T o determine the development of the convolutional pattern of the cerebral hemispheres, we have examined multiple gross photographs of 507 brains and serial sections of 207 brains from infants of 10 to 44 weeks' gestational age. T h e sequential developmental changes of the individual fissures, sulci, and gyri of the cerebral hemispheres throughout the gestational period are tabulated. Schematic drawings made from enlarged photographs show the major changes associated with each month of the second and third trimesters.T h e brains of twins between 19 and 32 weeks' gestational age show a delay of approximately two to three weeks i n the development of convolutional markings compared with the brains of nontwins. There is no significant difference between male and female brains.We found left-right asymmetries of the transverse temporal gyri, sylvian fissures, and planum temporale. I n general, the right cerebral hemisphere shows gyral complexity earlier than the left. Our findings allow speculation about the significance of left-right asymmetry of the brain as i t affects speech and language development.Chi JG, Dooling EC, Gilles FH: Gyral clevelopment of the human brain. A n n Neurol 1: [86][87][88][89][90][91][92][93] 1977 It is helpful t o use all available measurements when o n e tries t o assess the degree of maturity of an immature infant, whether clinically o r at necropsy. to 44 weeks.* T h e data so obtained provide standards of reference that can be used to determine whether brains of a given gestational age deviate from the "norm" or show an abnormality of external development. A n abstract has already appeared [41. Material and MethodsAs part of the Collabnrdrive Perinatal ProJect, brains of infants were selected by Dr Paul I Yakovlev for serial sectioning. According to a standardized protocol [ 5 ] , the brains were fixed in formaldehyde, photographed, em-"Gestational age was calculated with reference to the date of the last menstrual period given by the mother when she regisrered in the study. This was standard procedure for all participating study institutions. bedded in celloidin, and cut serially at thicknesses varying from 15 to 30 p, according to the size of the specimen. Every fifth, tenth, or twentieth section was stained for myelin by the Loyez method, and its adjacent section was stained by the Nissl method.After excluding brains with obvious malformdtionsanencephaly, hydranencephaly, hydrocephalus, or any distorted by hemorrhage or necrosis-we studied 207 serially sectioned brains. Thc sex distribution was nearly equal. About 6 0 F of the brains were cut in the frontal plane, 20% horizontally, and 2 0 Y sagitally.Photographs of the fixed brains before sectioning, showing the righc and left lateral, dorsal, and basal aspects, were available for study. We also had photographs of an additional 300 brains from the Collaborative Perinatal Project before they were cut into special blocks nonserially and stained. These photographs showed the external aspects and included coronal sections cut a...

Rathke cleft cysts are associated with a variety of clinical presentations and sometimes confusing intraoperative and pathological findings. Close postoperative observation with neuroimaging and neuroophthalmological assessment is necessary, especially after a partial removal, as in cases with squamous metaplasia.

Acute chorioamnionitis (ACA) is a well-established lesion of the placenta in cases with intra-amniotic infection. In contrast, the clinicopathologic significance of chronic chorioamnionitis (CCA) is unclear. This study was conducted to determine the frequency and severity of CCA in normal pregnancy and various pregnancy complications. Placentas from the following patient groups were studied: 1) term not in labor (TNL; n=100), 2) term in labor (TIL; n=100), 3) preterm labor (PTL; n=100), 4) preterm prelabor rupture of the membranes (PPROM; n=100), 5) preeclampsia at term (TPE; n=100), 6) preterm preeclampsia (PPE; n=100), and 7) small-for-gestational-age at term (SGA; n=100). Amniotic fluid CXCL10 concentration was measured in 64 patients. CXCL9, CXCL10, and CXCL11 mRNA expressions in the chorioamniotic membranes were assessed by real-time quantitative RT-PCR. The frequency of CCA in PTL and PPROM groups was 34% and 39%, respectively, which was higher than those of normal term placentas (TNL 19%, TIL 8%; p<0.05 each). The frequency of CCA in TPE, PPE and SGA groups was 23%, 16%, and 13%, respectively. Concomitant villitis of unknown etiology (VUE) was found in 38.2% and 35.9% of PTL and PPROM cases with CCA, respectively. Interestingly, the median gestational age of preterm CCA cases was higher than that of ACA cases (p<0.05). The median amniotic fluid CXCL10 concentration was higher in cases with CCA than in those without, in both PTL and PPROM groups (p<0.05 and p<0.01, respectively). CXCL9, CXCL10, and CXCL11 mRNA expression in the chorioamniotic membranes was also higher in CCA cases than in those without CCA (p<0.05). We propose that CCA defines a common placental pathologic lesion among the PTL and PPROM groups, especially in cases of late preterm birth. Its association with VUE and the chemokine profile in amniotic fluid suggests an immunological origin, akin to transplantation rejection and graft-versus-host disease in the chorioamniotic membranes.

Left-right asymmetries of the transverse temporal (Heschl) gyri and the temporal plane become recognizable by 31 weeks' gestation. The transverse temporal gyri are larger in number and extent on the right side in 54% of 207 serially sectioned fetal brains ranging in gestational age from 10 to 44 weeks, and the temporal plane is larger on the left side in those brains. There are two transverse temporal gyri on the left and a single right transverse temporal gyrus on the right in 18% of the brains. No asymmetry of number of transverse temporal gyri or extent of the temporal plane is apparent in 28%. These findings, which confirm those in adult brains, suggest that anatomical asymmetries for left hemispheral speech and language dominance may be established during the last trimester of fetal life.

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