The fate of unrepaired chronic type A aortic dissection

OBJECTIVES

The current guidelines do not consider chronic type A aortic dissection as one of the triggers for prophylactic aortic repair, and an aortic diameter of 55 mm is considered the threshold for surgery.

METHODS

From the institutional database, we retrieved 82 patients who were diagnosed as having chronic type A aortic dissection but did not undergo immediate surgical repair from 1997 to 2016. The primary outcome was a composite of adverse aortic events defined as aortic rupture and sudden death. Conversion to elective surgery during follow-up was regarded as competing risk for adverse events.

RESULTS

The median value of the maximal aortic diameter at baseline was 55.2 mm. During a median follow-up of 77.1 months, 19 adverse events occurred while 9 patients received elective aortic repair. On multivariable competing risk analyses, baseline aortic diameter and age emerged as significant and independent factors associated with aortic events. The estimated rates of aortic event within 5 years were 12.0%, 19.4%, and 29.7% for aortic diameters of 50, 60, and 70 mm, respectively, with escalating risk rates as age increased for the given aortic diameters.

CONCLUSIONS

In unrepaired chronic type A aortic dissection, aortic events were not infrequent even for patients with an aortic diameter of less than 55 mm. This finding indicates that there may be a need to lower the surgical threshold for chronic type A aortic dissection.

Safety of medial dissection of the thyroid gland along the trachea based on anatomic constancy of the laryngeal entry point of the recurrent laryngeal nerve

Purpose

The purpose of this study was to determine the extent of safety of medial dissection of the thyroid gland along the trachea. Medial to lateral dissection of the thyroid gland along the trachea after early division of the isthmus has been known to be a useful technique in thyroid surgery, especially for difficult cases, but the risk of injury of the recurrent laryngeal nerve (RLN) has constrained thyroid surgeons from utilizing this technique to its full extent.

Methods

Distances of the laryngeal entry point (LEP) of 134 RLNs of 71 patients from the midline of the trachea, and some other anatomical distances, were measured intraoperatively. The relationships of the intraoperatively measured data with circumferences of the cartilaginous portion of the trachea (CCT) around LEP measured preoperatively by CT scan were evaluated.

Results

LEP was always located within 2 mm vertically from the horizontally extended line of the inferior border of the cricoid cartilage and was the closest point from the midline in the whole course of the RLN. The distance between LEP and the midline was very closely correlated with CCT measured on preoperative CT scan, and it can be accurately calculated with a regression equation; Distance between LEP and the midline = (0.42 × CCT) + (1.2 × sex) + 3.2 (mm) (sex: female=0, male=1; R² = 0.85).

Conclusion

Early division of the isthmus and dissecting the thyroid off the trachea to the calculated extent is a safe and effective procedure.

Tissue adhesive, rapid forming, and sprayable ECM hydrogel via recombinant tyrosinase crosslinking

We report on a tissue adhesive hydrogel based on novel recombinant tyrosinase mediated crosslinking. The adhesive hydrogels were fabricated by the site-directed coupling of tyramine-conjugated hyaluronic acid (HA_t, 1% w/v) and gelatin (3% w/v) (HG_gel) with novel tyrosinase derived from Streptomyces avermitilis (SA_Ty). The enzyme-based crosslinking by SA_Ty was fast, with less than 50 s for complete gelation, and the SA_Ty based crosslinking enhanced the physical properties and adhesive strength of the hydrogel significantly with the native tissue samples. Furthermore, by optimizing the injection conditions, we tailored the enzyme-based crosslinking hydrogels to be injectable and sprayable with a medical syringe and commercial airbrush nozzle, respectively. An in vivo analysis of the adhesive hydrogel showed a negligible immune reaction. In this study, demonstrate that the novel enzyme-based crosslinking hydrogel has a robust potential in tissue engineering and regenerative medicine.

