Differential diagnosis of anterior segment cysts by ultrasound biomicroscopy

BACKGROUND: To describe the ultrasound biomicroscopic (UBM) features of anterior segment cysts. DESIGN: A retrospective case series. PARTICIPANTS: One hundred eighteen eyes with anterior segment cysts examined by UBM at The New York Eye and Ear Infirmary between August 1992 and November 1997 were included in this study. INTERVENTION: The authors reviewed demographic and diagnostic data from the medical record including ocular and medical history, age, race, gender, and intraocular pressure. Ultrasound data concerning the type, number, position, and acoustic characteristics of cysts were recorded. The authors then correlated the written, clinical, and UBM characteristics. RESULTS: One hundred eyes (92.6%) had neuroepithelial cysts. Ninety (83.3%) of these had primary neuroepithelial cysts, 10 (9.3%) had cysts associated with uveitis, 7 (6.5%) had implantation cysts, and 1 (0.9%) had a cavitated ciliary body tumor. Neuroepithelial cysts typically were round or ovoid, thin-walled, and echolucent. Of the 90 eyes with primary neuroepithelial cysts, 56 (62.2%) had 3 or fewer cysts; multiple cysts (>3 per eye) were found in 34 eyes (37.8%). The multiple cysts occupied more than 180 degrees in 12 patients (13.3%). Primary neuroepithelial cysts were located at the iridociliary junction (74.2%), pars plicata (14.0%), pars plana (6.8%), and iris (5.0%). Implantation cysts (seven eyes) tended to have thicker walls and two contained a copious, echogenic material. CONCLUSION: The UBM results provide important information regarding location and extent of anterior segment cystic lesions. Ultrasound characteristics may help differentiate between neuroepithelial, implantation, and neoplastic cysts.     

Relationship between corneal thickness and measured intraocular pressure in a general ophthalmology clinic

OBJECTIVE: To assess whether central corneal thickness (CCT) is a confounding factor in the classification of patients attending for glaucoma assessment in a district general hospital. DESIGN: Cross-sectional study by a single observer. PARTICIPANTS: Patients attending a general ophthalmic clinic: 235 clinically normal eyes, 52 eyes with normal-tension glaucoma (NTG), 335 eyes with primary open-angle glaucoma (POAG), 12 eyes with pseudoexfoliative glaucoma (PXE), 42 eyes with chronic angle closure glaucoma (CACG), and 232 glaucoma suspect (GS) eyes. INTERVENTION: Central corneal thickness was measured using ultrasonic pachymetry. MAIN OUTCOME MEASURE: Correlation of CCT and diagnosis. RESULTS: Mean CCT was 553.9 microm (95% confidence intervals [CI] for the mean, 549.0-558.8 microm) in the clinically normal eyes, 550.1 microm (95% CI, 546.6-553.7 microm) in the POAG eyes, 514.0 microm (95% CI, 504.8-523.3 microm) in the NTG eyes, 530.7 microm (95% CI, 511.2-550.1 microm) in the PXE eyes, 559.9 microm (95% CI, 546.8-573.0 microm) in the CACG eyes, and 579.5 microm (95% CI, 574.8-584.1 microm) in the GS eyes. The differences of mean CCT between the groups were highly significant (P< 0.001 analysis of variance). Eighty-five percent of eyes with NTG and only 36% of eyes with POAG had a mean CCT of 540 microm or less. Thirteen percent of eyes with POAG and 42% of GS eyes had a mean CCT greater than 585 microm. CONCLUSIONS: The CCT measurement is desirable in patients attending for glaucoma assessment in a district general hospital to avoid misclassification resulting from the relationship between CCT and tonometric pressure. Central corneal thickness alone is not an accurate predictor for the clinical diagnosis in this group of eyes. However, many eyes diagnosed as having NTG have thin corneas, which would tend to lower the tonometrically recorded intraocular pressure (IOP), so the finding of a less-than-normal thickness cornea introduces some doubt as to the diagnosis of NTG. For the GS eyes, most eyes had thick corneas, which would tend to increase the tonometrically recorded IOP. Thus, GS eyes with modest elevation of IOP and a thick cornea may be at low risk of progressing to POAG. Thus, many patients with "high IOPs" and a thick CCT do not necessarily have high IOPs and may not need to be followed as GS eyes.     

Nonmechanical excimer laser penetrating keratoplasty for perforated or predescemetal corneal ulcers

OBJECTIVE: To review the authors' results using nonmechanical excimer laser trephination in penetrating keratoplasty for perforated or predescemetal corneal ulcers. DESIGN: Noncomparative, consecutive, interventional case series. PARTICIPANTS: Thirty-two patients with perforated (17) or deep (15) corneal ulcers (9 bacterial, 5 acanthamoebal, 10 herpetic, 3 associated with rheumatoid arthritis, 5 other) necessitating immediate tectonic keratoplasty. INTERVENTION: Penetrating tectonic keratoplasty with excimer laser trephination was performed along metal aperture masks in donor and recipient corneas. MAIN OUTCOME MEASURES: Clinical results including intraoperative and postoperative complications were evaluated. RESULTS: Trephination was possible in all eyes without perforation of predescemetal ulcers or extrusion of intraocular contents. No eyes with bacterial or acanthamoebal ulcers showed persistence or recurrence of infection. One eye showed recurrent epithelial herpetic keratitis. Best-corrected postoperative visual acuity ranged from 20/700 to 20/20 (median, 20/58), with 30 of 32 eyes achieving improvement of best visual acuity during follow-up (mean, 22.4 months) and with 12 of 32 eyes reaching a visual acuity of 20/40 or greater. Eyes with bacterial or acanthamoebal ulcers showed best results. Episodes of graft rejection occurred in nine eyes and resulted in irreversible opacity of the graft in seven cases. None of the eyes lost all vision, developed endophthalmitis, or had to be enucleated. CONCLUSIONS: Nonmechanical trephination is a useful technical refinement of tectonic penetrating keratoplasty à chaud for perforated or deep progressive corneal ulcers. This technique greatly facilitates exact trephination under these difficult surgical conditions and might possibly improve the prognosis of this procedure.     

