Noga J T, Bartley A J, Jones D W, Torrey E F, Weinberger D R
Clinical Brain Disorders Branch, DIRP, NIMH, NIH, Neuroscience Center at St. Elizabeth's, Washington, DC 20032, USA.
Schizophr Res. 1996 Oct 18;22(1):27-40. doi: 10.1016/0920-9964(96)00046-1.
This study combines recent advances in three-dimensional neuroimaging technology and the genetic constraints inherent in monozygotic (MZ) twins to examine surface gyral anatomy and gross brain dimensions in monozygotic twin pairs discordant for schizophrenia. Results are presented and evaluated with respect to prior observations of cortical anomalies in schizophrenia and the hypothesis that schizophrenia involves cortical maldevelopment.
Three-dimensional renderings from volumetric magnetic resonance imaging (MRI) data of 13 MZ twin pairs discordant for schizophrenia and nine normal MZ pairs were studied. Qualitative assessments of left and right hemisphere surfaces were made by raters blind to diagnosis in an effect to identify developmental gyral abnormalities such as vertical temporal gyri or microgyria. Measurement of brain hemisphere length, area, and volume were also determined. These data were compared within discordant MZ schizophrenia pairs, within normal MZ pairs, and between matched unaffected discordant and normal MZ groups.
Raters did not identify qualitatively abnormal gyri in the schizophrenia subjects to enable distinction from their unaffected co-twins or from normal controls. Brain hemisphere volumes in the affected DS were significantly smaller bilaterally by about 3% compared with their unaffected DS co-twins, who did not differ from normals on this measure.
We were unable to confirm previous reports of vertical gyri or localized gyral thinning as being characteristic of the cortical anatomy of schizophrenia. If cortical maldevelopment is associated with schizophrenia it does not appear to disrupt gross gyral pattern formation in these ways. The quantitative results of diminished hemisphere volume and length in the twins with schizophrenia are consistent with previous reports of smaller brain size in schizophrenia. Our results suggest that this is a bilateral phenomenon that may be dependent, at least in part, on environmental factors.
本研究结合了三维神经成像技术的最新进展以及同卵（MZ）双胞胎固有的遗传限制因素，以研究精神分裂症不一致的同卵双胞胎对的表面脑回解剖结构和大脑总体尺寸。根据先前对精神分裂症皮质异常的观察结果以及精神分裂症涉及皮质发育异常的假设，对结果进行了呈现和评估。
研究了13对精神分裂症不一致的MZ双胞胎对和9对正常MZ双胞胎对的容积磁共振成像（MRI）数据的三维渲染图。由对诊断不知情的评估人员对左右半球表面进行定性评估，以识别发育性脑回异常，如垂直颞回或微小脑回。还确定了脑半球长度、面积和体积的测量值。将这些数据在不一致的MZ精神分裂症双胞胎对、正常MZ双胞胎对以及匹配的未受影响的不一致和正常MZ组之间进行比较。
评估人员未在精神分裂症受试者中识别出定性异常的脑回，无法将其与未受影响的同卵双胞胎或正常对照组区分开来。与未受影响的同卵双胞胎相比，受影响的精神分裂症患者双侧脑半球体积明显小约3%，而未受影响的同卵双胞胎在该测量指标上与正常人无差异。
我们无法证实先前关于垂直脑回或局限性脑回变薄是精神分裂症皮质解剖特征的报道。如果皮质发育异常与精神分裂症相关，那么它似乎不会以这些方式破坏脑回的总体模式形成。精神分裂症双胞胎脑半球体积和长度减小的定量结果与先前关于精神分裂症患者脑体积较小的报道一致。我们的结果表明，这是一种双侧现象，可能至少部分取决于环境因素。
