ABSTRACT
BACKGROUND: 3-dimensional (3D) printing carries a genuine potential for pre-operative planning in neurosurgery. Entry-level 3D printers offer practicality in low resource settings, but are often limited by the range of filament materials as well as the capability of open-source segmentation software. OBJECTIVE: We intended to demonstrate that 3D printing of neuroanatomical structures is possible using an entry-level 3D printer equipped with the direct drive (DD) modification, which supported flexible filaments, with the models segmented using an open-source software. METHODS: A DD system was installed onto the Ender 3 Pro printer. An attempt to print neurosurgical models using a low-cost 3D printer was conducted, where four patient-based neuroanatomical models were printed: skull base-vasculature, skull base-tumour, cervical spine, and ventricular system. The results were discussed and compared to similar endeavours in past literature. RESULTS: Although DD installation was challenging and led to vibration and longer print time, which ultimately warranted an inferior printing speed, DD system enabled the printing with thermoplastic polyurethane (TPU), a versatile elastomer; in addition to producing equal amount of detail to those printed with high-end printers and advanced image segmentation software. Fitting the frame well, changing infill type, and avoiding warping and stringing will improve print quality with the DD system. CONCLUSION: 3D printing with entry-level 3D printers equipped with DD system has been proven to be a reliable way of accurately reproducing patient-specific neuroanatomical constructs. Follow-up studies are necessary to implement 3D printing for neurosurgical planning in low-resource settings.
Subject(s)
Neurosurgery , Humans , Printing, Three-Dimensional , Software , Skull Base , NeuroanatomyABSTRACT
OBJECTIVE: To evaluate the accuracy and the effect of drill guide template for pedicle screw placement in severe scoliosis. METHOD: Eight patients with rigid scoliosis were enrolled, five males and three females, ranging from nine to 23 years old. A three-dimensional CT scan of the spine was performed and saved as a DICOM file type. The multi-level template was designed by Mimics software and manufactured according to the part of the most severe deformity. The drill template was placed on the corresponding vertebral surface. Pedicle screws were carefully inserted across the trajectory of the template. Postoperatively, the positions of the pedicle screws were evaluated by CT scan and graded for validation. RESULTS: No spinal cord injury or nerve damage occurred. All patients had satisfactory outcomes. The abnormalities and the measures observed during operation were the same as those found in the preoperative period. The position of the pedicle screws was accurate, according to the postoperative X-ray and CT scan. The rate of scoliosis correction was 60%. Compared with controls, surgery time, blood loss and radiation were significantly lower. CONCLUSION: With the application of multi-level template, the placement of pedicle screws shows high accuracy in scoliosis with shorter surgical time, less blood loss and less radiation exposure. Level of Evidence III, Retrospective Comparative Study.
OBJETIVO: Avaliar a precisão e o efeito da matriz de guia de broca para colocação de parafuso pedicular em escoliose grave. MÉTODO: Oito pacientes com escoliose rígida foram selecionados, sendo cinco homens e três mulheres na faixa etária de nove a 23 anos. Foi realizada TC tridimensional da coluna, gravada no formato DICOM. A matriz multinível foi desenhada pelo software Mimics e fabricada de acordo com a parte da deformidade mais grave. A matriz da broca foi colocada na superfície vertebral correspondente. Os parafusos pediculares foram cuidadosamente inseridos ao longo da trajetória da matriz. No pós-operatório, as posições dos parafusos pediculares foram avaliadas por TC e classificadas para validação. RESULTADOS: Não ocorreu nenhuma lesão da medula espinhal nem lesão de nervos. Todos os pacientes tiveram desfechos satisfatórios. As anormalidades e as medidas observadas durante a operação foram as mesmas encontradas no pré-operatório. A posição dos parafusos pediculares foi precisa, de acordo com a radiografia e a TC pós-operatórias. A taxa de correção de escoliose foi de 60%. Em comparação com os controles, o tempo de cirurgia, a perda de sangue e a radiação foram significantemente menores. CONCLUSÃO: Com a aplicação da matriz multinível, a colocação dos parafusos pediculares mostra alta precisão na escoliose, com menor tempo cirúrgico, menos perda de sangue e menor exposição à radiação. Nível de Evidência III, Estudo Retrospectivo Comparativo.
ABSTRACT
ABSTRACT Objective: To evaluate the accuracy and the effect of drill guide template for pedicle screw placement in severe scoliosis. Method: Eight patients with rigid scoliosis were enrolled, five males and three females, ranging from nine to 23 years old. A three-dimensional CT scan of the spine was performed and saved as a DICOM file type. The multi-level template was designed by Mimics software and manufactured according to the part of the most severe deformity. The drill template was placed on the corresponding vertebral surface. Pedicle screws were carefully inserted across the trajectory of the template. Postoperatively, the positions of the pedicle screws were evaluated by CT scan and graded for validation. Results: No spinal cord injury or nerve damage occurred. All patients had satisfactory outcomes. The abnormalities and the measures observed during operation were the same as those found in the preoperative period. The position of the pedicle screws was accurate, according to the postoperative X-ray and CT scan. The rate of scoliosis correction was 60%. Compared with controls, surgery time, blood loss and radiation were significantly lower. Conclusion: With the application of multi-level template, the placement of pedicle screws shows high accuracy in scoliosis with shorter surgical time, less blood loss and less radiation exposure. Level of Evidence III, Retrospective Comparative Study.
