray matter. In the newborn, Doav was 1,100-1,350 micron 2/sec in white matter and 1,000 micron 2/sec in gray matter. For all anatomic regions and time points, the correlation between Doav and 1/T2 was high (R2 = 0.87, P << .001). T1 showed a lower correlation with Doav and a higher sensitivity to myelinization than did T2. CONCLUSION: Although Doav shows dramatic changes in the maturing brain, the high correlation between Doav and T2 indicates that little additional information can be obtained by measuring this diffusion parameter during normal brain development. This contrasts with previous findings in brain ischemia, where Doav and T2 appear to be uncorrelated. After including the authors' data and published iontophoretic measurements in a simple model of diffusion in tissues, the authors suggest that the underlying mechanisms of Doav reduction in brain maturation and ischemia are different. Doav changes during development are mainly affected by events occurring in the cellular compartment, while changes in extracellular volume fraction and tortuosity, which are thought to determine the reduction in Doav during ischemia, are probably of secondary importance.

Animals↗
PubMed1998

Intraobserver and interobserver variability in schemes for estimating volume of brain lesions on MR images in multiple sclerosis.

PURPOSE: Our goal was to evaluate the intraobserver and interobserver reproducibility of measurements of brain lesion load in multiple sclerosis (MS) by using two proposed acquisition schemes. METHODS: Three-millimeter-thick conventional spin-echo (CSE) and fast fluid-attenuated inversion-recovery (FLAIR) sequences were obtained and the lesions segmented using a semiautomated technique based on local thresholding to calculate intraobserver and interobserver reproducibility. These were compared with images obtained from two separate MR units in which 5-mm CSE sequences were obtained and segmented by using the local thresholding technique and also by manual outlining. RESULTS: The intraobserver coefficient of variation was 4.0% (95% confidence interval [CI], 3.0% to 4.5%) for the 5-mm CSE sequence measured with manual outlining, 3.1% (95% CI, 2.5% to 3.2%) and 5.1% (95% CI, 4.1% to 5.6%) for the two sets of 5-mm CSE sequences measured using the local thresholding technique, 5.7% (95% CI, 3.9% to 6.6%) for the 3-mm CSE sequence, and 2.6% (95% CI, 2.1% to 2.7%) for the fast FLAIR sequence. The interobserver coefficient of variation was 7.1% (95% CI, 4.9% to 8.7%) and 8.3% (95% CI, 6.4% to 9.6%) for the two sets of 5-mm CSE sequences, 7.3% (95% CI, 4.7% to 9.1%) for the 3-mm CSE sequence, and 2.9% (95% CI, 2.3% to 3.3%) for the fast FLAIR sequence. The intraobserver and interobserver reproducibility of measurements obtained with the fast FLAIR technique was significantly better than those obtained with the other techniques. CONCLUSIONS: Our data indicate that the intraobserver and interobserver variability in quantifying MS lesions can be reduced significantly with the use of fast FLAIR sequences, while no significant improvement is gained by reducing the section thickness from 5 mm to 3 mm.

Adult↗
PubMed1996

A spinal cord MRI study of benign and secondary progressive multiple sclerosis.

This study was performed to achieve a better definition of the nature of the disability in multiple sclerosis (MS). Axial spinal cord magnetic resonance imaging (MRI) at C5 was obtained in 15 patients with benign MS, 17 patients with secondary progressive MS and 10 healthy controls. Patients with secondary progressive MS had smaller spinal cord cross-sectional area (P = 0.01) and transverse diameter (P = 0.006) than patients with benign MS. The degree of disability was inversely correlated with both the cross-sectional area (r = -0.6, P = 0.0018) and transverse diameter (r = -0.5, P = 0.0032) of the cord. Spinal cord atrophy was found in 7 (41%) patients with secondary progressive MS and in 2 (13%) with benign MS. These findings suggest that destructive pathology within MS lesions might play a relevant role in the development of disability in MS.

Adult↗
PubMed1996

Quantitative assessment of MRI lesion load in multiple sclerosis. A comparison of conventional spin-echo with fast fluid-attenuated inversion recovery.