Aortic arch repair under moderate hypothermic circulatory arrest with or without antegrade cerebral perfusion based on the extent of repair

Background

For aortic-arch repair, moderate hypothermic circulatory arrest (HCA) have shown favorable outcomes over conventional deep HCA when coupled with antegrade cerebral perfusion (ACP); however, recent studies have shown that ACP may not be essential when circulatory arrest time is less than 30 minutes. This study aims to evaluate the stratified arch repair strategy of moderate HCA with or without ACP based on the extent of procedure.

Methods

Consecutive 138 patients (63 female; mean age, 60.2±15.7 years) undergoing open arch repair due to acute aortic syndrome (n=69) or chronic aneurysm (n=69) from January 2012 through April 2017 were enrolled in this study. Stratified neuroprotective strategy was employed according to the extent of repair: hemi-arch repair (n=93) was performed under moderated HCA alone and total-arch repair (n=45) under moderate HCA combined with unilateral ACP.

Results

Median total circulatory arrest and total procedural times were 8.0 minutes [interquartile range (IQR), 6.0-10.0] and 233.0 minutes (IQR, 196.0-290.0 minutes), respectively in the hemi-arch group, and 25.0 minutes (IQR, 12.0-33.0 minutes) and 349.0 minutes (IQR, 276.0-406.0 minutes), respectively in the total-arch group. Early mortality occurred in 2 patients (1.4%) who underwent hemi-arch repair for acute aortic dissection. There was no permanent neurological injury, but 2 cases (1.4%) of temporary neurologic deficit in the hemi-arch group. Other complications included re-exploration for bleeding in 6 (4.3%), postoperative extracorporeal life support in 5 (3.6%) and new-dialysis in 6 (4.3%).

Conclusions

Stratified cerebral perfusion strategy using moderate hypothermia for aortic-arch surgery based on the extent of arch repair showed satisfactory safety and reasonable efficiency.

Abstract P4-06-12: Different patterns of risk reducing decisions in affected or unaffected BRCA mutation carriers

BACKGROUND

Risk-reducing (RR) management decreases the risk of breast cancer and BRCA related gynecologic cancer. However, there are fewer reports on the RR management in Asia compared to Western countries.The aim of this study is to identify risk reducing management patterns with BRCA1 or BRCA2 mutation carriers.

METHODS

The study group consisted of all consecutive 1104 breast cancer, ovarian patients and their families of high-risk patients who underwent BRCA gene testing in National Cancer Center, Korea from 2008 to 2016. A total 220 BRCA mutations (19.9%) were detected with 125(11.3%) of BRCA1 gene and 95 (8.6%) of BRCA2 gene.

RESULTS

Out of 220 BRCA mutations carriers, they were consisted of 83 breast cancers, 10 ovarian cancers, 7 both cancers, and 120 unaffected carriers. Among them, 42 were men and 178 were women. About 90 % (198/ 220) had the familial history of breast, ovarian or both malignancies (113 in BRCA1 and 85 in BRCA2 mutation (p=0.821)).

All 42 men chose surveillance. Among 178 female BRCA mutation carriers, 98(55.1%) underwent risk reducing management including 18(10.1%) of chemoprevention, and 80(49.9%) had risk-reducing surgeries (RRSs) (1 case of risk-reducing mastectomy, 76 of risk reducing bilateral salphingo-oophorectomy (RRSO), and 3 of both) and 80 (54.9%) chose only intensive surveillance for both of breast and ovary cancer.

In affected carriers with breast cancer, 59 (71.1%) underwent RR management (1 case of risk reducing mastectomy, 53 of RRSO, 3 of both surgery, and 2 of chemoprevention). There was no risk reducing management in affected carrier with ovarian cancer patients. In 78 unaffected women carriers, 39(50.0%) women received RR management (23(29.5%) cases of RRSO and 16(20.5%) cases of chemoprevention). The rates of RRSs have increased annually since the 2013 year, (prior to 2013 vs. since 2013, RRSs 28.6% (6 cases/21 carriers) vs. 37.2% (74/199), p<0.01).

