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T Papaioannou

Publications and source records attributed to T Papaioannou.

29 records · Page 2Linked to original sources
PubMed1983

The influence on the spine of leg-length discrepancy after femoral fracture.

We investigated the spines of 15 patients who had significant leg-length inequality as a result of femoral shaft fractures sustained after skeletal maturity but below the age of 21 years. The patients were examined at least 10 years after fracture. The spines were studied clinically and radiographically before and after correction of leg-length inequality with a shoe-raise. Lateral spinal flexion was measured from radiographs. The lumbar scoliosis associated with the leg-length inequality was compensatory: after equalisation of leg-length the overall curve and the axial rotation were corrected completely. There was also an equal range of lateral flexion to either side after correction. Minor malalignments of the whole spine remained despite correction of the compensatory scoliosis, and within the lumbar spine correction of the scoliosis had not occurred equally at all levels. No patients complained of significant discomfort and neither structural abnormalities nor degenerative changes were seen on the radiographs.

Adolescent↗
PubMed1982

Arthrodesis of the wrist in rheumatoid disease.

Twelve cases of wrist fusion for rheumatoid disease have been assessed pre and postoperatively in terms of symptoms, function, union, and complications. Improvement in hand function can be attributed to the provision of a painless stable wrist, and fusion in the straight position is in no way detrimental to personal hygiene. Delayed wound healing and pin migration are not uncommon complications but do not affect the end-results, which is radiological union from third metacarpal to radius - a definitive situation.

Arthritis, Rheumatoid↗
PubMed1982

Scoliosis associated with limb-length inequality.

We reviewed the records and physical findings of twenty-three young adults who had had significant untreated limb-length inequality, present since childhood. The spine was studied radiographically and clinically before and after neutralization of the discrepancy of limb lengths with a lift. Movements of the spine also were measured. A significant asymmetry of lateral flexion of the spine remained in nearly all of the patients after neutralization of the discrepancy. The lumbar scoliosis associated with the limb-length inequality was compensatory and non-progressive, but abnormalities of the Cobb angle and of axial rotation remained in the young adults. No relationship was found between the underlying cause of the anisomelia or its duration and the severity of the spinal abnormality. The scoliosis was minor in patients with discrepancies of less than 2.2 centimeters. No patients complained of significant discomfort in the back, nor were degenerative radiographic changes evident there.

Adolescent↗
PubMed1980

Idiopathic carpal tunnel syndrome caused by carpal stenosis.

Computed tomography was used to measure the cross-sectional area of the carpal canals in normal controls of both sexes and in women with idiopathic carpal tunnel syndrome. The women controls had significantly smaller carpal canals than the men controls both proximally and distally. In the patients both the proximal and distal cross-sectional areas were significantly reduced compared with the women controls. The measurements showed that carpal canal stenosis is associated with idiopathic carpal tunnel syndrome, narrowing of the canal is bilateral in patients who have unilateral symptoms, and narrowing is greater in the proximal carpal canal. There was no correlation between age and the size of the canal. The difference in the size of the carpal canal between normal men and women might explain the tendency of women to develop carpal tunnel syndrome. The lack of correlation between age and the size of the canal suggests that stenosis of the carpal canal is inherited rather than acquired. Symptoms arise only later in life, when degenerated changes in the content or the walls of the carpal canal compete with the median nerve for space and its function becomes impaired by compression.

Adult↗
PubMedDate not supplied

Biliary lithotripsy as an adjunct to laparoscopic common bile duct stone extraction.

We investigated various energy sources and delivery systems suitable for fragmentation of common duct calculi by a laparoscopic technique. We evaluated electrohydraulic lithotripsy (EHL) using 1.9-Fr probe delivering 80 W and laser lithotripsy using a 200-micron(s) fiber delivering 30-70 mJ/pulse at 5-20 Hz. In vitro biliary stone fragmentation analysis suggested that the laser lithotripsy produced a more controllable fragmentation than EHL. Initial attempts to employ EHL techniques in animal models resulted in common bile duct injury or inadequate fragmentation of stones. In contrast, biliary lithotripsy was accomplished in pigs using the pulsed-dye laser at 10 Hz and 60 mJ/pulse. Histologic evaluation revealed no evidence of ductal injury related to laser stone fragmentation. Subsequently, laser common duct lithotripsy was used in two human subjects. One patient had a 1.8-cm impacted ampullary stone and one patient had a 3-cm intrahepatic stone. In both cases, the stones were removed laparoscopically after laser fragmentation. Our experience suggests that the laser lithotripsy may facilitate laparoscopic common duct stone extraction procedures.

