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1.
J Econ Entomol ; 113(2): 872-881, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-31901943

RESUMEN

In cucurbit crops such as watermelon, implementation of integrated pest management (IPM) is important due to the high reliance on bees for fruit set, along with mounting evidence of the risks of insecticide use associated with pollinator health. Yet, IPM adoption, on-farm pesticide use behaviors, their costs, and impacts on the primary insect pest (striped cucumber beetle, Acalymma vittatum F.) are poorly known in one of the key watermelon-growing regions, the Midwestern United States. To better understand how to implement IPM into watermelon production, we assessed pest management practices on commercial watermelon farms using 30 field sites in Indiana and Illinois over 2 yr in 2017 and 2018. Across all sampling dates, beetles never crossed the economic threshold of five beetles/plant at any farm and most were maintained at densities far below this level (i.e., <1 beetle/plant). Moreover, we documented a wide range of insecticide inputs (mean ca. 5 applications per field per season; max. 10 applications) that were largely dominated by inexpensive foliar pyrethroid sprays; however, insecticide application frequency was poorly correlated with pest counts, suggesting that most of these applications were unnecessary. We calculated that the cost of the average insecticide program far exceeds the cost of scouting, and thus IPM is estimated to save growers ca. $1,000 per field under average conditions (i.e., field size, insecticide cost). These data strongly indicate that current management practices on commercial farms in the Midwest would benefit from implementing more threshold-based IPM programs with potential increases in both farm profitability and pollination services.


Asunto(s)
Citrullus , Escarabajos , Cucumis sativus , Insecticidas , Animales , Illinois , Indiana , Control de Insectos , Medio Oeste de Estados Unidos
2.
Eye (Lond) ; 28(3): 290-5, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24336295

RESUMEN

PURPOSE: To analyze 12- and 24-month visual acuity, intraocular pressure, and complications associated with combined pars plana vitrectomy (PPV) and glaucoma tube shunt placement in eyes with glaucoma. PATIENTS AND METHODS: A retrospective chart review was performed of patients with advanced glaucoma who underwent combined PPV and tube shunt surgery from 2006 to 2010. A minimum of 12 months of follow-up was required for their inclusion in the study. Visual acuity, intraocular pressure, complications, and number of glaucoma medications at 1 and 2 years postoperatively were analyzed. RESULTS: Twenty-eight eyes met the inclusion and exclusion criteria. Baseline visual acuity was 20/200 or worse in 14/28 eyes (50.0%) and 20/40 or better in 2/28 eyes (7.1%). Visual acuity remained 20/200 or worse in 50.0% (P=0.921) and 44.4% (P=0.973) of eyes after 1 and 2 years postoperatively, respectively. At baseline, the mean intraocular pressure was 30.4 mm Hg. There was significant improvement in mean IOP at 1 year (14.7 mm Hg, P=0.001) and at 2 years (15.2 mm Hg, P=0.001) postoperatively. Baseline number of glaucoma medications averaged 3.0±1.09 (SD), and improved to 1.8±1.28 (SD) at 1 year (P=0.0002) and to 1.4±1.33 at 2 years (P<0.0001) postoperatively. CONCLUSION: In this retrospective interventional case series, surgical management of advanced glaucoma with a combination of PPV and glaucoma tube shunt resulted in significantly reduced IOP and glaucoma medications at 1 and 2 years postoperatively.


Asunto(s)
Implantes de Drenaje de Glaucoma , Glaucoma/cirugía , Vitrectomía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Terapia Combinada , Femenino , Estudios de Seguimiento , Glaucoma/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Técnicas de Sutura , Tonometría Ocular , Agudeza Visual/fisiología , Adulto Joven
3.
Eye (Lond) ; 25(8): 1016-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21587275

