Blanqueamiento ocular quirúrgico. Cosmética versus seguridad / Surgical eye whitening. Cosmesis versus safety

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La opacificación capsular posterior: un factor a tener en cuenta en la valoración del nervio óptico / Posterior capsular opacification: One factor to be considered for the study of the optic nerve

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Coroideremia: seguimiento durante un año con polarimetría láser / Choroideremia: one-year follow-up with scanning laser polarimetry examination

Caso clínico: Presentamos el seguimiento de un caso de coroideremia que fue sometido a tres campos visuales automatizados blanco-blanco y tres polarimetrías láser (PL) con GDx VCC en el transcurso de un año. Se encontró un deterioro perimétrico en índices y escotomas. En concordancia, los parámetros de retardo de la capa de fibras nerviosas de la retina y los mapas cambiaron en un análisis serial avanzado con GDx VCC en los dos ojos. Discusión: El análisis con GDx VCC puede ser un método objetivo y cuantitativo para evaluar la progresión de las distrofias coriorretinianas como la coroideremia

Case report: We report the follow-up of a case of choroideremia who underwent three white-on-white automated visual field and three scanning laser polarimetry (SLP) examinations by means of a GDx VCC in the course of one year. A bilateral perimetric deterioration in indices and scotomas was found. As a result, retinal nerve fiber layer retardation parameters and maps changed on GDx VCC advanced serial analyses in both eyes. Discussion: Serial analyses with GDx VCC may be used as objective and quantitative tests to assess the progression of chorioretinal dystrophies like choroideremia (Arch Soc Esp Oftalmol 2008; 83: 487-492)

[Choroideremia: one-year follow-up with scanning laser polarimetry examination]. / Coroideremia: seguimiento durante un año con polarimetría láser.

CASE REPORT: We report the follow-up of a case of choroideremia who underwent three white-on-white automated visual field and three scanning laser polarimetry (SLP) examinations by means of a GDx VCC in the course of one year. A bilateral perimetric deterioration in indices and scotomas was found. As a result, retinal nerve fiber layer retardation parameters and maps changed on GDx VCC advanced serial analyses in both eyes. DISCUSSION: Serial analyses with GDx VCC may be used as objective and quantitative tests to assess the progression of chorioretinal dystrophies like choroideremia

Severe orbitopalpebral emphysema after nose blowing requiring emergency decompression.

PURPOSE: Orbital emphysema is a frequent condition associated with medial wall fractures after blunt trauma. It is usually a benign, self-limited phenomenon. The authors are unaware of previous reports of severe orbital emphysema needing emergency decompression with no evidence of any previous significant trauma such as the case presented herein. METHODS/RESULTS: A 51-year-old woman had painful swelling of the left orbital region that prevented her from opening her eyelids. She complained of a coincident cold with abundant mucous rhinorrhea. She had blown her nose vigorously several times. A computed tomography scan revealed a left proptosis, an extensive orbitopalpebral emphysema, and a blowout fracture of the medial wall of the left orbit. A complete ophthalmic examination was only possible after a needle decompression. No significant ocular damage was observed, so outpatient treatment was provided. Twenty-eight hours later, the swelling had almost disappeared, and the ocular assessment was normal. CONCLUSIONS: A forceful expiratory effort raising intranasal pressure may cause a medial wall orbital fracture. If the airway hyperpressure episodes are repeated, a severe orbitopalpebral emphysema may develop. Should there be any suspicion of vascular compression, it must be drained to allow the assessment of visual function and theoretically prevent a potentially irreversible ischemic visual loss.

Effect of posterior capsular opacification removal on automated perimetry.

PURPOSE: Although posterior capsular opacification (PCO) is a common phenomenon in a considerable number of ophthalmologic patients, no prospective controlled trials assessing its influence on automated perimetry exist. This technique continues as a standard in the diagnosis of glaucoma and neuro-ophthalmological diseases. The aim of the present report is to investigate the effect of PCO on automated visual field examination. METHODS: A total of 26 PCO affected eyes of 26 patients had Humphrey SITA standard (program 24-2) immediately before, and between 1 and 8 weeks after Neodymium : YAG capsulotomy. The effect of learning associated with repeated testing was controlled with automated perimetry before enrollment and visual fields of the fellow eye. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), and global perimetric pre- and post-laser indices were compared using the Student's t-test for paired samples. Correlation and linear regression analyses were also performed. RESULTS: BCVA and mean deviation (MD) improved following capsulotomy. Pattern standard deviation (PSD), an indicator of localized defects in the field, also improved significantly when PCO was solved. Moreover, a strong association among BCVA, MD, and PSD was shown both prior to and after capsulotomy. CONCLUSION: PCO is a heterogeneous mean opacity. This polymorphism may alter visual field results, and may even simulate the perimetric behaviour of other pathologies such as glaucoma. Consequently, the presence of PCO should be considered in the interpretation of any automated perimetry in pseudophakic patients. In addition, the values obtained before capsulotomy may partially predict the values obtained after capsulotomy.

