Granulomatous orbital lesions: computed tomographic features.

Orbital lesions exhibiting granulomatous inflammation represent a heterogeneous group of diseases characterized by infiltration with epithelioid cells. The authors retrospectively reviewed the orbital computed tomography (CT) scans of 39 patients who had biopsy-proven lesions with granulomatous inflammation and found that diagnosis on the basis of CT was possible in only a few patients, those with a lesion of characteristic location and attenuation (such as a dermoid cyst) or characteristic distribution (such as bilateral enlargement of the lacrimal gland occurring in orbital sarcoidosis). In patients with multicompartmental disease exhibiting bone and extraorbital involvement the site of origin of the mass, the pattern of bone involvement and the clinical findings helped in classifying the cause of the lesion as Wegener's granulomatosis, a foreign body or mucormycosis. CT was crucial in determining the intraorbital and extraorbital extent of the lesion before excision or biopsy.

Determination of paracetamol and its four major metabolites in mouse plasma by reversed-phase ion-pair high-performance liquid chromatography.

A reversed-phase ion-pair high-performance liquid chromatographic method has been used for the separation of paracetamol and its four major metabolites (glucuronide, sulphate, cysteine and mercapturate conjugates) in mouse plasma samples. An ODS column was used and the mobile phase consisted of an aqueous solution of 0.01 M tetrabutylammonium chloride and 0.01 M Tris buffered to pH 5.0 with phosphoric acid, with methanol as the organic solvent. The gradient elution started with 30% methanol. After a delay of 0.5 min the methanol concentration was increased linearly to 75% over 7.5 min. The column was returned to the initial conditions after a delay of 1 min. A methanol solution of theophylline was added to the mouse plasma sample, centrifuged and immediately injected into the chromatographic system. The advantages of this method include good and rapid separation (last metabolite detected at 6.86 min), well resolved peaks, only a small amount of sample required for assay, adequate precision (no coefficient of variation was greater than 10% for paracetamol metabolites) and a high sensitivity (particularly for unchanged paracetamol and the cysteine conjugate).

Orbital lesions with granulomatous inflammation.

Orbital lesions characterized by granulomatous inflammation are a heterogeneous group of diseases of various causes with a common histopathological substrate involving aggregates of epithelioid cells. Forty-one patients (27 females and 14 males) with biopsy-proven granulomatous inflammation were seen at an orbital clinic between 1978 and 1989. The mean age at presentation was 40.2 (extremes 6 and 77) years. Two main clinical presentations were noted: painless, subacute or chronic mass effect, and tender, subacute inflammatory process. Six patients had secondary features that were infiltrative in character. The lesions were primarily located in the anterior superior orbit. In nearly half the patients the granulomatous reaction was confined to the orbit (predominantly ruptured dermoid and localized orbital sarcoid), and the remainder had either regional involvement (Wegener's granulomatosis or fibro-osseous process) or systemic involvement (sarcoidosis).

Dominant macular colobomata.

Hereditary bilateral macular colobomata are not a consequence of an anomalous closure of the fetal fissure. Their extreme rarity, their lack of embryological explanation, and their morphologic similarity to postinflammatory congenital macular scars called the hereditary-malformative etiology of this entity in question. The authors describe a four generation family with seven affected members with isolated autosomal dominant bilateral macular colobomata.

Enfermedad de Hansen, córnea y anejos oculares

Examinamos 37 pacientes diagnosticados de lepra estudiando sus alteraciones en anejos y córnea. De ellos eran formas lepromatosas, 2 borderline lepromatosas, 2 borderline tuberculoide y 2 tuberculoides. La mayor parte se encontraban entre la 6ª y 7ª década. En 6 casos no encontramos lesiones de ningún tipo. En los restantes observamos una disminución de la agudeza visual directemante relacionada con la duración de la enfermedad. el hallazgo más frecuente fue la madarosis supraciliar, seguido de la falta parcial de pestañas y madarosis. Debilidad del orbicular y/o lagoftalmos encontramos en 6 casos. La opacidades debidas a queratopatías leprosas típicas, queratopatía "en banda", por oxposición pannus y lepromas corneales, fueron los hallazgos corneales más frecuentes. La presencia de neovascularización fue detectada en 5 pacientes. Concluimos destacando la importancia del estudio de la lepra en oftalmología.

