Analysis of aqueous humor obtained from normal eyes of llamas and alpacas.

OBJECTIVE: To evaluate composition of aqueous humor obtained from normal eyes of llamas (Lama glama) and alpacas (Lama pacos). SAMPLE POPULATION: Aqueous humor obtained from 10 male llamas and 10 male alpacas. PROCEDURE: All animals had normal eyes, as determined by ocular examination. Aqueous humor samples were obtained via paracentesis of the anterior chamber of animals that were heavily sedated. Chemical analysis included measurement of concentrations of sodium, potassium, magnesium, chloride, bicarbonate, phosphorus, and glucose as well as osmolality and pH. RESULTS: With the exception of potassium concentrations, values for aqueous humor composition did not differ significantly between llamas and alpacas. Mean +/- SD values for llamas and alpacas, respectively, were: sodium, 154.7 +/- 2.1 and 152.7 +/- 2.1 mEq/L; potassium, 5.3 +/- 0.4 and 4.6 +/- 0.4 mEq/L; magnesium, 1.8 +/- 0.1 and 1.7 +/- 0.1 mg/dl; chloride, 130.0 +/- 1.6 and 127.0 +/- 3.3 mEq/L; bicarbonate, 19.2 +/- 1.5 and 20.2 +/- 2.3 mEq/L; phosphorous, 2.7 +/- 0.3 and 2.5 +/- 0.4 mg/dl; glucose, 80.3 +/- 3.9 and 80.8 +/- 7.3 mg/dl; total protein, 29.0 +/- 8.6 and 31.5 +/- 10.1 mg/dl; and osmolality, 305.8 +/- 11.8 and 306.2 +/- 4.9 mOsm. The pH ranged from 7.5 to 8.0 for both species. Potassium concentrations were significantly higher in llamas than alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Except for potassium, composition of aqueous humor did not differ significantly between llamas and alpacas. Aqueous humor composition of llamas and alpacas is similar to that of other species that have been examined.

Intraocular pressure in normal llamas (Lama glama) and alpacas (Lama pacos).

OBJECTIVE: To determine the mean intraocular pressure in llamas (Lama glama) and alpacas (Lama pacos) using applanation tonometry.Animals studied: Ten llamas and 10 alpacas.Procedures: Intraocular pressure (IOP) was measured with a Tono-Pentrade mark XL (Mentor Ophthalmics, Inc., Norwell, MA, USA). Three values, with 5% variance, were recorded for each eye. Least-squares means were determined for IOP for each eye of llamas and alpacas. Controlling for age, differences between left and right eye were analyzed using ANOVA. Two age groups were established, less than 5 years and greater than 5 years. The effect of age on IOP within each group was analyzed by linear regression. Probability values of less than 0.05 were considered significant. RESULTS: Comparison of mean IOP between right (n = 20) and left eyes (n = 20), independent of species type, showed no differences in IOPs for llamas and alpacas. Mean IOP declined with increasing age in llamas and alpacas. Mean IOPs for 20 eyes in 10 llamas was 16.96 +/- 3.51 mmHg. Mean IOP for 20 eyes in 10 alpacas was 16.14 +/- 3.74 mmHg. Mean IOP for all eyes (n = 40), independent of species, was 16.55 +/- 3.55 mmHg. The range of IOP in normal llamas and alpacas within 2 SD (95% of the population) was 14.89+/-18.21 mmHg. CONCLUSIONS: There was no significant difference in IOP between alpacas and llamas. Mean IOP in both species decreased with increased age.

[Wilson's disease. X-ray CT and MRI aspects of the brain in a case before treatment]. / Maladie de Wilson. Aspects TDM et IRM de l'encéphale d'un cas avant traitement.

Wilson disease is an autosomal recessive disorder of copper metabolism. The case of a young girl is reported here, with CT and MRI data before any treatment. The unusual MR presentation on T2 weighted sequences is studied, and compared with those described in patients under treatment.

[Lobar holoprosencephaly associated with heterotopic gray matter. A case disclosed in adulthood by epilepsy]. / Holoprosencéphalie lobaire associée à des hétérotopies de substance grise. Un cas révélé à l'âge adulte par une épilepsie.

A case of lobar holoprosencephaly associated with heterotopias of the grey matter is reported. The patient was a young woman whose cerebral malformation was revealed by epileptic seizures at the age of 22. There was no intellectual deficit. Computerized tomography and, chiefly, magnetic resonance imaging, enabled the study of the malformation.

[Role of imaging in the diagnosis of coma]. / Place de l'imagerie dans le diagnostic des comas.

Imaging has become one of the main methods to diagnose and monitor coma. CT is the technique of choice in the exploration of traumatic coma or spontaneous intracerebral haemorrhage, but MRI is better than CT to explore comas of ischaemic, infective, tumoral or toxic origin, as it provides earlier and more precise images.

Separation of diffusion and perfusion in intravoxel incoherent motion MR imaging.

Intravoxel incoherent motion (IVIM) imaging is a method the authors developed to visualize microscopic motions of water. In biologic tissues, these motions include molecular diffusion and microcirculation of blood in the capillary network. IVIM images are quantified by an apparent diffusion coefficient (ADC), which integrates the effects of both diffusion and perfusion. The aim of this work was to demonstrate how much perfusion contributes to the ADC and to present a method for obtaining separate images of diffusion and perfusion. Images were obtained at 0.5 T with high-resolution multisection sequences and without the use of contrast material. Results in a phantom made of resin microspheres demonstrated the ability of the method to separately evaluate diffusion and perfusion. The method was then applied in patients with brain and bone tumors and brain ischemia. Clinical results showed significant promise of the method for tissue characterization by perfusion patterns and for functional studies in the evaluation of the microcirculation in physiologic and pathologic conditions, as, for instance, in brain ischemia.

[Magnetic resonance imaging of the head compared with the CT scan]. / IRM de la tête comparée avec le CT scan.

After the description of the normal head anatomy in MRI and its exploration plans, the images observed in benign and malignant tumours of the brain, in cerebral ischaemic attacks, in the diseases of the orbit, face and skull base, are considered. The limits and present indications of the technique are defined.

Comparison of sonography and computed tomography in the study of orbital space-occupying lesions.

Seventy cases of space-occupying lesions in the eyeball and 140 extraocular masses in the orbit were explored by both sonography and compute tomography (CT). The merits of each method were demonstrated relative to defining the location, extension, and nature of the lesion. In adults with ocular masses, sonography is usually sufficient. For retinoblastoma, CT is usually necessary to rule out an extraocular extension. When an orbital process is involved, greater diagnostic accuracy can be achieved if the two methods are combined.