Adult↗
PubMedDate not supplied

Arterial stiffness in type 1 diabetes mellitus is aggravated by autoimmune thyroid disease.

OBJECTIVE: The aim of our study was to measure arterial stiffness in patients with Type 1 diabetes mellitus, its contributing factors and its relation to macrovascular arterial changes. MATERIALS AND METHODS: Thirty-one female Type 1 diabetic patients were studied; 11 had concomitant autoimmune thyroid disease although euthyroid during the study period. Stiffness was studied using applanation tonometry and pulse wave analysis for evaluation of systolic arterial pressure augmentation secondary to arterial stiffening and early wave reflection. Results were compared to 24 healthy individuals. In all patients, endothelium-related flow-mediated dilation (FMD) of the brachial artery and intima-media thickness (IMT) of the carotid artery were measured. RESULTS: Augmentation pressure (AP) and augmentation index (AI) were higher in Type 1 diabetic patients suggesting stiffer arteries compared to controls (AP: 5.8 +/- 3.6 vs 2.8 +/- 2.2 mmHg, p < 0.001; and AI:18.3 +/- 9 vs 11.1 +/- 8.8%, p = 0.004). The subgroup of diabetic patients with autoimmune thyroid disease presented stiffer arteries than those without (AP: 6.5 +/- 2.9 vs 5.5 +/- 3.9 mmHg, p < 0.05; and AI: 21.3 +/- 5.4 vs 16.7 +/- 10.3%, p < 0.05), though the two groups did not differ statistically by means of age, disease duration, hemoglobin A1c (HbA1c), lipid levels, FMD and IMT. In multiple regression analysis, variables independently associated to AI in the diabetes group were: age (p = 0.028), IMT of the carotid artery bifurcation (p = 0.045), disease duration (p = 0.031) and autoimmune thyroid disease (p = 0.015). No correlation was observed between AI and metabolic control, blood pressure, microalbuminuria, presence of retinopathy and endothelial function (FMD). CONCLUSIONS: Women with Type 1 diabetes have increased arterial stiffness, which indicates macroangiopathy. An independent correlation between these indices and carotid IMT was observed. Concomitant autoimmune thyroid disease seems to aggravate arterial compliance in these patients, a finding that merits further investigation.

Arteries↗
PubMedDate not supplied

One-year results of excimer laser photorefractive keratectomy for myopia.

BACKGROUND: Excimer laser photorefractive keratectomy for the correction of myopia is presently under investigation in the United States by the Food and Drug Administration (FDA). The Phase II-B FDA study is being conducted on 75 normally sighted myopic eyes utilizing three currently available excimer lasers. This report presents the 1-year results on 12 myopic eyes treated with the VISX excimer laser system at the Ellis Eye Center at Cedars-Sinai Medical Center in Los Angeles under the Phase II-B FDA protocol. METHODS: Twelve eyes of 12 patients with myopia between -1.75 and -5.00 diopters underwent 193 nm argon/fluoride excimer laser photorefractive keratectomy. The epithelium was mechanically removed, and fixation was accomplished with a suction ring which provided nitrogen flow across the corneal surface. The computer controlled corneal ablations were 5.00 mm in diameter and were accomplished with an iris diaphragm closing from large to small. RESULTS: The preoperative spherical equivalent myopia was -3.50 D (SD = 1.02) and the postoperative myopia was -0.25 (SD = 0.48). Eleven of the 12 patients achieved an uncorrected visual acuity of 20/30 or better and were corrected to within +/- 0.50 D of emmetropia. All corneas demonstrated a mild reticular subepithelial haze which was barely visible at 1 year. There were no vision-threatening complications and none of the eyes experienced a loss of best corrected visual acuity. CONCLUSIONS: In this small trial, the excimer laser appears to be capable of accurately changing the refractive power of the cornea for the correction of myopia with minimal side effects. Only when larger numbers of patients undergo the procedure will we be able to determine the safety and efficacy of photorefractive keratectomy as a refractive surgical procedure.

Adult↗
PubMedDate not supplied

A comparison of excimer laser (308 nm) ablation of the human lens nucleus in air and saline with a fiber optic delivery system.

