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Biomedical subjects

G Ravalico

Publications and source records attributed to G Ravalico.

71 records · Page 4Linked to original sources
PubMed1979

Correlations between cutaneous and retinal microaneurysms in diabetes mellitus (preliminary note).

A group of diabetic patients was submitted to a capillaroscopic examination at the level of the peri-ungual vallum and to a fluoroangiographic examination of the retina, for the evaluation of possible correlations between vessel conditions in to various districts. The Authors remarked that the subjects affected by proliferative diabetic retinopathy presented a greater dilatation of the ansae at cutaneous level, with haemorrhagic extravasations in 70% of the cases. On the contrary, on the subjects with nonproliferative diabetic retinopathy numerous aneurysmal "buttons" were noted at cutaneous level, both apically and laterally along the vascular ansa.

Adolescent↗
PubMed1978

Retinal angiography in the study of cerebral ischemia.

On the basis of the assumption of an affinity between cerebral and retinal vessels, it was sought to demonstrate that the variations induced in the retinal circulation are akin to those occurring at the cerebral level. The technique of retinal fluorescein angiography was used to evaluate the amplitude of the vasal lumen and the speed of circulation. In 5 patients, the drug used was (-)eburnamonine. While the calibre of the retinal arterioles did not undergo variations, a shortening of the mean transit time was observed in 3 of the 5 cases treated, evidencing an improvement in blood flow.

Brain Ischemia↗
PubMedDate not supplied

Oscillatory potentials of the electroretinogram in hypertensive patients with different antihypertensive treatment.

Oscillatory potentials of the electroretinogram are useful to confirm the diagnosis of essential hypertension. Thirty-five hypertensive patients underwent primary antihypertensive therapy with four different treatments. Oscillatory potentials were recorded before the treatment and after 12 months. The oscillatory response increased in a statistically significant manner in the angiotensin-converting enzyme inhibitor group. This is probably caused by the vasodilatation mechanism, which increases the retinal blood flow.

Action Potentials↗
PubMedDate not supplied

Capsulorhexis size and posterior capsule opacification.

PURPOSE: Posterior capsule opacification (PCO) after intraocular lens (IOL) implantation has a multifactored pathogenesis. Capsulorhexis and capsular bag implantation of a one-piece, biconvex poly(methyl methacrylate) (PMMA) IOL are likely to reduce the PCO incidence. This study was performed to determine whether an ideal capsulorhexis size able to reduce PCO incidence exists. METHODS: A retrospective study of 107 patients who had extracapsular cataract extraction with capsulorhexis and capsular bag IOL implantation was carried out. The PCO site (central, paracentral, and peripheral) and degree (mild, moderate, and severe) were evaluated in relation to the capsulorhexis edge location relative to the IOL optic. Slitlamp biomicroscopy and photography and examination with a three-mirror Goldmann lens were performed. Patients were divided into three groups. Group 1: capsulorhexis free edge located on the IOL optic for 360 degrees; Group 2: capsulorhexis free edge located asymmetrically on and peripherally to the IOL optic; Group 3: capsulorhexis free edge located peripherally to IOL optic for 360 degrees. Each group was divided into two subgroups; one received polyHema IOLs and the second, PMMA IOLs. RESULTS: In Groups 1 and 2, the capsular transparency was higher than in Group 3 (P < .04). Central opacification percentage was lower in Group 1 than in Groups 2 and 3 (P < .04). No statistically significant differences between the polyHema and the PMMA subgroups were seen. CONCLUSIONS: Capsulorhexis with a slightly smaller diameter than the IOL optic appears to be better than a large-size capsulorhexis in reducing the incidence of PCO.

Aged↗
PubMedDate not supplied

Occult choroidal neovascularization in adult-onset foveomacular vitelliform dystrophy.

AIMS: To report 6 cases in which indocyanine green angiography (ICGA) failed to convert occult choroidal neovascularization (CNV) into well-defined CNV in adult-onset foveomacular vitelliform dystrophy (AOFVD). METHODS: Patients with AOFVD observed from 1993 to 1999 were prospectively followed up. Whenever the development of CNV was suspected, ICGA was performed to detect the precise location and extension of CNV by means of the IMAGEnet System. RESULTS: Six out of 51 patients (11.7%) developed CNV during the follow-up. The CNV was of the occult type, with an associated detachment of the pigment epithelium in 1 eye. On ICGA, a large hyperfluorescent lesion appeared after about 10 min, irregularly increasing with time, without a clear visualization of site and extension of CNV. CONCLUSIONS: In AOFVD, ICGA may fail to convert occult CNV into well-defined CNV, which is amenable to laser treatment, since hyperfluorescence caused by the probably vitelliform material binding to the ICG molecule and the CNV-induced hyperfluorescence cannot be angiographically distinguished from each other.

Aged↗
PubMedDate not supplied

Vascularized pigment epithelial detachment in adult-onset foveomacular vitelliform dystrophy.

