小眼球高度远视眼透明晶状体摘除联合后房型Piggyback人工晶状体植入

目的：探讨小眼球高度远视眼的透明晶状体摘除联合后房型Piggyback人工晶状体植入术的疗效及人工晶状体度数的计算方法。方法：1例双眼极短眼轴合并高度远视、慢性闭角型青光眼患者行透明晶状体摘除联合后房型二片 30.0D Piggyback人工晶状体植入,术前双眼行YAG激光虹膜周切,术后一周右眼眼压高,行小梁切除术。术后一周、一月和三月分别视力、屈光状态,眼压和前房深度。利用光路追迹法计算人工晶状体度数。结果：术后三月最佳矫正视力与术前一致,屈光状态等效球镜度右 2.75D、左 2.88D,前房深度右眼、左眼分别由术前1.87mm、1.93mm加深到术后3.02mm和3.20mm,眼压正常。结论：对小眼球合并高度远视、慢性闭角型青光眼行透明晶状体手术联合二片后房型IOL植入,不仅能较好地解决屈光问题,而且有利于控制青光眼的发作和发展。利用光路追迹法计算IOL度数的方法是可取。     

超声乳化联合IOL植入治疗晶状体溶解性青光眼的临床研究

目的:研究超声乳化联合人工晶状体植入治疗晶状体溶解性青光眼的治疗效果。方法:对32例32眼过熟期白内障继发晶状体溶解性青光眼患者,采用超声乳化联合人工晶状体植入给予治疗,对视力及眼压情况进行观察和研究。结果:术后随访0.5a,眼压均控制到正常范围内,视力有不同程度提高。结论:通过临床观察证明单纯超声乳化联合人工晶状体植入治疗晶状体溶解性青光眼安全有效,且手术切口小,组织损伤小,术后反应较轻,可有效控制眼压,恢复视功能。     

超声乳化白内障摘除治疗晶状体溶解性青光眼的临床效果

目的:探讨超声乳化白内障摘除治疗晶状体溶解性青光眼的效果。方法:对25例晶状体溶解性青光眼患者控制眼压后行白内障摘除联合人工晶状体囊袋内植入术,观察术中、术后并发症,术后视力及眼压。结果:所有患者手术顺利,后囊完整,术后视力恢复好,眼压得到控制。所有患者无明显术中、术后并发症的发生。结论:超声乳化白内障摘除治疗晶状体溶解性青光眼安全有效。     

闭角型青光眼早期合并白内障超声乳化吸出术的临床观察

目的　探讨晶状体超声乳化吸出术 ,对缩瞳剂可以控制眼压的闭角型青光眼的抗青光眼治疗作用。方法　对有青光眼病史需使用缩瞳剂控制眼压的白内障病人在了解房角、眼压等情况后行晶状体超声乳化吸出联合后房型人工晶状体植入术。结果　 16只眼用缩瞳剂 (其中有 2只眼需联合使用噻吗心安 )可以控制眼压的青光眼 ,行晶状体超声乳化吸出术后全部病人在不使用抗青光眼药物的情况下眼压正常。结论　晶状体超声乳化吸出术可以改变晶状体虹膜膈、前房及房角的解剖结构和关系 ,从而消除闭角型青光眼发生的某些解剖基础 ,达到根治闭角型青光眼的目的     

晶状体超声乳化人工晶状体植入治疗原发性闭角型青光眼

目的探讨晶状体超声乳化吸出联合后房人工晶状体植入术,治疗白内障合并原发性闭角型青光眼的疗效。方法本院收治白内障合并原发性闭角型青光眼37例(37眼),术前控制眼压,经视力、眼压、前房角镜和裂隙灯显微镜等检查后,均单独采用晶状体超声乳化吸出联合后房人工晶状体植入。结果术后随访6~18个月,视力较术前提高,视力>0.5者20眼,占54.05%,22例术后眼压<18mmHg,另5例用1种降眼压药物眼压控制在18mmHg以下。结论晶状体超声乳化后房人工晶状体植入可有效地治疗合并白内障的原发性闭角型青光眼。     

