Feasibility and utility of intraoperative optical coherence tomography during vitreoretinal surgery:A 4-year report in Chinese population

The objective is to introduce the application of intraoperative optical coherence tomography(iOCT)in pars plana vitrectomy(PPV)for various vitreoretinal diseases,and to report the 4-year assessment of feasibility and utility in Chinese population.We reported a retrospective case series of patients who underwent PPV and iOCT scan at Eye Hospital of Wenzhou Medical University from January 2016 to January 2020.Clinical characteristics were documented before operation,and we intraoperatively recorded the time and results of iOCT scanning,specific surgical maneuvers performed,the consistency with the planned strategies before surgery,the type of OCT images obtained,and adverse events(AEs).The surgeon feedback was collected to evaluate the utility of iOCT during surgery.In total 339 eyes successfully completed iOCT scan,with an average scanning time of 3.54±2.3 min,including 59 cases of idiopathic macular hole(iMH),134 cases of idiopathic epiretinal membrane(iERM),33 cases of lamellar macular hole(LMH),40 cases of high myopic maculopathy,13 cases of vitreous macular traction(VMT),60 cases of dense vitreous hemorrhage(VH).The iOCT findings were not consistent with exami-nation under the operating microscope in 49 cases(14.5%),including 29 cases(8.6%)which changed the operation strategies during surgery.The Hole-door phenomenon arose in 20 cases(33.9%)of iMH and 3 cases(25%)of high myopic MH after ILMs peeling.Moreover,the residue ERM was observed in nine cases(6.7%)of iERM and two cases(14.3%)in high myopic ERM after ILMs peeling.Some new surgical methods could also be confirmed using iOCT.The ap-plication of iOCT has a significant clinical functionality in vitreoretinal surgery,providing the surgeon with a new surgical understanding,guiding the selection of a more reasonable operative procedure during surgery,predicting postoperative recovery and improving postoperative outcomes.

MICROENDOSCOPIC SPECTRAL IMAGING AS A TOOL FOR SMALL DUCTUAL DIAGNOSTICS:PRELIMINARY EXPERIENCE

A technical feasibility of autofluorescence ductoscopy in breast milk ducts as blood vessels phantoms has been assessed as successful.Malignant tumor can be clearly identified through the milk ducts.We also present the operation principle as well as the preliminary experimental results of a new type of microsize multicorefiber that enables imaging through blood vessel phantoms.Imaging of a manipulated microwire through a drilled phantom is presented.

LIMITATIONS OF CANCER MARGIN DELINEATION BY MEANS OF AUTOFLUORESCENCE IMAGING UNDER CONDITIONS OF LASER SURGERY

Limitations of cancer margin delineation and surgical guidance by means of autofluorescence imaging under conditions of laser ablation were investigated and preliminary results are presented.PinPoint^(TM)(Novadaq Technologies Inc.,Canada)was used to capture digital images and Er:YAG laser(2.94μm,Glissando,WaveLight^(TM),Germany)was exploited to cause laser ablation on both normal and cancer sites of the specimen.It was shown that changes of the autofluorescence image after ablation extend beyond the actual sizes of the ablation loci.The tumor tissue after the laser ablation starts to emit fluorescent light within the green wavelength band(490-550nm)similar to normal tissue stating that the current technology of in-process tissue classification fails.However,when the autofluorescence was collected in the red range(600-750nm),then the abnormal/normal contrast was reduced,but still present even after the laser ablation.The present study highlights the importance of finding a proper technology for surgical navigation of cancer removal under conditions of high power effects in biological tissues.

Imaging for thinned perforator flap harvest:current status and future perspectives

With advances in anatomical knowledge and technology,increased interest has been directed towards reconstruction with enhanced aesthetic and functional outcomes.A myriad of thinned perforator flap harvest approaches have been developed for this purpose;however,concerns about jeopardizing their vascularity remain.To ensure optimum reconstructive outcome without hampering the flap’s microcirculation,it is important to make good use of the existing advanced imaging modalities that can provide clear visualization of perforator branches,particularly in the adipose layer,and an accurate assessment of flap perfusion.Therefore,this review will highlight the imaging modalities that have been utilized for harvesting a thinned perforator flap from these two perspectives,along with future insights into creating both functionally and aesthetically satisfying,yet simultaneously safe,thinned perforator flaps for the best reconstructive outcomes for patients.