CONCLUSION

This study was conducted on the largest numbers of BRCA mutation carriers in Asian countries. RRSO is the more preferred management for affected carriers with breast cancer or unaffected carriers. The results might be explained by the severity of the illness and that RRSO was only reimbursed RR strategy from the Korean Government Insurance. Tailored genetic counseling and insurance policy may enhance overall levels of RR management.

Citation Format: Lee EG, Kang H, Park SJ, Han JH, Jung S-Y, Lee S, Kang H-S, Park B, Kong S-Y, Lim MC, Park S-Y, Lee ES. Different patterns of risk reducing decisions in affected or unaffected BRCA mutation carriers [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-06-12.

Macrophage migration inhibitory factor levels correlate with an infection in trauma patients

BACKGROUND

The role of migration inhibitory factor (MIF) is best understood in septic shock and septic disease; however, the role of MIF in a secondary infection after trauma has not yet been completely studied. This study aimed to evaluate the role of MIF in trauma patients.

METHODS

The patients in the study population were divided into two groups according to the results of their MIF levels. The initial MIF levels, trauma mechanism, revised trauma score, survival rate, length of stay (LOS) in the intensive care unit (ICU), level of leukocytes, and level of C-reactive protein (CRP) were compared between the groups.

RESULTS

Overall, 116 patients were enrolled from August 1, 2014 to July 31, 2015. LOS in ICU in the elevated MIF group was 5.67±7.54 days compared with 2.09±2.26 days in the normal MIF group. Further, CRP level in the elevated MIF group was higher than that in the normal MIF group.

CONCLUSION

In a place such as the department of emergency medicine, it is critical and important for emergency physicians to make a proper judgment and to prepare for the worst scenario. Therefore, the utilization of MIF level in trauma patients has a possibility for assisting emergency physicians.

Reliability of histographic analysis for paraspinal muscle degeneration in patients with unilateral back pain using magnetic resonance imaging

BACKGROUND

Mixed use of T1- or T2-weighted magnetic resonance imaging (MRI) in histographic analysis has impeded cross-reference of studies on fatty degeneration of muscles in patients with back pain.

OBJECTIVE

The current study aimed to establish the measurement reliability of histographic analysis for normal and painful paraspinal muscles between T1- and T2-weighted MRI.

METHODS

T1- and T2-weighted MRI at the L4-5 level were performed in 31 patients with unilateral back pain. Two raters conducted the histographic analysis on 2 separate occasions. Multifidus, erector spinae, and psoas major muscles were assessed on both normal and painful sides.

RESULTS

Intra- and interrater reliability of the parameters were generally excellent for both T1- (intrarater: 0.83 ± 0.13 and interrater: 0.93 ± 0.08) and T2-weighted images (intrarater: 0.93 ± 0.12 and interrater: 0.92 ± 0.12). Histogram width was fair to good for both kinds of image. Intraclass correlation coefficients were similar between painful and normal sides.

CONCLUSIONS

The evidence that most histographic analysis parameters had excellent reliability for both T1- and T2-weighted images allows for cross-reference of the results between the two kinds of image. Moreover, the results of this study support the availability of histographic analysis for assessment of fatty degeneration in patients with back pain.

Faucial Pillar Perforation by Glidescope Intubation with Incorrectly Placed Stylet

Glidescope GVL® is frequently used in intubation of difficult airway. We report a case of right side of faucial pillar perforation during intubation with Glidescope®. A rigid stylet can facilitate placing of endotracheal tube quickly but it may also penetrate the soft tissue to cause injuries.

