Computer-aided 3-D simulation and prediction of craniofacial surgery: a new approach.

BACKGROUND: In plastic and reconstructive craniofacial surgery, careful preoperative planning is essential. In complex cases of craniofacial synostosis, rapid prototyping models are used to simulate the surgery and reduce operating time. Recently, 3-D CT model surgery has been introduced for presurgical planning and prediction of the postoperative result. OBJECTIVE: For simulation of craniofacial surgery a computer-based system was developed that allows visualization and manipulation of CT-data using computer graphics techniques. Surgical procedures in all areas of the bony skull can be performed interactively. RESULTS: The case of a child with scaphocephalus is presented. Surgery is planned using the craniofacial surgery simulator described above. CONCLUSION: The computer-based interactive surgery simulation systems presented here allow precise visualization of craniofacial surgery. The accurate computer-aided 3-D simulation of bone displacements is also the prerequisite for transfer of the simulated surgery using a navigation system for surgery. Thus the preoperatively planned procedure could be transferred directly to the operating table.

Prognosis of children born to mothers with HELLP-syndrome.

In literature there have been differences in the assessment of the outcome of children born to mothers with HELLP syndrome. In a retrospective study we investigated six annual groups (1989-1994) at the Perinatal Center in Erlangen (11,235 births, 68 children of mothers with HELLP syndrome), 53 children were treated in our neonatal intensive care unit (NICU). The control group (n = 219) consisted of a complete age group in our NICU. The gestational age (mean 33 weeks, p < 0.003) and the birth weight (mean 1671 g, p < 0.001) were significantly lower in the HELLP group. No significant differences were detected with respect to the frequency of leucocytopenia (p = 0.518) and thrombocytopenia (p = 0.215). Despite a relatively high rate (37.7%) of RDS there was only a significant tendency to the disadvantage of HELLP children (p = 0.075). There was no difference in frequency of intracranial hemorrhage (ICH) (p = 0.566). Infections were diagnosed less frequently in HELLP children (p = 0.042). Mortality in the control group was higher only as a tendency (p = 0.07). The follow-up examinations of the neurological development covered 31 of the 53 treated children. After 6-72 months (median 24 months), 90.3% of these children showed normal development or only minor disabilities. The prognosis of children of mothers with HELLP syndrome is not as bad as has been assumed so far.