Freeform fabrication of tissue-simulating phantom for potential use of surgical planning in conjoined twins separation surgery

Abstract

Preoperative assessment of tissue anatomy and accurate surgical planning is crucial in conjoined twin separation surgery. We developed a new method that combines three-dimensional (3D) printing, assembling, and casting to produce anatomic models of high fidelity for surgical planning. The related anatomic features of the conjoined twins were captured by computed tomography (CT), classified as five organ groups, and reconstructed as five computer models. Among these organ groups, the skeleton was produced by fused deposition modeling (FDM) using acrylonitrile-butadiene-styrene. For the other four organ groups, shell molds were prepared by FDM and cast with silica gel to simulate soft tissues, with contrast enhancement pigments added to simulate different CT and visual contrasts. The produced models were assembled, positioned firmly within a 3D printed shell mold simulating the skin boundary, and cast with transparent silica gel. The produced phantom was subject to further CT scan in comparison with that of the patient data for fidelity evaluation. Further data analysis showed that the produced model reassembled the geometric features of the original CT data with an overall mean deviation of less than 2 mm, indicating the clinical potential to use this method for surgical planning in conjoined twin separation surgery.

Recent advances on the development of phantoms using 3D printing for imaging with CT, MRI, PET, SPECT, and ultrasound

“…Shen et al developed a phantom composed of five organ groups, and for each of these groups the CT numbers were measured: −256 (skeleton), −600 (spinal nerve) #bib350 and 1050 (colon for two groups), 710 and 590 (kidney‐bladder for two groups), as well as 85 for other tissues.…”

“…The resolution is expressed in dots per inch (dpi) or micrometers (lm) and assessed by comparing the dimensions of the produced physical phantom with the original dimensions provided to the printer. Among the papers used, 10 have assessed the resolution or accuracy of the printer by quantitative (numerical) comparison, [26][27][28][29][30][31][32][33][34][35] 10 by qualitative (figural) comparison, 22,[36][37][38][39][40][41][42][43][44] and 14 by both quantitative and qualitative comparison. 10,21,[45][46][47][48][49][50][51][52][53][54][55][56] Sixteen of the research articles do not include a verification of the printers' resolutions.…”

Caso Clínico: Uso de Biomodelos Tridimensionales para la Planificación Preoperatoria de Tumores Craneales Fronto - orbitarios

“…Al realizar una búsqueda en Pubmed con los términos: "3D printing AND surgical AND planning" se encuentran 363 artículos (al 6 de diciembre del 2017), con un incremento exponencial en el número de publicaciones en los últimos años: La mayoría de los trabajos hacen referencia a su uso en cirugía e intervencionismo cardíaco [4,[15][16][17][18][19][20][21], pero provienen de práctica-mente todas las especialidades quirúrgicas, incluso varios artículos reportan su empleo y beneficios para planificar la separación de siameses [6,40,42].…”

“…En la actualidad son muchas las ramas quirúrgicas que se están beneficiando de las tecnologías de impresión 3D con estos fines alrededor del mundo, entre ellas neurocirugía [5,[8][9][10][11][12][13][14], cirugía cardíaca [4,[15][16][17][18][19][20][21], ortopédica [22][23][24][25][26][27], maxilofacial [28][29][30][31], otorrinolaringología [32][33][34], cirugía hepática [35][36][37], urológica [3,38,39], pediátrica [6,[40][41][42], ginecológica [43,44], plástica [45], torácica [46], cirugía general [47].…”

Automatic quantitative analysis of pulmonary vascular morphology in CT images

“…These phantoms can be created using 3D printing, a technique with applications in different imaging modalities, including CT, for imaging and dosimetry purposes. [26][27][28][29][30][31] In this work, a 3D printed phantom with vessel-like structures designed in a similar way to the lung was used to validate the proposed method for quantifying vessel morphology. A sufficiently high-resolution micro-CT scan of the lung phantom was acquired and used as the ground truth for the vessel distribution.…”