Ionizing Radiation in Craniofacial Surgery: A Primer on Dose and Risks

Intravital observation of high-scattering and dense-labeling hepatic tissues using multi-photon fluorescence microscopy

Achieving high-resolution and large-depth microscopic imaging in vivo under conditions characterized by high-scattering and dense-labeling, as commonly encountered in the liver, poses a formidable challenge. Here, through the optimization of multi-photon fluorescence excitation window, tailored to the unique optical properties of the liver, intravital microscopic imaging of hepatocytes and hepatic blood vessels with high spatial resolution was attained. It's worth noting that resolution degradation caused by tissue scattering of excitation light was mitigated by accounting for moderate tissue self-absorption. Leveraging high-quality multi-photon fluorescence microscopy, we discerned structural and functional alterations in hepatocytes during drug-induced acute liver failure. Furthermore, a reduction in indocyanine green metabolism rates associated with acute liver failure was observed using NIR-II fluorescence macroscopic imaging.

Enhancing Total Optical Throughput of Microscopy with Deep Learning for Intravital Observation

The significance of performing large-depth dynamic microscopic imaging in vivo for life science research cannot be overstated. However, the optical throughput of the microscope limits the available information per unit of time, i.e., it is difficult to obtain both high spatial and temporal resolution at once. Here, a method is proposed to construct a kind of intravital microscopy with high optical throughput, by making near-infrared-II (NIR-II, 900-1880 nm) wide-field fluorescence microscopy learn from two-photon fluorescence microscopy based on a scale-recurrent network. Using this upgraded NIR-II fluorescence microscope, vessels in the opaque brain of a rodent are reconstructed three-dimensionally. Five-fold axial and thirteen-fold lateral resolution improvements are achieved without sacrificing temporal resolution and light utilization. Also, tiny cerebral vessel dilatations in early acute respiratory failure mice are observed, with this high optical throughput NIR-II microscope at an imaging speed of 30 fps.

Favorable Transverse Maxillary Development after Covering the Lateral Raw Surfaces with Buccal Fat Flaps in Modified Furlow Palatoplasty: A 3D Imaging-Assisted Long-Term Comparative Outcome Study

BACKGROUND

The pedicled buccal fat flap has recently been applied to cover the lateral raw surfaces during palatoplasty as an attempt to mitigate scar-induced transverse maxillary constriction during growth, but with no formal long-term comparative analysis. This 3D imaging-assisted study assessed its impact on posterior transverse maxillary development.

METHODS

Cone beam computerized tomography scans from patients with unilateral cleft lip, alveolus and palate who received buccal fat flap (buccal fat group; n=22) or Surgicel (Surgicel group; n=32) for covering lateral raw surfaces during modified Furlow palatoplasty at 9-10 months old and had reached 9 years old were retrieved for analysis. Patients with unilateral cleft lip and alveolus (non-palatoplasty group; n=24) were also included for comparison. Using 3D maxillary image models, linear (U6T-MSP and U6J-MSP) and area measurements were calculated for cleft and non-cleft posterior maxillary sides as well as for total posterior transverse maxillary dimension.

RESULTS

The buccal fat group had significantly (all p<0.05) wider dimensions compared with the Surgicel group for all transverse maxillary measurements on both the cleft and non-cleft sides, with exception for U6J-MSP and posterior palatal area parameters on the cleft side (p>0.05). The buccal fat group had significantly (all p<0.05) wider total transverse maxillary dimensions compared with Surgicel and non-palatoplasty groups.

CONCLUSION

Covering the lateral raw surfaces with buccal fat flaps resulted in less posterior transverse maxillary constriction compared with the Surgicel-based covering procedure.

Anthropometric cranial measurements in metopic craniosynostosis/trigonocephaly: diagnostic criteria, classification of severity and indications for surgery

ABSTRACT

Metopic craniosynostosis is the second most frequent type of craniosynostosis. When the phenotypic presentation has been deemed severe the treatment is surgical in nature and is performed in infancy with fronto-orbital advancement and cranial vault remodeling. At the time of this writing, there is no consensus regarding an objective evaluation system for severity, diagnostic criteria, or indications for surgery. This study aims to review the anthropometric cranial measurements and the relative diagnostic criteria/classification of severity/surgical indications proposed so far for this skull malformation, and to investigate if there is any scientific support for their utility.

Comparison of an unsupervised machine learning algorithm and surgeon diagnosis in the clinical differentiation of metopic craniosynostosis and benign metopic ridge

Metopic suture closure can manifest as a benign metopic ridge (BMR), a variant of normal, to “true” metopic craniosynostosis (MCS), which is associated with severe trigonocephaly. Currently, there is no gold standard for how much associated orbitofrontal dysmorphology should trigger surgical intervention. In our study, we used three-dimensional (3D) curvature analysis to separate the phenotypes along the spectrum, and to compare surgeons’ thresholds for operation. Three-dimensional curvature analyses on 43 subject patients revealed that the mean curvature of mid-forehead vertical ridge was higher for patients who underwent operation than those who did not undergo operation by 1.3 m⁻¹ (p < 0.0001). In addition, these patients had more retruded supraorbital areas by −16.1 m⁻¹ (p < 0.0001). K-means clustering classified patients into two different severity groups, and with the exception of 2 patients, the algorithm’s classification of deformity completely agreed with the surgeons’ decisions to offer either conservative or operative therapy (i.e. 96% agreement). The described methods are effective in classifying severity of deformity and in our experience closely approximate surgeon therapeutic decision making. These methods offer the possibility to consistently determine when surgical intervention may be beneficial and to avoid unnecessary surgeries on children with benign metopic ridge and associated minimal orbitofrontal deformity.