Cataract surgery is now often referred to as refractive surgery.It has come into the focus in recent years to choose the intraocular lens of appropriate power so as to achieve the expected postoperative refraction.Two main factors influence the measurement of intraocular lens power(IOL),the IOL power calculation formula and biological measurement of the ocular.The achievement of expected surgical outcome depends on the selection of the IOL power calculation formula and biological measurement instrument that suit the intraocular lens the specific patient.The article presents an overview of IOL power calculation with a focus on the above two aspects.

Keratoconus is a relatively common, bilateral, non-inflammatory corneal ectasia characterized by thinning and scarring of the central portion of the cornea,seriously destroyed the vision. The aetiology of this condition is probably multiple factors,such as collagen themry,genetic themry,epithelia themry,etc.Now,recent investigations devote to gene,and think it one of the major aetiological factors. Laboratory studies suggest a role for degradative enzymes and proteinase inhibitors and a possible role for the interleukin-1 system in its pathogenesis, but these roles need to be more clearly defined. It has well-described clinical signs, but early forms of the disease may go undetected unless the anterior corneal topography is studied. Contact lenses are the most common treatment modality. When contact lenses fail, corneal transplant is the best and most successful surgical option.

Retinal neovascularization is a phenomenon observed in various kinds of eye diseases and it can threaten the visual function of patients. Medical treatment to inhibit retinal neovascularization will give them effective help. This article reviewed animal models of retinal neovascularization and researching development of medicine in this field.

corrected visual acuity and good visual quality are clinic effects standard of laser in situ keratomeleusis.Visual quality descending for patients after LASIK surgery depends on many factors.This review recommends analyses the influence of visual quality for patients after LASIK surgery and it's guiding significance to LASIK from seven sides,such as visual acuity,refactive diopter,contrast sensitivity,wavefront aberration,increment of Q-value,binocular visual function,the change of dominant eye.

Recent studies of immunology have aroused new interest in regulatory T cell for immune responses,and scientists have recognized that suppressor T cells exist in vivo and regulatory T(Treg) cells play a crucial role in mediating immune tolerance and preventing autoimmune diseases.This article reviews the types,characteristics,mechanisms,and roles of Treg in immune tolerance,aiming to offer some important theoretical evidence for the treatment of allograft rejection and autoimmune diseases.

Expanded understanding of the ocular surface and tear film interaction contributes to the pathophysiology of dry eye.Maintenance of tear film requires an intricate nervous and hormonal regulation.The changes in tear film,neurogenic inflammation and sex hormone are key factors in dry eye pathogenesis.

According to the anatomic classification,refractive surgery is divided into keratorefractive surgery,phakic refractive surgery and scleral refractive surgery.Most procedures for the correction of ametropia are performed on the cornea,with laser-assisted in situ keratomileusis(LASIK) being the most common one.LASIK has shown its limitations,however.For the correction of higher myopic and hyperopic refractive error,the procedure has considerable undesired effects,such as loss of contrast,glare,and iatrogenic keratectasia.Therefore,a variety of intraocular lens,known as phakic refractive surgery,have been designed to achieve full correction of high myopia and hyperopia without loss of accommodation.Phakic refractive surgery is different from kerato-or scleral refractive surgery in that it involves phakic intraocular lens,non-phakic intraocular lens and clear lens extraction +introcular lens.The author will outline recent progress in phakic intraocular lens and provide unifying concepts that are accepted by ophthalmologists.

The technique of amniotic membrane transplantation is developping rapidly in treating ocular surface disease recently. Amniotic membrane is widely used in this area due to its unique structure, procurment and graft puparation. The authors describe the methods of processing and preservation of human amniotic membrane, and the histological study and clinical application experiences as well.

0.05).The iris diaphragm was flat to mild concave which lead the width of anterior chamber angle increased postoperation, no peripheral synechia was found. Conclusion: Phacoemulsification and foldable posterior chamber intraocular lens implantation through clear corneal incision had no significant influence on the long term intraocular pressure in simple senile cataract patients, the width of anterior chamber angle increased postoperation.

With the development of modern vitrectomy,some new ideas have been proposed concerning the treatment of Terson syndrome.Developed neurosurgery has offered more chances of survival to patients with subarachnoid hemorrhage(SAH).Terson syndrome,as the initial presentation,has gained more and more attention from ophthalmologists,though strict guidelines for its treatment have not yet been established.The paper reviews the progress in the clinical researches of Terson syndrome.