Adaptable cascaded registration for personalized maxilla completion and cleft defect volume estimation.

BACKGROUND: Cone-beam computed tomography (CBCT) images provide high-resolution insights into the underlying craniofacial anomaly in patients with cleft lip and palate (CLP), requiring non-negligible annotation costs to measure the cleft defect for the guidance of the clinical secondary alveolar bone graft procedures. Considering the cumbersome volumetric image acquisition, there is a lack of paired CLP CBCTs and normal CBCTs for learning-based anatomical structure restoration models. Nowadays, the registration-based method relieves the annotation burden, though one-shot registration and the regular mask are limited to handling fine-grained shape variations and harmony between restored bony tissues and the defected maxilla. PURPOSE: This study aimed to design and evaluate a novel method for deformable partial registration of the CLP CBCTs and normal CBCTs, enabling personalized maxilla completion and cleft defect volume prediction from CLP CBCTs. METHODS: We proposed an adaptable deep registration framework for personalized maxilla completion and cleft defect volume prediction from CLP CBCTs. The key ingredient was a cascaded partial registration to exploit the maxillary morphology prior and attribute transfer. Cascaded registration with coarse-to-fine registration fields handled morphological variations of cleft defects and fine-grained maxillary restoration. We designed an adaptable cleft defect mask and volumetric Boolean operators for reliable voxel filling of the defected maxilla. A total of 36 clinically obtained CLP CBCTs were used to train and validate the proposed model, among which 22 CLP CBCTs were used to generate a training dataset with 440 synthetic CBCTs by B-spline deformation-based data augmentation and the remaining for testing. The proposed model was evaluated on maxilla completion and cleft defect volume prediction from clinically obtained unilateral and bilateral CLP CBCTs. RESULTS: Extensive experiments demonstrated the effectiveness of the adaptable cleft defect mask and the cascaded partial registration on maxilla completion and cleft defect volume prediction. The proposed method achieved state-of-the-art performances with the Dice similarity coefficient of 0.90 ± $\pm$ 0.02 on the restored maxilla and 0.84 ± $\pm$ 0.04 on the estimated cleft defect, respectively. The average Hausdorff distance between the estimated cleft defect and the manually annotated ground truth was 0.30 ± $\pm$ 0.08 mm. The relative volume error of the cleft defect was 0.09 ± $0.09\pm$ 0.08. The proposed model allowed for the prediction of cleft defect maps that were in line with the ground truth in the challenging unilateral and bilateral CLP CBCTs. CONCLUSIONS: The results suggest that the proposed adaptable deep registration model enables patient-specific maxilla completion and automatic annotation of cleft defects, relieving tedious voxel-wise annotation and image acquisition burdens.

Magnetic resonance imaging of knees: a novel approach to predict recombinant human growth hormone therapy response in short-stature children in late puberty.

BACKGROUND: There is no appropriate tool to predict recombinant human growth hormone (rhGH) response before therapy initiation in short-stature children in late puberty. The current study aimed to explore the associations between magnetic resonance imaging (MRI) stages of the knee growth plates and rhGH response in short-stature children in late puberty. METHODS: In this prospective cohort study, short-stature children in late puberty were treated with rhGH and followed up for 6 months. We proposed a novel knee MRI staging system according to the growth plate states of distal femurs or proximal tibias and divided the participants into three groups: unclosed growth plate group, marginally closed growth plate group, and nearly closed growth plate group. The primary outcomes were height gain and growth velocity (GV), which were assessed three months later. RESULTS: Fifty participants were enrolled, including 23 boys and 27 girls. GV and height gain after 6 months of rhGH therapy decreased successively in the three groups with an increased degree of growth plate fusion, especially when grouped by proximal tibias (GV1-3 mon from 9.38 to 6.08 to 4.56 cm/year, GV4-6 mon from 6.75 to 4.92 to 3.25 cm/year, and height gain from 4.03 to 2.75 to 1.95 cm, all P < 0.001). Moreover, the MRI stages of growth plates independently served as a significant variable for GV and height gain after therapy, especially when grouped by proximal tibias (all P < 0.01). CONCLUSION: The MRI staging method is expected to be an effective tool for predicting rhGH response before therapy initiation in short-stature children in late puberty.

