Enhanced sensitivity in THz plasmonic sensors with silver nanowires

We developed hybrid slot antenna structures for microbial sensing in the THz frequency range, where silver nanowires (AgNWs) were employed to increase the sensitivity. In order to fabricate the hybrid devices, we partially etched the AgNW in the slot antenna region, where we can expect the field enhancement effect at the AgNW tip. We measured the resonant-frequency shift observed upon the deposition of a polymer layer, and observed that the sensitivity increased upon the introduction of AgNWs, with an enhancement factor of more than four times (approximately six times in terms of figure-of-merit). The sensitivity increased with the AgNW density until saturation. In addition, we tested devices with PRD1 viruses, and obtained an enhancement factor of 3.4 for a slot antenna width of 3 μm. Furthermore, we performed finite-difference time-domain simulations, which confirmed the experimental results. The sensitivity enhancement factor decreased with the decrease of the slot width, consistent with the experimental findings. Two-dimensional mapping of the electric field confirmed the strong field localization and enhancement at the AgNW tips.

Sarcopenia is associated with the risk of significant liver fibrosis in metabolically unhealthy subjects with chronic hepatitis B

BACKGROUND

Sarcopenia is significantly associated with the degree of liver fibrosis. This study investigated the influence of sarcopenia on liver fibrosis in individuals with chronic hepatitis B.

METHODS

Data from the Korean National Health and Nutrition Examination Surveys 2008-2011 were analysed. The sarcopenia index (total appendicular skeletal muscle mass [kg]/body mass index [kg/m² ]) was calculated using dual-energy X-ray absorptiometry. Sarcopenia was defined as the lowest quintile sarcopenia index value (cut-offs: 0.89 for men and 0.58 for women). The fibrotic burden was assessed using the nonalcoholic fatty liver disease fibrosis score and fibrosis-4 index. Significant fibrosis was defined as the highest nonalcoholic fatty liver disease fibrosis score quartile and a fibrosis-4 index ≥2.67.

RESULTS

Among the 506 respondents with chronic hepatitis B (258 men and 248 women), the nonalcoholic fatty liver disease fibrosis score and fibrosis-4 index identified sarcopenia and significant fibrosis in 126 (24.9%) and 217 (42.9%), respectively. Sarcopenia was significantly associated with significant fibrosis, regardless of the fibrosis prediction model used (all P < 0.05). When the study population was stratified according to metabolic factors, sarcopenia was specifically associated with an increased risk of significant fibrosis among subgroups with obesity, insulin resistance, metabolic syndrome and liver steatosis (odds ratio 2.37-3.57; all P < 0.05). An independent association between sarcopenia and significant fibrosis was identified after adjusting for other confounders (odds ratio 2.67-3.62 by the nonalcoholic fatty liver disease fibrosis score and 2.04-2.62 by the fibrosis-4 index; all P < 0.05).

CONCLUSIONS

Sarcopenia is associated with significant fibrosis in subjects with chronic hepatitis B, specifically those with obesity, insulin resistance, metabolic syndrome and liver steatosis.

Bronchial angles are associated with nodular bronchiectatic non-tuberculous mycobacteria lung disease

BACKGROUND

The nodular bronchiectatic (NB) form of non-tuberculous mycobacteria (NTM) lung disease usually involves the right middle lobe (RML) and the left upper lobe lingular segment. However, the reason underlying this preference is not known.

METHODS

Fifty patients with NB NTM lung disease who had both positive NTM culture(s) and NB lesions in the RML or lingular segment on computed tomography (CT) of the chest, and 100 healthy subjects matched for sex, age, height and body weight with normal chest CT, were randomly selected. Using reconstructed curved multiplanar reformation (MPR) images, the lengths, diameters and angles of the RML and lingular bronchi were measured.

RESULTS

Of the 150 individuals, 64% were female; the mean age was 55 years. The angles of the bronchi were significantly more acute in patients than in healthy subjects, both in the RML (patients, mean 46.75° ± standard deviation 8.87° vs. healthy subjects, mean 51.73° ± 7.76°; P = 0.001) and in the lingular segments (patients, mean 26.94° ± 8.16° vs. healthy subjects, mean 34.65° ± 9.75°; P < 0.001). In addition, the angles of the bronchi in the involved segments were more acute than those in the non-involved segments, both in the RML and the lingular segments. There were no differences in the lengths and bronchi diameters between groups.

