资源描述
,Modifiez le style du titre,Modifiez les styles du texte du masque,Deuxime niveau,Troisime niveau,Quatrime niveau,Cinquime niveau,*,*,Modifiez le style du titre,Modifiez les styles du texte du masque,Deuxime niveau,Troisime niveau,Quatrime niveau,Cinquime niveau,*,*,Modifiez le style du titre,Modifiez les styles du texte du masque,Deuxime niveau,Troisime niveau,Quatrime niveau,Cinquime niveau,*,*,Modifiez le style du titre,Modifiez les styles du texte du masque,Deuxime niveau,Troisime niveau,Quatrime niveau,Cinquime niveau,*,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Kallmann综合征的MRI表现,Kallmann综合征的MRI表现,1,INTRODUCTION:,Kallmann syndrome is an inherited disorder characterized by hypogonadotrophic hypogonadism and anosmia or hyposmia.,KS is due to abnormal migration of gonado-tropin-releasing hormone (GnRH) as well as olfactory neurons from olfactory placode to the forebrain and hypothalamus during fetal life.,Structural olfactory tract abnormalities are well seen on MRI,INTRODUCTION:Kallmann syndrome,2,Kallmann综合征的MRI表现课件,3,Kallmann综合征的MRI表现课件,4,Kallmann综合征的MRI表现课件,5,Kallmann综合征的MRI表现课件,6,Kallmann综合征的MRI表现课件,7,Kallmann综合征的MRI表现课件,8,DISCUSSION:,Kallmann syndrome is an inherited disorder characterized by hypogonadotrophic hypogonadism and anosmia or hyposmia.,The inheritance may be X-linked, Autosomal recessive or Autosomal dominant with variable penetrance.,The reported incidence is 1 in 10,000 men and 1 in 50,000 women.,DISCUSSION:Kallmann syndrome i,9,Kallmann syndrome is an anomaly of neuronal migration.,Cells that differentiate into Gonadotrophin releasing hormone (GnRH) secreting neurons originate from within embryonic olfactory epithelium and migrate along fascicles of vomeronasal and terminalis nerves into forebrain.,Kallmann syndrome is an anomal,10,This migration of GnRH neurons is arrested in KS resulting in GnRH deficiency followed by different degrees of luteinizing hormone (LH) and follicle stimulating hormone (FSH) deficiencies.,Abnormal development of olfactory placode also results in improper development of olfactory bulbs and sulci.,This migration of GnRH neurons,11,diagnosis of KS in adults is fairly straightforward,depending on the co-existence of anosmia with subnormal levels of gonadal steroids and gonadotrophins.,However the diagnosis may be difficult to establish in patients of pre-pubertal age who may require genetic testing and MRI.,In such patients, MRI enables a presumptive diagnosis of KS to be made by demonstrating characteristic abnormalities in olfactory sulci and tracttory.,diagnosis of KS in adults is f,12,IMAGING,Morphological abnormalities of olfactory apparatus in KS are best evaluated with MRI.,High resolutions coronal fast spin echo T2W images are the preferred sequences for morphologic evaluation of the olfactory system.,Olfactory bulbs are optimally visualized in coronal planes.,IMAGINGMorphological abnormali,13,it is easier to appreciate anatomicalanomaliespresent in Kallmann syndrome by comparing it to a normal patient.,The normal anatomy of the region consists of the olfactory bulbs located in the olfactory grooves of the anterior cranial fossa.,The inferior surface of the frontal lobes usually consists gyrus rectu separated from the medial orbital gyrus (M) by the olfactory sulcus (yellow arrow).,it is easier to appreciate,14,o,Olfactory bulb:,blue arrows,gyrus rectus: R,the medial orbital gyrus : M,olfactory sulcus : yellow arrow,oOlfactory bulb: blue arrows,15,MRI FINDINGS:,hypoplasia of the olfactory bulbs with olfactory tracts present,aplasia of the olfactory bulbs with olfactory tracts present.,aplasia of both olfactory bulbs and olfactory tracts,MRI FINDINGS:hypoplasia of the,16,It was also described mild to moderate volume loss in temporal and frontal lobes,Hypoplasia of anterior pituitary may be secondary to limited stimulation due to absence of hypothalamic GnRH neurons.,Kallmann综合征的MRI表现课件,17,CONCLUSION:,Kallmanns syndrome is a rare genetic disorder.,High resolutions coronal fast spin echo T2W is the preferred sequences for morphologic evaluation of the olfactory system.,CONCLUSION:Kallmanns syndrome,18,Kallmann综合征的MRI表现课件,19,
展开阅读全文