[Pollution Characteristics and Sensitivity of Surface Ozone in a Typical Heavy-Industry City of the North China Plain in Summer].

The pollution characteristics of surface ozone and its response to meteorological factors and precursors were studied based on monitoring and Model-3/CMAQ modeling from May to August 2018 in Handan City, China. The monitoring results showed that the maximum daily 8-hour average ozone concentration (MDA8 O3) ranged from 38.0-238.0 µg·m-3, and the nonattainment for ozone reached 44.7% during the studied period, indicating the more severe photochemical pollution in summer in Handan City. The ozone concentration was positively correlated with temperature (R=0.74 on nonattainment days and 0.42 on attainment days), but negatively correlated with relative humidity (R=-0.63 on nonattainment days and -0.58 on attainment days), demonstrating the role of photochemistry in the surface ozone of Handan City. Moreover, the highest ozone level occurred at wind speeds higher than 2.25 m·s-1 or lower than 1.00 m·s-1 during ozone nonattainment days, which indicated that regional transport and local accumulation can both cause serious ozone pollution in the city. Regarding the response of ozone to its precursors (VOCs and NOx), model simulation results based on the brute force method showed the stronger positive sensitivity to VOCs, but a weak negative sensitivity to NOx. Therefore, reduction of anthropogenic VOCs emissions is the key to improving ozone pollution in Handan City. We used the propylene-equivalent method to identify the importance of alkene and aromatic species for ozone pollution during ozone nonattainment days.

Complete Sequence of a Novel IncR-F33:A-:B- Plasmid, pKP1034, Harboring fosA3, blaKPC-2, blaCTX-M-65, blaSHV-12, and rmtB from an Epidemic Klebsiella pneumoniae Sequence Type 11 Strain in China.

A high fosfomycin resistance rate was observed in Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) in our previous study, but little is known about its mechanisms. In this study, we explored the prevalence of plasmid-mediated fosfomycin resistance determinants among fosfomycin-resistant KPC-KP strains from a Chinese university hospital and determined the complete sequence of a novel fosA3-carrying plasmid isolated from an epidemic K. pneumoniae sequence type (ST) 11 strain. A total of 97 KPC-KP strains were studied, of which 57 (58.8%) were resistant to fosfomycin, including 44 (45.4%) harboring fosA3 and 1 harboring fosA. All fosA3-positive strains belonged to the dominant ST11-pulse type (PT) A clone according to multilocus sequence typing and pulsed-field gel electrophoresis, suggesting clonal dissemination. The fosA-positive isolate belonged to ST11-PTE. The fosA3-carrying plasmid pKP1034 is 136,848 bp in length and is not self-transmissible. It is a multireplicon plasmid belonging to IncR-F33:A-: B-. Besides fosA3, a variety of other resistance determinants, including blaKPC-2, rmtB, blaCTX-M-65, and blaSHV-12, are identified in pKP1034, which would allow for coselection of fosA3 by most ß-lactams and/or aminoglycosides and facilitate its dissemination despite limited use of fosfomycin in China. Detailed comparisons with related plasmids revealed that pKP1034 is highly mosaic and might have evolved from alarming recombination of the blaKPC-2-carrying plasmid pKPC-LK30 from Taiwan and the epidemic fosA3-carrying plasmid pHN7A8 from mainland China.

[Surgical treatment for incomplete Tessier No.3 craniofacial cleft: report of three cases and review of literature].

OBJECTIVE: To primarily assess the surgical technique to correct incomplete Tessier No. 3 craniofacial cleft. METHODS: From 2009 to 2010, 3 male patients with incomplete Tessier No. 3 craniofacial clefts were treated. Preoperative CT examination of each patient was performed and the bony defect was evaluated. In the operation, van der Meulen rotation and advancement flap of the cheek and regional Z-plasty were used and the medial canthal ligament was repositioned. RESULTS: One week after the operation, the sutures were removed and the facial incision healed well. The facial scar was not obvious 6 - 10 months after operation. The shape of medial canthal angle was acceptable, and the height of the medial canthal angle and the length of the palpebral fissure of both sides were symmetrical. The clinical results were satisfactory. CONCLUSIONS: For the incomplete Tessier No. 3 craniofacial cleft, surgical treatment is mainly focused on the deformities of inner canthus and nasal alae. Medial canthal ligament reposition is the key procedure for correction of the medial canthal deformity and surgical results are stable and reliable.

