Stereolithographic biomodeling to create tangible hard copies of cardiac structures from echocardiographic data: in vitro and in vivo validation.

OBJECTIVES: This study investigated the feasibility, accuracy and clinical potential of creating polymer hard copies of echocardiographic data using stereolithography. BACKGROUND: Three-dimensional (3D) echocardiography has so far been limited by the need to display reconstructed 3D objects on a two-dimensional screen. Thus, tangible stereolithographic polymer models created from echocardiographic data could enhance our spatial perception of cardiac anatomy and pathology. METHODS: Hard-copy replicas of water-filled latex balloon phantoms (n = 7) and porcine liver specimens (n = 12) were generated from echocardiographic images using stereolithography (computerized laser polymerization). In addition, we created 24 models of the mitral valve from 12 transesophageal studies (normal = 6, mitral stenosis n = 4, prolapse/flail leaflet n = 8, annular dilation n = 2, leaflet restriction n = 2 and following mitral valve repair n = 2). RESULTS: Excellent agreement was found for comparison of volumes (r = 0.98, SEE = 3.46 mm3, mean difference = 0.25 +/- 3.33 mm3) and maximal dimensions (r = 0.99, SEE = 0.16 cm, mean difference = 0.03 +/- 0.16 cm) between phantoms and their corresponding replicas. Visual and tactile examination of mitral valve models by two blinded observers allowed correct depiction of mitral valve anatomy and pathology in all cases. CONCLUSIONS: Stereolithographic modeling of echocardiographic images is feasible and provides tangible polyacrylic models that are true to scale, shape and volume. Such models offer accurate depiction of mitral valve anatomy and pathology in patients studied with transesophageal echocardiography. This technique could have substantial impact on diagnosis, management and preoperative planning in complex cardiovascular disorders.

Flap surgery: experience with 1,030 operations and cephalometric investigation.

The authors report 1,030 (velo)pharyngoplasties performed in 40 years. The anatomical result was good in 98%, hyperrhinophony ceased or became minimal in 90% after surgery. The surgical indication and technique, the operative complications and the factors influencing the functional effect are discussed. In the present investigation cephalograms of 53 unilateral cleft lip and palate (UCLP) patients with inferiorly based pharyngeal flap were compared with the cephalograms of 38 UCLP patients without pharyngeal flap operation. Pharyngeal flap surgery has an adverse effect on the growing face both in the sagittal and vertical dimensions, but the changes do not reach a degree that would justify the abandonment of the good functional effect of velopharyngoplasty.

[Cranial structure in unilateral complete cleft lip and palate in children 8-12 years of age]. / 8-12 év közötti teljes egyoldali ajak- és szájpadhasadékos betegek koponyafelépítése.

The tele-X-ray photographs of 108 patients with single-sided cleft lips and palate were compared with 71 normal controls. The examination proved that a basic crane structure difference can be found between the groups. The group with cleft has a characteristic face with significant skeletal and dental changes. Such features have to be considered in the course of habilitation.

[Craniofacial morphology of the complete unilateral cleft lip and palate between the ages of 8-12]. / Morphologia tou kranioprosopikou sympleumatos se atoma me plere eteropleure cheileo-yperoioschistia, elikias 8-12 eton.

108 cephalograms of complete unilateral cleft lip and palate patients, divided into two groups according to ages, had been compared to 71 normal controls. The study demonstrated that there are basic differences in facial morphology between the groups. The cleft sample has a retrognathic facial configuration with significantly different skeletal sagittal and vertical trend compared to the normal. There are also compensatory dental disorders.