RESUMEN

UNLABELLED: AIMS OR PURPOSE: To determine the rate of retinal tears (RTs) after posterior vitreous detachment (PVD) and vitreous hemorrhage (VH) in patients on systemic anticoagulants. METHODS: In all, 260 eyes of 260 patients with an acute PVD and VH were followed for evidence of an RT or detachment. Patients were divided into those taking systemic anticoagulants and those not taking anticoagulants. RESULTS: A total of 137 patients (53%) were taking anticoagulants, 123 (47%) were not. Overall, 72% of patients not taking any anticoagulant had evidence of an RT, whereas 46% of patients taking an anticoagulant had an RT (P-value 0.0002). Also, 37% of patients not taking an anticoagulant had a retinal detachment (RD), whereas 23% of patients taking any anticoagulant had an RD (P-value 0.01). CONCLUSIONS: In patients with an acute PVD and VH using anticoagulants, RTs and RDs were common. Anticoagulation status may be an important contributing factor in predicting the incidence of an RT or detachment.


Asunto(s)
Anticoagulantes/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Perforaciones de la Retina/inducido químicamente , Desprendimiento del Vítreo/inducido químicamente , Hemorragia Vítrea/inducido químicamente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
4.
Environ Entomol ; 36(2): 287-96, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17445363

RESUMEN

As part of a program to minimize the accidental transportation of Japanese beetles (Popillia japonica) through cargo aircraft to areas where they are not established, a 4-yr trapping project was initiated to study the relative distribution and dynamics of the beetles along a trap line around the Indianapolis International Airport. Land use influence on beetle abundance (trap catch) was assessed using a geographic information system. Trap catch was consistently high in some locations and low in others. In general, high trap catches occurred near agronomic land planted with corn or soybeans, which are both preferred hosts of adult beetles. Low trap catches generally occurred in areas lacking preferred host plants. The amount of agronomic land within 500 m of the traps was always positively correlated with trap catch. Average trap catches were highly correlated by location from year to year, indicating stability of the relative distribution of the beetles along the trap line. Because high trap catches consistently occurred in the same locations, it can be inferred that trapping can be an effective method to monitor Japanese beetle populations. Taking airport-owned agronomic land out of corn and soybean production near the cargo terminals may reduce beetle activity in these areas.


Asunto(s)
Agricultura/métodos , Escarabajos/fisiología , Control de Insectos/métodos , Transportes , Animales , Escarabajos/crecimiento & desarrollo , Demografía , Femenino , Sistemas de Información Geográfica , Control de Insectos/instrumentación , Masculino , Dinámica Poblacional , Glycine max/parasitología , Zea mays/parasitología
5.
Am J Ophthalmol ; 132(1): 117-20, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11438070

RESUMEN

PURPOSE: To report an HIV-negative lymphoma patient who developed progressive outer retinal necrosis syndrome and who had a good visual outcome after treatment with two-drug antiviral therapy and intravenous immunoglobulin. METHODS: Case report. RESULTS: A 43-year-old man with small lymphocytic lymphoma was diagnosed with progressive outer retinal necrosis in his left eye. Treatment was initiated with intravenous foscarnet and ganciclovir as well as intravenous gammaglobulin at a dose of 0.5 gm/kg per day for 5 days. On the second hospital day he was started on decadron 4 mg orally four times daily. No further posterior retinitis progression was observed despite severe immunosuppression. Visual acuity remained stable at 20/30 with 10 months' follow-up. CONCLUSIONS: The benefit of using gammaglobulin in progressive outer retinal necrosis is unknown. Given the rapid improvement seen in this patient's retinitis, it may be reasonable to consider the use of gammaglobulin in other cases of infectious retinitis in immunocompromised patients.


