A New Classification of Three-Dimensional Printing Technologies: Systematic Review of Three-Dimensional Printing for Patient-Specific Craniomaxillofacial Surgery.

BACKGROUND: Three-dimensional printing technology has been advancing in surgical applications. This systematic review examines its patient-specific applications in craniomaxillofacial surgery. METHODS: Terms related to "three-dimensional printing" and "surgery" were searched on PubMed on May 4, 2015; 313 unique articles were returned. Inclusion and exclusion criteria concentrated on patient-specific surgical applications, yielding 141 full-text articles, of which 33 craniomaxillofacial articles were analyzed. RESULTS: Thirty-three articles included 315 patients who underwent three-dimensional printing-assisted operations. The most common modeling software was Mimics, the most common printing software was 3D Systems, the average time to create a printed object was 18.9 hours (range, 1.5 to 96 hours), and the average cost of a printed object was $1353.31 (range, $69.75 to $5500). Surgical procedures were divided among 203 craniofacial patients (205 three-dimensional printing objects) and 112 maxillofacial patients (137 objects). Printing technologies could be classified as contour models, guides, splints, and implants. For craniofacial patients, 173 contour models (84 percent), 13 guides (6 percent), two splints (1 percent), and 17 implants (8 percent) were made. For maxillofacial patients, 41 contour models (30 percent), 48 guides (35 percent), 40 splints (29 percent), and eight implants (6 percent) were made. These distributions were significantly different (p < 0.0001). Four studies compared three-dimensional printing techniques to conventional techniques; two of them found that three-dimensional printing produced improved outcomes. CONCLUSIONS: Three-dimensional printing technology in craniomaxillofacial surgery can be classified into contour models (type I), guides (type II), splints (type III), and implants (type IV). These four methods vary in their use between craniofacial and maxillofacial surgery, reflecting their different goals. This understanding may help advance and predict three-dimensional printing applications for other types of plastic surgery and beyond.

Bilateral first rib resection and scalenectomy is effective for treatment of thoracic outlet syndrome.

OBJECTIVE: Because of the small numbers of thoracic outlet syndrome (TOS) patients treated with bilateral first rib resection and scalenectomy (FRRS), this patient subset has not been well studied. We examined a large cohort of TOS patients who underwent bilateral FRRS to evaluate patient characteristics and outcomes. METHODS: Patients treated with bilateral FRRS at Johns Hopkins Medical Institutions from 2003 to 2012 were identified by review of a prospectively maintained database. Statistical analysis compared patients with unilateral and bilateral FRRS and bilateral patients with different TOS indications. RESULTS: Fifty-three patients underwent bilateral FRRS with a mean follow-up of 11.4 months. Average time between operations was 17.0 months (range, 5.1-59.8 months). Compared with 408 unilateral FRRS patients, bilateral patients were younger (30 vs 35 years; P = .012), with no significant difference in gender. Among patients with dual-sided FRRS, 25 (47%) had bilateral neurogenic symptoms, 2 (4%) had bilateral arterial symptoms, and 26 (49%) had venous symptoms with the first side due to intermittent compression in 5 (second side: four, intermittent compression; one, neurogenic) and effort thrombosis in 21 (second side: 9, effort thrombosis; 8, intermittent compression; 4, neurogenic). Ten patients had prophylactic FRRS to prevent contralateral venous or arterial thrombosis, and eight had cervical ribs. Compared with neurogenic patients, venous patients were younger (25 vs 35 years; P < .001), with a trend toward more competitive athletes (seven venous vs two neurogenic). Symptomatic restenosis requiring dilation occurred after four FRRS for venous symptoms at a mean of 32.4 months, and rethrombosis occurred after four FRRS at a mean of 4 weeks (one treated with warfarin, three with tissue plasminogen activator), all on the primary side. Overall, 88% of FRRS for symptomatic TOS led to resolved symptoms at last follow-up. CONCLUSIONS: Bilateral FRRS is an effective method for treatment of TOS. Venous bilateral patients more often are younger, are competitive athletes, and require close postoperative monitoring for recurrent stenosis and thrombosis.