Life-span development of odor identification, learning, and olfactory sensitivity.

In the first of three studies, children (aged 8 to 14 years) were found to perform worse than young and middle-aged adults in unprompted identification of doors, with average performance much like that of elderly adults. Comparisons on other tasks, specifically odor threshold, prompted odor identification, and object naming (Boston Naming Test), across the life span (five groups) revealed that children have the same excellent olfactory sensitivity as young adults and merely lack odor-specific knowledge that accumulates slowly through life. Such knowledge apparently accumulates so slowly that age-associated discriminative losses, measurable by early middle age, begin to wear away gains obtained through experience before odors can become overlearned. In the second study, a novel adaptive psychophysical method, the step procedure, confirmed the equivalent sensitivity of children and young adults. In the third study, a paired-associate task illustrated the sluggish course of odor learning. Young adults outperformed children, though the youngest group, first graders, made up ground relatively fast. For children and adults, common odors facilitated performance relative to novel odors. The outcome highlighted the relevance of semantic factors in odor learning irrespective of age.

Perception of sweetness and bitterness in different vehicles.

In the present study, we investigated taste-taste, taste-vehicle, and simultaneous taste-vehicle-taste mixtures. Subjects made estimates of the sweetness and bitterness of 27 stimuli. Sucrose (292, 585, and 1170 mM), caffeine (13, 26, and 52 mM), and binary mixtures of low (292-13 mM), middle (585-26 mM), and high (1170-52 mM) levels of both components were dispersed in water, carboxymethylcellulose (CMC) 1% w/v, and gelatin 6% w/v. The sweetness and bitterness of the sucrose-vehicle-caffeine combinations were significantly weaker than the respective sucrose-vehicle and caffeine-vehicle combinations. The emerged mutual suppressive effects were asymmetrical and persisted when both tastants were presented in CMC and gelatin. Moreover, the increase in vehicle consistency and the simultaneous addition of another taste reduced the perceived intensity of a taste either presented alone or dissolved in water. For both sweetness and bitterness, the total taste suppression observed was always significant.

Relationships between ingestion and gustatory perception of caffeine.

We observed that taste detection thresholds for caffeine (CAF) are elevated in habitual CAF users relative to nonusers. A series of experiments were carried out to explore that relationship and assess the influences of salivary CAF and acute vs. chronic CAF ingestion. A significant correlation between CAF ingestion and taste threshold was noted in two studies of U.S. adults, although this was not observed in a parallel study involving an Argentinean population. Acute CAF ingestion (5.5 mg/kg) had no appreciable effect on taste thresholds. Threshold values greatly exceeded even peak salivary CAF levels, indicating that classical taste adaptation was an unlikely influence. Chronic CAF ingestion (450 mg/day for 3 weeks) also had no consistent effect on taste thresholds for CAF or other taste stimuli. Although a number of explanations are considered, we suggest that the sensory phenomenon may reflect preexisting differences between CAF users and nonusers or perhaps an effect of exposure to other bitter and/or CAF-containing foods and beverages.

Interactions between CO2 oral pungency and taste.

Two experiments are reported in which the perceptual interactions between oral pungency, evoked by CO2, and the taste of each of four tastants--sucrose (sweet), quinine sulfate (bitter), sodium chloride (salty), and tartaric acid (sour)--were explored. In experiment 1 the effect of three concentrations of each tastant on the stimulus-response function for perceived oral pungency, in terms of both rate of change (slope) and relative position along the perceived pungency axis, was determined. In experiment 2 the effect of three concentrations of CO2 on the stimulus-response function for the perceived taste intensity of each tastant was examined. Results show that the characteristics of the mutual effects of tastant and pungent stimulus depend on the particular tastant employed. Sucrose sweetness and CO2 oral pungency have no mutual effect; sodium chloride saltiness or tartaric acid sourness and CO2 oral pungency show mutual enhancement; and quinine sulfate bitterness abates CO2 oral pungency, whereas CO2 has a double and opposite effect on quinine sulfate bitterness--at low concentrations of bitter tastant CO2 enhances bitterness, and at high concentrations of bitter tastant CO2 abates bitterness. It is suggested that the perceptual attributes of saltiness and sourness are closer, from a qualitative point of view, to oral pungency than are the attributes of bitterness and sweetness.

