Evaluation of ocular pulse amplitude changes after the retinal detachment repair

Purpose: The study was conducted to determine the ocular pulse amplitude (OPA) changes, measured with a dynamic contour tonometer (DCT), after surgical retinal detachment repair. Methods: This was a prospective and comparative study. Thirty patients (30 eyes) who had undergone uncomplicated unilateral scleral buckling and encircling procedures for quadrant or half?retinal rhegmatogenous retinal detachment were referred for DCT one day before the surgery was performed, on the 1st, 7th, and 30th postoperative day. Methods of descriptive (arithmetical mean, standard deviation) and analytical statistics (analysis of variance) were used to analyze the data and evaluate the significance of the difference. A value of P less than 0.05 was considered statistically significant. The data were evaluated for normality with the single?sample Kolmogorov–Smirnov test. Results: OPA values decreased significantly after scleral buckling procedures (p < 0.0001), but regained near to preoperative values one month after the surgery. Conclusion: OPA tends to decrease after retinal detachment surgery. Restoring patients’ vision with scleral buckling and encircling procedures gives early changes in blood supply to the choroid and ocular nerve, and since OPA is an indirect parameter of choroidal vascularization, measuring these values can help make an insight into ocular hemodynamics.

Rebound Tonometers versus Other Tonometers: Agreement among Readings and the Effects of Axial Length, Ocular Pulse Amplitude, and Central Corneal Thickness on Readings

OBJECTIVE: The aim of this study was to use intraocular pressure (IOP) measurements obtained via rebound tonometry (RBT, the I-care instrument), Goldmann applanation tonometry (GAT), non-contact tonometry (NCT), dynamic contour tonometry (DCT, PASCAL), and the TonoPen to investigate the consistency of readings among methods and the influence of ocular pulse amplitude (OPA), axial length (AL), and central corneal thickness (CCT) on RBT data. METHODS: We prospectively studied 123 eyes. IOP was measured via RBT, GAT, NCT, DCT, and the TonoPen. In addition, OPA was measured via DCT, AL, and CCT. Correlations among measurements using the various methods were evaluated, as were the effects of OPA, AL, and CCT on RBT data. RESULTS: RBT data were significantly correlated with data obtained via GAT, NCT, DCT, and the TonoPen; the highest correlation was with GAT. OPA was significantly correlated with IOP measured via GAT but not with IOP measured via RBT. Both AL and CCT were significantly correlated with IOP data obtained via RBT and GAT. CONCLUSION: Significant correlations were evident among IOP measurements obtained via RBT and other tonometry methods. However, the influence of AL and CCT on IOP measurements obtained via RBT requires careful consideration and interpretation. Although the IOP values obtained by GAT were correlated with OPA values obtained by DCT, this was not true of IOP data obtained by RBT. This might be associated with characteristic of RBT which has the relatively short corneal contact time.

The Effect of Corneal Biomechanical Factors on Ocular Pulse Amplitude in Normal Subjects

PURPOSE: To investigate the influence of corneal biomechanical factors on ocular pulse amplitude measured using dynamic contour tonometry in normal subjects. METHODS: The study population consisted of normal subjects who visited the outpatient clinic from January, 2014 to July, 2014. Ocular pulse amplitude was measured using dynamic contour tonometry and corneal hysteresis (CH) and corneal resistance factor (CRF) were measured using an ocular response analyzer. We applied univariate and multivariate linear regressions to investigate the relationship between ocular pulse amplitude and corneal biomechanical factors and other ocular factors. RESULTS: Fifty eyes of 50 patients (average age 52.8 +/- 17.2 years) were examined. The average ocular pulse amplitude was 2.90 +/- 1.04 mm Hg and the CH and CRF were 10.44 +/- 1.96 mm Hg and 11.03 +/- 2.21 mm Hg, respectively. In univariate linear regression, factors influencing ocular pulse amplitude were ocular pressure based on CRF (beta = 0.280, p = 0.049), Goldmann applanation tonometry (beta = 0.293, p = 0.039), and spherical equivalent (beta = 0.283, p = 0.047), while in multivariate linear regression the only factor influencing ocular pulse amplitude was CRF (beta = 0.686, p = 0.042). CONCLUSIONS: A positive correlation between ocular pulse amplitude reflecting ocular perfusion pressure and CRF reflecting corneal elasticity was observed. Correlations between the 2 factors will be an important aspect in future studies regarding the influences of corneal biomechanical factors on ocular perfusion pressure in glaucoma patients.