RESUMO Objetivo: Avaliar a precisão e o efeito da matriz de guia de broca para colocação de parafuso pedicular em escoliose grave. Método: Oito pacientes com escoliose rígida foram selecionados, sendo cinco homens e três mulheres na faixa etária de nove a 23 anos. Foi realizada TC tridimensional da coluna, gravada no formato DICOM. A matriz multinível foi desenhada pelo software Mimics e fabricada de acordo com a parte da deformidade mais grave. A matriz da broca foi colocada na superfície vertebral correspondente. Os parafusos pediculares foram cuidadosamente inseridos ao longo da trajetória da matriz. No pós-operatório, as posições dos parafusos pediculares foram avaliadas por TC e classificadas para validação. Resultados: Não ocorreu nenhuma lesão da medula espinhal nem lesão de nervos. Todos os pacientes tiveram desfechos satisfatórios. As anormalidades e as medidas observadas durante a operação foram as mesmas encontradas no pré-operatório. A posição dos parafusos pediculares foi precisa, de acordo com a radiografia e a TC pós-operatórias. A taxa de correção de escoliose foi de 60%. Em comparação com os controles, o tempo de cirurgia, a perda de sangue e a radiação foram significantemente menores. Conclusão: Com a aplicação da matriz multinível, a colocação dos parafusos pediculares mostra alta precisão na escoliose, com menor tempo cirúrgico, menos perda de sangue e menor exposição à radiação. Nível de Evidência III, Estudo Retrospectivo Comparativo.
ABSTRACT
Background Orbital blow-out fracture often results in the abnormalities of appearance and function of eye.Because of the special and complex anatomical structure of orbital cavity,it is difficult to design and manufacture the corresponding orbital implants.The computer-aided designing and manufacturing (CADM) technology provides a new approach to orbital implants.However,the clinical value of this method is still under evaluation.Objective This study was to investigate the application and the therapeutic effect of CADM for orbital blow-out fracture.Methods The clinical data of 74 eyes of 74 patients who received surgery for orbital blow-out fracture from July 2006 to July 2012 in Henan Eye Institute,Henan Eye Hospital were retrospectively analyzed.Fiftyeight patients underwent CADM implanted surgery and 16 patients received non-CADM surgery in the same period with matched age,gender and lateral eyes in both groups.The individualized 3D orbital implants were designed and manufactured by the technology of CADM and then were implanted in the bone defects in the CADM group,while the traditional hydroxyapatite artificial bone or high density porous polyethylene material (Medpor) was utilized in the non-CADM group with a fellow-up duration for 22 to 69 months.The best corrected visual acuity (BCVA),eyeball exophthalmos,ocular position,eye movement,diplopia and postoperative complications were evaluated.Results The preoperative BCVA were 0.71±0.37 and 0.69±0.41,and the postoperative BCVA were 0.74±0.38 and 0.72±0.41 in the CADM group and the non-CADM group,respectively,showing an insignificant intergroup difference (Fgroup =0.043,P=0.837),but a significant variation was found over time (Ftime =13.576,P ＜ 0.01).The BCVA was significantly improved after surgery compared with before surgery in both groups (both at P＜0.05).No significantdifferences were found in the number of eyes with curative and improved diplopia and eye movement disorders between the two groups during the fellow-up duration (Z =-0.298,P =0.766;Z =-0.548,P =0.584).The preoperative eyeball exophthalmos values were (3.93±0.99)mm and (3.88±0.97)mm and the postoperative ones were (0.91 ±0.67)mmand (1.84±0.80) mm in the CADM group and the non-CADM group,respectively,without significant differencebetween the two groups (Fgroup =3.558,P =0.063).However,the eyeball exophthalmos values after operation wereremarkably lower than those before operation in both groups (both at P＜0.05).CT imaging displayed implants fitting well with fracture defect and attached to bone tissue accurately in all of the eyes in the CADM group,but in the nonCADM group,the bulge of implants damaging extraocular muscles or optical nerve was found in 2 eyes.No postoperative complication was seen throughout the fellow-up duration in the CADM group.Conclusions CADM technology for orbital blow-out fracture can reconstruct a 3D bony orbit and effectively repair ocular position and appearance,and furthermore restore eye movement and visual functions.The therapeutic outcome of CADM technology for orbital blow-out fracture is superior to conventional implants.