Asunto(s)
Herpes Zóster Oftálmico/etiología , Leucemia Linfocítica Crónica de Células B/complicaciones , Síndrome de Necrosis Retiniana Aguda/etiología , Adulto , Antivirales/uso terapéutico , Quimioterapia Combinada , Foscarnet/uso terapéutico , Ganciclovir/uso terapéutico , Herpes Zóster Oftálmico/diagnóstico , Herpes Zóster Oftálmico/tratamiento farmacológico , Herpesvirus Humano 3/fisiología , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Masculino , Síndrome de Necrosis Retiniana Aguda/diagnóstico , Síndrome de Necrosis Retiniana Aguda/tratamiento farmacológico , Resultado del Tratamiento , Agudeza Visual
6.
Ophthalmology ; 108(7): 1187-92, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11425673

RESUMEN

OBJECTIVE: To determine the efficacy and safety of indocyanine green (ICG)-assisted retinal internal limiting membrane (ILM) peeling during macular hole repair. DESIGN: Interventional, noncomparative, prospective case series. PARTICIPANTS: Twenty-four consecutive patients (24 eyes) with stage 3 or 4 macular holes. INTERVENTION: All eyes underwent a pars plana vitrectomy, including peeling of the posterior cortical hyaloid when necessary. Indocyanine green dye (0.5%) was instilled into the posterior vitreous cavity over the macula and left in place for 3 to 5 minutes. After removal of the ICG, the retinal ILM was peeled. Medium- to long-acting gas tamponade was used in all cases, and all patients were asked to position face down for 1 to 2 weeks. MAIN OUTCOME MEASURES: Intraoperative staining properties of ICG, technical ease of peeling of the retinal ILM, postoperative anatomic results, visual acuity, and complications were recorded. RESULTS: Indocyanine green stained the retinal ILM, but did not stain the underlying retina. Indocyanine green staining greatly facilitated the surgeons' ability to visualize and peel the ILM in each case. Peeled tissue was sent for both light and electron microscopic studies, which confirmed that the ICG-stained tissue was truly retinal ILM. Patients were observed after surgery for an average of 123 days (range, 23-195 days). Anatomic closure of the macular hole was achieved in 21 eyes (88%) with a single surgery. Visual acuity improved in 23 of 24 patients (96%) after surgery. There were no intra- or postoperative complications related to ICG use, and there was no clinical or fluorescein angiographic evidence of ICG toxicity. CONCLUSIONS: Indocyanine green stains the retinal ILM. This property facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina. Indocyanine green staining of the ILM appears to be a safe and useful adjunct in vitreous surgery for macular hole repair.


Asunto(s)
Membrana Basal/cirugía , Colorantes , Verde de Indocianina , Perforaciones de la Retina/cirugía , Coloración y Etiquetado/métodos , Vitrectomía , Adulto , Anciano , Membrana Basal/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Posición Prona , Estudios Prospectivos , Resultado del Tratamiento , Agudeza Visual , Vitrectomía/métodos
7.
Am J Ophthalmol ; 130(3): 364-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11020423

RESUMEN

PURPOSE: To evaluate the echographic features of medulloepithelioma that may assist in establishing the diagnosis. METHODS: Retrospective review identified four eyes with medulloepithelioma studied with echography. Clinical records, echographic findings, histopathologic tumor features, and the clinical course were reviewed. RESULTS: The initial preoperative diagnosis of medulloepithelioma was uncertain, based on clinical findings alone in three cases but was accurate when echographic findings were combined with clinical findings in all four cases. Cysts posterior to the iris were detected on clinical examination in only two cases, but were revealed on echography in all four cases. Additional echographic findings included irregular high internal reflectivity (n = 4), irregular tumor surface (n = 3), molding around intraocular structures (n = 3), and internal vascularity (n = 2). CONCLUSIONS: The diagnosis of medulloepithelioma is not always apparent on clinical examination alone. Echographic findings of a highly reflective, irregularly structured tumor with associated cystic changes involving the ciliary body region may help establish a presumed diagnosis of medulloepithelioma.