Positional Change of Intraocular Pressure and Its Relationship to Ocular Pulse Amplitude

PURPOSE: To investigate the postural change of intraocular pressure (IOP) from sitting to supine position and determine the relationship to other ocular parameters including ocular pulse amplitude (OPA) in glaucoma suspect and open angle glaucoma patients. METHODS: The present study included 46 eyes of 46 patients. First, we measured IOP and OPA using Goldmann applanation tonometer (GAT), Pascal dynamic contour tonometer and TonoPen(R). Using TonoPen(R), the IOP was measured immediately after the subjects were placed in a supine position and 10 minutes and 30 minutes thereafter. We also investigated the correlation between positional change of IOP and axial length (AL), refractive error (RE), and OPA. RESULTS: IOPs of patients in a sitting position measured with GAT and TonoPen(R) were 15.3 +/- 3.3 mm Hg and 16.6 +/- 2.9 mm Hg, respectively, and OPA was 2.57 +/- 0.89 mm Hg. IOPs measured with TonoPen(R) were 17.6 +/- 2.9 mm Hg immediately after position change, 18.2 +/- 3.7 mm Hg after 10 minutes and 17.5 +/- 2.7 mm Hg after 30 minutes. Each IOP change was statistically significant and the largest change was after 10 minutes. Changes of IOP after 10 minutes were positively correlated with OPA (R = 0.340) and RE (R = 0.330) and negatively correlated with AL (R = -0.410). CONCLUSIONS: When placed in a supine position, the IOP of patients increased and then decreased over time. Positional IOP change was influenced by AL and OPA and variable hemodynamic factors and apparently influenced OPA and ocular perfusion pressure.

Comparison of Ocular Pulse Amplitude Measured Using Dynamic Contour Tonometry and Ocular Blood Flow Analyzer

PURPOSE: To compare ocular pulse amplitude (OPA) measured using dynamic contour tonometry (DCT) and ocular blood flow analyzer (BFA). METHODS: Thirty-five eyes of 35 patients were enrolled in this cross-sectional and retrospective study. OPA was measured using DCT. Pulse amplitude (PA) and pulsatile ocular blood flow were measured using BFA. RESULTS: OPA measured using DCT (2.79 +/- 0.89 mm Hg) was not significantly different from PA measured with BFA (3.02 +/- 0.90 mm Hg; p = 0.082) and both were significantly correlated (r = 0.663, p < 0.001). Mean difference +/- limit of agreement was -0.22 +/- 1.44 mm Hg between OPA and PA. OPA correlated significantly with intraocular pressure (IOP) measured using Goldmann applanation tonometry (r = 0.330, p = 0.047) but not PA (r = 0.057, p = 0.745). Both PA and OPA did not show significant correlation with the spherical equivalent of refractive error and central corneal thickness. CONCLUSIONS: Although both OPA and PA measure IOP fluctuation and are not significantly different, they showed different relationships with IOP.

