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Photocoagulation
Kinds of Photocoagulation Terms modified by Photocoagulation Selected AbstractsAssessment of Proliferating Cell Nuclear Antigen Activity Using Digital Image Analysis in Breast Carcinoma Following Magnetic Resonance-Guided Interstitial Laser PhotocoagulationTHE BREAST JOURNAL, Issue 5 2003Soheila Korourian MD Abstract: This study examines proliferative activity in tumor cells of patients with histologically documented invasive breast carcinoma treated with magnetic resonance-guided interstitial laser photocoagulation (MR-GILP). Immunohistochemical marker for proliferating cell nuclear antigen (PCNA), a nuclear protein abundant in actively proliferating cells, is used. The study demonstrates the effectiveness of MR-GILP in ablating tumor cells of infiltrating breast cancer. The diagnosis of infiltrating breast carcinoma was confirmed by core needle biopsies. Using a specially designed magnetic resonance imaging (MRI) device, rotating delivery of excitation off-resonance (RODEO), tumors were measured ranging from 1.8 to 4.0 cm in greatest dimension. Seven formalin-fixed, paraffin-embedded archival tissues from seven patients with infiltrating carcinoma, status post-MR-GILP, were analyzed. Using PCNA immunoperoxidase (Biomeda Corp.), the proliferative capability of the remaining tumor cells around the focus of laser photocoagulation was determined. The lesions were digitally acquired using a Nikon Eclipse E800 microscope with an automated stage. Images were analyzed using Cool SNAP image editing software (version 1.0). Appropriate thresholds were set for positive staining and limited concentric radial measurements of equal area between all samples were compared at radial millimeter intervals from the center of laser ablation. The integrated area occupied by PCNA-positive cells per radial millimeter from the charcoal site (the center of the laser) increased as the distance from this site increased (a mean average at each radial measurement revealed: at the 1 mm radius the positive integrated area was 0.0024 mm2; at 2 mm, 0.0145 mm2; at 3 mm, 0.0351 mm2; at 4 mm, 0.0696 mm2; at 5 mm, 0.1025 mm2; and at 6 mm, 0.1263 mm2). MR-GILP is an effective mean of ablating breast carcinoma. This treatment option may represent an alternative to lumpectomy for a single lesion ,1 cm, or make patients with two separate lesions eligible for lumpectomy. [source] Treatment of recurrent colorectal liver metastases by interstitial laser photocoagulationBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 3 2000A. Shankar Background: Hepatic resection improves survival in selected patients with colorectal liver metastases. The treatment of recurrent hepatic metastases after resection is controversial. Interstitial laser photocoagulation, performed under local anaesthesia, offers a minimally invasive option to repeat resection. The first series of patients with recurrent colorectal liver metastases treated with photocoagulation is reported. Methods: Nineteen patients (five women and 14 men, median age 57 (range 44,71) years) who developed recurrent colorectal liver metastases after hepatectomy (five with bilateral disease) were treated with photocoagulation between 1993 and 1997. Fifteen patients also received chemotherapy (14 systemic, one hepatic arterial) before photocoagulation. Results: There were no major complications or deaths related to the treatment. Six patients developed minor complications related to the procedure but did not require any form of intervention. Median survival from commencement of photocoagulation was 16 (range 4,36) months. Conclusion: Photocoagulation is a safe, minimally invasive therapy that may be used as an adjunct to chemotherapy and repeat resection in the treatment of recurrent colorectal liver metastases, and may lead to improved survival. © 2000 British Journal of Surgery Society Ltd [source] 2412: Laser and oxygenACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose To evaluate the changes in the retinal oxygen partial pressure (PO2) following photocoagulation as well as the resulting effect of the laser induced improved oxygenation, on the retinal vessels hemodynamics. Methods Measurements of the partial pressure of oxygen (PO2) distribution within the retina in various animal species using oxygen sensitive microelectrodes and evaluation of changes on the retinal vessels reactivity, following laser treatment, gave additional insights concerning photocoagulation mechanisms. Results Preretinal intervascular PO2 , far away from vessels, remain constant in all retinal areas. Intervascular intraretinal PO2 gradually decreases from both the vitreo-retinal interface and the choroid towards the mid-retina. Close to the pigment epithelium, it is significantly higher than at the vitreoretinal interface due to the much higher O2 supply provided by choroidal compaires to retinal circulation. Laser photocoagulation reduces the outer retina O2 consumption and allows O2 diffusion into the inner retina from the choroid raising the PO2 in the inner healthy retinal layers and in the preretinal intervascular normal areas. In this way, laser treatment relieves retinal hypoxia in experimental branch vein occlusion (BRVO). In patients with diabetic retinopathy (DR), the retinal PO2 is also higher in areas previously treated with laser. Following photocoagulation, the resulting reversal of hypoxia, the down-regulation of the VEGF expression, the retinal vasculature constriction and the improvement of the auto-regulatory response to physiological stimuli, all affect favorably both the retinal neovascularisation and macular edema. Conclusion Photocoagulation induces an increase of the inner retinal oxygenation resulting to an improvement of the autoregulatory retinal vessels response. [source] Retinal photocoagulation and oxygenationACTA OPHTHALMOLOGICA, Issue 