Diabetic retinopathy in a black population: the Barbados Eye Study.

OBJECTIVE: The distribution of diabetic retinopathy in black populations is largely unknown. The authors present retinopathy data from the predominately black participants of the Barbados Eye Study (BES). DESIGN AND PARTICIPANTS: Prevalence study of 4631 participants based on a random sample of the Barbados population 40 to 84 years of age (84% participation). MAIN OUTCOME MEASURES: Diabetes was defined as self-reported history of physician-diagnosed diabetes or glycosylated hemoglobin greater than 10% (>2 standard deviations above the population mean of persons without a diabetes history). Retinopathy was assessed by independent gradings of 30 degrees color stereo fundus photographs of the disc and macula. RESULTS: Diabetes was present in 19.4% of black (n = 4314), 15.2% of mixed (black and white; n = 184), and 7.5% of white/other (n = 133) self-reported racial groups. In the black/mixed population, regardless of diabetes status, the prevalence of retinopathy was 5.9%. In the 636 black and mixed participants with diabetes, the prevalence of retinopathy was 28.5%: 19.8% had minimum changes, 7.7% had moderate changes, and 0.9% had severe retinopathy. Clinically significant macular edema (CSME) was found in 8.6% of those with diabetes. CONCLUSIONS: In the population of African origin, approximately 1 in 17 persons had retinopathy. Among those with diabetes, 28.5% had retinopathy and 8.6% had CSME. These results highlight the clinical and public health relevance of diabetic retinopathy in the black population.     

角膜异物分区分级和记录方法

目的探讨角膜异物分区、分级及记录方法。方法对５６０例角膜异物分区、分级研究,在此基础上提出一种较为适用的记录方法,并用此指导临床实践。结果角膜异物有其分布特点,区、级不同,治疗及愈后不同。用此记录方法指导临床实践准确方便,不会出现误治漏治。结论角膜异物分区、分级及记录方法在临床上科学实用,在法医学上亦有使用价值     

外伤角膜瘢痕无晶状体眼戴角膜接触镜后的角膜地形图改变

目的 探讨外伤性角膜瘢痕无晶状体眼戴硬性透气性接触镜前,后角膜表面的改变。方法 对戴该镜者１７眼及对照组（不戴镜）１２眼,在戴镜前后进行角膜地形图检测。结果 戴镜后平均８．４月,角膜散光减少（Ｐ〈０．０１）,角膜表面变得比较规则（Ｐ〈０．０５）,角膜表面的屈光度有变得相对比较平均的趋势。结论 戴硬性透气性角膜接触镜能使角膜瘢痕所致角膜散光减少,角膜表面变得较为规则。     

视觉电生理联合应用对眼外伤视觉功能的评价

联合使用视觉电生理检查法评估外伤眼的视功能。方法单纯眼外伤３０例按受伤程度分３组,健康对侧眼为对照组,比较各组ＶＥＰＰ１００波潜伏值,３０Ｈｚ红闪炮光ＥＲＧ的振幅和暗适应ＥＲＧａ、ｂ波振幅的平均值。结论联合应用视觉电生理检测法是评价眼外伤视功能的可靠依据。     

硫酸二甲酯眼损伤的临床表现及治疗

对我们所遇８例硫酸二甲酯眼部中毒的临床表现及治疗进行分析讨论。眼部中毒主要为酸性烧伤、角膜损害,常同时合并呼吸道症状,重者可合并肝肾损害。治疗以硷性溶液冲洗结膜囊及局部对症为主。     

大鼠实验性视网膜光损伤中的视细胞凋亡

目的 进一步探讨视网膜光损伤的发病机制。 方法 20只Wistar大鼠分为实验组、对照组,分别在光照后12,24,36小时摘除眼球,视网膜组织行HE染色和核苷酸末端转移酶介导的DUTP缺口翻译法(TdT-mediated dUTP nick end labelling method,TUNEL)标记凋亡细胞。 结果 光照后12小时,视杆细胞外节出现少量空泡变性;24小时后,外核层出现明显的细胞核破碎、浓染和DNA裂解;36小时后,视杆细胞内、外节溶解,外核层大量细胞核丢失。 结论 视细胞凋亡是大鼠实验性视网膜光损伤的重要机制之一。 (中华眼底病杂志, 1999, 15: 167-169)     

Vanishing Psammoma Bodies in the Anterior Pituitary of the Human Newborn: An Immunohistochemical and Histometric Study

Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities, the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification encountered in prolactin (PRL)-producing pituitary adenomas.