Symmetry recovery in zygomaticomaxillary complex fractures compared to normal unfractured population: A new reliable 3D evaluation.

OBJECTIVE: This study aims to quantify the facial symmetry of surgically treated zygomaticomaxillary complex (ZMC) fractures through a new reliable three-dimensional evaluation method, which is crucial for improving post-operative aesthetic and functional outcomes. MATERIAL AND METHODS: Healthy patients and patients with surgically treated ZMC fractures were retrospectively reviewed. Using Brainlab Elements® the zygomatic bone and the orbit of each patient was segmented and mirrored. Subsequently, the mirrored side was matched with the other side via volume-based registration, using the segmented orbit as reference. Volumetric asymmetry was measured using 3-matic software, and a surface-based matching technique was used to calculate the mean absolute differences (MAD) between the surfaces of the two sides of the ZMC. The reliability of this novel method using volume-based registration was tested, and the intra-class correlation coefficient was assessed. RESULTS: The MAD between the surfaces of the left and right sides in the control group was 0.51 mm (±0.09). As for the ZMC fracture group, MAD was 0.78 mm (±0.20) and 0.72 mm (±0.15) pre- and post-operatively, respectively. The MAD showed statistically significant differences between pre- and post-operative groups (p = 0.005) and between control and post-operative groups (p < 0.001). The intra-class correlation coefficient was high (≥0.99). CONCLUSIONS: This evaluation method using mirroring and volume-based registration to determine the symmetrical position of the ZMC is reliable. The surface-based measurements revealed an improved symmetry after surgery. However, the symmetry of the treated patients remained lower than the control group.

Higher need for removal of osteosynthesis material after multi-piece versus one-piece Le Fort I osteotomy: A retrospective study of 339 patients.

The aim of the present study was to identify the risk factors for removal of osteosynthesis material after multi-piece Le Fort I osteotomy compared to standard one-piece Le Fort I osteotomy (LF1). Medical files of patients treated with multi-piece or one-piece LF1 were retrospectively reviewed, including the indication for removal and time between insertion and removal. A total of 339 patients were included: 290 patients with LF1 and 49 patients with multi-piece LF1. Patients undergoing multi-piece LF1 had 2.7-times significantly higher (p < 0.001) relative risk of osteosynthesis removal in the upper jaw (42.9%) than patients undergoing LF1 (15.9%). Significant independent predictors of removal of osteosynthesis material after multi-piece LF1 were older age (odds ratio [OR] 1.1, 95% confidence interval [CI] 1.0-1.2; p = 0.028), simultaneous bilateral sagittal split osteotomy (OR 7.8, 95% CI 1.2-50.3; p = 0.031), and no previous surgically assisted rapid palatal expansion (OR 0.14, 95% CI 0.03-0.69; p = 0.15). Significantly higher removal rates of osteosynthesis material were found after multi-piece LF1. Therefore, all patients must be informed of the higher risk for removal of osteosynthesis material when undergoing a multi-piece LF1.

Choroidal abnormalities in café-au-lait syndromes: a new differential diagnostic tool?

The best known café-au-lait syndrome is neurofibromatosis type 1 (NF1). Legius syndrome (LS) is another, rarer syndrome with café-au-lait macules (CALMs). In young patients their clinical picture is often indistinguishable. We investigated the presence of choroidal abnormalities in syndromes with CALMs as a candidate tool for a more efficient diagnosis. Thirty-four patients with NF1 (14 with a truncating mutation, 14 with a non-truncating mutation and 6 with unknown mutation) and 11 patients with LS. All patients underwent an ophthalmological examination. Infrared images were performed. Choroidal nodules were diagnosed in 65% of the NF1 group. About 71% of NF1 patients with a truncating mutation and 50% of patients with a non-truncating mutation were found to have nodules. Choroidal nodules were seen in 18% of the LS patients, never more than one nodule/eye was detected in this group. Choroidal nodules are more abundantly present in NF1 genotypes with truncating mutations. In contrast, the number of choroidal nodules in LS is comparable with their presence in healthy individuals. Especially at an early age, when the clinical picture is incomplete, the detection of choroidal nodules is of diagnostic value, and helps in an appropriate genetic counselling and follow-up. These results support the suggestion to include choroidal nodules to the diagnostic criteria for NF1.