晶状体玻璃体切除联合青光眼减压阀治疗晶状体脱位继发性青光眼

目的 评价晶状体玻璃体切除术联合青光眼减压阀治疗晶状体脱位继发性青光眼的疗效.方法 回顾性分析32例(32眼)外伤性晶状体脱位合并继发性青光眼资料,手术方法采用标准玻璃体切除三通道切口,颞上方植入Ahmed减压阀,对术前、术后视力、眼压及并发症等情况进行分析.结果 术后6个月复诊,矫正视力提高者28眼,视力不变4眼;术前平均眼压为(39.58±15.84)mm Hg(1 mm Hg =0.133 kPa),术后3d平均眼压为(9.66±2.84)mm Hg,术后1周平均眼压为(11.50±3.41)mm Hg,术后1个月平均眼压为(13.36±2.42)mm Hg,术后6个月平均眼压为(15.80±3.80)mm Hg,均显著低于术前眼压.主要并发症有前房积血、滤过过强致浅前房、引流管阻塞及滤过泡瘢痕化等.结论 晶状体玻璃体切除联合青光眼减压阀治疗晶状体脱位继发性青光眼可以降低眼压,保护视功能,是治疗该类青光眼较好的术式.     

内窥镜睫状突光凝用于晶状体脱位继发青光眼

目的 探讨眼内窥镜下睫状突光凝对于挫伤性晶状体脱位继发青光眼联合手术的疗效。方法 对14例(14眼)晶状体脱位继发青光眼采取晶状体粉碎、超声乳化、晶状体切除或整体摘出，并联合玻璃体切除、内窥镜下睫状突光凝及人工晶状体经巩膜缝合固定术。术后观察视力、眼压及眼内组织反应等情况。结果 术前平均眼压52mmHg(1mmHg=0．133kPa)。术后1周平均眼压16mmHg。随诊平均5．9月，平均眼压19mmHg。术前视力≤0．1者11眼，术后视力≥0．3者11眼。未发现严重的手术并发症。结论 眼内窥镜下睫状突光凝，手术直观，定量准确，对周围组织损伤小，对于晶状体脱位继发青光眼有相当理想的手术疗效。     

三联手术治疗青光眼合并白内障

目的评价小梁切除、晶状体超声乳化人工晶状体植人手术治疗青光眼合并白内障的临床结果。方法回顾性分析小梁切除、晶状体超声乳化人工晶状体植入手术治疗青光眼合并白内障74例（111眼）。术后随访3月～3年。结果三联手术可获得良好的视力恢复与眼压控制。结论三联手术治疗青光眼合并白内障具有眼压控制率高、提高视力好、术后并发症少。     

后房型有晶状体眼散光型人工晶状体矫正高度复性近视散光的并发症观察

目的研究后房型有晶状体眼散光型人工晶状体（TICL）矫正高度近视散光的安全性。方法对27例（50只眼）高度近视散光患者行后房型有晶状体眼散光型人工晶状体植入术。术前近视-6.75～-23.0D,平均（-11.04±3.12）D。散光1.25～6.50D,平均（2.31±0.77）D。随访6～24个月,主要观察手术前后角膜内皮细胞计数、眼压、前房、人工晶状体柱镜轴位和自身晶状体等情况。结果术后12个月,TICL旋转大于30°者1只眼占2%,TICL重新调整轴位。7只眼眼压一过性升高,经降眼压治疗,1周内恢复正常。1例（2只眼）眼压持续升高。1例双眼眩光。未发现晶状体混浊、色素性青光眼病例。结论 TICL作为一种前沿性屈光手术,风险小,并发症少,安全可逆,是目前临床上非常理想的矫正散光的新方法 。     

超声乳化人工晶状体植入联合小梁切除术疗效观察

目的评价闭角型青光眼合并白内障行晶状体超声乳化人工晶状体植入联合小梁切除术的疗效。方法对36例(48眼)青光眼合并白内障施行晶状体超声乳化人工晶状体植入联合隧道内小梁切除术,观察术后视力、眼压、房角、眼底改变及视野变化。随访时间为术后1~6月。结果术后视力、房角均较术前改善,视野检查未发现进一步损害。术后眼压全部降至正常范围,平均眼压(16.02±2.14)mmHg。术后有一过性浅前房23眼。结论白内障晶状体超声乳化人工晶状体植入联合小梁切除术是治疗闭角型青光眼合并白内障的有效方法。     

Homeostasis of the retinal micro-environment: I. Magnesium,potassium and calcium distributions in the avian eye