In this study, we compared a fast fluid-attenuated inversion recovery (fast-FLAIR) sequence to conventional spin-echo (CSE) in the evaluation of brain MRI lesion loads of seven patients with clinically definite multiple sclerosis. Interleaved CSE (3000/20, 5 mm contiguous axial slices) and fast-FLAIR (9000/150/2200, 5 mm contiguous axial slices) sequences were performed on a 1.0 T machine. Lesions were counted consensually by two observers and then segmented independently by two other observers using a local thresholding technique, with subsequent manual editing in the case of poorly defined lesions. Four hundred and two lesions were detected in at least one of the two sequences: 128 were seen only on fast-FLAIR, 17 only on CSE. Forty-one lesions were larger on fast-FLAIR, while no lesion was considered larger on CSE. The numbers of periventricular (P = 0.05), cortical/subcortical (P = 0.02) and discrete (P = 0.05) lesions detected using fast-FLAIR were higher than those detected using CSE. The median lesion load was 7185 mm3 on CSE and 8418 mm3 on the fast-FLAIR, the average being 18% (range = 11.6-29%) higher on the fast-FLAIR images. Lesion contrast ratio was higher for lesions on the fast-FLAIR than on the CSE sequence (P < 0.0001). The percentages of poorly defined lesions which needed manual editing after the local thresholding technique was applied and the total time needed for the measurements were lower (P < 0.001) when fast-FLAIR images were used compared with CSE. This resulted in a reduced inter-rater coefficient of variation in measuring lesion volumes. Our data indicate that fast-FLAIR sequences are more sensitive than CSE in detecting multiple sclerosis lesion burden and that fast-FLAIR is a promising technique for natural history studies and clinical trials in multiple sclerosis.

Adult↗
PubMed1995

Partially saturated fluid attenuated inversion recovery (FLAIR) sequences in multiple sclerosis: comparison with fully relaxed FLAIR and conventional spin-echo.

Fluid attenuated inversion recovery (FLAIR) sequences produce selective cerebrospinal fluid (CSF) suppression by employing a very long inversion time (TI). We used the FLAIR sequence to study patients with multiple sclerosis (MS) at 0.6 T. So far, a very long TR (and long acquisition time) has been used in a fully relaxed (FR-FLAIR) system. To speed up the FLAIR sequences, we used a shorter TR, and demonstrated that complete CSF suppression can be maintained with partial saturation (PS-FLAIR) by reducing TI at the same time. The introduction of partial saturation, however, reduced the contrast between lesions and normal appearing white matter (NAWM). Suboptimal CSF suppression therefore had to be accepted to maintain sufficient lesion to NAWM contrast. Using a TE of 60 ms, the PS-FLAIR and FR-FLAIR performed equally well in the detection of MS-lesions, although the former provided poorer CSF suppression. Both FLAIR sequences, however, provided poorer constrast between lesions and NAWM compared to conventional spin-echo sequences. Although the long acquisition time of the FLAIR sequence can be reduced by using partial saturation, complete CSF suppression and good lesion to NAWM contrast are incompatible at short TRs. Using a TE of 60 ms, conventional spin-echo sequences detect more lesions and provide better contrast between lesions and NAWM than FLAIR sequences in MS patients.

Brain↗
PubMed1995

Intra- and inter-observer agreement of brain MRI lesion volume measurements in multiple sclerosis. A comparison of techniques.

The measurement of MRI lesion load in multiple sclerosis is increasingly being used to evaluate the natural history of the disease and to monitor the efficacy of treatments. If, as might occur in multicentre studies, lesion load is measured by several observers in different patients or by the same observer in serial scans, it would be necessary to utilize a technique which provides results with high inter- and intra-observer agreements. This study was performed to evaluate the intra- and inter-observer agreement of semi-automated lesion volume measurement using thresholding, and to compare them with those obtained using an arbitrary scoring system (ASS) and a quantitative manual tracing method (MTM). Brain MRIs were obtained for 20 clinically definite multiple sclerosis patients and were evaluated independently by three observers. The median intra- and inter-observer agreements were, respectively, 88.5% (range 69.0-96.8%) and 79.0% (range 73.3-98.3%) using the ASS, 95.0% (range 85.1-99.4%) and 93.4% (range 77.3-98.3%) for the MTM, 96.3% (range 94.2-98.9%) and 93.7% (range 83.8-98.3%) for the semi-automated technique. The intra- and inter-observer agreements for the semi-automated technique increased to 98.5% (range 96.3-99.8%) and 96.1% (range 90.5-98.6%) when a consensus in the choice of threshold for lesion segmentation was reached. The intra- and inter-observer agreements were significantly greater for the semi-automated method compared with both the arbitrary scoring and the MTMs. The intra-observer variability for the semi-automated technique was significantly lower (P < 0.0001) than the inter-observer variability obtained using the same technique. These data indicate that it is possible to obtain high intra- and inter-observer agreements using a semi-automatic thresholding technique to quantify lesion volumes in multiple sclerosis. The technique may prove useful in multicentre studies, in which a single observer is still preferable.

Brain↗
PubMed1995

A magnetization transfer imaging study of normal-appearing white matter in multiple sclerosis.

