Biomedical subjects
Publications and source records attributed to B S Grimson.
The use of high-speed air-cooled rotary cutting instruments is common in dental practices. When used near open wounds, the forced air can lead to subcutaneous emphysema and involvement of vital structures. This case highlights the unfortunate episode of orbital emphysema with optic nerve damage after a pneumatically cooled drill was used in the removal of a mandibular second molar.
We studied the histopathologic changes in the brain and eye of a 5 1/2-month-old infant who suffered a profound hypotensive episode three days antemortem. Nuclear pyknosis and other histologic changes characteristic of ischemic cell necrosis were found throughout the brain and in the retina's photoreceptor-cell layer. These findings suggest that hypoxic ischemia may produce preferential damage to the photoreceptor-cell layer.
A patient with pituitary-sellar disproportion, a perichiasmal visual field defect, and no clinically demonstrable endocrinopathy is presented. Radiographic and pathologic studies suggested that the pituitary-sellar disproportion was secondary to sellar hypoplasia, a previously unrecognized cause of the chiasmal syndrome. It remains to be seen whether hormonal manipulation aimed at suppression of gonadotropin- and/or prolactin-secreting cells might obviate the need for exploration in patients similar to ours.
We compared magnetic resonance imaging of the optic nerves and chiasm with computed tomography in four patients (a 17-year-old girl, a 14-year-old boy, a 13-year-old girl, and a 22-year-old woman) with biopsy-proven or suspected optic gliomas. Orbital abnormalities were effectively viewed by both techniques. Gliomatous and normal optic nerves had similar spin-echo magnetic resonance imaging characteristics. Magnetic resonance was superior to contrast-enhanced computed tomography for identification of the intracranial optic nerves, chiasm, and optic tracts, but computed tomography delineated orbital anatomic and spatial relationships better.
Plastic casts of ocular vessels were made from postmortem specimens obtained from patients who had had hypertension and arteriosclerosis, diabetes mellitus, and retinopathy of childhood. In conjunction with scanning electron microscopy, the casts serve as models of pathologic vascular changes, including arteriovenous crossing defects, microaneurysm, localized capillary nonperfusion, and rapidly growing peripheral choroidal vessels. These preliminary findings should serve to encourage further study of ocular vascular abnormalities with the use of plastic casting techniques.
In serial experiments on cats, intravenous digital subtraction angiography (DSA) was utilized to observe orbital and ocular circulation. Images of the orbital arterial system as well as normal ocular vasculature were obtained, utilizing dosage of contrast material acceptable for human study. Images obtained after intra-arterial DSA had no advantage over those obtained with intravenous DSA. After retrobulbar injection of 3 ml of saline, intravenous DSA demonstrated straightening of the external ophthalmic arteries showing the potential of this method for identifying orbital vascular pathology.
In a 34-year-old black man with pulmonary tuberculosis, a rapidly enlarging choroidal tuberculoma progressed to larger size, despite appropriate systemic anti-tuberculous therapy. The eye harboring the tuberculoma became blind and painful, and was subsequently enucleated. Conventional staining of tissue sections revealed a choroidal granuloma without evidence of organisms, but tubercle bacilli were demonstrated by fluorescence microscopy.
The authors report what they believe to be the first case of a blepharoplasty procedure complicated by an acute postoperative dacryocystitis that precipitated orbital cellulitis. The patient had a preoperatively compromised nasolacrimal drainage system. Because acute dacryocystitis and resulting orbital cellulitis are potential postoperative complications of a blepharoplasty, blepharoplasty candidates should undergo preoperative evaluation of their nasolacrimal drainage systems.
Explore the source record for details and available documents.
Vascular casts of the human lamina cribrosa region were studied in three autopsy specimens utilizing scanning electron microscopy (S.E.M.) in own modified technique. The lamina cribrosa is supplied from two major sources, the short posterior ciliary artery within the sclera and the distal optic nerve sheath pial vasculature. Recurrent choroidal arteries supplied a small number of centripetal branches to the lamina cribrosa. The central retinal artery did not give off centrifugal branches as it coursed through the lamina. The findings in these three human cases in three-dimensional visualization support other recent studies using serial histologic sectioning techniques. The photomicrographs are presented as a first successful images in S.E.M. for additional appreciation of the topographic morphology of radial arterioles.