PURPOSE: To report a case showing adult-onset foveomacular vitelliform dystrophy (AOFVD), associated with vascularized pigment epithelial detachment. CASE REPORT: A 72-year-old female affected by AOFVD complained with blurred vision and metamorphopsia in her right eye, seven months after a routinary clinical examination. Visual acuity in right eye dropped from 0.6 to 0.3, and biomicroscopic fundus examination revealed a serous pigment epithelial detachment arising from the temporal margin of the pseudovitelliform lesion. Fluorescein angiography showed an uneven filling of the pigment epithelial detachment, suggesting the presence of a subfoveal choroidal neovascularisation, which was confirmed by indocyanine green angiography. DISCUSSION: The association between AOFVD and vascularized pigment epithelial detachment, supports the hypothesis that AOFVD may be a different subgroup of age-related macular degeneration with specific genetic predisposition.

Age of Onset↗
PubMedDate not supplied

Subretinal fluid ferning test in rhegmatogenous retinal detachment.

PURPOSE: The ferning test involves a process of crystallization achieved simply by removing water and is feasible for all ocular fluids. The ferning test of subretinal fluid (SRF) from patients with rhegmatogenous retinal detachment (RRD) reveals three different patterns: type 1 showing thin crystals, type 2 with larger crystals and type 3 with small, curvilinear structures with no tree-like appearance. The present study was designed to determine whether the SRF ferning test is correlated with the clinical features and the surgical outcome of RRD. METHODS: A series of 65 consecutive patients with RRD at the first onset were considered. Particular attention was paid to duration, extension, and surgical outcome of RRD. SRF samples were collected during scleral buckling surgery. The fluid was dropped onto the slide of a light microscope, left to dry, and examined under the microscope. RESULTS: There was a significant difference between SRF ferning types 1 and 2 as regards, duration and extension (both p < 0.001). There was also a significant difference between SRF ferning types 2 and 3 as regards duration (p<0.001), extension (p<0.001), and surgical outcome (p<0.05). CONCLUSIONS: The ferning test of SRF is quick and simple and can be regarded as a useful tool for obtaining information about clinical features, such as duration or extension of first, onset in uncomplicated cases of RRD especially for purposes of forensic medicine.

Body Fluids↗
PubMedDate not supplied

Electro-oculographic abnormality in eyes with uveal melanoma.

PURPOSE: To seek out correlations between preoperative electro-oculogram (EOG) recordings with different types of uveal melanomas, after surgery. METHODS: We analysed the EOG recordings of 120 patients with uveal melanomas, histologically verified, 100 in the choroid and 20 in the iris and ciliary body. The EOG data were correlated with the site, size and histological type of the tumor. RESULTS: In 100 eyes with choroidal melanoma the Arden Index (AI) was less than in fellow eyes (mean 126.6, SD +/- 23.8 and 202.9, SD +/- 47.0; p=0.01). The EOG values were not different with respect to the histological type, site and size of tumor. In cases with iris and ciliary body melanomas the AI were not significantly different from the fellow eyes (mean 180.6, SD +/- 23.6 and 203.2, SD +/- 38.7; p=0.07). CONCLUSIONS: Since the EOG is abnormal in eyes with choroidal melanoma, it can be considered a powerful auxiliary for diagnosing these tumors.

Adult↗
PubMedDate not supplied

Comparing measurements of retinal nerve fiber layer thickness obtained on scanning laser polarimetry with fixed and variable corneal compensator.

PURPOSE: To compare retinal nerve fiber layer (RNFL) thickness measurements obtained on scanning laser polarimetry (SLP) with commercially available instruments coupled with fixed (FCC) and variable corneal compensator (VCC). METHODS: Forty-two eyes of 42 patients underwent a complete ophthalmologic evaluation and achromatic automated perimetry (24-2 program, SITA standard strategy). Nineteen eyes were healthy (average mean deviation: -0.12 dB +/- 2.26) and 23 glaucomatous (average mean deviation: -4.92 dB +/- 6.49). All patients underwent SLP with both FCC and VCC. Adequate compensation of corneal birefringence on FCC-SLP was checked acquiring macular retardation map (MRM). RNFL thickness was evaluated considering superior and inferior maximum (SM, IM), average thickness and ellipse average (AT, EA), and superior and inferior average (SA, IA). Mean values (+/-SD) for each parameter measured by the two polarimeters were compared and linear regression calculated. The ability of each parameter to discriminate between normal and glaucomatous eyes was evaluated on both polarimeters calculating area under ROC curve. RESULTS: A significant linear correlation for all parameters was noted (r range: 0.65-0.78). VCC produced slightly higher thickness values than FCC, both in normal and glaucomatous eyes. On both polarimeters, area under ROC curve for all parameters discriminated adequately healthy from glaucomatous eyes (range: 0.68-0.81). CONCLUSIONS: In a highly comparable and selected group of normal and glaucomatous eyes, FCC-SLP and VCC-SLP showed considerable concordance in measuring peripapillary RNFL thickness, both for sectorial and global parameters. Proper corneal birefringence compensation provided separation of normal from glaucomatous eyes on both polarimeters.