2009CJ POURNARAS Purpose The clinical role of photocoagulation for the treatment of hypoxia related complications of retinal ischemic microangiopathies is well established. Methods Measurements of the partial pressure of oxygen (PO2) distribution within the the retina in various animal species using oxygen sensitive microelectrodes and evaluation of the retinal vessels reactivity by laser doppler velocimetry gave additional insights concerning photocoagulation mechanisms. Results The PO2 within the vitreo-retinal interface is heterogeneous. Preretinal and trans-retinal PO2 profiles indicate that the preretinal PO2 far away from vessels remain constant in all retinal areas. Intervascular intraretinal PO2 gradually decreases from both the vitreo-retinal interface and the choroid towards the mid-retina. Close to the pigment epithelium, it is significantly higher than at the vitreoretinal interface due to the much higher O2 supply provided by choroidal compaires to retinal circulation. Laser photocoagulation reduces the outer retina O2 consumption and allows O2 diffusion into the inner retina from the choroid raising the PO2 in the inner healthy retinal layers and in the preretinal intervascular normal areas. In this way laser treatment relieves retinal hypoxia in experimental branch vein occlusion (BRVO). In patients with diabetic retinopathy (DR), the retinal PO2 is higher in areas previously treated with laser. Following photocoagulation, the resulting reversal of hypoxia, the retinal vasculature constriction and the improvement of the regulatory response to hyperoxia all affect favorably both the retinal neovascularisation and macular edema. Conclusion Photocoagulation induces an increase of the inner retinal oxygenation reversing the retinal hypoxia and improving the regulatory response of the retinal vessels [source] Photocoagulation for diabetic retinopathy: determinants of patient satisfaction and the patient,provider relationshipACTA OPHTHALMOLOGICA, Issue 3 2005Maneli Mozaffarieh Abstract. Purpose:,To assess satisfaction with photocoagulation treatment in diabetes patients and to investigate how it relates to patient-related characteristics and patients' visual ability. Further, to observe the interaction between physician and patient and suggest ways to improve the patient,provider relationship and, thereby, treatment satisfaction. Methods:,This open longitudinal study included 123 diabetes patients undergoing first photocoagulation treatment for diabetic maculopathy or proliferative retinopathy. The Diabetes Treatment Satisfaction Questionnaire (DTSQ) was completed by all patients. Communication, scheduling and adherence scores were defined for each physician,patient pair. Outcome measures were: the patient's overall satisfaction with laser treatment; the patient's degree of satisfaction in relation to visual results; communication, scheduling and adherence scores, and visual acuity results. Results:,The level of satisfaction after initial photocoagulation treatment was high; 46.4% of patients with proliferative retinopathy and 53.1% with maculopathy scored 31 or higher. Although 69.5% of all patients reported that their expectations of treatment corresponded to their final 9-month visual results, only 8.7% of these patients reported an improvement in visual acuity after 9 months. The number of unwanted actions performed by the patients during treatment were significantly related to the number of unclear instructions given by the physician (Fisher's exact test P < 0.01). Conclusions:,A high level of satisfaction was observed, despite the minimal improvements in visual acuity. Attempts to further improve patient satisfaction might focus on improved education of patients on the possible benefits of laser treatment, greater care in communicating information during treatment, additional nursing support, and additional clerical time to communicate with patients before each appointment. [source] Laser photocoagulation for choroidal neovascular membrane associated with optic disc drusenACTA OPHTHALMOLOGICA, Issue 2 2004Marie N. Delyfer Abstract. Purpose:, To report two cases of choroidal neovascular membrane associated with optic disc drusen which were successfully treated using argon laser photocoagulation. Methods:, Choroidal neovascular complications of optic disc drusen were diagnosed in two of our patients, a 36-year-old woman and a 14-year-old girl. In both cases visual acuity was 20/100 in the affected eye. Fundus examination and angiography revealed a choroidal neovascular membrane. Computer tomography identified bilateral calcified drusen of the optic discs. Photocoagulation of neovascular tissues was immediately performed. Results:, Visual acuity improved progressively, reaching 20/20 10 months after treatment in one case and 20/30 in the other. No recurrence was observed during follow-up. Conclusion:, Early diagnosis and immediate laser photocoagulation of vision-threatening choroidal neovascular membranes associated with optic disc drusen helps stop progression towards the macula and improves longterm visual acuity. [source] Fluorescein angiographic monitoring of corneal vascularization in lipid keratopathyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 1 2004Jayanthi Peter MB BS DO Abstract The use of digital fluorescein corneal angiography to assist argon laser photocoagulation is reported. Photocoagulation was performed on the vascular supply of lipid keratopathy in the left eye of a 44-year-old woman. [source] Long-term review of driving potential following bilateral panretinal photocoagulation for proliferative diabetic retinopathyDIABETIC MEDICINE, Issue 1 2009S. A. Vernon Abstract Aim To determine the necessity for repeated Driver and Vehicle Licensing Agency (DVLA) visual field testing in people with diabetes who have had bilateral panretinal photocoagulation (PRP) for proliferative diabetic retinopathy. Methods