Assessment of an tentative novel body of X-ray tube in order to decrease the applicability limitation in medical practice

The output of X-ray, especially in the field of required energy for diagnosing the disease is very low [in diagnosing lamps, it is less than 1%]. In this kind of lamps the rest of the electrical energy is transformed to heat. This considerable amount of heat induces a myriad of too many limitations in choosing higher levels of radiation, particularly in specialized techniques. This process is the outcome of X-ray generating mechanism; thus, one of the proper solutions to reduce the limitations caused by generating high heat is enhancing the cooling rate in these lamps. In this project, the design and alloy of the framework, surface and the substance were altered in a manner whereby the cooling rate increases or heat accumulation in lamps decreases. This surface was designed in the shape of a two-part disc with wings whose substance is the same as the framework. The substance of the framework is made of an alloy of copper and chromium. The disc shape of the framework and its aerodynamic compatibility further expose its contacting surface to the air. This contacting surface can be expanded to 10 times more than the ordinary frameworks. The heat conductivity coefficient of this alloy is approximately 220 w/ mk, which in comparison with the heat conductivity coefficient of the ordinary lamps framework, being about 10, is 22 times more. The results of the tests reveal that the cooling rate of this framework is 10 times [or 1000%] more than the ordinary one. This process reduces the limitations of choosing radiation factors with the same proportion

Effect of homatropine eye drops on pain after photorefractive keratectomy: a pilot study

To assess the effect of homatropine eye drops on pain after photorefractive keratectomy [PRK]. This randomized, double masked, interventional study included 15 patients [30 eyes] who underwent bilateral PRK. After operation, patients received homatropine eye drops, 4 times daily in only one eye [homatropine eye]. The level of pain was evaluated using visual analogue scale [VAS], verbal rating scale [VRS] and pain rating index [PRI] at 0.5, 24 and 48 h after operation. The level of pain was statistically similar between the two eyes half an hour after operation, however, homatropine eyes had significantly less pain 24 h after operation compared to fellow eyes [2.5 +/- 1.9 vs 5.3 +/- 2.5, P = 0.004 for VAS, 2.0 +/- 1.2 vs 3.2 +/- 0.9, P = 0.023 for VRS, and 9.4 +/- 5.7 vs 16.0 +/- 9.0, P = 0.031 for PRI]. Also, 48 h after surgery, the pain scales were less in the homatropine eyes [2.3 +/- 1.7 vs 4.0 +/- 2.1, P = 0.014 for VAS, 1.6 +/- 1.0 vs 2.5 +/- 1.0, P = 0.038 for VRS, and 6.8 +/- 5.7 vs 12.0 +/- 8.9, P = 0.005 for PRI]. No delayed epithelial healing was observed. Homatropine eye drops may be useful for reducing pain after Photorefractive keratectomy

Vitrectomy for posterior segment intraocular foreign bodies, visual and anatomical outcomes

To evaluate the visual and anatomic results and determine the prognostic factors after pars plana vitrectomy and posterior segment intraocular foreign body [IOFB] removal. This retrospective study reviews the patients' charts of 48 consecutive patients with posterior segment IOFB who underwent pars plana vitrectomy and IOFB removal over a 4-year period, recently. Association between visual outcome and various preoperative, operative, and postoperative variables was statistically analyzed. Data were analyzed with the paired t-test and the chi square test. Statistical significance was indicated by P < 0.05. The mean interval between the time of injury and IOFB removal was 24 +/- 43.1 days and 27 [53%] eyes underwent IOFB removal within 7 days of the injury. Nine [19.1%] patients achieved a visual acuity of 20/40 or better. An improvement of visual acuity of at least three lines occurred in 21 [44.6%] eyes and the vision remained unchanged in 15 [31.9%] eyes. Postoperative retinal detachment occurred in five [10.6%] eyes. Visual improvement was more likely to occur in eyes with lower levels of presenting visual acuity [P = 0.2]. Visual improvement was not associated with an entry site and IOFB location, lens injury, time to surgery, and pre- and post-operative retinal detachment. At the end of follow up, anatomical success was achieved in 97.9% of eyes. High anatomical success could be achieved after the removal of posterior segment IOFBs by vitrectomy, despite a delay in surgery. Poor visual outcome may be mainly due to the initial ocular injury

[Effects of intra-oral intake of different concentrations of sucrose on biobehavioral pain response to immunizations in infants]

