Diagnosis Of Ciliary Block Glaucoma Made By Pentacam: A Case Report

Ciliary block glaucoma is also known as the term malignantglaucoma,which was first proposed by Von Graefe,a German physician,in1896.It is a secondary angle closure glaucoma ofmulti-factor,multi-mechanism.With or without abnormal ocular anatomicalstructures,those factors or mechanisms participated in the process of ciliaryblock and aqueous misdirection,so that aqueous humor accumulated in thevitreous and the lens-iris diaphragm was pushed forward. Numerous clinicalentities share all or some of the following findings:(1)shallowing of anteriorchamber(central and periphery);(2)increased or normal intraocularpressure(IOP);(3) no effect or worsening following miotic therapy;(4)improvement with mydriatic-cycloplegic therapy;(5)response to specialvitreous surgery;(6) absence of pupillary block.At early stage of the process,aconverse effect with miotic therapy could be seen in suffered eyes,which is themore shallow anterior chamber and higher IOP.However,the higher IOP couldnot be obvious because of the combination of the variety of anti-glaucomadrugs.If we could monitor the change of anterior chamber depth closely aftertreatment of miotic,then there mey be an early diagnosis,which could result inan early treatment of this disease.The Oculus-Pentacam three-dimensional anterior chamber analyzer wasproduced by the German company Oculus.It is the world's first instrument touse a rotating Scheimflug camera, configured with two integratedcameras.One is located centrally, monitoring the condition of pupil, fixingposition,monitoring and correcting for eye movement and reports on thequality of each measurement.The another one locates on the rotatingwheel,which can take images of the anterior segment by rotating.Within2seconds,it can take50images from0o to180o,each of which will have500ture elevation points.By editing,there will be25000true elevation points of everytangential and sagittal(axial) curvature.In that case,a true360othree-dimensional structural image of the anterior segment will present.Thisinstrument has the characters of multi-angle, three-dimensionalvisualization,animation of the anterior segment and a coulorful pictureshowing the measurements of various parameters of cornea,anterior chamberand lens.The Pentacam is mainly used in measurement of cornealthickness,measurement of corneal topography,analysis of cataract,anteriorsegment imaging and analysis of anterior chamber.When it is used in analysisanterior chamber,the parameters of anterior chamber angle,anterior chambervolume,anterior chamber depth, pupil diameter and so on will bemeasured.Copared with other instruments,the Pentacam is non-contact forpatients,and provides a high resolution picture which can be easy to interpretand measure.And the most important is three-dimension and animation.It hasan easy operation and good repeatability and can be accepted easily bypatients,so that is an advantage for an objective record of dynamic change ofthe anterior chamber.The Pentacam can provide clinical evidences for thescreening,diagnosis and assessment of treatment of angle-closure glaucoma.Purpose: Reporting a case in which the clinical diagnosis of ciliary blockglaucoma was made by the Pentacam,to study the particular clinicalmanifestation at the early stage of this disease and discuss the value of thePentacam for clinical diagnosis of ciliary block glaucoma.Method: A young female patient came for treatment with chief complaintof gas pains and blurry vision of both eyes,accompany with dizziness,nauseaand vomiting.Shallow anterior chamber and high IOP presented when shereceived routine anti-glaucoma treatment including miotic therapy.Result ofoptometry showed she was highly myopia,but whose axial length wasshort.Then ciliary block glaucoma was suspected.By analyzing past casespublished,we found some clinical feature of early stage.We used the Pentacamto measure the parameters of anterior chamber prior to and after instillation ofmiotic,and the results were analyzed. Result:Measurements of anterior chamber prior to instillation were:righteye,pupil diameter(PD)3.56mm,anterior chamber depth(ACD)3.38mm,anterior chamber volume(ACV)245mm3,anterior chamberangle(ACA)41.9°,and left eye,PD2.91mm,ACD3.51mm,ACV235mm3,ACA43.5°.After instillation,the results were:right eye,1.42mm,ACD2.39mm,ACV103mm3,ACA34.5°,and left eye,PD1.43mm,ACD2.29mm,ACV106mm3,ACA33.1°.As the effect of miotic instillation,parameters of anterior chamber changed obviously.ACD decresed0.99mm in right eye and1.22mm in left eye.ACV decreased132mm3rightand129mm3left.ACA decreased7.4o right and10.4o left.As the miotic wasdiscontinued,anterior chamber deepened and visual acuity improved.For the2-month follow up without mydriatic therapy,condition was stable,withoutrecurrence.Conclusion: The Pentacam,which can be used to record the dynamicchange of anterior chamber objectively and accurately,may be a good choicefor the early clinical diagnosis of suspected ciliary block glaucoma.