A questionnaire survey was conducted of driving history in a cohort of people with diabetes who had been treated with bilateral PRP for proliferative retinopathy between 1988 and 1990. In addition, all similarly eligible subjects attending the diabetic retinal review clinic over a 12-month period who had had laser between 1991 and 2000 were questioned as to their driving status. Results Forty-five surviving patients from the 1988,1990 cohort were eligible and 25 returned the questionnaire (55%). Eight had never driven and 15 (13 with Type 1 diabetes) still held a valid licence, having passed the DVLA field test on a number of occasions. Neither of the two patients who had stopped driving reported failing the DVLA field test as the reason for stopping. All 12 of the patients directly questioned in the clinic were still driving and had passed at least one repeat DVLA test. Conclusions People with Type 1 diabetes who have no further laser treatment for proliferative diabetic retinopathy can expect to retain their UK driving licence for at least 15 years following small-burn PRP, provided they maintain sufficient acuity. [source] Perception of, and anxiety levels induced by, laser treatment in patients with sight-threatening diabetic retinopathy.DIABETIC MEDICINE, Issue 10 2006A multicentre study Abstract Aims To investigate how laser treatment is perceived, in terms of anxiety and awareness, by diabetic patients attending four centres in Northern Italy with specific interest and expertise in diabetic retinopathy, where work settings and flow are organized differently. Methods The Hospital Anxiety and Depression Scale (HADS), Family Apgar-List of Threatening Experiences (FA-LTE), State-Trait Anxiety Inventories 1 and 2 (STAI-1 and STAI-2) questionnaires were completed by 259 patients, 131 waiting for laser treatment and 128 control subejcts awaiting non-intervention visits. Open questions were also asked on whether patients had ever heard the word ,laser' and whether they could describe laser treatment. Results High scores were detected by HADS, STAI-1 and STAI-2 among patients waiting for photocoagulation. Anxiety was greater in women and people with poor schooling. After controlling for centres, gender, previous laser treatment and schooling, HADS and STAI-1 remained significantly lower among persons waiting for non-intervention visits. Having received photocoagulation previously did not modify anxiety. Anxiety was lower in those centres where facilities and resources were more patient-oriented. Most patients could neither describe photocoagulation nor explain why they were about to receive it, but had a negative perception and some described it with words evoking cruelty and pain. Conclusions These data suggest that laser treatment is experienced as an event that causes anxiety. Preoperative education and counselling may help to reduce fear and patients' avoidance of treatment. [source] Relationship between the severity of retinopathy and progression to photocoagulation in patients with Type 2 diabetes mellitus in the UKPDS (UKPDS 52)DIABETIC MEDICINE, Issue 3 2001Uk Prospective Diabetes Study (ukpds) Group Summary Aim to establish the degree to which the severity of retinopathy determines the risk for the need for subsequent photocoagulation in those with newly diagnosed Type 2 diabetes mellitus. Methods Of 5102 patients entered into the UK Prospective Diabetes Study (UKPDS), 3709 had good quality retinal photographs that could be graded at entry. They were followed until the end of the study or until lost to follow-up, or until they received photocoagulation. Retinopathy severity was categorized as no retinopathy, microaneurysms (MA) only in one eye, MA in both eyes or more severe retinopathy features. The risk of photocoagulation was assessed in relation to severity of retinopathy at baseline, 3 and 6 years. Results Of the 3709 patients assessed at entry to the UKPDS, 2316 had no retinopathy. Of these 0.2% needed photocoagulation at 3 years, 1.1% at 6 years and 2.6% at 9 years. Those with MA in one eye only (n = 708) were similar, with 0%, 1.9% and 4.7% needing photocoagulation by 3, 6 and 9 years, respectively. Amongst those who had more retinopathy features at entry (n = 509), 15.3% required photocoagulation by 3 years, and 31.9% by 9 years. When those without retinopathy at 6 years (n = 1579) were examined 3 and 6 years later (9 and 12 years after diagnosis), 0.1% and 1.8% required photocoagulation. Those with more severe retinopathy (n = 775) needed earlier treatment, 6.6% after 3 years and 13.3% after 9 years. The commonest indication for laser therapy was maculopathy, but those with more severe retinopathy were more likely to be treated for proliferative retinopathy and to need both eyes treated. Conclusion Few type 2 diabetic patients without retinopathy progress to photocoagulation in the following 3,6 years, while patients with more severe retinopathy lesions need to be monitored closely. [source] Macular oedema with associated uveitis and cataract following presentation of Type 1 diabetes mellitus in severe ketoacidosisDIABETIC MEDICINE, Issue 4 2000D. Gordon Abstract We present a case of cystoid macular oedema presenting in a newly diagnosed diabetic teenager. She had developed anterior uveitis prior to diabetes and whether this contributed to the subsequent ocular complications remains speculative. The macular changes resolved spontaneously over 6 months without the use of grid laser photocoagulation. [source] Neodymium-YAG Laser for hemangiomas and vascular malformations , long term resultsJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 6 2005Die Behandlung von Hämangiomen und vaskulären Fehlbildungen mit dem Neodymium-YAG-Laser, Langzeitergebnisse Hämangiom; Lasertherapie; Nd:YAG-Laser; vaskuläre Malformation Summary Background: Hemangiomas and vascular malformations are the most common vascular