Comparison of Dorzolamide-Timolol Fixed Combination and Latanoprost, Effects on Intraocular Pressure and Ocular Pulse Amplitude

PURPOSE: To compare dorzolamide-timolol fixed combination (DTFC) and latanoprost with regard to their effects on intraocular pressure (IOP) and ocular pulse amplitude (OPA). METHODS: Sixty eyes of 60 patients with open angle glaucoma or glaucoma suspect were included in the present study. Patients were divided into 2 groups, DTFC-treated (n = 30) and latanoprost-treated (n = 30). IOP and OPA were measured with dynamic contour tonometer (DCT) and Goldmann applanation tonometer (GAT), before and at least 1 month after treatment. RESULTS: GAT IOP, DCT IOP and OPA decreased by 2.25 +/- 2.23 mm Hg, 1.97 +/- 2.06 mm Hg, and 0.14 +/- 0.88 mm Hg, respectively in the DTFC-treated group. In the latanoprost-treated group, GAT IOP, DCT IOP and OPA was reduced by 2.74 +/- 2.96 mm Hg, 2.06 +/- 3.50 mm Hg, and 0.69 +/- 1.07 mm Hg, respectively. There was no significant difference (p = 0.311) in the decline of IOP between the 2 groups, but OPA of the DTFC-treated group decreased less than the latanoprost-treated group (p = 0.032). CONCLUSIONS: No significant differences were observed in the short-term decline of IOP between the 2 medications. However, the influence of DTFC on OPA appeared negligible in the latanoprost-treated group.

Analysis of Clinical Effectiveness of Tafluprost by Ocular Pulse Amplitude

PURPOSE: To analyze the clinical effectiveness of tafluprost used in the treatment of glaucoma, using ocular pulse amplitude (OPA) measurements with dynamic contour tonometry (DCT). METHODS: Sixty patients (119 eyes) with normal tension glaucoma (NTG) or primary open angle glaucoma (POAG) treated with tafluprost or other eyedrops were investigated in the present study. Intraocular pressure (IOP) was measured with Goldmann applanation tonometry (GAT), and OPA was measured with DCT, before and after treatment, retrospectively. RESULTS: In 20 patients treated with tafluprost, IOP decreased from 17.1 mm Hg before treatment to 13.0 mm Hg 3 months after treatment (24.0% descent rate), and OPA decreased from 2.35 to 1.57 (33.2% descent rate). For 20 patients who switched from another monotherapy to tafluprost, IOP decreased from 15.7 mm Hg to 13.2 mm Hg from 15.7 mm Hg (15.3%) and OPA from 2.38 to 1.69 (27.7%). CONCLUSIONS: Tafluprost used to treat glaucoma has a large OPA and IOP lowering effect and, therefore can be applied to patients who have a large OPA with glaucoma progression in spite of well controlled IOP.

The Effect of Cataract Surgery on Ocular Pulse Amplitude

PURPOSE: To investigate the change of intraocular pressure (IOP) and ocular pulse amplitude (OPA) measured by dynamic contour tonometry (DCT) after cataract surgery and to identify the influencing factors related with OPA change after cataract extraction. METHODS: The present study included 32 patients who underwent unilateral cataract surgery and the non-operated fellow eyes were used as control. IOP was measured by Goldman applanation tonometry (GAT) and Pascal DCT preoperatively, and 3 months postoperatively. Additionally, OPA was measured by Pascal DCT preoperatively, and 3 months postoperatively. Axial length (AL), anterior chamber depth (ACD), and central corneal thickness (CCT) were measured preoperatively. RESULTS: After cataract surgery, IOP by GAT, IOP by DCT, and OPA decreased significantly with a mean decrement of 1.3 mm Hg, 1.6 mm Hg, and 0.5 mm Hg, respectively (p 0.05) postoperatively. The most important factor influencing the decrement of IOP by GAT, IOP by DCT, and OPA after cataract surgery was the preoperative level of their measurements (r = 0.382, p < 0.05 in GAT, r = 0.807, p < 0.001 in DCT, r = 0.627, p < 0.001 in OPA). In addition, the OPA decrement after cataract surgery was significantly correlated with age (r = -0.370, p = 0.037), and was not correlated with AL, ACD, and CCT. CONCLUSIONS: Both IOP and OPA decreased after cataract surgery, which appears to influence the relationship between IOP and OPA. The correlation between OPA decrement and age may be related to increased ocular rigidity with aging.

