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SAGES and EAES recommendations for minimally invasive surgery during COVID-19 pandemic

Francis, Nader; Dort, Jonathan; Cho, Eugene; Feldman, Liane; Keller, Deborah; Lim, Rob; Mikami, Dean; Phillips, Edward; Spaniolas, Konstantinos; Tsuda, Shawn; Wasco, Kevin; Arulampalam, Tan; Sheraz, Markar; Morales, Salvador; Pietrabissa, Andrea; Asbun, Horacio; Pryor, Aurora
The unprecedented pandemic of COVID-19 has impacted many lives and affects the whole healthcare systems globally. In addition to the considerable workload challenges, surgeons are faced with a number of uncertainties regarding their own safety, practice, and overall patient care. This guide has been drafted at short notice to advise on specific issues related to surgical service provision and the safety of minimally invasive surgery during the COVID-19 pandemic. Although laparoscopy can theoretically lead to aerosolization of blood borne viruses, there is no evidence available to confirm this is the case with COVID-19. The ultimate decision on the approach should be made after considering the proven benefits of laparoscopic techniques versus the potential theoretical risks of aerosolization. Nevertheless, erring on the side of safety would warrant treating the coronavirus as exhibiting similar aerosolization properties and all members of the OR staff should use personal protective equipment (PPE) in all surgical procedures during the pandemic regardless of known or suspected COVID status. Pneumoperitoneum should be safely evacuated via a filtration system before closure, trocar removal, specimen extraction, or conversion to open. All emergent endoscopic procedures performed during the pandemic should be considered as high risk and PPE must be used by all endoscopy staff.
PMCID:7175828
PMID: 32323016
ISSN: 1432-2218
CID: 4436782

Incidence of secondary midface advancement at the time of skeletal maturity in patients with a History of Early LeFort III Distraction Osteogenesis [Meeting Abstract]

Cho, G; Borab, Z; Gibson, T; Shetye, P; Grayson, B; Flores, R; McCarthy, J
Background/Purpose: LeFort III distraction osteogenesis is commonly recommended for children with syndromic craniosynostosis to reduce exorbitism, improve airway function, and decrease dysmorphism. This purpose of this study is to report on the long-term clinical outcomes of patients with syndromic craniosynostosis patients who have undergone early primary subcranial LeFort III distraction osteogenesis and who have been followed longitudinally through skeletal maturity. Methods/Description: Retrospective review of all patients who underwent LeFort III distraction osteogenesis between the ages of 3 and 11 years and were followed throughout development with longitudinal dental, medical, radiographic, and photographic evaluations conducted through skeletal maturity and beyond. Inclusion criteria entailed having preoperative medical photographs and cephalometric studies at 6 months and 1, 5, and 10 years postoperatively after the primary LeFort III distraction osteogenesis as well as cephalometric documentation 6 months and 1 year after the secondary midface advancement after skeletal maturity.
Result(s): Seventeen patients fulfilled inclusion criteria, with a mean age of 5.7 years at the time of initial LeFort III distraction. The mean advancement of point A was 14.9 mm anteriorly and 2.7 mm inferiorly along the x- and y-axis, respectively. Orbitale moved 10.5 mm anteriorly and 2.2 mm inferiorly along the x- and y-axis, respectively. At 10 years postoperatively, point A moved 3.4 mm anterior along the xaxis and 4.7 mm inferiorly along the y-axis, while orbitale moved 0.4 mm posteriorly and 3 mm inferiorly along the x- and y-axis, respectively. At the time of skeletal maturity, there was a return of occlusal disharmony from normal mandibular growth and a return of proptosis owing to remodeling of orbitale inferiorly, and the lateral orbital rim posteriorly, while the globe continued to grow in the anterior vector. All but 1 study patient underwent or is scheduled to undergo a secondary midface advancement at the LeFort III and LeFort I level after skeletal maturity was attained.
Conclusion(s): The data demonstrate that patients who undergo early LeFort III distraction osteogenesis before the age of mixed dentition will still most likely need a secondary midface advancement after skeletal maturity is reached given that there is a small degree of anterior growth at the level of the maxilla and no anterior growth at orbitale over time
EMBASE:629011081
ISSN: 1545-1569
CID: 4051502

Apparent diffusion coefficient in estrogen receptor-positive and lymph node-negative invasive breast cancers at 3.0T DW-MRI: A potential predictor for an oncotype Dx test recurrence score