Asunto(s)
Cuerpo Ciliar/diagnóstico por imagen , Neoplasias Neuroepiteliales/diagnóstico por imagen , Neoplasias de la Úvea/diagnóstico por imagen , Segmento Anterior del Ojo/diagnóstico por imagen , Segmento Anterior del Ojo/patología , Niño , Preescolar , Cuerpo Ciliar/patología , Cuerpo Ciliar/cirugía , Femenino , Humanos , Recién Nacido , Iris/patología , Iris/cirugía , Masculino , Neoplasias Neuroepiteliales/patología , Neoplasias Neuroepiteliales/cirugía , Ultrasonografía , Neoplasias de la Úvea/patología , Neoplasias de la Úvea/cirugía
9.
Ophthalmology ; 107(11): 2010-4, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11054324

RESUMEN

OBJECTIVE: To determine whether indocyanine green (ICG) stains and facilitates peeling of the retinal internal limiting membrane (ILM). To investigate the different staining properties of the posterior cortical hyaloid, retinal ILM, and the retina after ILM removal. DESIGN: Autopsy eye study. MATERIALS: Eleven human cadaveric eyes. METHODS: Open sky vitrectomy including removal of the posterior cortical vitreous was performed. A 0.5% ICG solution was then injected into the posterior vitreous cavity over the macula. The dye was allowed to settle on the macula for 5 minutes and was then removed by mechanical aspiration. Peeling of the ILM was initiated with a bent needle and completed with intraocular forceps. Specimens were submitted for light and electron microscopy. MAIN OUTCOME MEASURES: Staining properties and ease of peeling of retinal ILM were evaluated. Retinal ILM removal was confirmed by histopathologic and electron microscopic examination. RESULTS: ICG contact with the retinal surface resulted in bright green staining of the ILM. This stain greatly facilitated ILM peeling by improving direct visualization of the membrane. The underlying retina did not stain, thus providing a clear distinction between the stained ILM and the unstained retina. Continuous circular peeling of the ILM was easily completed with this technique. Light microscopic and ultrastructural studies confirmed removal of the ILM. CONCLUSIONS: ICG solution distinctly stains the nearly invisible retinal ILM in human cadaveric eyes. ICG staining greatly facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina.


Asunto(s)
Colorantes , Técnicas de Diagnóstico Oftalmológico , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/cirugía , Verde de Indocianina , Coloración y Etiquetado/métodos , Membrana Basal/cirugía , Membrana Basal/ultraestructura , Humanos
10.
J Glaucoma ; 9(4): 311-6, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10958604

RESUMEN

PURPOSE: To review the authors' experience in the management of aphakic or pseudophakic patients without an intact posterior capsule who had undergone glaucoma implant surgery complicated by vitreous incarceration in the tube, resulting in increased intraocular pressure or combined rhegmatogenous and tractional retinal detachment. METHODS: Retrospective review of the clinical features, treatment, and outcomes of eight patients who had vitreous incarceration in a glaucoma implant drainage tube. In each patient, a model 425 (7 patients) or model 350 (1 patient) Baerveldt glaucoma implant was used. RESULTS: Vitreous incarceration in the tube was first diagnosed 1 day to 49 weeks after surgery (mean, 7.5 weeks; median, 1 week). The interval between glaucoma implant surgery and pars plana vitrectomy ranged from 22 to 365 days (mean, 125 days). Before management with pars plana vitrectomy or neodymium:yttrium-aluminum-garnet laser vitreolysis, intraocular pressure ranged from 25 to 62 mm Hg (mean, 40 mm Hg). Four patients were initially treated with neodymium:yttrium-aluminum-garnet laser vitreolysis, which was successful in only one patient. Six patients were successfully treated with pars plana vitrectomy, and one patient declined surgery. Follow-up after treatment of the incarceration ranged from 5 weeks to 15 months (mean, 8.3 months). After pars plana vitrectomy, intraocular pressure ranged from 9 to 24 mm Hg (average, 14 mm Hg). Postoperative visual acuity remained within one line of the preoperative visual acuity in each of the six patients undergoing pars plana vitrectomy. CONCLUSIONS: Pars plana vitrectomy is effective in managing vitreous incarceration in glaucoma implant tubes. Previous anterior vitrectomy does not prevent incarceration.