lesions of infancy. Different lasers can be used for treatment. Nd:YAG laser photocoagulation is particularly effective because of its deep penetration into tissue. Patients and methods: Thirty-one patients, aged from three months to 18,years, with voluminous hemangiomas and venous malformations were treated with a cw-neodymium:YAG laser. The quartz fibre was used in percutaneous and intralesional technique. Long-term follow-up data were acquired by clinical control or a patient questionnaire for a maximal period of eight years. Twenty patients could be evaluated. Results: In the group with hemangiomas (n,=,15), three cases showed nearly complete remission (> 90 %), ten cases had a partial reduction in size (50,,,90 %), in one case there was stable disease and in one case tumor growth. In the group with venous malformations (n,=,5) two cases showed an excellent response (> 90 %), one case a moderate response (25,,,50 %) and in two cases there was no improvement. Adverse effects included scars (40 %), hyper- and hypopigmentation (23 %), mild atrophy (20 %) and a wrinkled texture (17 %). After maximal reduction in size, 30 % of the patients were not satisfied with the laser treatment outcome and elected surgical excision of the residual lesion. Conclusions: The neodymium:yttrium aluminium garnet (Nd:YAG) laser with percutaneous or intralesional application technique is a valuable tool for selected patients with hemangiomas and venous malformations. Zusammenfassung Hintergrund: Hämangiome und vaskuläre Malformationen sind die häufigsten Gefäßfehlbildungen in der Kindheit. Eine Therapieoption stellt die Laserbehandlung dar. Der Nd:YAG-Laser ist besonders effektiv aufgrund seiner hohen Eindringtiefe ins Gewebe. Patienten und Methodik: Insgesamt wurden 31,Patienten im Alter zwischen drei Monaten und achtzehn Jahren mit voluminösen Hämangiomen und venösen Malformationen mit einem cw-Neodymium:YAG-Laser behandelt. Die Laserfaser wurde in perkutaner und intraläsionaler Technik angewendet. Die Nachbeobachtung über einen Zeitraum von maximal acht Jahren erfolgte mittels klinischer Kontrollen oder einem Patientenfragebogen. Von den insgesamt 31,Patienten konnten 20 ausgewertet werden. Ergebnisse: In der Gruppe der Patienten mit Hämangiomen zeigten drei Patienten eine fast vollständige Rückbildung (> 90 %), zehn Patienten eine partielle Rückbildung (50,,,90 %), in einem Fall zeigte sich ein unveränderter Befund und bei einem Patienten beobachteten wir weiterhin Wachstum. In der Gruppe der Patienten mit venösen Malformationen zeigten zwei Patienten ein exzellentes Ansprechen (> 90 %), ein Patient ein moderates Ansprechen (25,,,50 %) und bei zwei Patienten kam es zu keiner Verbesserung. Nebenwirkungen beinhalteten Narben (40 %), Hyper- und Hypopigmentierungen (23 %), geringe Atrophie (20 %) und eine Hautfältelung. Nach vollständiger Rückbildung waren 30 % der Patienten unzufrieden mit dem Ergebnis und unterzogen sich einer operativen Entfernung der Residuen. Schlußfolgerungen: Der Nd:YAG-Laser mit perkutaner und intraläsionaler Applikationstechnik stellt eine wirksame Methode zur Behandlung ausgewählter Patienten mit Hämangiomen und venösen Malformationen dar. [source] Mechanistic comparison of blood undergoing laser photocoagulation at 532 and 1,064 nmLASERS IN SURGERY AND MEDICINE, Issue 2 2005John F. Black PhD Abstract Background and Objectives We seek to compare and contrast the mechanisms of blood photocoagulation under 532 and 1,064 nm laser irradiation in vitro in order to better understand the in vivo observations. We also seek to validate a finite element model (FEM) developed to study the thermodynamics of coagulation. Study Design/Materials and Methods We study the photocoagulation of whole blood in vitro at 532 and 1,064 nm using time-domain spectroscopic and optical coherence tomography (OCT)-based imaging techniques. We model the coagulation using an FEM program that includes the latent heat of vaporization (LHV) of water, consideration of the pulse shape of the laser, and the bathochromic shift in the hemoglobin absorption spectrum. Results We find significant similarities in the spectroscopic, chemical, and structural changes occurring in hemoglobin and in the blood matrix during photocoagulation despite the very large difference in the absorption coefficients. The more uniform temperature profile developed by the deeper-penetrating 1,064 nm laser allows us to resolve the structural phase transition in the red blood cells (going from biconcave disc to spherocyte) and the chemical transition creating met-hemoglobin. We find that the RBC morphology transition happens first, and that the met-Hb transition happens at a much higher temperature (,>,90°C) than is found in slow bath heating. The FEM analysis with the LHV constraint and bathochromic shift predicts accurately the imaging results in both cases, and can be used to show that at 1,064 nm there is the potential for a runaway increase in absorption during the laser pulse. Conclusions Photothermally mediated processes dominate the in vitro coagulation dynamics in both regimes despite the difference in absorption coefficients. There is a significant risk under 1,064 nm irradiation of vascular lesions in vivo that the dynamic optical properties of blood will cause runaway absorption and heating. This may in turn explain some recent results at this wavelength where full-thickness burns resulted from laser treatment. Lasers Surg. Med. 36:155,165, 2005. © 2005 Wiley-Liss, Inc. [source] Modification of the LMA no. 1 for diode laser photocoagulation in ex-premature infantsPEDIATRIC ANESTHESIA, Issue 3 2000Article first published online: 9 OCT 200 No abstract is available for this article. [source] Benign pineal cysts in children with bilateral retinoblastoma: A new variant of trilateral retinoblastoma?PEDIATRIC BLOOD & CANCER, Issue 7 2006Maja Beck Popovic MD Abstract Purpose Patients