Biomedical subjects

A Queirós

Publications and source records attributed to A Queirós.

5 recordsLinked to original sources

PubMed2006

Age differences in central and peripheral intraocular pressure using a rebound tonometer.

AIM: To evaluate the influence of age on the measurements and relationships among central and peripheral intraocular pressure (IOP) readings taken with a rebound tonometer. METHODS: The IOPs were measured using the ICare rebound tonometer on the right eyes of 217 patients (88 men and 129 women) aged 18-85 years (mean 45.9 (SD 19.8) years), at the centre and at 2 mm from the nasal and temporal limbus along the horizontal meridian. Three age groups were established: young (< or =30 years old; n = 75), middle aged (31-60 years old; n = 77) and old patients (>60 years old; n = 65). RESULTS: A high correlation was found between the central and peripheral IOP readings, with the central readings being higher than the peripheral ones. Higher IOP values for the central location were found in the younger patients. Older patients had significantly lower temporal IOP readings than those for the remaining two groups (p<0.001), whereas no significant differences were found among groups when IOP was measured at the central and nasal locations. A significant decrease was observed in the nasal and temporal IOP readings as the age increased (p = 0.011 and 0.006, respectively). CONCLUSION: Older patients had lower IOP values than the middle-aged and younger patients in the temporal peripheral location. A negative correlation was found between age and IOP by rebound tonometry in the corneal periphery but not in its centre.

Adolescent↗

PubMed2006

Non-contact tonometry synchronized with cardiac rhythm and its relationship with blood pressure.

PURPOSE: The main objectives of this study were to determine the differences between non-synchronized intraocular pressure (IOP_N) and intraocular pressure readings synchronized with cardiac pulse and try to determine if these parameters are related to blood pressure values. METHODS: One hundred and sixty-five right eyes from 165 volunteers (107 females, 58 males) aged from 19 to 73 years (mean +/- S.D., 29.93 +/- 11.17) were examined with the Nidek NT-4000, a new non-contact tonometer that allows the measurement of IOP synchronized with the cardiac rhythm. IOP measurements in the four different modes of synchronization were taken in a randomized order. Three measures of each parameter were taken and then averaged. The blood pressure was determined three times with a portable manometer and mean values of systolic and diastolic pressure and the pulse rate were computed. Mean arterial pressure (MAP) was determined as being 1/3 of systolic plus 2/3 of diastolic blood pressure. RESULTS: The mean +/- S.D. values for the standard intraocular pressure (IOP_N: 14.76 +/- 2.86), intraocular pressure in the systolic instant or peak (IOP_P: 14.99 +/- 2.85), intraocular pressure in the middle instant between heartbeats or middle (IOP_M: 14.68 +/- 2.76), and intraocular pressure in the diastolic instant or bottom (IOP_B: 13.86 +/- 2.61) were obtained. The IOP_P was higher than the remaining values. A significant difference in mean IOP existed between IOP_B and the remaining modes of measuring (p < 0.05). Differences were statistically significant for all pair comparisons involving IOP_B. Arterial blood pressure values were systolic 125.5 +/- 14.22, diastolic 77.7 +/- 8.38 and MAP 93.64 +/- 9.44 mmHg. The pulse rate was 77.3 +/- 12.6 beats per minute. Except for the MAP (p = 0.025) there was no significant correlation between different IOP values and systolic or diastolic blood pressure, or pulse rate. CONCLUSIONS: NT-4000 is able to differentiate IOP values when synchronized with the cardiac rhythm and those differences are expected to be within a range of +/-2.5 to +/- 3.0 mmHg. IOP_B seems to be the parameter whose value differs from the non-synchronized and the remaining synchronized parameters in a significant way. Other than a weak association with MAP, no significant correlation between IOP and BP was found. The measurements of IOP readings for the three modes are consistent with timings during the cardiac cycle and IOP pulse cycle.

Adult↗

PubMed2005

Comparison of the ICare rebound tonometer with the Goldmann tonometer in a normal population.