Asunto(s)
Oftalmopatías/cirugía , Implantes de Drenaje de Glaucoma , Terapia por Láser , Falla de Prótesis , Vitrectomía/métodos , Cuerpo Vítreo/patología , Adulto , Anciano , Oftalmopatías/etiología , Oftalmopatías/patología , Glaucoma/cirugía , Humanos , Presión Intraocular , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Cuerpo Vítreo/cirugía
11.
J Econ Entomol ; 93(3): 763-8, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10902328

RESUMEN

Studies were conducted to evaluate the toxicity of insecticides to adult Diadegma insulare (Cresson) and its host the diamondback moth, Plutella xylostella (L.). Leaf-dip and direct-dip bioassays for diamondback moth larvae and residual bioassays for adults of diamondback moth and D. insulare were used to assess mortalities. Larval mortalities at field rates were significantly higher with carbaryl, permethrin, spinosad, and tebufenozide when compared with Bacillus thuringiensis, or imidacloprid in the larval-dip bioassay 72 h after treatment. In the leaf-dip and residual bioassays, both permethrin and spinosad caused 100% mortalities to diamondback moth larvae and adults, respectively, 72 h after treatment. Of all the materials tested, only B. thuringiensis and tebufenozide were not toxic to D. insulare 24 h after treatment. Spinosad was not toxic to D. insulare 30 min after treatment. However, 100% mortality was observed 8 h after treatment.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Avispas , Animales , Bacillus thuringiensis , Carbaril , Hidrazinas , Imidazoles , Control de Insectos/métodos , Larva , Mariposas Nocturnas/parasitología , Neonicotinoides , Nitrocompuestos , Permetrina , Piretrinas
12.
J Control Release ; 55(2-3): 281-95, 1998 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-9795083

RESUMEN

A prototype multiple-drug delivery implant has been developed for the intraocular management of proliferative vitreoretinopathy (PVR). Because of the recurrent nature of the disease, PVR causes blindness in approximately 7% of patients who have undergone retinal re-attachment surgery. The poly(dl-lactide-co-glycolide) 50/50 (PLGA) implant consists of three cylindrical segments, each of which contains one of the following drugs: 5-fluorouridine (5FUrd, an antimetabolite), triamcinolone (Triam, a corticosteroid), and human recombinant tissue plasminogen activator (t-PA, a thrombolytic agent). The device can be inserted through a 20-gauge syringe needle into the vitreous body of the eye. The implant also possesses a PLGA coating over the t-PA-containing terminal segment, which creates a lag-time to deliver t-PA when most needed and to decrease the risk of postoperative bleeding. Two methods of cylinder fabrication were investigated: heat and solvent extrusion. The release behavior of several drugs was examined as a function of the processing variables including: extrusion method, drug loading, polymer molecular weight, and drug particle size. The presence of either the organic solvent (acetone) during processing or a highly water-soluble drug (5FUrd) in the formulation increased the polymer porosity, which in turn, increased the drug release-rate. Drug loading effects were consistent with percolation concepts, and a low-molecular-weight PLGA (e.g., Mw=42000 for inherent viscosity=0.58 dl/g) was desirable to produce controlled release close to one month. Based on pharmacological and pharmacokinetic data of these compounds and our clinical experience with this disease, several design criteria for a combined implant were devised. Optimal cylindrical segments from the formulation studies were selected and combined in series to form a contiguous implant. After successful combination and coating procedures were developed, prototype implants were prepared. From the 3-drug prototype, 5FUrd and Triam were released approximately 1 microgram/day for over 4 weeks and 10-190 microgram/day over 2 weeks, respectively. The solvent-extrusion procedure did not significantly alter the stability of the encapsulated t-PA (>94+/-5% serine protease activity after preparation). After a lag-time of approximately 2 days, t-PA was released active at a rate of approximately 0.2-0.5 microgram/day in approximately 2 weeks. The release characteristics from the combined implant largely met our initial design criteria. Hence, controlled-release implants of this kind may have potential use for intraocular treatment of PVR.