Complex convolutions in neurons of the dorsal lateral geniculate nucleus of the normal albino rat.

The postnatal development of complex convolutions (CCs) of the dorsal lateral geniculate nucleus (LGNd) in normal rats has been studied quantitatively with light microscopy. We report that immature neurons do not contain these scarcely understood organelles, since they can be seen for the first time in very few, mature neurons of the 30 day rat; their number constantly increases during the following 4 months. These cytoplasmic inclusions can be equally seen in the aged rat. CCs are present in neurons of all sizes, except the smallest, which correspond to the interneuron population. Although, morphologically, CCs of the LGNd of the rat are similar, but not identical, to the cytoplasmic multilaminated bodies of the cat, intermediate forms are described.

A morphologic analysis of neurons and neuropil in the dorsal lateral geniculate nucleus of aged rats.

Light and electron microscopy were used to investigate the morphology of neuropil and neuronal cell bodies of the dorsal lateral geniculate nucleus (LGNd) of aged rats. Light microscopic examination reveals that, despite the optic tract showing signs of degeneration, the LGNd is scarcely affected. Thus, a slight but significant reduction in the diameters of both soma and nuclei is observed in aged neurons of the LGNd. Ultrastructural analysis demonstrates a few degenerating profiles of the neuropil. Neurons resembling relay cells exhibit typical features of aged neurons. Cells showing a very infolded nucleus, most of the ER cisternae connected with the nuclear envelope, abundant free polyribosomes and subsurface cisterns associated with mitochondria are similar to interneurons of adult rats. Therefore, aging and partial loss of visual input appear to induce small changes in the morphology of most of LGNd neurons.

Quantitative cellular changes during postnatal development of the rat dorsal lateral geniculate nucleus.

Quantitative changes in cell number during development of the dorsal lateral geniculate nucleus were determined using semithin serial sections of tissue obtained from 28 rats on postnatal day 0, 5, 8, 10, 20, 30, 90 or 165. Our results show three phases of postnatal development in the rat dorsal lateral geniculate nucleus: phase 1 from birth until eye opening, which occurs around the 12th day in these litters; phase 2 from eye opening through stabilization of neuron number on the 30th postnatal day, and phase 3 from that event until adulthood. During the first period increases in neuron number and in glial cell number are found accompanying a nearly seven-fold increase in dorsal lateral geniculate nucleus volume. Phase 2 includes a high incidence of neuronal cell death and a continuous increase in the number of glial cells. The third phase is characterized by a stabilization in the number of neurons, although the glial cell number continues to increase. Neuronal density decreases exponentially throughout the postnatal life of the rat, while the density of glial cells remains relatively stable over the period of study. The postnatal phenomenon of an initial increase in neuron number followed by a period of neuron death may be related to modulating and plastic functions which occur in the rat dorsal lateral geniculate nucleus before a stable neuronal population is achieved on the 30th postnatal day.

Stability of the neuronal population of the dorsal lateral geniculate nucleus (LGNd) of aged rats.

The variations, with aging, of both neuronal and glial populations of the rat LGNd have been studied quantitatively. Our results show a stability of the total number of neurons of the rat LGNd with aging; this, plus the constant increase of the rat LGNd volume throughout rat life, causes the neuronal density to decrease slowly. Our data prove the necessity of determining the total number of neurons, not just neuronal density, in order to find out the actual evolution of the neuronal population with aging. Both glial cell number and density show an increase throughout rat life.

Telangiectatic hamartoma of the iris and ciliary body.

Two cases of telangiectatic hamartoma of the iris and ciliary body are reported, one of them with its histopathological study. No previous cases have been found, as such, in the current literature. The most important descriptions of primary vascular lesions of the iris and ciliary body are briefly reviewed.