The aim of this study was to evaluate the accuracy of measurement of intraocular pressure (IOP) using a new induction/impact rebound tonometer (ICare) in comparison with the Goldmann applanation tonometer (AT). The left eyes of 46 university students were assessed with the two tonometers, with induction tonometry being performed first. The ICare was handled by an optometrist and the Goldmann tonometer by an ophthalmologist. In this study, statistically significant differences were found when comparing the ICare rebound tonometer with applanation tonometry (AT) (p < 0.05). The mean difference between the two tonometers was 1.34 +/- 2.03 mmHg (mean +/- S.D.) and the 95% limits of agreement were +/-3.98 mmHg. A frequency distribution of the differences demonstrated that in more than 80% of cases the IOP readings differed by <3 mmHg between the ICare and the AT. In the present population the ICare overestimates the IOP value by 1.34 mmHg on average when compared with Goldmann tonometer. Nevertheless, the ICare tonometer may be helpful as a screening tool when Goldmann applanation tonometry is not applicable or not recommended, as it is able to estimate IOP within a range of +/-3.00 mmHg in more than 80% of the population.

Adolescent↗

PubMed1998

Hepatitis C virus genotypes and the influence of the induction of immunosuppression with anti-thymocyte globulin (ATG) on chronic hepatitis in renal graft recipients.

Hepatitis C virus (HCV) exhibits a dramatic genetic variability and several mechanisms of immunological response are unable to control hepatic and extrahepatic replication. Genotype 1 b is associated with more severe clinical manifestations and is less responsive to interferon. In addition, we have reported an increase of HCV RNA viral load after renal transplantation. Anti-thymocyte globulin (ATG) is supposed to increase viral replication and liver dysfunction in chronically infected renal graft recipients. We evaluated the genotype profile in HCV+ patients of our Renal Transplant Unit and studied the effects of ATG, as part of the induction of immunosuppression, on viral load and liver enzymes abnormalities. From 726 renal graft recipients, 104 patients, with a mean follow up of 3.9 +/- 2.9 years, were anti-HCV+ by ELISA II. HCV RNA was measured by quantitative PCR. We correlated the viral load and biochemical liver parameters with genotype, exposure to ATG as induction therapy, early acute rejection episode and the duration of infection. Of the 81 patients tested, 72% were viraemic and genotype 1 b was the predominant viral strain (66%). The majority of these patients (65%) were coinfected by two or more strains. There was no correlation between HCV RNA blood levels and liver enzymes. We did not find higher viral load with genotype 1 b infection (68 +/- 88 mEq/ml vs 75.8 +/- 123 mEq/ml in the others) nor with ATG induction therapy (43.5 +/- 71.3 mEq/ml vs 64.1 +/- 110.5 mEq/ml). Early acute rejection and longer follow up were not associated with higher levels of HCV RNA. The biochemical liver profile showed no relationship with the variables studied. We concluded that genotype 1 b is the predominant strain in our HCV+ population and there is a great prevalence of coinfection with several genotypes. Our results did not confirm a deleterious effect of the use of ATG as induction therapy in these HCV-infected patients. Prospective randomised studies with liver biopsy evaluation are needed to answer more fully the remaining questions about the best immunosuppressive therapy in renal graft recipients with chronic HCV infection.

Genotype↗

PubMed1982

Traumatic diaphragmatic hernias: a report of 19 cases.

From an analysis of 19 patients with traumatic diaphragmatic hernias with respect to the type of injury, associated injuries, clinical and radiologic features, diagnosis, surgical management and causes of death and from a review of the literature, the authors draw a number of conclusions. 1. Careful clinical examination coupled with an accurate interpretation of the roentgenograms should detect most cases of traumatic rupture of the diaphragm. 2. Impairment of respiratory function, possibility of strangulation and incarceration of the abdominal viscera demand early repair. 3. The choice of incision and approach depends on the stage at which the rupture is recognized (early or late), the site of rupture and the associated injuries. 4. Careful assessment of respiratory function should be made in order to prevent postoperative complications; in some cases respiration must be assisted. 5. Although the mortality in patients with traumatic diaphragmatic rupture is still relatively high, the deaths sould not be related to the rupture per se, or to its repair, but rather to the associated injuries.

Adolescent↗