The concentrations of Mg²⁺, K⁺ and Ca²⁺ in the intraocular fluids (IOFs) and blood plasma of chickens and pigeons were determined by atomic absorption spectrophotometry. The Mg²⁺ concentration in the IOFs of both species was greatest in the liquid vitreous adjacent to the retina followed by aqueous > blood plasma > plasma dialysate. In contrast the concentration of K⁺ in the IOFs of both chickens and pigeons was greater in the aqueous than in the liquid vitreous. The concentrations of Ca²⁺ in all IOF compartments of chicken eyes were virtually identical and were lower than that of blood plasma. The concentrations of Mg²⁺ in the IOFs of the chicken, especially in the liquid vitreous, was remarkably stable; experimentally lowering or raising the plasma Mg²⁺ concentration over a relatively wide range had little or no effect on the Mg²⁺ concentration in the IOFs of these animals. We can conclude that a high Mg²⁺ and low K⁺ concentration in the extracellular fluids of the retina is maintained in the avian eye, as in the mammalian eye, by active transport processes across the blood-retinal barrier systems. Because the avian retina is completely avascular, the site of these homeostatic transport processes must be the epithelium of the retinal choroid and/or the pecten. These findings support the concept that the contribution of the vitreous to the homeostasis of the retinal micro-environment is inversely related in vertebrates to the degree of retinal vascularization.     

Vergleich der Durchmesserreaktion retinaler Arterien und Venen auf Flickerlicht

ZusammenfassungZiel In dieser Studie soll die durch Flickerlicht verursachte Durchmesserreaktion retinaler Arterien und Venen hinsichtlich Ausmaß und zeitlichem Ablauf verglichen werden.Methoden In die klinische Studie wurden 26 gesunde Probanden einbezogen. Der Durchmesser der retinalen Gefäße jeweils eines Auges wurde kontinuierlich mittels eines Retinal vessel analyzer gemessen. Jede Untersuchung bestand aus 100 s Baseline sowie 5 Perioden von 20 s Flickerlichtstimulation, gefolgt von 80 s Beobachtung.Ergebnisse Unmittelbar nach Flickerlicht dilatierten die Arterien um 6,9±2,8% (MW±STD) und die Venen um 6,5±2,8% (Unterschied nicht signifikant). Der Quotient aus arterieller und venöser Dilatation (AVDQ) betrug 1,25±0,69 (Spannweite 0,2 bis 2,8). Es konnte keine signifikante Altersabhängigkeit der arteriellen bzw. venösen Dilatation oder des AVDQ nachgewiesen werden. Die arterielle Dilatation ging nach 25,9±10,8 s in eine leichte Konstriktion von –2,7±1,4% über. Im Gegensatz dazu waren die Venen zum Zeitpunkt des individuellen Konstriktionsmaximums noch um 0,5±1,3% dilatiert (p<0,001).Schlussfolgerungen Die flickerlichtinduzierte Durchmesserreaktion retinaler Arterien und Venen unterscheidet sich bei Gesunden nicht in ihrem mittleren dilatativen Maximum, aber in Form und zeitlichem Verlauf des Abklingens der Dilatation.Unterstützung durch: BMBF 13N7999.Vortrag gehalten auf der 101. Jahrestagung der DOG, Berlin, September 2003.     

Acute Multifocal Placoid Pigment Epitheliopathy Associated with Cavernous Sinus Thrombosis

Acute multifocal placoid pigment epitheliopathy (AMPPE) has been associated with disease of the central nervous system. In this case report, we discuss a patient presenting with AMPPE in the setting of a new central nervous system association: cavernous sinus thrombosis.     

Dual nonlinearities regulate contrast sensitivity in pattern discrimination tasks

Many current psychophysical models propose that visual processing in cortex is hierarchical, with nonlinearities sandwiched between linear stages of processing. In earlier publications, we proposed a model of this type to account for masking effects found with spatial frequency and orientation discriminations. Our model includes two nonlinear mechanisms that regulate contrast sensitivity in early cortical mechanisms. The first is a local within-pathway nonlinearity that accelerates at low contrasts but is compressive at high. The second is a pooled nonlinear gain control process that operates over a broad range of neurons with different tuning characteristics. Here, we test predictions of the model for spatial frequency discriminations. The model predicts that at low contrasts, adding a grating mask oriented parallel to test gratings will improve discrimination performance via operation of the within-pathway nonlinearity, analogous to the "dipper effect" found with contrast discriminations. Adding an orthogonally oriented mask is predicted to have no effect at low contrasts, where pooled gain control processes contribute little to performance. At high contrasts, the model predicts that performance will asymptote and become independent of contrast with either parallel or orthogonal masks. The results confirm model predictions.