with hereditary retinoblastoma (Rb) develop in 4%,8% a malignant midline tumor called trilateral Rb (TRb). We report in this study on benign pineal cysts observed in patients investigated for TRb. Patients and Methods Between September 1990 and December 2001, 172 patients were screened for TRb. Ninty-five had bilateral, 77 unilateral disease. The median age at diagnosis of Rb was 7 months (range 1,26). Treatment included enucleation, local treatment with cryotherapy or photocoagulation, first-line chemotherapy (CT), thermo-chemotherapy (TCT), Ruthenium plaque, and, rarely, external beam radiation (EBR). Results TRb was found in 5/95 patients (5.3%) with bilateral disease. Interestingly, five other patients (5.3%) presented a pineal cyst on magnetic resonance imaging (MRI). No cysts were recorded in the 77 patients with unilateral disease. This difference was statistically significant (P,<,0.05). The median age at diagnosis of the pineal cyst was 26 months (range 16,80), much younger than reported in literature for healthy children. Four of five patients with TRb died of the disease, while all the patients with pineal cysts remained stable and asymptomatic during a median follow-up of 41 months (range 37,54). Conclusions This report describes benign cystic lesions of the pineal gland in patients with hereditary Rb, suggesting a benign variant of TRb. Underlying possible pathogenetic mechanisms are discussed. © 2005 Wiley-Liss, Inc. [source] Risk factors for visual impairment registration due to diabetic retinopathy in Leeds, 2002,2005PRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 3 2009Diabetes & Endocrinology, H Hayat Specialist Registrar Abstract We undertook a retrospective study of case notes of those patients registered blind or partially sighted due to diabetic retinopathy in the Leeds metropolitan area in the years 2002 and 2005. Both the incidence of visual impairment due to diabetic retinopathy and the relative contribution to total registrations are similar to those observed in other local and national studies. The main risk factors for registered visual impairment were poor glycaemic control prior to ophthalmic review, no prior retinopathy screening, late presentation with symptomatic visual loss, non-compliance with planned review and laser treatment failure. Most of these risk factors are avoidable. Nearly two-thirds of patients diagnosed with diabetes mellitus were being screened for diabetic retinopathy. These figures would suggest that the National Service Framework for Diabetes' proposed coverage of 80% by 2006 and 100% by the end of 2007 is achievable. The duration of diagnosed diabetes mellitus at the time of registration was an average of 16 years in this study. This reflects the slow development of sight-threatening retinopathy and visual loss observed previously. Conventional therapy for diabetic retinopathy with laser photocoagulation reduces the risk of visual loss more effectively than it improves visual function. Despite the increased risk of early worsening of retinopathy seen with intensive glycaemic control in the Diabetes Control and Complications Trial and the UK Prospective Diabetes Study, improved control closer to the time of diagnosis of diabetes mellitus would have helped to provide a sustained reduction in the risk of retinopathy developing or progressing. Both laser treatment failure and non-attendance may limit the benefits of improved screening coverage. Copyright © 2009 John Wiley & Sons. [source] Resolution of mirror syndrome after successful fetoscopic laser photocoagulation of communicating placental vessels in severe twin,twin transfusion syndromePRENATAL DIAGNOSIS, Issue 12 2008Masakazu Matsubara No abstract is available for this article. [source] Assessment of Proliferating Cell Nuclear Antigen Activity Using Digital Image Analysis in Breast Carcinoma Following Magnetic Resonance-Guided Interstitial Laser PhotocoagulationTHE BREAST JOURNAL, Issue 5 2003Soheila Korourian MD Abstract: This study examines proliferative activity in tumor cells of patients with histologically documented invasive breast carcinoma treated with magnetic resonance-guided interstitial laser photocoagulation (MR-GILP). Immunohistochemical marker for proliferating cell nuclear antigen (PCNA), a nuclear protein abundant in actively proliferating cells, is used. The study demonstrates the effectiveness of MR-GILP in ablating tumor cells of infiltrating breast cancer. The diagnosis of infiltrating breast carcinoma was confirmed by core needle biopsies. Using a specially designed magnetic resonance imaging (MRI) device, rotating delivery of excitation off-resonance (RODEO), tumors were measured ranging from 1.8 to 4.0 cm in greatest dimension. Seven formalin-fixed, paraffin-embedded archival tissues from seven patients with infiltrating carcinoma, status post-MR-GILP, were analyzed. Using PCNA immunoperoxidase (Biomeda Corp.), the proliferative capability of the remaining tumor cells around the focus of laser photocoagulation was determined. The lesions were digitally acquired using a Nikon Eclipse E800 microscope with an automated stage. Images were analyzed using Cool SNAP image editing software (version 1.0). Appropriate thresholds were set for positive staining and limited concentric radial measurements of equal area between all samples were compared at radial millimeter intervals from the center of laser ablation. The integrated area occupied by PCNA-positive cells per radial millimeter from the charcoal site (the center of the laser) increased as the distance from this site increased (a mean average at each radial measurement revealed: at the 1 mm radius the positive integrated area was 0.0024 mm2; at 2 mm, 0.0145 mm2; at 3 mm, 0.0351 mm2; at 4 mm, 0.0696 mm2; at 5 mm, 0.1025 mm2; and at 6 mm, 0.1263 mm2). MR-GILP is an effective mean of ablating breast carcinoma. This treatment option may represent