TRIENNIAL GROWTH AND DEVELOPMENT SYMPOSIUM: Molecular mechanisms related to bovine intramuscular fat deposition in the longissimus muscle

The intramuscular fat (IMF) content of the LM, also known as marbling, is particularly important in determining the price of beef in Korea, Japan, and the United States. Deposition of IMF is influenced by both genetic (e.g., breed, gender, and genotype) and nongenetic factors (e.g., castration, nutrition, stressors, animal weight, and age). Castration of bulls markedly increases deposition of IMF, resulting in improved beef quality. Here, we present a comparative gene expression approach between bulls and steers. Transcriptomic and proteomic studies have demonstrated that the combined effects of increases in lipogenesis, fatty acid uptake, and fatty acid esterification and decreased lipolysis are associated with increased IMF deposition in the LM. Several peripheral tissues (LM, adipose tissues, and the liver) are involved in lipid metabolism. Therefore, understanding the significance of the tissue network in lipid metabolism is important. Here, we demonstrate that lipid metabolism in LM tissues is crucial for IMF deposition, whereas lipid metabolism in the liver plays only a minor role. Metabolism of body fat and IMF deposition in bovine species has similarities with these processes in metabolic diseases, such as obesity in humans and rodents. Extensive studies on metabolic diseases using epigenome modification (DNA methylation, histone modification, and microRNA), microbial metagenomics, and metabolomics have been performed in humans and rodents, and new findings have been reported using these technologies. The importance of applying "omics" fields (epigenomics, metagenomics, and metabolomics) to the study of IMF deposition in cattle is described. New information on the molecular mechanisms of IMF deposition may be used to design nutritional or genetic methods to manipulate IMF deposition and to modify fatty acid composition in beef cattle. Applying nutrigenomics could maximize the expression of genetic potential of economically important traits (e.g., marbling) in animals.

Self-spreading of the wetting ridge during stick-slip on a viscoelastic surface

Dynamic wetting behaviors on soft solids are important to interpret complex biological processes from cell-substrate interactions. Despite intensive research studies over the past half-century, the underlying mechanisms of spreading behaviors are not clearly understood. The most interesting feature of wetting on soft matter is the formation of a "wetting ridge", a surface deformation by a competition between elasticity and capillarity. Dynamics of the wetting ridge formed at the three-phase contact line underlies the dynamic wetting behaviors, but remains largely unexplored mostly due to limitations in indirect observation. Here, we directly visualize wetting ridge dynamics during continuous- and stick-slip motions on a viscoelastic surface using X-ray microscopy. Strikingly, we discover that the ridge spreads spontaneously during stick and triggers contact line depinning (stick-to-slip transition) by changing the ridge geometry which weakens the contact line pinning. Finally, we clarify 'viscoelastic-braking', 'stick-slipping', and 'stick-breaking' spreading behaviors through the ridge dynamics. In stick-breaking, no ridge-spreading occurs and contact line pinning (hysteresis) is enhanced by cusp-bending while preserving a microscopic equilibrium at the ridge tip. We have furthered the understanding of spreading behaviors on soft solids and demonstrated the value of X-ray microscopy in elucidating various dynamic wetting behaviors on soft solids as well as puzzling biological issues.

Robotic Cholecystectomy Using the Newly Developed Korean Robotic Surgical System, Revo-i: A Preclinical Experiment in a Porcine Model

One Korean company recently successfully produced a robotic surgical system prototype called Revo-i (MSR-5000). We, therefore, conducted a preclinical study for robotic cholecystectomy using Revo-i, and this is a report of the first case of robotic cholecystectomy performed using the Revo-i system in a preclinical porcine model. Revo-i consists of a surgeon console (MSRC-5000), operation cart (MSRO-5000) and vision cart (MSRV-5000), and a 40 kg-healthy female porcine was prepared for robotic cholecystectomy with general anesthesia. The primary end point was the safe completion of these procedures using Revo-i: The total operation time was 88 minutes. The dissection time was defined as the time from the initial dissection of the Calot area to the time to complete gallbladder detachment from the liver bed: The dissection time required 14 minutes. The surgical console time was 45 minutes. There was no gallbladder perforation or significant bleeding noted during the procedure. The porcine survived for two weeks postoperatively without any complications. Like the da Vinci surgical system, the Revo-i provides a three-dimensional operative view and allows for angulated instrument motion (forceps, needle-holders, clip-appliers, scissors, bipolar energy, and hook monopolar energy), facilitating an effective laparoscopic procedure. Our experience suggests that robotic cholecystectomy can be safely completed in a porcine model using Revo-i.