The Effect of Cataract Surgery on Ocular Pulse Amplitude

PURPOSE: To investigate the change of intraocular pressure (IOP) and ocular pulse amplitude (OPA) measured by dynamic contour tonometry (DCT) after cataract surgery and to identify the influencing factors related with OPA change after cataract extraction. METHODS: The present study included 32 patients who underwent unilateral cataract surgery and the non-operated fellow eyes were used as control. IOP was measured by Goldman applanation tonometry (GAT) and Pascal DCT preoperatively, and 3 months postoperatively. Additionally, OPA was measured by Pascal DCT preoperatively, and 3 months postoperatively. Axial length (AL), anterior chamber depth (ACD), and central corneal thickness (CCT) were measured preoperatively. RESULTS: After cataract surgery, IOP by GAT, IOP by DCT, and OPA decreased significantly with a mean decrement of 1.3 mm Hg, 1.6 mm Hg, and 0.5 mm Hg, respectively (p 0.05) postoperatively. The most important factor influencing the decrement of IOP by GAT, IOP by DCT, and OPA after cataract surgery was the preoperative level of their measurements (r = 0.382, p < 0.05 in GAT, r = 0.807, p < 0.001 in DCT, r = 0.627, p < 0.001 in OPA). In addition, the OPA decrement after cataract surgery was significantly correlated with age (r = -0.370, p = 0.037), and was not correlated with AL, ACD, and CCT. CONCLUSIONS: Both IOP and OPA decreased after cataract surgery, which appears to influence the relationship between IOP and OPA. The correlation between OPA decrement and age may be related to increased ocular rigidity with aging.

Relación entre amplitud del pulso ocular y presión intraocular: efectividad del tratamiento hipotensor / Association of ocular pulse amplitude and intraocular pressure and effectiveness of the hypotensive treatment

OBJETIVOS: Determinar la asociación entre la amplitud del pulso ocular y la tensión ocular en los pacientes con glaucoma primario de ángulo abierto según grupos de tratamiento. Evaluar la amplitud del pulso ocular como medio para medir la efectividad de la terapia antihipertensiva ocular. Definir correlación entre espesor corneal central/tensión ocular y entre espesor corneal/amplitud del pulso usando el tonómetro de contorno dinámico. MÉTODOS: Se estudiaron 90 pacientes mayores de 15 años con diagnóstico reciente de glaucoma primario de ángulo abierto que aún no habían recibido tratamiento alguno; con ellos se conformaron tres grupos de estudio de forma aleatoria y según el medicamento indicado: Grupo l: Timolol 0,5 por ciento, Grupo II: Travoprost (Travatán) 0,2 por ciento y Grupo III: Dorzolamida (Trusopt) 2 por ciento. A estos pacientes se les tomó la medida del espesor corneal central por paquimetría previa al tratamiento, a la semana, al mes y a los 3 meses en el servicio de glaucoma del Hospital Ramón Pando Ferrer(diciembre-2006 a mayo-2007). Se midieron además las variables presión intraocular y amplitud del pulso ocular. RESULTADOS: Se encontró menor amplitud del pulso a medida que disminuía la presión intraocular, existió mayor descenso de la presión y de la amplitud del pulso en el grupo tratado con Travoprost, hubo para este grupo de tratamiento una mejor correlación entre ambas variables. No se encontró correlación entre el espesor corneal central y presión intraocular, ni entre espesor corneal y amplitud del pulso. CONCLUSIONES: Monitorear la presión y la amplitud del pulso puede ser eficaz para conocer el efecto de la terapéutica hipotensora ocular

