METHODS: Two 3D printed models were designed and fabricated using actual patient imaging data with reference marker points embedded artificially within these models that were then registered to a surgical navigation system using 3 different methods. The first method uses a conventional manual registration, using the actual patient's imaging data. The second method is done by directly scanning the created model using intraoperative computed tomography followed by registering the model to a new imaging dataset manually. The third is similar to the second method of scanning the model but eventually uses an automatic registration technique. The errors for each experiment were then calculated based on the distance of the surgical navigation probe from the respective positions of the embedded marker points.

RESULTS: Errors were found in the preparation and printing techniques, largely depending on the orientation of the printed segment and postprocessing, but these were relatively small. Larger errors were noted based on a couple of variables: if the models were registered using the original patient imaging data as opposed to using the imaging data from directly scanning the model (1.28 mm vs. 1.082 mm), and the accuracy was best using the automated registration techniques (0.74 mm).

AIM: To systematically review all available evidence to describe the incidence, clinical course with management and propose a definition.

METHODS: The databases PubMed, EMBASE and Cochrane databases were searched using with the keywords up to June 2020. Additional manual search was performed and cross-checked for additional references. Data collected included demographics, reason for colonoscopy, time to diagnosis, method of diagnosis (clinical vs imaging) and management outcomes.

RESULTS: A total of nine studies were included in the final systematic review with a total of 339 cases. The time to diagnosis post-colonoscopy ranged from 2 h to 30 d. Clinical presentation for these patients were non-specific including abdominal pain, nausea/vomiting, per rectal bleeding and chills/fever. Majority of the cases were diagnosed based on computed tomography scan. The management for these patients were similar to the usual patients presenting with diverticulitis where most resolve with non-operative intervention (i.e., antibiotics and bowel rest).

STUDY DESIGN: Experimental.

SAMPLE POPULATION: Fourteen equine cadaver limbs/horses.

METHODS: Simulated fractures were repaired with 2 lag screws under 4-Nm insertion torque (linear repair). Computed tomography (CT) imaging was performed with the leg unloaded and loaded to forces generated while walking. The fracture repair was revised to include 3 lag screws placed with the same insertion torque (triangular repair) prior to CT. The width of the fracture gap was assessed qualitatively by 2 observers and graded on the basis of gap measurements relative to the average voxel size at dorsal, mid, and palmar P1 sites. Interobserver agreement was assessed with Cohen's κ. The effect of repair type, loading condition, and measurement site on fracture gap grades was evaluated by using Kendall's τ-b correlation coefficients and paired nonparametric tests. Significance was set at P ≤ .05.