Alternativas de tratamiento de la obstrucción venosa retiniana: terapias combinadas y vitrectomía pars plana

Dentro de las enfermedades vasculares de la retina, la oclusión venosa retiniana es relativamente frecuente y debido a sus complicaciones afecta de forma moderada o grave la visión. Las opciones terapéuticas aplicadas en el edema macular y los desprendimientos de retina traccionales causados por las oclusiones venosas son varias. Se realizó una revisión en la literatura científica para valorar la eficacia y seguridad del uso combinado de diferentes terapias que incluye los antiangiogénicos y esteroides intravítreos con o sin aplicación de láser, así como la vitrectomía pars plana como alternativas de tratamiento de las complicaciones de la enfermedad oclusiva venosa retiniana. Aun cuando los antiangiogénicos se consideren como primera línea de tratamiento en la oclusión venosa retiniana, en varios casos hay mejor respuesta en sus combinaciones y de los esteroides con láser. Para resolver el desprendimiento de retina traccional y hemorragia vítrea, debidas a las oclusiones venosas, se requiere, mayormente, operación de vitrectomía pars plana. Se realizó una búsqueda en bases de datos electrónicas como PubMed, Cochrane y otras publicaciones relacionadas con las alternativas de tratamiento de la obstrucción venosa retiniana en los últimos años.

Among retinal vascular diseases, retinal venous occlusion is relatively frequent and due to its complications, it moderately or severely affects vision. The therapeutic options applied in macular edema and tractional retinal detachments caused by venous occlusions are several. A review of the scientific literature was performed to assess the efficacy and safety of the combined use of different therapies including intravitreal antiangiogenics and steroids with or without laser application, as well as pars plana vitrectomy as treatment alternatives for the complications of retinal venous occlusive disease. Even when antiangiogenics are considered as first line of treatment in retinal venous occlusion, in several cases there is better response in their combinations and steroids with laser. To resolve tractional retinal detachment and vitreous hemorrhage due to venous occlusions, a pars plana vitrectomy operation is mostly required. A search was made in electronic databases such as PubMed, Cochrane and other publications related to treatment alternatives for retinal venous obstruction in recent years.

The Efficacy And Validity Of Blood Flow Restriction Training In Clinical And Post-Surgical Populations

Background: We currently know BFR training is a viable modality for strength gains in the healthy population. However, it is unknown the effect of BFR training on post-surgical and clinical populations. Furthermore, the optimal use of the BFR modality regarding resistance vs. no-resistance (bodyweight) is also unknown. This literature review adds new information to the field of BFR training specifically in the post-surgical and clinical populations. The objective of the study is to explore the validity and efficacy of blood-restriction training (BFR) in conjunction with low-load resistance training (LL-BFR) versus low-load training without BFR and high-load resistance training without BFR to determine which is superior for strength gains. Methods: The authors used SPORTDiscus, EBSCO, PubMed, and Science Direct to search for peer-reviewed articles. The articles chosen had the keywords/phrases “BFR,” “vascular occlusion,” “strength training,” “resistance training.” The studied emphasized patients with either clinical conditions (osteoarthritis) or musculoskeletal injuries (ACL reconstruction, total knee arthroplasty, knee arthroscopy). One hundred seventy-one articles were screened, and 17 articles reviewed. Results: BFR, in conjunction with low-load resistance training yields superior strength gains when compared to lowload training alone (p<.05). The outcome measures show a higher 1-rep max (isotonic strength) and greater muscle size (cross-sectional area, muscle mass, muscle volume) (p<.05). However, BFR with low-load resistance training does not yield superior strength gains in comparison to high-load resistance training alone (p<.03). Conclusion: As healthcare providers treating patients with musculoskeletal conditions, we know the importance of resistance training as a tool for rehabilitation and activities of daily living. However, at times heavy resistance training is contraindicated either due to joint instability/degeneration, pain, surgical restrictions. BFR training can be implemented with a 10-30% 1-rep max for comparable strength gains. This can be a potential tool used to offset post-surgical atrophy and atrophy due to arthralgia seen in certain systemic conditions. This can translate to better functional outcomes in post-surgical patients and superior quality of life in the geriatric population.

Bevacizumab versus ziv-aflibercept in branch retinal vein occlusion

Purpose: To compare the effectiveness of treatment with intravitreal bevacizumab (IVB) and ziv-aflibercept (IVZ) in patients with macular edema (ME) post-branch retinal vein occlusion (BRVO). Methods: Patients with treatment naïve ME post-BRVO were included retrospectively if they received either IVB (0.05 ml/1.25 mg) or IVZ (0.05 ml/1.25 mg) monotherapy with a follow up of 12 months. Results: Thirty-two and 17 eyes received IVB and IVZ, respectively. The mean improvement in best corrected visual acuity (BCVA) was 0.36 ± 0.3 logarithm of minimum angle of resolution (logMAR) in the IVB group and 0.27 ± 0.3 in the IVZ group (P = 0.35). The mean change in central macular thickness was 178.9 ± 180.9 and 173.5 ± 344.4 ?m in IVB and IVZ groups, respectively (P = 0.94). The mean number of injections was higher in the IVB group (4.0 ± 1.8) compared with 1.82 ± 0.8 in the IVZ group (P < 0.0001). The IVZ group had significantly fewer number of visits (P < 0.0001) and longer maximum treatment-free intervals (P = 0.0081). Conclusion: IVZ appears to be cost-effective with the similar visual outcome and less number of visits in comparison to IVB.