Two children, a 9-year-old girl and an 8-month-old girl, were first examined because of unilateral proptosis. Both children were found to have unilateral optic nerve glioma, accompanied in the second case by neurofibromatosis. Two years after Patient 1 was first examined, the initial findings of thin vertical retinal striae and a gray opacification of the peripapillary retina had resolved. The enlarged left optic disk had an average diameter of 2 mm while that of the normal right optic disk was 1.6 mm. The disk-arteriolar ratio was R.E.:16:1 and L.E.: 20:1. Four years later, the patient's visual acuity was still 20/20 in both eyes and the only visual field abnormality was an enlarged blind spot corresponding to the enlarged left optic nerve head. Fundus photographs, orbital echography, and computed tomography showed no change in the size or location of the optic nerve glioma during the six-year follow-up period. In Case 2, the initial intraocular pressure was higher in the proptotic right eye than in the left eye (25 vs 19 mm Hg), but subsequent intraocular pressures were within normal limits and approximately equal in the two eyes. The disk-arteriolar ratio was R.E.:21:1 and L.E.: 18:1 and the cup-disk ratio was R.E.: 0.7 and L.E.: 0.3. Computed tomography disclosed an enlarged right retrobulbar optic nerve, a superior orbital fissure that was much larger on the right than on the left, and a larger cavernous sinus on the right. The right sphenoid bone was partially absent. Despite mild developmental delay, the patient's visual acuity apparently remained normal and the ophthalmologic findings did not change significantly during the 18-month follow-up period.
Of 11 patients (eight women and three men, ranging in age from 16 to 48 years) who had sarcoidosis of the optic nerve that caused decreased visual acuity and visual field abnormalities, only two were known to have sarcoidosis at the time the visual impairment developed. Four patients had granulomas involving the optic nerve head, four had granulomatous inflammation of the orbital or intracranial optic nerve or chiasm, and three had retrobulbar neuritis. All 11 patients had histologically confirmed idiopathic noncaseating granulomatous inflammation and eight of the 11 had abnormalities compatible with sarcoidosis in chest roentgenograms. In the three patients in whom the serum level of angiotensin-converting enzyme was determined, it was increased in one and normal in the other two. Computed tomography of the anterior visual pathways was the single most useful neurodiagnostic study. Treatment with corticosteroids was beneficial in six of the 11 cases. These cases demonstrated that sarcoidosis should be included in the differential diagnosis of any inflammatory or compressive lesion involving the anterior visual pathways.
An excellent functional result was obtained after microsuture of a trochlear nerve which was inadvertently divided during the course of a craniotomy. Successful intracranial suture of this nerve has not previously been reported. Ophthalmoscopic detection of excyclotorsion of the eye on the side of the trochlear nerve palsy is discussed, along with its value in the differential diagnosis of acquired vertical diplopia.
The simultaneous presentation of unilateral proptosis and subcutaneous nodules on the upper chest, back, and thigh was observed in a 46-year-old woman with a previous history of ovarian carcinoma. Excisional biopsy of a subcutaneous nodule revealed metastatic adenocarcinoma similar to the primary ovarian tumor histopathology. This case is singular in its concomitant orbital and subcutaneous cancer metastases and provides rare support for ovarian carcinoma spreading to the orbit.
Transient retinal folding was observed in a 28-year-old woman presenting with bilateral uveal inflammation. These retinal striae resolved within 5 weeks as the anterior uveal inflammation responded to topical cycloplegic and corticosteroid therapy. Ultrasonographic findings demonstrated choroidal thickening as a contributing factor in the production of these temporary retinal folds. We present this unusual case since transient retinal folding has been rarely documented, and as far as we are aware, has not been previously investigated by ultrasonography.
Explore the source record for details and available documents.
The clinical course of six patients with isolated trochlear nerve palsy as the only ocular motor manifestation of herpes zoster ophthalmicus has been analyzed. Spontaneous recovery occurred in only three. Review of the literature does not clarify the mechanism of such palsies, which potentially may result from the following conditions: local orbital muscle inflammation and ischemia; contiguous intracavernous spread of inflammation from the trigeminal nerve; and a concurrent but independent motor neuropathy or ganglionitis.
Explore the source record for details and available documents.