Asunto(s)
Implantes de Medicamentos , Ojo , Activador de Tejido Plasminógeno/administración & dosificación , Triamcinolona/administración & dosificación , Uridina/análogos & derivados , Vitreorretinopatía Proliferativa/tratamiento farmacológico , Cromatografía Líquida de Alta Presión , Humanos , Microscopía Electrónica de Rastreo , Peso Molecular , Tamaño de la Partícula , Polímeros , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapéutico , Activador de Tejido Plasminógeno/farmacocinética , Activador de Tejido Plasminógeno/uso terapéutico , Triamcinolona/farmacocinética , Triamcinolona/uso terapéutico , Uridina/administración & dosificación , Uridina/farmacocinética , Uridina/uso terapéutico
13.
Ophthalmology ; 105(9): 1765-9, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9754189

RESUMEN

OBJECTIVE: The objective of the study was to determine the long-term outcome of patients with uveitis who underwent extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PCIOL) implantation. DESIGN: Retrospective review. PARTICIPANTS: Twenty-eight patients (36 eyes). INTERVENTION: Extracapsular cataract extraction and PCIOL implantation. MAIN OUTCOME MEASURES: Level of best-corrected Snellen visual acuity, change in visual acuity, length of follow-up, long-term findings, and complications. RESULTS: In long-term follow-up (mean, 81.4 months), 94% of eyes had visual acuity improvement compared with preoperative levels. Average change in visual acuity for all eyes was an improvement of 6.4 Snellen lines; 75% of eyes were 20/40 or better. The prevalences of cystoid macular edema (CME), epiretinal membrane (ERM), and posterior capsule opacification (PCO) were 56%, 56%, and 58%, respectively. CONCLUSIONS: Patients with uveitis who are treated with ECCE with PCIOL implantation can have successful visual results in long-term follow-up despite the prevalence of PCO or macular abnormalities such as CME and ERM.


Asunto(s)
Extracción de Catarata , Catarata/complicaciones , Implantación de Lentes Intraoculares , Uveítis Anterior/complicaciones , Uveítis Posterior/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Lentes Intraoculares , Masculino , Polimetil Metacrilato , Complicaciones Posoperatorias , Estudios Retrospectivos , Agudeza Visual
14.
Am Heart J ; 136(2): 269-75, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9704689

RESUMEN

OBJECTIVES: We evaluated global and segmental left ventricular (LV) mass and LV mass/volume ratio in patients with LV dysfunction receiving angiotensin-converting enzyme (ACE) inhibitor therapy after acute myocardial infarction (MI). BACKGROUND: ACE inhibitors attenuate LV dilatation and compensatory hypertrophy after acute MI in animal models. However, LV remodeling in patients after acute MI has been largely defined on the basis of changes in chamber volume alone. METHODS AND RESULTS: Twenty-nine patients with LV ejection fraction <40% received the ACE inhibitor ramipril (range 2.5 to 20 mg/day) within 5 days of their first Q-wave MI. Magnetic resonance imaging was performed at baseline and at 3 months, providing global and regional LV volumes and mass from summated serial short-axis slices. Mean arterial blood pressure was unchanged from baseline to 3-month follow-up (89 +/- 10 to 92 +/- 17 mm Hg). LV mass decreased (90 +/- 25 to 77 +/- 21 gm/m2, p < 0.0005) as LV end-diastolic volumes increased (65 +/- 13 to 73 +/- 22 ml/m2, p < 0.01). Global LV mass to volume ratio decreased from 1.40 +/- 0.28 to 1.08 +/- 0.18 gm/ml (p < 0.0001), as did circumferential wall thickness to volume ratio of noninfarcted myocardium at the base of the LV (0.06 +/- 0.02 to 0.05 +/- 0.02 mm/ml, p < 0.001). LV ejection fraction increased from 35 +/- 6 to 40 +/- 9% (p < 0.001) in the presence of an increase in calculated end-systolic wall stress (185 +/- 57 to 227 +/- 54 gm/cm2, p < 0.01). CONCLUSIONS: ACE inhibitor therapy was associated with improved LV function in the face of a decrease in mass to volume ratio of the LV as well as a decrease in wall thickness to volume ratio of noninfarcted myocardium. Whether ACE inhibitor therapy had direct or indirect effects on these changes in LV mass and function are open questions that require further investigation.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Volumen Cardíaco/efectos de los fármacos , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Infarto del Miocardio/tratamiento farmacológico , Ramipril/uso terapéutico , Volumen Sistólico/efectos de los fármacos , Disfunción Ventricular Izquierda/tratamiento farmacológico , Función Ventricular Izquierda/efectos de los fármacos , Adulto , Anciano , Electrocardiografía/efectos de los fármacos , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Resultado del Tratamiento , Disfunción Ventricular Izquierda/diagnóstico
15.
Am J Med ; 104(1): 69-77, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9528722