Adult↗
PubMedDate not supplied

Macular edema and visual loss after macular pucker surgery with ICG-assisted internal limiting membrane peeling.

PURPOSE: To describe the occurrence of massive macular edema and visual loss after indocyanine green-assisted (ICG) macular pucker surgery. METHODS/RESULTS: A 74 years old female presented with a macular pucker and a hypertrophy of the retinal pigment epithelium (RPE) in her left eye. The preoperative visual acuity (VA) was 20/100. Surgery consisted of cataract extraction, lens implantation and standard pars plana vitrectomy with peeling of epiretinal tissue followed by the removal of the internal limiting membrane (ILM) remnants stained using a 0.05% ICG solution. One day after surgery, VA was counting fingers. There was an extensive macular edema and retinal thickening with hyperfluorescence during fluorescein angiography and pronounced autofluorescence using ICG filters. During follow up, the macular edema resolved completely, but VA decreased to 20/800 at six months postoperatively. There was a central scotoma and unstable fixation seen during microperimetry. DISCUSSION: This case report indicates that ICG might come into contact with bare retina if injected following removal of epiretinal membranes. Whether the observed RPE hypertrophy might have contributed to the pathogenesis of the adverse effect described remains hypothetical.

Aged↗
PubMedDate not supplied

Intraocular lens decentration and posterior capsule opacification: anatomo-pathologic findings after implantation of AMOSI40 IOLS.

PURPOSE: To evaluate the incidence of intraocular lens (IOL) decentration and posterior capsule opacification (PCO) after implantation of a three-piece posterior chamber silicone IOL in a series of eyes examined postmortem. METHODS: Twenty-three pseudophakic enucleated human cadaver eyes, implanted with AMO SI40NB IOLs after phacoemulsification, were analyzed. Eyes obtained postmortem were sectioned at the equatorial plane and the anterior segment photographed from a posterior view. Location of IOL optic and haptics, type of fixation, and centration of IOL was evaluated. PCO was graded and the presence of Nd:YAG laser posterior capsulotomy was noted. RESULTS: Mean age at the time of surgery was 77.83 years, mean time since implantation was 18.26 months. In all the eyes examined, IOL haptics were positioned in the capsular bag. Mean decentration was 0.20+/-0.16 mm. No correlation was found between IOL decentration and time since implantation. The degree of peripheral PCO ranged from none (13.0%) to mild (39.1%) to moderate (26.1%) to severe (21.7%). The degree of central PCO ranged from none (52.2%) to mild (30.4%) to moderate (4.3%). Three patients (13.0%) underwent Nd:YAG laser posterior capsulotomy. CONCLUSIONS: A very good centration can be obtained when silicone AMOSI40NB IOLs are correctly implanted with the haptics inside the capsular bag. About half of the implants showed no central PCO while Nd:YAG laser posterior capsulotomy rates documented a relatively low PCO 18 months after surgery. A careful in the bag haptics placement is needed in order to reduce the IOL decentration and to prevent central PCO.

Aged↗
PubMedDate not supplied

Homonymous bilateral hemianopsia: electrophysiological study of a case.

Described is a case of bilateral homonymous hemianopsia with macular sparing, resulting from head trauma. The case presented lesions of the occipital visual areas which involved entirely the left hemisphere and only partially the right hemisphere. VEP were obtainable only from electrodes placed on the right hemisphere with both right eye and left eye stimulation. VEP mapping showed that each eye projects macular fibres towards functional areas of the right occipital hemisphere. Electrophysiological examination confirmed objectively and for the first time in man the theory of "double cortical macular representation". Clinical implications of this finding are discussed.

Child↗
PubMedDate not supplied

Iris fluorescein angiography and iris indocyanine green videoangiography in pseudoexfoliation syndrome.

BACKGROUND: Precise evaluation of the iris vascular pattern in pseudoexfoliation syndrome (PXS) may be difficult with iris fluorescein angiography (IFA) because of the frequent presence of a heavily pigmented iris and conspicuous late leakage. However, iris indocyanine green videoangiography (IICGV) can precisely visualize details of the iris vascular pattern. This study analyzed the utility of IICGV in detecting microvascular changes in PXS and compared these findings with those of IFA. METHODS: Twenty-eight patients with PXS in both eyes underwent an ophthalmic examination including IFA and IICGV. IICGV was done with the IMAGEnet system H1024. RESULTS: IICGV gave better visualization of iris hypoperfusion and anastomotic vessels whereas iris microneovascularisation was far more clearly visible on IFA. IICGV also detected iris pigment epithelium defects. CONCLUSIONS: IICGV can be considered a useful tool for evaluation of the iris vascular pattern in PXS. Iris hypoperfusion did not appear to contribute to the development of iris microvascular changes.

Aged↗