Thakur, Sunitha B; Durando, Manuela; Milans, Soledad; Cho, Gene Y; Gennaro, Lucas; Sutton, Elizabeth J; Giri, Dilip; Morris, Elizabeth A
PURPOSE: To measure the apparent diffusion coefficient (ADC) values in estrogen receptor-positive (ER+) and axillary lymph node-negative (LN-) invasive breast cancer and investigate the correlation of ADC with Oncotype Dx test recurrence scores (ODxRS). MATERIALS AND METHODS: This was a Health Insurance Portability and Accountability Act (HIPAA)-compliant single-site retrospective study. Patients underwent preoperative 3.0T MRI scans with additional diffusion-weighted imaging sequential scans (b = 0, 600 and b = 0, 1000 s/mm2 ) from January 2011 to 2013. The study population included 31 ER+/LN- invasive breast cancers, which underwent ODxRS genomic testing. ADC600 and ADC1000 parametric maps were generated, and ADC values were calculated from a user-drawn region of interest. ODxRS predicts 10-year recurrence risk in individual patients: low (RS <18), intermediate (RS: 18-30), or high (RS >30). All breast lesions, including subgroups of invasive ductal carcinoma (IDC) lesions and mass-only lesions were dichotomized by RS scores, low-risk versus intermediate/high-risk, and statistical analysis was performed using Mann-Whitney's test (statistical significance at P < 0.05) and receiver operating characteristic (ROC) curves. Multivariate analysis was also performed. RESULTS: Invasive breast cancers, when scored as low-risk by ODxRS, had significantly higher ADC values compared with intermediate/high-risk lesions for both ADC600 (P = 0.007) and ADC1000 (P = 0.008) mean values. This was true both when analyzing only mass-lesions (P = 0.03 and 0.01) or only IDCs (P = 0.001 and 0.009). CONCLUSION: Preliminary findings suggest that lesion ADC values correlate with recurrence risk likelihood stratified using ODxRS. Hence, ADC is a potential surrogate biomarker for tumor aggressiveness. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2017.
PMCID:5741548
PMID: 28640531
ISSN: 1522-2586
CID: 2604422

Voxelwise analysis of simultaneously acquired and spatially correlated 18 F-fluorodeoxyglucose (FDG)-PET and intravoxel incoherent motion metrics in breast cancer

Ostenson, Jason; Pujara, Akshat C; Mikheev, Artem; Moy, Linda; Kim, Sungheon G; Melsaether, Amy N; Jhaveri, Komal; Adams, Sylvia; Faul, David; Glielmi, Christopher; Geppert, Christian; Feiweier, Thorsten; Jackson, Kimberly; Cho, Gene Y; Boada, Fernando E; Sigmund, Eric E
PURPOSE: Diffusion-weighted imaging (DWI) and 18 F-fluorodeoxyglucose-positron emission tomography (18 F-FDG-PET) independently correlate with malignancy in breast cancer, but the relationship between their structural and metabolic metrics is not completely understood. This study spatially correlates diffusion, perfusion, and glucose avidity in breast cancer with simultaneous PET/MR imaging and compares correlations with clinical prognostics. METHODS: In this Health Insurance Portability and Accountability Act-compliant prospective study, with written informed consent and approval of the institutional review board and using simultaneously acquired FDG-PET and DWI, tissue diffusion (Dt ), and perfusion fraction (fp ) from intravoxel incoherent motion (IVIM) analysis were registered to FDG-PET within 14 locally advanced breast cancers. Lesions were analyzed using 2D histograms and correlation coefficients between Dt , fp , and standardized uptake value (SUV). Correlations were compared with prognostics from biopsy, metastatic burden from whole-body PET, and treatment history. RESULTS: SUV||Dt correlation coefficient significantly distinguished treated (0.11 +/- 0.24) from nontreated (-0.33 +/- 0.26) patients (P = 0.005). SUV||fp correlations were on average negative for the whole cohort (-0.17 +/- 0.13). CONCLUSION: Simultaneously acquired and registered FDG-PET/DWI allowed quantifiable descriptions of breast cancer microenvironments that may provide a framework for monitoring and predicting response to treatment. Magn Reson Med, 2016. (c) 2016 International Society for Magnetic Resonance in Medicine.
PMCID:5405014
PMID: 27779790
ISSN: 1522-2594
CID: 2288692

Stimulated echo diffusion tensor imaging (STEAM-DTI) with varying diffusion times as a probe of breast tissue