RESUMEN

Patients with ischemic heart disease and significant left ventricular dysfunction are often difficult to manage medically. Revascularization procedures may improve left ventricular function and prognosis in this population if hypocontractile yet viable myocardium (hibernating myocardium) is demonstrated. Nuclear cardiology studies (single photon and positron methods), two-dimensional echocardiography, and magnetic resonance imaging studies have been utilized to identify hibernating myocardium. If thallium-201 studies are performed, the use of reinjection of thallium and repeat imaging improves the sensitivity of these studies for the detection of viable myocardium. Dobutamine echocardiographic studies may have a higher specificity and positive predictive value for the subsequent improvement of regional systolic left ventricular function after revascularization than the nuclear techniques. However, thallium studies have an excellent negative predictive value. Positron emission tomography (PET) allows the simultaneous assessment of perfusion and metabolic activity; however, these studies are expensive and not widely available. Functional evaluation with PET is in its infancy. Functional cardiac magnetic resonance imaging (MRI), although not widely available yet, provides the most accurate evaluation of regional ventricular function. MRI spectroscopy may be utilized to assess myocardial viability. As acquisition times improve and "real-time" imaging becomes a reality, MRI and MRI spectroscopy will likely become very accurate tools for assessing functional reserve and metabolic activity. The selection of the most appropriate method for assessment of myocardial viability will include consideration of a patient's characteristics, the presence of coronary arterial tree amenable to revascularization techniques, the techniques available to the clinician to assess viability, and local revascularization experience in this population. The result of an individual patient's evaluation is relevant to the consideration of coronary revascularization, or if this is not possible, cardiac transplantation.


Asunto(s)
Isquemia Miocárdica/complicaciones , Aturdimiento Miocárdico/diagnóstico , Aturdimiento Miocárdico/etiología , Ecocardiografía/métodos , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada de Emisión/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Disfunción Ventricular Izquierda/complicaciones
16.
Am J Ophthalmol ; 124(1): 117-9, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9222249

RESUMEN

PURPOSE: To report a child with leukocoria caused by occult penetrating trauma. METHODS: Case report. The clinical findings and surgical repair of acquired leukocoria of the right eye in a 2-year-old boy are presented. RESULTS: In the right eye, slit-lamp examination disclosed a retrolenticular cyclitic membrane and moderately severe (3+) cells and flare anterior chamber reaction. The eye was hypotonous, and B scan showed that the membrane was associated with a retinal detachment. Surgery was performed to repair the retinal detachment and to remove the retrolenticular membrane. Two months before initial examination, the patient had been attacked by a rooster. CONCLUSION: Occult penetrating trauma should be considered in the differential diagnosis of pediatric leukocoria.


Asunto(s)
Mordeduras y Picaduras/complicaciones , Pollos , Cuerpo Ciliar/lesiones , Lesiones Oculares Penetrantes/etiología , Cristalino/lesiones , Retina/lesiones , Desprendimiento de Retina/etiología , Animales , Cámara Anterior/patología , Extracción de Catarata , Preescolar , Cuerpo Ciliar/patología , Lesiones Oculares Penetrantes/diagnóstico , Lesiones Oculares Penetrantes/cirugía , Humanos , Cristalino/patología , Masculino , Retina/patología , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía
17.
Magn Reson Med ; 37(5): 754-63, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9126950