an alternative to lumpectomy for a single lesion ,1 cm, or make patients with two separate lesions eligible for lumpectomy. [source] Immediate outcome of twin,twin transfusion syndrome following selective laser photocoagulation of communicating vessels at the NSW Fetal Therapy CentreAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 2 2010N. MERIKI Objective:, To audit the outcome for laser photocoagulation for twin,twin transfusion syndrome (TTTS) as managed by the New South Wales Fetal Therapy Centre (NSW FTC). Methods: A retrospective cohort study. Outcome data were reviewed for referrals between June 2003 and June 2008. The outcome measures included the severity of TTTS at presentation, delivery details (gestational age at delivery, birth weight and Apgar score at 5 min) and perinatal outcome (spontaneous miscarriage, premature rupture of membranes, intrauterine death, placental abruption and neonatal death). Results: Seventy-nine patients were treated with laser therapy for stage I,IV TTTS (median stage III). Median gestational age at treatment was 20 weeks (range 16,25). Median gestational age at delivery was 32 weeks (range 24,40). Survival of at least one baby in this study was 90.7% (88.9% for anterior and 92.1% for posterior placenta), and of both babies was 60.0%. Median birth weight was 1788 g (range 490,3695). Median Apgar score was nine at 5 min. Three women required repeat laser treatment for persistent TTTS. Conclusions: Selective laser photocoagulation of communicating vessels remains the treatment of choice for TTTS. Referrals to the NSW FTC have increased from five cases in the last half of 2003, to 18 cases in the first half of 2008. Local outcome figures at least equal any in the published international literature and support a continued policy of centralised care in Australia. A two-year follow-up study on neonatal outcome for survivors is underway. [source] Treatment of recurrent colorectal liver metastases by interstitial laser photocoagulationBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 3 2000A. Shankar Background: Hepatic resection improves survival in selected patients with colorectal liver metastases. The treatment of recurrent hepatic metastases after resection is controversial. Interstitial laser photocoagulation, performed under local anaesthesia, offers a minimally invasive option to repeat resection. The first series of patients with recurrent colorectal liver metastases treated with photocoagulation is reported. Methods: Nineteen patients (five women and 14 men, median age 57 (range 44,71) years) who developed recurrent colorectal liver metastases after hepatectomy (five with bilateral disease) were treated with photocoagulation between 1993 and 1997. Fifteen patients also received chemotherapy (14 systemic, one hepatic arterial) before photocoagulation. Results: There were no major complications or deaths related to the treatment. Six patients developed minor complications related to the procedure but did not require any form of intervention. Median survival from commencement of photocoagulation was 16 (range 4,36) months. Conclusion: Photocoagulation is a safe, minimally invasive therapy that may be used as an adjunct to chemotherapy and repeat resection in the treatment of recurrent colorectal liver metastases, and may lead to improved survival. © 2000 British Journal of Surgery Society Ltd [source] 2224: Oxygenation of the human retinaACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose Partial pressure of oxygen in the optic nerve and retina is regulated by the intraocular pressure and systemic blood pressure, the resistance in the blood vessels and oxygen consumption of the tissue. The PO2 is autoregulated and moderate changes in intraocular pressure, blood pressure or tissue oxygen consumption do not affect the retinal and optic nerve oxygen tension. Methods If the intraocular pressure is increased above 40 mmHg or the ocular perfusion pressure decreased below 50 mmHg the autoregulation is overwhelmed and the optic nerve becomes hypoxic. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. Medical intervention can affect optic nerve PO2. Lowering the intraocular pressure tends to increase the optic nerve PO2, even though this effect may be masked by the autoregulation when the optic nerve PO2 and perfusion pressure is in the normal range. Results Carbonic anhydrase inhibitors increase retinal PO2 through a mechanism of vasodilatation and lowering of the intraocular pressure. Carbonic anhydrase inhibition reduces the removal of CO2 from the tissue and the CO2 accumulation induces vasodilatation resulting in increased blood flow and improved oxygen supply. This effect is inhibited by indomethacin but not other cyclo-oxygenase inhibitors. Conclusion Carbonic anhydrase inhibitors increase retinal blood flow and increase oxygen delivery. Glaucoma drugs and glaucoma surgery lower intraocular pressure, increase ocular perfusion pressure and blood flow. Demand of oxygen by retinal cells may be reduced through apoptosis and tissue atrophy, as well as active destruction of tissue by laser photocoagulation. [source] 3412: Anti-VEGF and corticosteroids therapy in macular edema secondary to venous occlusionsACTA OPHTHALMOLOGICA, Issue 2010JAC POURNARAS Purpose To assess the evidence on interventions to improve visual acuity (VA) and to treat macular edema (ME) secondary to central (CRVO) and branch retinal vein occlusion (BRVO) Methods Recent randomized studies have evaluated the safety and efficacy of corticosteroids (triamcinolone, dexamethasone) and anti-VEGF therapies (ranibizumab). Score study evaluates preservative-free intravitreal triamcinolone with standard care in BRVO and CRVO. In Geneva study, dexamethasone (DEX) intravitreal implant is compared with sham in BRVO and CRVO. BRAVO and Cruise studies evaluate intraocular injections of ranibizumab in patients with