[Division of flap in cleft palate patients after posterior pharyngeal flap surgery].

OBJECTIVE: To investigate the reasons of flap division in patients with posterior pharyngeal flap and the outcome of the flap division for treating secondary velopharyngeal insufficiency (VPI) and obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: Twenty patients who underwent flap division after posterior pharyngeal flap surgery were included in this study, including 11 incomplete cleft palate and 9 complete cleft palate). Nasal endoscopy and lateral cephalometric radiographs were performed for all the patients preoperatively. Speech recordings were made pre- and post-operatively. The respiratory status of patients who had OSAHS manifestations was monitored by polysomnography. Simple division of the flap was carried out in 14 cases, and additional pharyngoplasty combined the division of posterior pharyngeal flap was performed in six cases. RESULTS: The speech did not show significant improvement in 14 cases after posterior pharyngeal flap surgery but improved after flap division. Three cases got speech improvement, but developed the respiratory obstruction causing sleep apnea. After the division of flap, the respiratory status got improved. Three cases required orthognathic surgery under general anesthesia, which demanded the division of flap simultaneously. The speech did not change after the division. CONCLUSIONS: If OSAHS occurred or VPI remained after posterior pharyngeal flap surgery, the division of the flap or additional pharyngoplasty should be performed. It is suggested that the operation of the flap division be done six months after posterior pharyngeal flap surgery.

[Application of computer aided design and rapid prototyping technology for defected maxilla restoration].

OBJECTIVE: To test a new cast-making method based on computer aided design (CAD) and rapid prototyping (RP) technology for defected maxilla. METHODS: Head CT data of 12 patients with defected maxilla were transmitted into a computer. Three-dimensional digital image of the patient's defected maxilla was then obtained based on Mimics 8.11 and Geomagic 7.0 and the plastic cast of the defected region was manufactured by prototyping. The obturator was made on this plastic cast that duplicated the undercut tissue of defected area. The prominent part of the obturator was made of elastic heat-curing resin and it was helpful to gain the retention through the engagement between the obturator and the tissue undercut. After the obturator was finished, the upper removable partial denture was fabricated in conventional method. The combination of these two parts was achieved using magnetic attachment. Clinical effects of obturator and removable partial denture were evaluated and the nasalance value of 5 patients before and after insertion of the obturator was measured using nanometer. RESULTS: The obturator and removable partial denture could be seated into place separately. They all had good retention and stability. After the obturator was seated in place, the nasalance of non-nasal and vowel text decreased from (46.53 +/- 13.86)% to (22.60 +/- 8.52)% (P < 0.001). CONCLUSIONS: The cast-making method based on CAD and RP technology for cast-making of defected maxilla is feasible and practical.

Effect of Zn7-metallothionein on oxidative stress in liver of rats with severe thermal injury.

AIM: Using the model of burned animal with delayed resuscitation to study antagonistic effect of Zn7-metallothionein (Zn7-MT) on oxidative stress in the liver of rats suffered from severe thermal injury on skin. METHODS: To compare the changes in antioxidant concentrations and antioxidative enzyme activities in the liver or plasma of burned rats with or without Zn7-MT in resuscitation fluid by biochemical assay. RESULTS: After injury, glutathione concentration was progressively decreased with time. At 24 h after injury, activities of glutathione reductase and glutathione peroxidase in the liver of burned rats were increased and then decreased at 48 h postburn. Alpha-tocopherol in plasma was reduced at 24 h and malondialdehyde in the liver was increased significantly postburn. MT and MT-1 mRNA expression in burned rats were activated. Taken together, oxidative stress in the liver of burned rats occurred. Exogenous Zn7-MT attenuated the changes in antioxidant concentrations and antioxidative enzyme activities in the liver or plasma of burned rats. The effect of Zn7-MT was in a concentration-dependent manner and the concentration of 10 micromol/L was the most effective. Exogenous Zn7-MT also inhibited MT-1 mRNA overexpression and increased MT protein concentration. CONCLUSION: Zn7-MT effectively antagonized oxidative stress in the liver of rats with severe thermal injury.