An uncontrolled pain in infants can lead to permanent damage of the components of cognitive growth and development and change in response to painful stimuli. The aim of this study was to compare the effect of oral sucrose%20 and%50 on biobehavioural pain response to hepatitis B virus [HBV] vaccine injection in term newborns. In this triple blind clinical trial study, which was performed in Semnan Amir-Al-Momenin Hospital, 91 term infants were selected and randomly divided into three groups. Two minutes prior to immunization with HBV vaccine by intramuscular injection, 2 ml of 20% or 50% sucrose solution was given to the infants in, experimental groups, while, the infants in the control group were orally received only 2 ml of sterile distilled water. The pain response was measured by using Neonatal Infant Pain Scale [NIPS] tools before the administration of sucrose, immediately after injection and 5 min after injection. The results showed that the administration of 50% sucrose significantly reduces pain response in newborns immediately and 5 minutes after HBV vaccination [P < 0.05]. But the administration of 20% sucrose was effective only 5 minutes after HBV vaccine injection. The administration of 50% sucrose can effectviley reduce the pain due to HBV vaccination in infants.

[Comparing carotid intima-media thickness in type 2 diabetes between patients with and without retinopathy]

Microangiopathy and macroangiopathy frequently coexist in type 2 diabetes mellitus [T2DM]. Both types of the vascular complications share traditional risk factors but it is not clear whether the presence of microangiopathy, such as diabetic retinopathy, constitutes a predictor of atherosclerosis in carotid arteries in patients with the disease. In this study we looked for the association between diabetic retinopathy and intima-media thickness in carotid arteries of patients with T2DM. In this case-control study we examined 100 consecutive patients with T2DM in Rasoul Akram Hospital in Tehran, Iran during 2009-2010. We assessed intima-media thickness of carotid arteries by ultrasonography. All patients underwent ophthalmo-logic examination. Diabetic retinopathy was found in 50 [50%] patients. Intima-media thickness was higher in patients with diabetic retinopathy than those without it [0.77 +/- 0.17 mm vs. 0.71 +/- 0.2 mm, respectively, P=0.041]. Moreover, intima-media thickness was more prevalent in patients with proliferative diabetic retinopathy than patients with non-proliferative form of the disease [0.87 +/- 0.16 mm vs. 0.68 +/- 0.1 mm, respectively, P<0.001]. Diabetic retinopathy seems to be associated with increased intima-media thickness of carotid arteries in T2DM. It may be a common denominator of pathogenesis of microvascular complications and atherosclerosis in T2DM. Evaluations of carotid arteries are to be done by non-invasive methods such as color Doppler sonography for screening and preventing prospective cereberovascular accidents in patients with diabetic retinopathy, especially proliferative retinopathy, in routine ophthalmological examination of patients with T2DM

Pharmacologic vitreolysis

The vitreoretinal interface is involved in a wide range of vitreoretinal disorders and separation of the posterior vitreous face from the retinal surface is an essential part of vitrectomy surgeries. A diverse range of enzymatic and non-enzymatic agents are being studied as an adjunct before or during vitrectomy to facilitate the induction of posterior vitreous detachment. There is a significant body of knowledge in the literature about different vitreolytic agents under investigation for a variety of pathologies involving the vitreoretinal interface which will be summarized in this review

effect of the type of hemodialysis buffer on the QTc interval in Patients on chronic hemodialysis

Identifying the sources of variation in QTc measurements is important for preventing arrhythmias during and after hemodialysis. The present study was designed to determine the correlation between the type of hemodialysis buffer and the changes in QTc interval in patients on chronic hemodialysis. Fifty-nine patients on chronic hemodialysis who referred in winter 2007 to hemodialysis centers of Ghaem and Hashemi Nejad hospitals, in Mashhad, Iran, were divided into two groups according to their last dialysate buffer: acetate or bicarbonate. Electrocardiography, arterial blood gas parameters, serum K+, Na+, ionized calcium, and albumin levels were measured prior to and after hemodialysis in all patients. All arterial blood gas parameters and serum electrolytes concentrations were increased except K+ levels that were significantly decreased with hemodialysis. PCO[3] and QTc intervals were slightly increased in all patients, however this increase was not statistically significant. We found that the type of dialysate affected the QTc interval, HCO[3], base excess, base excess of extra cellular fluid, and base buffer changes with no effect on ionized calcium, pH, PCO[2], and serum albumin concentration. QTc interval was prolonged by using bicarbonate and shortened by using acetate dialysate buffer. We found no correlation between the variations of QTc interval and serum electrolytes or arterial blood gas parameters in either group Bicarbonate buffer use in hemodialysis prolonged QTc interval and acetate buffer shortened it. This effect is independent of serum electrolytes and pH changes during hemodialysis. The effect of bicarbonate buffer is probably due to more tolerability of ultra filtration, more effective edema reduction and augmented body electro-conductivity