We attempted to define the role of subtle changes in the normal-appearing white matter (NAWM) in the development of disability in multiple sclerosis (MS). Twenty-seven clinically definite MS patients with either relapsing-remitting or chronic-progressive courses and 10 sex- and age-matched controls entered the study. For each patient and control, we studied two NAWM areas in the frontal lobe with magnetization transfer imaging (MTI). For patients, we also calculated the MT ratios (MTRs) for three contiguous areas of NAWM progressively further from "isolated" lesions visible on conventional MRI. Frontal NAWM in MS patients had lower mean MTRs than the frontal white matter of the controls (p = 0.02). MTRs in the NAWM adjacent to isolated lesions increased with distance from them to the cortical gray matter (p = 0.04). This pattern was typical for patients with chronic-progressive MS whose MTRs in the first two regions of NAWM adjacent to lesions were lower than those of the same regions of patients with relapsing-remitting MS. This study confirms that there are alterations in the NAWM of MS patients and suggests that such changes might be relevant to the disability in MS.

Adult↗
PubMed1995

Acute transverse myelopathy: spinal and cranial MR study with clinical follow-up.

PURPOSE: To evaluate the contribution of MR in determining the cause of acute transverse myelopathy, to determine the frequency and types of the intracranial lesions detectable on MR at the onset of the disease, and to monitor clinical and MR evolution of the disease. METHODS: Spinal and cranial MR images were obtained for 30 patients with acute transverse myelopathy. Gadopentetate dimeglumine was administered in 10 patients. Mean follow-up time was 18 months. RESULTS: Spinal cord MR findings were abnormal in 14 of 30 patients. The abnormal MR can be divided into group A, in which one segment was involved (8 patients), and group B, in which more than one segment was involved (6 patients). In both groups there were 2 patients with enhancing lesions. Enhancement was less homogeneous in the group B patients. Enhancement did not change with increased length of lesion. At follow-up, the diagnostic categories of the patients were multiple sclerosis (8 patients), encephalomyelitis (1 patient), viral myelitis (3 patients), and myelopathy of unknown cause (18 patients). After the episode of acute transverse myelopathy, in 4 of 8 patients in group A and in 4 of 5 patients with normal spinal MR but abnormal brain MR findings clinical signs of multiple sclerosis developed. In no patients in group B did multiple sclerosis develop. The final diagnoses for the 4 patients with gadolinium-enhancing spinal lesions were myelopathy of unknown cause (2 patients), multiple sclerosis (1 patient), and viral myelitis (1 patient). CONCLUSION: MR contributed to establishing the diagnosis in 40% of our cases.

Acute Disease↗
PubMed1988

Prevention of wound dehiscence in severely obese patients with jejuno-ileal by-pass: the role of hyaluronic acid.

There is a high incidence of wound dehiscence, ranging from 6.9% to 22%, after surgery for severe obesity. Different surgical techniques to minimize this drawback of the operation have been proposed, but none have seemed to be really effective. A different approach to this problem has been tried using topical treatment with hyaluronic acid through the drains of the laparotomy suture. Twenty patients subjected to jejuno-ileal by-pass for severe obesity were randomized into two treatment groups: hyaluronic acid (80 mg/daily) or placebo (saline), for 5 days, starting at the operation. Granulation tissue was withdrawn from the wound through polyvinyl catheters 1, 3 and 5 days after the operation. It was processed for light, scanning and transmission electron microscopy. Ten days after the operation, the wounds were examined for dehiscence. Hyaluronic acid treatment reduced the incidence and degree of dehiscence macroscopically, increased the maturation of granulation tissue during the first post-operation days and stimulated fibroblasts to synthesize procollagen shortly after the operation.

Adult↗
PubMed1987

Prevention and early diagnosis of cancer in the rectal stump of ulcerative colitis patients after colectomy and topical treatment.

Ulcerative colitis with malignant degeneration and dysplasia can be a precancerous lesion. Therefore, it is necessary to prevent or, at least to diagnose as early as possible any development toward neoplasia in the colon or rectum of the colitis patients. The only reliable guide for a risk of malignant tissue degeneration is dysplasia of the mucosa. A group of 31 patients was studied after total colectomy with ileorectal anastomosis and subsequent topical treatment with enemas containing sulphasalazine and corticosteroids. Two of these patients had mild rectal dysplasia before surgery, seen in a biopsy specimen obtained endoscopically. All the patients were followed for a long time after surgery, with endoscopy and microscopic and ultrastructural observation of rectal biopsy material taken from different sites in the mucosa, both from areas that looked dysplastic by endoscopy and from those that appeared normal. The two patients with presurgical dysplasia, when examined later, one 12 months and one 18 months after surgery, had no rectal dysplasia; the mucosal covering was moderately complete and the anastomosis was functioning. It is considered that to prevent development of cancer in the rectal stump, colectomy should always be followed by regular topical treatment and there should be a check-up at short intervals for early diagnosis of any premalignant areas that might develop. Regression of such lesion was observed to lesser degrees after continuous treatment with the topical medication.

