Skeletal abnormalities in fetuses with Down's syndrome: a radiographic post-mortem study.

OBJECTIVE: To evaluate skeletal abnormalities on post-mortem radiographs of fetuses with Down's syndrome. MATERIALS AND METHODS: Biometrical and morphological criteria, which are used for US prenatal detection of trisomy 21, were assessed. Limb long bones, biparietal diameter (BPD)/occipito-frontal diameter (OFD) ratio, ossification of nasal bones and appearance of the middle phalanx of the fifth digit (P2) in 60 fetuses with Down's syndrome were analysed and compared with 82 normal fetuses matched for gestational age (GA) from 15 to 40 weeks' gestation (WG). RESULTS: We observed reduced growth velocity of limb long bones during the third trimester in both groups, but the reduction was more pronounced in the trisomic group. Brachycephaly was found as early as 15 WG in Down's syndrome and continued throughout gestation (sensitivity 0.28, specificity 1). Ossification of the nasal bones, which can be detected in normal fetuses from 14 WG, was absent in one quarter of trisomic fetuses, regardless of GA. The middle phalanx of the fifth digit was evaluated by comparison with the distal phalanx (P3) of the same digit. We found that P2 was not ossified in 11/31 trisomic fetuses before 23 WG, and was either not ossified or hypoplastic in 17/29 cases after 24 WG (sensitivity 0.56, specificity 1). CONCLUSIONS: Three key skeletal signs were present in trisomic fetuses: brachycephaly, absence of nasal bone ossification, and hypoplasia of the middle phalanx of the fifth digit. All these signs are appropriate to prenatal US screening. When present, they fully justify determination of the fetal karyotype by amniocentesis.

Aneurysmal bone cysts: percutaneous embolization with an alcoholic solution of zein--series of 18 cases.

PURPOSE: To assess the efficacy of percutaneous embolization with an alcoholic solution of zein in the treatment of aneurysmal bone cysts. MATERIALS AND METHODS: Eighteen patients with aneurysmal bone cysts were treated percutaneously with alcoholic zein. The cysts were in the lower limb (n = 7), upper limb (n = 5), pelvis (n = 3), cervical spine (n = 2), and mandible (n = 1). All patients were symptomatic, three had previously undergone surgery. Percutaneous embolization was performed with fluoroscopic or computed tomographic guidance with the patient under general anesthesia. Clinical and imaging follow-up lasted 18 months to 4 years. RESULTS: Percutaneous embolization was performed in 16 cases. In two cases, cystograms showed marked venous drainage and thus embolization was not attempted. Six patients underwent repeat embolization. Complications consisted of a local transitory inflammatory reaction (n = 5), aseptic osteitis (n = 1), and a small pulmonary infarct without sequelae (n = 1). Relief of symptoms was achieved in all patients except one, who underwent surgery. At imaging, improvement was total in 13 cases (87%) and partial in two cases (13%). No recurrence was noted during follow-up. CONCLUSION: Percutaneous embolization of aneurysmal bone cysts with alcoholic zein should be considered a reliable alternative to surgery, especially in cases with a difficult surgical approach or cases of postsurgical recurrence.

In utero fetal cerebral intraparenchymal ischemia diagnosed by nuclear magnetic resonance.

Fetal brain damage can have many causes, the most common being possibly asphyxia which is often associated with intrauterine growth retardation. Early recognition of cerebral lesions is important in guiding obstetrical management. A case of antenatal cerebral intraparenchymal ischemia diagnosed by nuclear magnetic resonance (NMR) earlier than cerebral ultrasound examination is reported. This case report indicates that NMR may be a useful tool for the early detection of cerebral impairment in severe fetal growth retardation.

Highly differentiated teratoma and fetus-in-fetu: a single pathology?

A case of sacrococcygeal teratoma is presented with characteristics of fetus-in-fetu. This pseudo-fetus presented a rudimentary single cavity heart, which beat at a different rate to that of the affected infant. X-ray examination showed no spinal column. This case confirms that fetus in fetu can be a remarkably complex, well-differentiated, highly organized teratoma.

Fetal bone age revisited: proposal of a new radiographic score.

In order to establish a fetal bone age score, the post-mortem skeletal radiographs of 85 selected normal fetuses aged from 15 to 41 weeks of gestation (WG) were analysed. Twenty-eight skeletal areas were selected for which quantitative and/or qualitative criteria were defined. Each new aspect was graded and statistically tested by the stepwise linear regression method. Two modalities of scores and decreasing complexity were then designed. The use of these two scores permitted the assessment of the fetal age with r2 values of 0.97 and 0.96 (standard error of estimation of 1.19 and 1.36 WG). Applied to 15 intrauterine growth retardation (IUGR) fetuses, the age estimated by these scores was well correlated with the age obtained by extraosseous criteria of maturation. This method is proposed as a tool for determining, the fetal age during necropsy and could also be useful in US prenatal evaluation.