Teruel, Jose R; Cho, Gene Y; Moccaldi Rt, Melanie; Goa, Pal E; Bathen, Tone F; Feiweier, Thorsten; Kim, Sungheon G; Moy, Linda; Sigmund, Eric E
PURPOSE: To explore the application of diffusion tensor imaging (DTI) for breast tissue and breast pathologies using a stimulated-echo acquisition mode (STEAM) with variable diffusion times. MATERIALS AND METHODS: In this Health Insurance Portability and Accountability Act-compliant study, approved by the local institutional review board, eight patients and six healthy volunteers underwent an MRI examination at 3 Tesla including STEAM-DTI with several diffusion times ranging from 68.5 to 902.5 ms. A DTI model was fitted to the data for each diffusion time, and parametric maps of mean diffusivity, fractional anisotropy, axial diffusivity, and radial diffusivity were computed for healthy fibroglandular tissue (FGT) and lesions. The median value of radial diffusivity for FGT was fitted to a linear decay to obtain an estimation of the surface-to-volume ratio, from which the radial diameter was calculated. RESULTS: For healthy FGT, radial diffusivity presented a linear decay with the square root of the diffusion time resulting in a range of estimated radial diameters from 202 to 496 microm, while axial diffusivity presented a nearly time-independent diffusion. Residual fat signal was reduced at longer diffusion times due to the shorter T1 of fat. Residual fat signal to the overall signal in the healthy volunteers' FGT was found to range from 2.39% to 2.55% (shortest mixing time), and from 0.40% to 0.51% (longest mixing time) for the b500 images. CONCLUSION: The use of variable diffusion times may provide an in vivo noninvasive tool to probe diffusion lengths in breast tissue and breast pathology, and might aid by improving fat suppression at longer diffusion times. J. Magn. Reson. Imaging 2016.
PMID: 27441890
ISSN: 1522-2586
CID: 2185552

Intravoxel incoherent motion (IVIM) histogram biomarkers for prediction of neoadjuvant treatment response in breast cancer patients

Cho, Gene Y; Gennaro, Lucas; Sutton, Elizabeth J; Zabor, Emily C; Zhang, Zhigang; Giri, Dilip; Moy, Linda; Sodickson, Daniel K; Morris, Elizabeth A; Sigmund, Eric E; Thakur, Sunitha B
OBJECTIVE: To examine the prognostic capabilities of intravoxel incoherent motion (IVIM) metrics and their ability to predict response to neoadjuvant treatment (NAT). Additionally, to observe changes in IVIM metrics between pre- and post-treatment MRI. METHODS: This IRB-approved, HIPAA-compliant retrospective study observed 31 breast cancer patients (32 lesions). Patients underwent standard bilateral breast MRI along with diffusion-weighted imaging before and after NAT. Six patients underwent an additional IVIM-MRI scan 12-14 weeks after initial scan and 2 cycles of treatment. In addition to apparent diffusion coefficients (ADC) from monoexponential decay, IVIM mean values (tissue diffusivity Dt, perfusion fraction fp, and pseudodiffusivity Dp) and histogram metrics were derived using a biexponential model. An additional filter identified voxels of highly vascular tumor tissue (VTT), excluding necrotic or normal tissue. Clinical data include histology of biopsy and clinical response to treatment through RECIST assessment. Comparisons of treatment response were made using Wilcoxon rank-sum tests. RESULTS: Average, kurtosis, and skewness of pseudodiffusion Dp significantly differentiated RECIST responders from nonresponders. ADC and Dt values generally increased ( approximately 70%) and VTT% values generally decreased ( approximately 20%) post-treatment. CONCLUSION: Dp metrics showed prognostic capabilities; slow and heterogeneous pseudodiffusion offer poor prognosis. Baseline ADC/Dt parameters were not significant predictors of response. This work suggests that IVIM mean values and heterogeneity metrics may have prognostic value in the setting of breast cancer NAT.
PMCID:5565789
PMID: 28856177
ISSN: 2352-0477
CID: 2678922

A method for safety testing of radiofrequency/microwave-emitting devices using MRI

Alon, Leeor; Cho, Gene Y; Yang, Xing; Sodickson, Daniel K; Deniz, Cem M
PURPOSE: Strict regulations are imposed on the amount of radiofrequency (RF) energy that devices can emit to prevent excessive deposition of RF energy into the body. In this study, we investigated the application of MR temperature mapping and 10-g average specific absorption rate (SAR) computation for safety evaluation of RF-emitting devices. METHODS: Quantification of the RF power deposition was shown for an MRI-compatible dipole antenna and a non-MRI-compatible mobile phone via phantom temperature change measurements. Validation of the MR temperature mapping method was demonstrated by comparison with physical temperature measurements and electromagnetic field simulations. MR temperature measurements alongside physical property measurements were used to reconstruct 10-g average SAR. RESULTS: The maximum temperature change for a dipole antenna and the maximum 10-g average SAR were 1.83 degrees C and 12.4 W/kg, respectively, for simulations and 1.73 degrees C and 11.9 W/kg, respectively, for experiments. The difference between MR and probe thermometry was <0.15 degrees C. The maximum temperature change and the maximum 10-g average SAR for a cell phone radiating at maximum output for 15 min was 1.7 degrees C and 0.54 W/kg, respectively. CONCLUSION: Information acquired using MR temperature mapping and thermal property measurements can assess RF/microwave safety with high resolution and fidelity. Magn Reson Med, 2014. (c) 2014 Wiley Periodicals, Inc.
PMCID:4442746
PMID: 25424724
ISSN: 0740-3194
CID: 1359712