Borrelia Species Detected in Ticks Feeding on Wild Korean Water Deer (Hydropotes inermis) Using Molecular and Genotypic Analyses

Lyme borreliosis is a vector-borne disease transmitted through the bite of ticks infected by Borrelia burgdorferi sensu lato group, including B. burgdorferi sensu stricto, B. afzelii, and B. garinii. The goal of the present study was to detect Borrelia species in ticks infesting wild Korean water deer (KWD; Hydropotes inermis Swinhoe), using molecular and genotypic analyses. In total, 48 ticks were collected from KWD, all of which were morphologically identified as Haemaphysalis longicornis Neumann that is dominant in Korea. Nested PCR was performed to detect the Borrelia-specific 5S (rrf)-23S (rrl) intergenic spacer region and the outer surface protein A (ospA) genes in ticks. Both rrf-rrl and ospA were amplified from one of the 48 ticks (2.1%) and were identified as B. afzelii. To our knowledge, this study constitutes the first molecular detection of B. afzelii in Haemaphysalis ticks in Korea. Because B. afzelii is a zoonotic tick-borne pathogen, understanding the molecular characteristics of this bacterium is important for preventing the transmission of Borrelia from ticks to other animals and humans.

Adequate interval for the monitoring of vital signs during endotracheal intubation

Background

In the perioperative period, it may be inappropriate to monitor vital signs during endotracheal intubation using the same interval as during a hemodynamically stable period. The aim of the present study was to determine whether it is appropriate to use the same intervals used during the endotracheal intubation and stable periods to monitor vital signs of patients under general anesthesia.

Methods

The mean arterial pressure (MAP) and heart rate (HR) were continuously measured during endotracheal intubation (15 min after intubation) and hemodynamically stable (15 min before skin incision) periods in 24 general anesthesia patients. Data was considered “unrecognized” when continuously measured values were 30% more or less than the monitored value measured at 5- or 2.5-min intervals. The incidence of unrecognized data during endotracheal intubation was compared to that during the hemodynamically stable period.

Result

There were significantly more unrecognized MAP data measured at 5-min intervals during endotracheal intubation than during the hemodynamically stable period (p value <0.05). However, there was no difference in the incidence of unrecognized MAP data at 2.5 min intervals or HR data at 5 or 2.5 min intervals between during the endotracheal intubation and hemodynamically stable periods.

Conclusion

A 5-min interval throughout the operation period was not appropriate for monitoring vital signs. Therefore, , a 2.5-min interval is recommended for monitoring the MAP during endotracheal intubation.

The application of an acellular dermal allograft (AlloDerm) for patients with insufficient conjunctiva during evisceration and implantation surgery

PurposeTo describe the use of an acellular dermal allograft (AlloDerm) for patients with insufficient conjunctiva during evisceration and implantation surgery.Patients and methodsThe medical records of six patients with insufficient conjunctiva during evisceration surgery were reviewed. It was not possible to close the Tenon's capsule and conjunctiva without wound tension in these patients, so AlloDerm was placed over the sclera, and the edges were sutured with adjacent conjunctiva without tension. The size of the bare AlloDerm graft was measured in all patients. The clinical outcome was the incidence of complications, and the percentage of patients needing additional surgery was also recorded.ResultsThe cause of evisceration was end stage glaucoma (four patients) and endogenous endophthalmitis (two patients). All six eyes of six patients (100%) had a successful outcome showing no complications. Four cases achieved full conjunctivalisation over the bare AlloDerm graft. Two cases had a bare AlloDerm until the last follow-up, but showed no implant exposure. It took a median of 11 weeks for the slow advance of the conjunctival edge to entirely cover the AlloDerm graft.ConclusionsAlloDerm is a promising material for covering sclera and implants in a tension-free manner after evisceration surgery in patients with insufficient conjunctiva.