BACKGROUND: Photoablation with excimer lasers has demonstrated precise tissue cutting and minimal thermal damage. Potential ophthalmic applications of these lasers include remodelling of the corneal surface, glaucoma treatment, and phacoablation. Ablation of human lens with a 308 nm XeCl excimer laser light delivered through a fiber has been demonstrated in preliminary experiments. Intraocular delivery of laser light must be done in a fluid medium to preserve the integrity of ocular structures. However, little information is available on the effect of the fluid media on the ablation process. Therefore, a series of experiments was conducted to determine whether the ablation of human lens nucleus at 308 nm via a fiber differs in air and saline media. METHODS: Ablation of human lens nuclei (n = 30) was conducted with a XeCI excimer laser (308 nm) coupled to a 600 microns core size fiber. Irradiation was performed at 2.8 mJ/cm2 energy density and 20 Hz. The fiberoptic was brought to contact with the lens nucleus and remained fixed for the duration of irradiation. Variables consisted of the medium (air or saline) and number of pulses delivered (100 to 10,000). Following establishment of the tissue shrinkage ratio, the depth of each crater and the tissue volume removed were measured histologically. The histological features of nucleus ablation in air and in saline were also examined with both light and scanning electron microscopy. RESULTS: Light microscopy revealed that the average zone of thermal damage adjacent to the crater is thinner in the presence of saline (60 microns, SD = 6 microns) than it is in air (90 microns, SD = 12 microns). In both media, the thickness of the zone of thermal damage is greater at the surface than it is at its base. Following irradiation in air, deep sharpedged craters with smooth walls are formed. Craters formed by irradiation in saline are characterized by reduced depth and irregular walls. For the same number of pulses applied (500, 1000, and 2000), the mean depth of ablation per pulse in air (8.6 to 2.7 microns/pulse) was greater by approximately a factor of two than that in saline (4.10 to 1.30 microns/pulse) at P < .01. However, the mean ablated volume removed per pulse was greater in saline (0.00250 to 0.00150 mm3/pulse) than in air (0.00120 to 0.00080 mm3/pulse), for the same number of pulses (1000, 2000) at P < .01. CONCLUSIONS: In comparing the data for the same number of pulses applied in air and in saline, it appears that the depth of crater formed by irradiation in air is deeper than that in fluid. The overall volume ablated is greater in fluid than it is in air at 1000 and 2000 pulses. Additionally, the zone of thermal damage is thinner in the presence of saline than it is in air. Smoother crater shapes were observed following irradiation in air than in saline. These results suggest that under this specific experimental setup, the ablation in saline is different from that in air.

Aged↗
PubMedDate not supplied

Effect of nitrogen flow on recovery of vision after excimer laser photorefractive keratectomy without nitrogen flow.

BACKGROUND: Excimer laser (VISX) photorefractive keratectomy was performed using nitrogen flowing through the ocular fixation ring. It was felt that eliminating nitrogen flow may provide faster early visual rehabilitation. METHODS: Two groups of 50 consecutive eyes underwent photorefractive keratectomy with (N2 flow) and without (no N2 flow) nitrogen flow, and were evaluated at 1 month postoperatively. RESULTS: There were more under- or overcorrections exceeding 1.00 diopter (D) in the N2 flow than in the no N2 flow groups. Eighteen eyes in the N2 flow and 11 in no N2 flow groups saw 20/50 or less, without correction. Fourteen eyes in the N2 flow and nine eyes in the no N2 flow groups lost two or more lines of best spectacle-corrected visual acuity. Four eyes in the N2 flow and none in the no N2 flow groups increased more than 1.00 D of astigmatism. CONCLUSION: The elimination of nitrogen flow in photorefractive keratectomy performed with the VISX laser appears to improve visual results in the early postoperative period.

Adult↗
PubMedDate not supplied

Prognostic variables in greek patients with stage II breast cancer: a Hellenic Cooperative Oncology Group study.

The independent effects of several patient, tumor and treatment-related prognostic factors on relapse-free survival (RFS) and overall survival (OS) were assessed by Cox multivariate regression analysis in 988 Greek patients with stage II breast cancer. At a median follow-up time of 83 (range 3.3-131+) months and after the evaluation of all patients together, the number of positive axillary nodes (p < 0.0001), tumor size (p = 0.0024) and tumor grade (p = 0.0008) were identified as significant prognostic factors for RFS. Also, the number of positive nodes (p < 0.0001), tumor size (p = 0.0002) and ER status (p = 0.0001) were found to be significant for OS. These short-term prognostic variables are similar to those reported for this group of patients in other European countries and in the USA.

Adult↗