Dynamic diffusion-tensor measurements in muscle tissue using the single-line multiple-echo diffusion-tensor acquisition technique at 3T

Baete, Steven H; Cho, Gene Y; Sigmund, Eric E
When diffusion biomarkers display transient changes, i.e. in muscle following exercise, traditional diffusion-tensor imaging (DTI) methods lack the temporal resolution to resolve the dynamics. This article presents an MRI method for dynamic diffusion-tensor acquisitions on a clinical 3T scanner. This method, the Single-Line Multiple-Echo Diffusion-Tensor Acquisition Technique (SL-MEDITATE), achieves a high temporal resolution (4 s) by rapid diffusion encoding through the acquisition of multiple echoes with unique diffusion sensitization and limiting the readout to a single line volume. The method is demonstrated in a rotating anisotropic phantom, a flow phantom with adjustable flow speed and in vivo skeletal calf muscle of healthy volunteers following a plantar flexion exercise. The rotating and flow-varying phantom experiments show that SL-MEDITATE correctly identifies the rotation of the first diffusion eigenvector and the changes in diffusion-tensor parameter magnitudes, respectively. Immediately following exercise, the in vivo mean diffusivity (MD) time courses show, before the well-known increase, an initial decrease that is not typically observed in traditional DTI. In conclusion, SL-MEDITATE can be used to capture transient changes in tissue anisotropy in a single line. Future progress might allow for dynamic DTI when combined with appropriate k-space trajectories and compressed sensing reconstruction
PMCID:4433040
PMID: 25900166
ISSN: 1099-1492
CID: 1543372

Multiple-echo diffusion tensor acquisition technique (MEDITATE) on a 3T clinical scanner

Baete, Steven H; Cho, Gene; Sigmund, Eric E
This article describes the concepts and implementation of an MRI method, the multiple-echo diffusion tensor acquisition technique (MEDITATE), which is capable of acquiring apparent diffusion tensor maps in two scans on a 3T clinical scanner. In each MEDITATE scan, a set of RF pulses generates multiple echoes, the amplitudes of which are diffusion weighted in both magnitude and direction by a pattern of diffusion gradients. As a result, two scans acquired with different diffusion weighting strengths suffice for accurate estimation of diffusion tensor imaging (DTI) parameters. The MEDITATE variation presented here expands previous MEDITATE approaches to adapt to the clinical scanner platform, such as exploiting longitudinal magnetization storage to reduce T2 weighting. Fully segmented multi-shot Cartesian encoding is used for image encoding. MEDITATE was tested on isotropic (agar gel), anisotropic diffusion phantoms (asparagus) and in vivo skeletal muscle in healthy volunteers with cardiac gating. Comparisons of accuracy were performed with standard twice-refocused spin echo (TRSE) DTI in each case and good quantitative agreement was found between diffusion eigenvalues, mean diffusivity and fractional anisotropy derived from TRSE DTI and from the MEDITATE sequence. Orientation patterns were correctly reproduced in both isotropic and anisotropic phantoms, and approximately for in vivo imaging. This illustrates that the MEDITATE method of compressed diffusion encoding is feasible on the clinical scanner platform. With future development and employment of appropriate view-sharing image encoding, this technique may be used in clinical applications requiring time-sensitive acquisition of DTI parameters such as dynamical DTI in muscle
PMCID:3800503
PMID: 23828606
ISSN: 0952-3480
CID: 586182

RF-emission device safety testing using MRI

Alon, L; Cho, GY; Yang, X; Zhu, Y; Sodickson, DK; Deniz, CM
Radiofrequency (RF) emitting wireless devices such as mobile phones are required to undergo standardized safety testing prior to entering the consumer market. Strict regulations are imposed on the amount of RF energy these devices are allowed to emit to prevent excessive deposition of RF energy into the body. In this work, a novel safety evaluation test for wireless devices using magnetic resonance thermometry is proposed.
SCOPUS:84894165647
ISSN: 1522-3965
CID: 843672