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A patient with keratoconus suffered two traumatic ruptures of her corneal graft wound, both of which were successfully repaired with restoration of graft clarity. There were also two apparently unrelated episodes of rejection. The endothelium was monitored by specular microscopy during this period. Our findings suggest that the insult to a transplanted cornea from an episode of rejection may be greater than that from traumatic wound rupture.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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All patients presenting with neurological problems to an eye hospital casualty department over one year were prospectively studied. A total of 119 patients were identified. The most frequent diagnoses were retrobulbar neuritis (34; 28.5%), sixth cranial nerve palsy (22; 18.5%), third cranial nerve palsy (15; 12.6%) and Adie's tonic pupil (11; 9%). Cranial nerve palsies were most commonly due to diabetes or hypertension (16; 43.2%). Only one intracranial aneurysm was found. Symptoms included blurred vision (52; 43.7%), binocular diplopia (51; 42.8%), and eye pain (27; 22.7%). Fifty patients (42.0%) were referred by a general medical practitioner. Twenty-two (18.5%) were admitted to hospital. Forty-nine skull X-rays were requested and all were normal. Twenty-nine chest X-rays were requested. One (3.4%) showed an abnormality (carcinoma of the bronchus). Neurological patients present to ophthalmic casualty departments because of ophthalmic symptoms. Ophthalmic casualty officers are able to make working diagnoses and to direct patients appropriately. The use of investigations in the casualty department, however, is unlikely to be productive.  相似文献   
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Goei  R; Baeten  C; Arends  JW 《Radiology》1988,168(2):303-306
Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis.  相似文献   
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