ME following BRVO and CRVO, respectively. Results In SCORE study, there was no difference identified in visual acuity at 12 months for the standard care group compared with the triamcinolone groups in BRVO patients. Intravitreal triamcinolone is superior to observation for treating vision loss associated with ME secondary to CRVO. Improvements in BCVA with DEX implant were seen in patients with BRVO and CRVO, although the patterns of response differed. Intraocular injections of 0.3 mg or 0.5 mg ranibizumab provided rapid, effective treatment for ME following BRVO and CRVO Conclusion Grid photocoagulation remains the standard care for patients with vision loss associated with ME secondary to BRVO. Intravitreal triamcinolone is superior to observation for treating vision loss associated with ME secondary to CRVO. Dexamethasone intravitreal implant can both reduce the risk of vision loss and improve the speed and incidence of visual improvement in eyes with ME secondary to BRVO or CRVO. Anti-VEGF therapies represent new therapeutical option in the treatment of ME secondary to BRVO and CRVO. Further randomized studies are needed [source] 2411: Clinical effect of retinal photocoagulationACTA OPHTHALMOLOGICA, Issue 2010F BANDELLO [source] 2412: Laser and oxygenACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose To evaluate the changes in the retinal oxygen partial pressure (PO2) following photocoagulation as well as the resulting effect of the laser induced improved oxygenation, on the retinal vessels hemodynamics. Methods Measurements of the partial pressure of oxygen (PO2) distribution within the retina in various animal species using oxygen sensitive microelectrodes and evaluation of changes on the retinal vessels reactivity, following laser treatment, gave additional insights concerning photocoagulation mechanisms. Results Preretinal intervascular PO2 , far away from vessels, remain constant in all retinal areas. Intervascular intraretinal PO2 gradually decreases from both the vitreo-retinal interface and the choroid towards the mid-retina. Close to the pigment epithelium, it is significantly higher than at the vitreoretinal interface due to the much higher O2 supply provided by choroidal compaires to retinal circulation. Laser photocoagulation reduces the outer retina O2 consumption and allows O2 diffusion into the inner retina from the choroid raising the PO2 in the inner healthy retinal layers and in the preretinal intervascular normal areas. In this way, laser treatment relieves retinal hypoxia in experimental branch vein occlusion (BRVO). In patients with diabetic retinopathy (DR), the retinal PO2 is also higher in areas previously treated with laser. Following photocoagulation, the resulting reversal of hypoxia, the down-regulation of the VEGF expression, the retinal vasculature constriction and the improvement of the auto-regulatory response to physiological stimuli, all affect favorably both the retinal neovascularisation and macular edema. Conclusion Photocoagulation induces an increase of the inner retinal oxygenation resulting to an improvement of the autoregulatory retinal vessels response. [source] 2414: Laser and vitrectomyACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose Modern vitreous surgery involves a variety of treatment options in addition to vitrectomy itself, such as photocoagulation, anti-VEGF drugs, intravitreal steroids and release of vitreoretinal traction. A full understanding of these treatment modalities allows sensible combination of treatment options. Methods Vitrectomy reduces the risk of retinal neovascularization, while increasing the risk of iris neovascularization, reduces macular edema and stimulates cataract formation. These clinical consequences may be understood with the help of classical laws of physics and physiology. The laws of Fick, Stokes-Einstein and Hagen-Poiseuille state that molecular transport by diffusion or convection is inversely related to the viscosity of the medium. When the vitreous gel is replaced with less viscous saline, the transport of all molecules, including oxygen and cytokines, is facilitated. Oxygen transport to ischemic retinal areas is improved, as is clearance of VEGF and other cytokines from these areas, thus reducing edema and neovascularization. At the same time, oxygen is transported faster down a concentration gradient from the anterior to the posterior segment, while VEGF moves in the opposite direction, making the anterior segment less oxygenated and with more VEGF, stimulating iris neovascularization. Results Retinal photocoagulation has also repeatedly been shown to improve retinal oxygenation. Oxygen naturally reduces VEGF production and improves retinal hemodynamics. The VEGF-lowering effect of photocoagulation and vitrectomy can be augmented with anti-VEGF drugs and the permeability effect of VEGF reduced with corticosteroids Conclusion Vitrectomy and laser retinal treatment both improve oxygenation of the ischemic retina, reduce VEGF formation and thereby reduce neovascularisation and edema. [source] Steroid injection in addition to macular laser grid photocoagulation in diabetic macular oedema: a systematic reviewACTA OPHTHALMOLOGICA, Issue 4 2010Daan Steijns Abstract. Objectives:, This study aimed to evaluate the evidence for the effects of steroid injection in addition to macular laser grid (MLG) photocoagulation versus those of MLG photocoagulation alone on visual acuity (VA) in patients with diabetic macular oedema (DMO). Methods:, An extensive literature search in Medline (PubMed), Experta Medica (EMBASE) and the Cochrane Library (CENTRAL) using synonyms for MLG photocoagulation, steroid injection and DMO found 181 articles. Of the articles that met selection criteria, three studies in which patients receiving MLG photocoagulation were randomized to additional pretreatment with steroids provided the best available evidence. In