The Usefulness of Transcutaneous Tissue Oxygen Pressure (TcpO2) for Determination of the Point of Time at Venous Revascularization

PURPOSE: The purpose of this study is to delineate the optimal time of venous revascularization for preventing the flap necrosis due to venous occlusion, and to clarify the usefulness of tissue oxygen pressure (TcpO2) in the determination of the point of time for venous revascularization. METHODS: Thirty-six, 3 x 3 cm sized epigastric island flap was elevated in left abdomen of male Sprague-Dawley rat weighing 250 gram. Flaps were randomly assigned to six groups of six flaps according to the duration of venous occlusion with microvascular clamp; 10 minutes in the group I as the control, 60 minutes in the group II, 2 hours in the group III, 3 hours in the group IV, 4 hours in the group V, and 6 hours in the group VI, respectively. Just before removal of clamp after flap was reposed in situ, the ratio of TcpO2 (tissue oxygen pressure) of the island flap to that of right abdomen was calculated in each group, and tissue specimen was harvested from the distal area of the flap for histological evaluation of vascular change. Five days later, survival area of the flap was estimated, and evaluated the correlation between the tissue oxygen pressure and the rate of flap survival. RESULTS: The TcpO2 and the survival rate of flap were decreased proportionally with the duration of venous occlusion. The ratio of the TcpO2 of the flap is decreased abruptly to below sixty percentile compared to the TcpO2 of normal tissue, and the survived area of the flap is decreased to nine-tenth of the designed size after three hours of total venous occlusion. Histologically, the number of congested vessels was increased according to venous occluded time, and proportionally increased after 3-hours of occlusion significantly. CONCLUSION: There is a close correlation between the TcpO2 and the survival rate of flaps according to the duration of venous occlusion. Therefore, the TcpO2 represents the hemodynamic changes within the flap, and thought to be an alternative effective tool in the flap monitoring for venous revascularization.

Macrovascular dysfunction detected by comparison of serum FDP detected by simplified venous occlusion test in patients with NIDDM and CVA / 대한내과학회지

OBJECTIVES: In diabetic patients, the incidence of atherosclerotic disease are increased, which may be due to decreased fibrinolytic activity. The aim of study is to elucidate the relationship between angiopathies and vascular function evaluated by simplified venous occlusion test in patients with non-insulin dependent diabetes mellitus (NIDDM) and cerebrovascular accident (CVA). METHODS: The study was conducted on 63 patients who were hospitalized during the period from March 1, 1994 to May 30, 1997. The serum concentration of fibrinogen degradation products (FDP) was measured before and 5 min after venous occlusion in 31 NIDDM patients, 16 CVA patients and 16 age-matched control subjects. FDP was measured with the anti-fibrinogen- coated latex particle agglutinin assay system. RESULTS: 1) The basal serum FDP level was higher in diabetic patients with macroangiopathy (12.3+/-5.8 ug/ml) and patients with CVA (11.2+/-5.1 ug/ml) than in control subjects (5.7+/-1.8 ug/ml) (p<0.05). 2) The increment of serum FDP level after venous occlusion in diabetic patients with microangiopathy (6.6+/-2.2 to 10.3+/-4.1 ug/ml) and control subjects (5.7+/-1.8 to 11.4+/-4.3 ug/ml) was significantly higher than basal serum FDP level (p<0.05). But the increment of serum FDP level after venous occlusion in diabetic patients with macroangiopathy (12.3+/-5.8 to 15.2+/-5.1 ug/ml) and patients with CVA (11.2+/-5.1 to 13.7+/-4.8 ug/ml) wasn't significantly higher than basal serum FDP level. 3) The increment rate of serum FDP after venous occlusion in diabetic patients with macroangiopathy (24.4+/-29.3%) and patients with CVA (29.4+/-34.5%) was significantly lower than diabetic patients with microangiopathy (66.3+/-71.7%) and control subjects (84.1+/-69.3%) (p<0.05). CONCLUSION: The responsiveness of fibrinolytic activity to venous occlusion was significantly lower in diabetic patients with macroangiopathy, as in patients with CVA, compared with that in control subjects. We conclude that measurement of the increase in serum FDP concentration 5 min after venous occlusion may be useful to detect vascular dysfunction in patients with macrovascular disease caused by atherosclerosis.

Establishment of acute cerebral venous occlusion and evaluation of it with magnetic resonance imaging / 重庆医科大学学报

Objective:To establish a stable animal model of acute cerebral venous occlusion and to evaluate the model with DWI,PWI,MRS and DTI in observing the changing regularity of the brain parenchymal lesions.Methods:Thirty cats were randomly divided into 2 groups,operation group(n=24) and sham operation group(n=6).Operation group was performed by injection of the cellulose acetate polymer(CAP) solution into the superior sagittal sinus(SSS) to establish the acute cerebral venous occlusion,while sham operation group underwent only the exposure of SSS.MRI was performed at 1,3,6,12,24 and 48h after operation.Results:Twenty-two cats in operation group were operated successfully.Twenty-five lesions were detected on DWI in 14 cats.Thirty-one abnormal perfusion regions were detected on PWI in 17 cats.MRS showed that Lac increased obviously in 1h after operation and decreased gradually later,and NAA decreased in 3h.DTI showed that ADCav values decreased in 1h,increased 3h later and FA values decreased at all time points after operation.The microscopic changes were mainly vasogenic edema and followed by venous cerebral infarction and cerebral hemorrhage in 12h.No abnormal findings were observed in sham operation group.Conclusion:Establishment of acute cerebral venous occlusion model by injection of CAP solution into SSS is feasible.The model is suitable for pathophysiological and radiological studies.DWI combined PWI,MRS and DTI have great value in judging the dynamic changes and the etiopathogenesis of brain parenchymal lesions in acute cerebral venous occlusion.