Bilateral integration in the common chemical sense.

Human participants judged the pungency of various concentrations of carbon dioxide presented to one nostril, the other nostril, or both (dichorhinic stimulation). Perceived magnitude grew sharply with concentration over the range explored. The combinatorial rule of bilateral integration followed the Pythagorean theorem: the effective mass in a bilateral stimulus equalled the square root of the sum of squares of the mass entering each nostril. This simple rule implies a possible mutual inhibitory interaction between the two nostrils, but it also implies partial spatial summation of the sensory impact of bilaterally presented concentrations. When persons inhale a relatively strong irritant, such as the higher concentrations used here, they will exhibit a very brief reflex interruption of inhalation. An experiment on the threshold for the reflex implied that it too followed the Pythagorean rule of integration. This occurred for both males and females, though females displayed a lower threshold for the reflex, whether evoked unilaterally or bilaterally. This reflex may hold promise as an objective indicator of functional status of the nasal common chemical sense.

Electrical activity of the olfactory bulb. Changes induced by lesions of contralateral olfactory areas.

Control values for a) trains of sinusoidal waves, b) slow potentials and c) basal activity, were determined in rabbits whose olfactory bulbs (O.B.'s) had been implanted with chronic electrodes. One olfactory epithelium was destroyed in one group of animals and the activity of the contralateral O.B. was analyzed for 7 days. Then, the olfactory peduncle homolateral to the olfactory epithelium previously destroyed was sectioned and the bulbar activity recorded for 15 days. In another group of animals, the olfactory peduncle was sectioned and the activity of the contralateral O.B. analyzed similarly to the previous group. It was observed that no changes occurred in the contralateral O.B. after the destruction of the receptors. The sectioning of the olfactory peduncle produced a temporary increase in the amplitude and duration of the trains of sinusoidal waves from the contralateral O.B. and, only in few cases, in the amplitude of the slow potentials. These results were related to the various nervous structures that had been damaged during the operations.

Electrical activity of the olfactory bulb. Changes induced by lesions of contralateral olfactory areas

Control values for a) trains of sinusoidal waves, b) slow potentials and c) basal activity, were determined in rabbits whose olfactory bulbs (O.B.’s) had been implanted with chronic electrodes. One olfactory epithelium was destroyed in one group of animals and the activity of the contralateral O.B. was analyzed for 7 days. Then, the olfactory peduncle homolateral to the olfactory epithelium previously destroyed was sectioned and the bulbar activity recorded for 15 days. In another group of animals, the olfactory peduncle was sectioned and the activity of the contralateral O.B. analyzed similarly to the previous group. It was observed that no changes occurred in the contralateral O.B. after the destruction of the receptors. The sectioning of the olfactory peduncle produced a temporary increase in the amplitude and duration of the trains of sinusoidal waves from the contralateral O.B. and, only in few cases, in the amplitude of the slow potentials. These results were related to the various nervous structures that had been damaged during the operations.

Electrical activity of the olfactory bulb. Changes induced by lesions of contralateral olfactory areas.

Control values for a) trains of sinusoidal waves, b) slow potentials and c) basal activity, were determined in rabbits whose olfactory bulbs (O.B.s) had been implanted with chronic electrodes. One olfactory epithelium was destroyed in one group of animals and the activity of the contralateral O.B. was analyzed for 7 days. Then, the olfactory peduncle homolateral to the olfactory epithelium previously destroyed was sectioned and the bulbar activity recorded for 15 days. In another group of animals, the olfactory peduncle was sectioned and the activity of the contralateral O.B. analyzed similarly to the previous group. It was observed that no changes occurred in the contralateral O.B. after the destruction of the receptors. The sectioning of the olfactory peduncle produced a temporary increase in the amplitude and duration of the trains of sinusoidal waves from the contralateral O.B. and, only in few cases, in the amplitude of the slow potentials. These results were related to the various nervous structures that had been damaged during the operations.