RESUMEN

A current limitation of many myocardial tag acquisitions employing SPAMM encoding is the relatively rapid loss of tag contrast over the cardiac cycle. Acquisition schemes that apply line tags produce prolonged tag contrast compared with directly excited grid tags. However, a grid-tag series can be generated by combining two orthogonal line-tag series. To be time efficient, each line-tag series can be acquired with the read gradient oriented perpendicular to the line-tag direction. There are several disadvantages associated with this approach, including the requirement to avoid signal fold-over and that fat shift artifacts appear in different directions in each line-tag series. Presented here is a method of applying separate line tags that does not require interchanging the read and phase encoding gradients and does not extend the scan time compared with a conventional grid-tag acquisition. Additionally, the means of generating grid tags results in a doubling of the tag contrast to noise ratio compared a line-tag set. Computer simulations are presented along with phantom and volunteer scans.


Asunto(s)
Corazón/fisiología , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Humanos
18.
Magn Reson Med ; 37(3): 410-7, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9055232

RESUMEN

A variety of variable and constant rate, sparse sampling strategies have previously been proposed to rapidly image dynamically changing objects. The majority of these strategies compile a k-space data set for any given time point by substituting k-space data from the most recently sampled time positions (extracted from the sparsely sampled set). The BRISK technique, is a variable rate, sparse sampling technique which additionally incorporates an interpolation scheme to more accurately represent k-space data at positions which were not directly sampled. Here, strategies are introduced that allow tubo concepts to be incorporated with BRISK. Simulations are conducted to compare the efficacy of the turbo BRISK acquisition and processing strategy against a constant rate, sparse sampling strategy with direct substitution of the most recently acquired k-space lines. It is shown that turbo BRISK generates images of similar quality in approximately half the time as the uniform sampling rate, sparse sampling strategy. Data from turbo BRISK acquisitions of multicardiac phase image sets, obtained on a normal volunteer and cardiac patients are presented.


Asunto(s)
Corazón/fisiología , Imagen por Resonancia Magnética/métodos , Frecuencia Cardíaca , Humanos
19.
J Am Coll Cardiol ; 29(1): 49-54, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8996294

RESUMEN

OBJECTIVES: We tested the hypothesis that angiotensin-converting enzyme (ACE) inhibitor therapy decreases left ventricular (LV) mass in patients with a left ventricular ejection fraction (LVEF) > 40% and no evidence of heart failure after their first acute Q wave myocardial infarction (MI). BACKGROUND: Recently, ACE inhibitor therapy has been shown to have an early mortality benefit in unselected patients with acute MI, including patients without heart failure and a LVEF > 35%. However, the effects on LV mass and volume in this patient population have not been studied. METHODS: Thirty-five patients with a LVEF > 40% after their first acute Q wave MI were randomized to titrated oral ramipril (n = 20) or conventional therapy (control, n = 15). Magnetic resonance imaging (MRI) performed an average of 7 days and 3 months after MI provided LV volumes and mass from summated serial short-axis slices. RESULTS: Left ventricular end-diastolic volume index did not change in ramipril-treated patients (62 +/- 16 [SD] to 66 +/- 17 ml/m2) or in control patients (62 +/- 16 to 68 +/- 17 ml/m2), and stroke volume index increased significantly in both groups. However, LV mass index decreased in ramipril-treated patients (82 +/- 18 to 73 +/- 19 g/m2, p = 0.0002) but not in the control patients (77 +/- 15 to 79 +/- 23 g/m2). Systolic arterial pressure did not change in either group at 3-month follow-up. CONCLUSIONS: In patients with a LVEF > 40% after acute MI, ramipril decreased LV mass, and blood pressure and LV function were unchanged after 3 months of therapy. Whether the decrease in mass represents a sustained effect that is associated with a decrease in morbid events requires further investigation.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Infarto del Miocardio/tratamiento farmacológico , Ramipril/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Femenino , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Hipertrofia Ventricular Izquierda/terapia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Volumen Sistólico/efectos de los fármacos
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