OBJECTIVES: To determine the association of the ocular pulse amplitude and the ocular pressure in patients with primary open angle glaucoma by groups under treatment; to evaluate the ocular pulse amplitude as a means to assess the effectiveness of anti-hypertensive ocular therapy and to define correlation between central corneal thickness/ocular pressure, and corneal thickness and pulse amplitude using the dynamic contour tonometer. METHODS: Ninety patients aged over 15 years, recently diagnosed with primary open angle glaucoma and still untreated, were studied. They were randomly included in three study groups according to the indicated drug, that is, Group I- 0,5 percent Timolol, Group II- 0,2 percent Travoprost (Travatan) and Group III- 2 percent Dorzolamide (Trusopt). Their central corneal thickness was measured by pachymetry prior to the treatment, and one week, one month and 3 months later at the the glaucoma service at Ramón Pando Ferrer Cuban Institute of Ophthalmology (December 2006-May 2007). Also the variables intraocular pressure and ocular pulse amplitude were taken. RESULTS: It was found that pulse amplitude decreases as the intraocular pressure goes down; higher decline in pressure and pulse amplitude existed in group under Travoprost treatment where the correlation of both variables was better. No correlation was observed between central corneal thickness and intraocular pressure; similarly the corneal thickness and the pulse amplitude did not correlate. CONCLUSIONS: Monitoring the pressure and the pulse amplitude may be effective to find out the effect of the ocular hypertensive therapy

Effect of peribulbar anesthesia on intraocular pressure and ocular pulse amplitude / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the effect of peribulbar anesthesia on intraocular pressure(IOP)and ocular amplitude pulse(OPA).METHODS: Thirty-two consecutive adult patients with monocular cataract enrolled in this study. IOP and OPA were measured with dynamic contour tonometer(DCT)before and 3, 10 minutes after administration of lidocaine anesthesia. Data were analyzed with software SPSS 11.5.RESULTS: The IOP remained stable in the injected eyes and the non-injected eyes after administration of lidocaine anesthesia. The OPA was significantly decreased after injection of anesthesia agent in the injected eyes. The OPA in the non-injected eyes increased significantly 3 minutes after injection of the anesthesia agent, returning to preinjection level 10 minutes after the injection.CONCLUSION: Peribulbar anesthesia leads to decrease of OPA and shows no effect on IOP in the injected eyes.

Effect of Epinephrine or Pilocarpine on me Ocular Blood Flow

The ocular vascular resistance of the ciliary choroidal network has been investigated on measurements of pulse amplitude(PA). The ocular pulse is derived from the ciliary choroidal blood flow which account for more than 90% of the total ocular blood flow(OBF). In 5 normal Cynomolgus monkeys with topical application(50 micro l) of 2% epinephrine, the PA revealed a significant reduction(0.32 +/- 0.06mmHg, mean +/- SEM, p<0.01). In the other 5 normal Cynormlgus monkeys with 4% pilocarpine, the PA revealed no significant increment(0.32 +/- 0.15mmHg, mean +/- SEM, p<0.10) by the OBF system. These results suggest that topical application of epinephrine produces a significant reduction of OBR but pilocarpine produces a mild increment of OBF.

Effect of Epinephrine or Pilocarpine on me Ocular Blood Flow

The ocular vascular resistance of the ciliary choroidal network has been investigated on measurements of pulse amplitude(PA). The ocular pulse is derived from the ciliary choroidal blood flow which account for more than 90% of the total ocular blood flow(OBF). In 5 normal Cynomolgus monkeys with topical application(50 micro l) of 2% epinephrine, the PA revealed a significant reduction(0.32 +/- 0.06mmHg, mean +/- SEM, p<0.01). In the other 5 normal Cynormlgus monkeys with 4% pilocarpine, the PA revealed no significant increment(0.32 +/- 0.15mmHg, mean +/- SEM, p<0.10) by the OBF system. These results suggest that topical application of epinephrine produces a significant reduction of OBR but pilocarpine produces a mild increment of OBF.