addition to VA, central foveal thickness (CFT) was measured at baseline and at 6 months in all three studies. Results:, Two studies, with total populations of 73 and 42 eyes, respectively, reported no additional effect of steroid injection on VA. One study, with a total of 41 eyes, reported a beneficial effect of pretreatment with steroids on VA of , 0.21 ETDRS logMAR units. All three studies reported larger reductions in CFT in eyes pretreated with steroids, the smallest of which was 64 ,m. Conclusions:, Although there is a greater reduction in CFT in eyes pretreated with steroids, this does not consistently result in higher VA. The literature search does not provide sufficiently strong evidence to recommend steroid injection before MLG photocoagulation in DMO. [source] Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP): 24-month experience with telemedicine screeningACTA OPHTHALMOLOGICA, Issue 3 2010Yohko Murakami Abstract. Purpose:, To report the 24-month experience of the Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) telemedicine initiative. Methods:, Retrospective analysis of the SUNDROP archival data gathered between 1 December 2005 and 30 November 2007 to evaluate this diagnostic technology for ROP screening. One hundred and sixty consecutively enrolled infants meeting ROP examination criteria were screened with the RetCam II and evaluated by the SUNDROP reading centre at Stanford University. Nurses obtained five or six images in each eye. All patients also received a dilated examination within 1 week of discharge. Outcomes included treatment-warranted retinopathy of prematurity (TW-ROP) and anatomical outcomes. Results:, In the initial 24-month period, the SUNDROP telemedicine initiative has not missed any TW-ROP. A total of 160 infants (320 eyes) were imaged, resulting in 669 exams and 7556 images. Seven infants were identified with TW-ROP; six underwent laser photocoagulation and one regressed spontaneously. The sensitivity was 100%, with specificity of 99.4%. No patient progressed to retinal detachment or other adverse outcomes. Conclusion:, The SUNDROP telemedicine screening initiative for ROP has been proven to have a high degree of sensitivity and specificity for the identification of treatment-warranted disease. All cases of treatment-warranted disease were captured. There were no adverse outcomes. [source] Intravitreal anti-vascular endothelial growth factor therapy with bevacizumab for tuberous sclerosis with macular oedemaACTA OPHTHALMOLOGICA, Issue 3 2010Wataru Saito Abstract. Purpose:, To describe two patients with macular oedema secondary to tuberous sclerosis complex (TSC) who were treated with intravitreal bevacizumab injection. Methods:, Interventional case reports. Bevacizumab 1.25 mg was injected into the vitreous of two patients with TSC-associated macular oedema / exudative retinal detachment. Vascular endothelial growth factor (VEGF) concentration in the vitreous fluid was measured by enzyme-linked immunosorbent assay (ELISA) in one of these patients. Results:, Patient 1: a 22-year-old woman with TSC was diagnosed as having multiple retinal hamartomas in both eyes. Eleven years later, the patient developed macular oedema with epiretinal membrane formation in the right eye. The patient underwent pars-plana vitrectomy with retinal photocoagulation for retinal tumours. VEGF concentration in the vitreous fluid was high compared to that in patients without retinal vascular diseases. Recurrent macular oedema disappeared by intravitreal injection of bevacizumab. Patient 2: a 32-year-old woman with TSC-associated retinal hamartoma, temporally showing macular exudative retinal detachment, developed neovascularization originated from the tumour. By intravitreal bevacizumab injection, the tumour size reduced markedly with regression of neovascularization. Conclusion:, These results suggest that VEGF derived from retinal hamartomas causes macular oedema associated with TSC. Intravitreal injections of bevacizumab may be a useful therapeutic option for macular oedema secondary to TSC. [source] Multifocal electroretinography amplitudes increase after photocoagulation in areas with increased retinal thickness and hard exudatesACTA OPHTHALMOLOGICA, Issue 2 2010Monica Lövestam-Adrian Abstract. Purpose:, This study aimed to evaluate local response on multifocal electroretinography (mfERG) and to assess retinal thickness with optical coherence tomography (OCT) after focal laser treatment in areas with retinal oedema and exudates in patients with diabetic retinopathy. Methods:, Twelve diabetes patients (aged 60 ± 14 years, diabetes duration 16 ± 8 years) treated with focal or grid photocoagulation in areas with retinal oedema and/or exudates underwent mfERG and OCT before and 3 months after treatment. The average thickness (in ,m) in any of the nine sectors (defined according to the ETDRS) treated with photocoagulation was measured. Amplitudes and implicit times were analysed in corresponding areas on the mfERG. Results:, Mean mfERG amplitudes increased after photocoagulation (21.5 ± 8.0 nV/deg2 versus 16.8 ± 6.1 nV/deg2; p = 0.012), whereas no difference was seen in implicit times. Mean OCT values in the treated regions were lower at follow-up (272 ± 23 ,m versus 327 ± 79 ,m; p = 0.013). No correlation was seen between changes in mfERG response and changes in OCT values. The decrease in retinal thickness was correlated with the number of laser spots applied (p = 0.002). Conclusions:, Focal argon laser treatment is effective in reducing retinal thickness. In addition, treated areas tend to show improved retinal function as demonstrated by increased amplitudes on mfERG. [source] Early indirect laser photocoagulation to induce regression of retinal vascular abnormalities in incontinentia pigmentiACTA OPHTHALMOLOGICA, Issue 2 2010Figen Batioglu No abstract is available for this article. [source] | ||||||||||