Hepatocellular carcinoma metastatic to the orbit.
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Orbital metastases of hepatocellular carcinoma are rare. The authors report a case of hepatocellular carcinoma metastatic to the orbit. A 56-year-old woman with hepatitis B infection as confirmed serologic test for hepatitis B surface antigen (HBsAg) demonstrated superior displacement of the left eyeball. The clinical appearance of the patient demonstrated an inferior displacement of the right eye. MRI disclosed an orbital mass that extended toward the lower eyelid and into the temporal fossa with destruction of the lateral orbital wall. Upon subsequent abdominal computed tomographic scans, the primary tumor was found in the liver. A biopsy specimen of the orbit showed trabecular structures with eosinophilic cytoplasm. Bile canaliculi and sinusoids were also seen. The tumor cells showed vesicular nuclei with mitoses. Immunohistochemical markers such as high-molecular-weight keratin and alpha-fetoprotein showed a positive response. However, immunohistochemical markers such as low-molecular-weight keratin and polyclonal carcinoembryonic antigen showed as negative. We diagnosed the tumor as a hepatocellular carcinoma metastatic to the orbit. A review of the pertinent literature disclosed relatively few occurrences of hepatocellular carcinoma metastasizing to the orbit. (+info)
Lid swelling and diplopia as presenting features of orbital sarcoid.
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Sarcoid is an idiopathic multisystem non-caseating granulomatous disease with protean clinical manifestations. In the eye, the common sites of involvement are the skin of eyelid, conjunctiva, uveal tract, retina, optic nerve and lacrimal gland. (+info)
Intracranial complications of transorbital stab wounds.
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Oscular and orbital injuries due to stab wounds may mask underlying serious intracranial damage. The correct clinical assessment and treatment of such cases require the attention of a team comprising a neurosurgeon, ophthalmologist, otolaryngologist, and plastic surgeon. (+info)
A critical evaluation of the pitchfork analysis.
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The pitchfork analysis has gained increasing acceptance among researchers and clinicians to evaluate the effects of orthodontic treatment that can be measured on lateral cephalometric radiographs. It is primarily used in Class II cases to distinguish between the skeletal and dental effects of such treatments. The aim of this study was to conduct an objective evaluation of the pitchfork analysis by comparing cephalometric data obtained by that method with those using the more conventional and established method of Bjork. The pitchfork analysis consistently provided an overestimation of the skeletal effects and an under-estimation of the dental changes. These results indicate that the pitchfork analysis is not sufficiently sensitive to distinguish between the skeletal and dental effects of orthodontic treatment. (+info)
Neurokinetics of lidocaine in the infraorbital nerve of the rat in vivo: Relation to sensory block.
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The kinetics of neural uptake and efflux of lidocaine hydrochloride were studies by means of a standardized technique for blocking the intraorbital nerve of the rat, using a palatal jig. Following injection of 14-C-labeled local anesthetic, groups of ten animals were saccraficed at incipient recovery from sensory block or at othertimes. The nerves were weighed and assayed for radioactivity. The lengths of nerve containing high levels of lidocaine varied inversely with the times elapsed since onset of block. In experiments where a fixed quantity (2 mg) drug was injected, the incidence of block 2 hours later was concentrated-dependent, occuring in 80 per cent of animals after 2 per cent, in 40 per cent after 1 per cent, and in none after 0.5 per cent lidocaine. Epinephrine, 1:200,000, prolonged by 80 per cent the block effected with 0.2 ml of 1 per cent lidocaine. At the onset of recovery the neural contents of lidocaine at the sites of injection were 484 plus or minus 404 ng/mg of nerve in epinephrine-treated nerves, and 274 plus or minus 218 ng/mg in nonepinephrine-treated nerved (N.S., P greater than 0.05). Quantitative comparisons of in-vivo effectiveness of local anesthetic solutions can be made with this technique. (+info)
Major orbital complications of endoscopic sinus surgery.
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BACKGROUND: The paranasal sinuses are intimately related to the orbit and consequently sinus disease or surgery may cause severe orbital complications. Complications are rare but can result in serious morbidity, the most devastating of which is severe visual loss. METHODS: A retrospective review was undertaken of four cases of severe orbital trauma during endoscopic sinus surgery. RESULTS: All the cases suffered medial rectus damage, one had additional injury to the inferior rectus and oblique, and two patients were blinded as a result of direct damage to the optic nerve or its blood supply. CONCLUSION: Some ophthalmic complications of endoscopic sinus surgery are highlighted, the mechanisms responsible are discussed, and recommendations for prevention, early recognition, and management are proposed. (+info)
Tumefactive fibroinflammatory lesion of the neck with progressive invasion of the meninges, skull base, orbit, and brain.
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SUMMARY: Tumefactive fibroinflammatory lesions of the head and neck are rare. CNS involvement has not been reported. We present a histologically proven case of a tumefactive fibroinflammatory lesion that originated in the left side of the neck and progressed over 2 years to involve the meninges, the cavernous sinuses, the right temporal lobe, and the right orbit. The lesion caused destruction of the skull base and a subdural hematoma. The relationship of the present lesion to idiopathic hypertrophic pachymeningitis and Tolosa-Hunt syndrome is discussed. (+info)
Integrating orbitofrontal cortex into prefrontal theory: common processing themes across species and subdivisions.
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Currently, many theories highlight either representational memory or rule representation as the hallmark of prefrontal function. Neurophysiological findings in the primate dorsolateral prefrontal cortex indicate that both features may characterize prefrontal processing. Neurons in the dorsolateral prefrontal cortex encode information in working memory, and this information is represented when relevant to the rules governing performance in a task. In this review, we discuss recent reports of encoding in primate and rat orbitofrontal regions indicating that these features also characterize activity in the orbitofrontal subdivision of the prefrontal cortex. These data indicate that (1) neural activity in the orbitofrontal cortex links the current incentive value of reinforcers to cues, rather than representing the physical features of cues or associated reinforcers; (2) this incentive-based information is represented in the orbitofrontal cortex when it is relevant to the rules guiding performance in a task; and (3) incentive information is also represented in the orbitofrontal cortex in working memory during delays when neither the cues nor reinforcers are present. Therefore, although the orbitofrontal cortex appears to be uniquely specialized to process incentive or motivational information, it may be integrated into a more global framework of prefrontal function characterized by representational encoding of performance-relevant information. (+info)