Adolescent↗
PubMed1986

Cytoprotection by PGE2, pirenzepine or vagotomy: a transmission and scanning electron microscopic study in rats.

We have studied the effects of PGE2, the anticholinergic pirenzepine and vagotomy on the rat gastric mucosa after challenge with ASA+0.15N HCl or absolute ethanol. The damage was evaluated by quantitative macroscopic examination, light and electron (transmission and scanning examinations) microscopy. We found both macroscopically and microscopically that pirenzepine and PGE2 were effective against ASA+0.15N HCl, but under microscopic examination they were seen to be uneffective 1 hr after absolute ethanol. Vagotomy showed some protection against ASA+0.15N HCl but was totally uneffective against absolute ethanol. The results stress the differences between ASA+0.15N HCl and absolute ethanol damage and show that "cytoprotection" is possible when the mucosa is challenged with noxious agents that do not act by hyperosmolar effects.

Animals↗
PubMed1986

Controlled study of the effects of tiropramide on biliary dyskinesia.

A controlled trial was carried out in patients with biliary dyskinesia to compare the effects of the new calmodulin-independent and antispastic drug tiropramide with those of imecromone. Forty patients were randomly divided into two groups, one treated with 300 mg tiropramide per day and the other with 1200 mg imecromone per day, both treatments lasting for 3 months. The results showed that tiropramide was significantly more effective in decreasing the number of attacks of pain and in improving pain and dyspepsia symptoms than imecromone. In subjects with delayed filling of the gall bladder during cholecystography, tiropramide but not imecromone was able to normalize the condition. These results confirm the antispastic synchronizing effect of tiropramide on the motor activity of the gall bladder and the sphincter of Oddi and indicate that it should be the drug of choice for treatment of motor disorders of the biliary tract.

Biliary Dyskinesia↗
PubMed1986

Topical treatment of experimental skin lesions in rats: macroscopic, microscopic and scanning electron-microscopic evaluation of the healing process.

The effects of the topical antiseptic agents mercurochrome and silver nitrate and of sodium hyaluronate on the process of wound healing were assessed by macroscopic examination, light microscopy histology, electron microscopy and scanning electron microscopy of wounds made by cutting or by abrasion of the skin of rats. It was found that wounds treated with hyaluronic acid underwent longer periods of inflammation (proportional to the presence of mastocytes) and greater amounts of collagen deposition than wounds that were either untreated controls or treated with silver nitrate or mercurochrome, but this did not impede the formation in the early stages of healing of bridges of fibrin between the edges of the wounds.

Administration, Topical↗
PubMed1986

Differential diagnosis of Crohn's disease of the colon from ulcerative colitis: ultrastructure study with the scanning electron microscope.

Mucosal biopsies from patients with Crohn's disease and with ulcerative colitis were studied by scanning electron microscopy. Important abnormalities of the mucosal surface were found in both diseases. For Crohn's disease, the characteristic abnormality was loss of the regularity of the polygonal units, but with preservation of the mucosal integrity and of the normal mucosal design. For ulcerative colitis, the abnormalities were disorganization of the cells, signs of sloughing, and superficial erosions. Patients with Crohn's disease always had a significantly increased number of muciparous cells, while those with ulcerative colitis had obvious signs of decreased mucus production. The lesions of ulcerative colitis could be seen under the scanning electron microscope in mucosal areas that appeared normal endoscopically. We feel therefore that scanning electron microscopy of biopsy specimens from patients with inflammatory bowel diseases can be of great help in differential diagnosis.

Colitis, Ulcerative↗
PubMed1985

Clinical evaluation of triletide versus antacids in the treatment of duodenal ulcer out-patients.

Thirty out-patients with endoscopically assessed, active duodenal ulcer of mild to moderate intensity were randomly assigned to 8-weeks' treatment with either antacids (0.8 g/day each of aluminium hydroxide and magnesium hydroxide), triletide (1.5 g/day) or a combination of the two treatments. Every other week, the intensity of subjective symptoms and of objective signs was scored and recorded, and the endoscopic outcome assessed at the 8th week. Three patients on antacids alone and 1 on triletide alone were withdrawn at the 4th week because of therapeutic failure. Symptoms and signs improved in the three groups significantly faster, to a significantly greater extent, and in more patients with triletide, alone or in combination, than with antacids. Endoscopic evidence of therapeutic response was detected in significantly more patients given triletide, alone or in combination, in comparison with the group who had antacids. A significant influence on promoting ulcer healing could be attributed to triletide (p less than 0.05, multiple linear regression) and not to antacids. Tolerance was complete in all patients. It is concluded that triletide appears to be equally well tolerated as, but significantly more effective than, antacids in relieving symptoms and promoting healing in patients with mild to moderate duodenal ulcer.

Adult↗