CONCLUSIONS

An acute angle (obtuse slope) of RML/lingular bronchi could be an anatomical risk factor for NB NTM lung disease.

Predictors of failure to detect early hepatocellular carcinoma in patients with chronic hepatitis B who received regular surveillance

BACKGROUND

A proportion of chronic hepatitis B (CHB) patients are diagnosed with advanced hepatocellular carcinoma (HCC) despite regular surveillance.

AIMS

To determine predictors for HCC detection failure in CHB patients who underwent regular surveillance.

METHODS

CHB patients with well-preserved liver function, who underwent ultrasonography and alpha-foetoprotein (AFP) analysis every 6 months, were enrolled. Cox regression analysis was used to identify predictors for detection failure, defined as HCC initially diagnosed at Barcelona Clinic Liver Cancer (BCLC) stage B or C.

RESULTS

Of the 4590 CHB patients (mean age, 52.1 years; men, 61.6%), 169 patients were diagnosed with HCC (3.68%) and 35 (20.7%) HCC patients were initially diagnosed with HCC BCLC stage B or C. The cumulative incidence of HCC detection failure was 0.2% at year 1 and 1.3% at year 5. Multivariate analyses indicated that cirrhosis (hazard ratio [HR], 3.078; 95% CI, 1.389-6.821; P = 0.006), AFP levels ≥9 ng/mL (HR, 5.235; 95% CI, 2.307-11.957; P = 0.010), and diabetes mellitus (HR, 3.336; 95% CI, 1.341-8.296; P = 0.010) were independent predictors of HCC detection failure. Another model that incorporated liver stiffness (LS) values identified LS values ≥11.7 kPa (HR, 11.045; 95% CI, 2.066-59.037; P = 0.005) and AFP levels ≥9 ng/mL (HR, 4.802; 95% CI, 1.613-14.297; P = 0.005) as predictors of detection failure.

CONCLUSIONS

In CHB patients undergoing regular surveillance with ultrasonography and alpha-foetoprotein (AFP) analysis every 6 months, the HCC detection failure rate was not high (0.8% per person; 0.1% per test). However, careful attention should be paid in patients with advanced liver fibrosis (clinical cirrhosis or LS value >11.7 kPa), high AFP levels, or diabetes mellitus, who are prone to surveillance failure.

Abstract P5-22-03: Arm node preserving surgery in primary breast cancer patients : 5 year experience

Background:

Lymphedema is one of the major complications of axillary lymph node dissection (ALND) in patients with breast cancer. Axillary reverse mapping (ARM) is the technique to find lymphatic drainage from the arm during ALND. The purpose of this study is to evaluate the efficacy of arm node preserving surgery using ARM for reducing the incidence of lymphedema after axillary lymph node dissection in breast cancer patients and its oncologic safety.

Methods:

From January 2009 to October 2014, 167 patients with primary breast cancer were included. In all patients, 1 mCi of 99mTc-phytate was injected at the ipsilateral subareolar plexus and for axillary reverse mapping, 2.5mL of methylene blue was injected into the subcutaneous area of the medial intermuscular groove of the ipsilateral upper arm. The injection site was massaged for at least 5 minutes with the arm lifted above the heart level. At least 15 minutes later, ALND was performed and blue-stained arm nodes were identified. Arm nodes that were enlarged, hard or looked suspicious for metastasis were removed and all other arm nodes were preserved. Arm circumference at 10cm proximal to the medial epicondyle were measured pre- and post-operatively for 2 years. Circumference difference between both upper arms (CD) was evaluated and lymphedema was defined as CD of ≥ 2cm. Follow-up studies were performed every 6 months for 5 years and then annually using mammography, ultrasonography, and/or positron emission tomography.

Results:

Among 167 patients, 125 patients (74.9%) had their arm node preserved (ANP) and 42 (25.1%) patients had their arm node removed (ANR). Statistically significant difference in the mean number of harvested nodes was observed between ANP group (17.85±6.74) and ANR group (20.17±6.08) (p=0.05). The mean number of total identified blue stained arm nodes were 1.35±0.84. The mean follow-up period for measurement of arm circumference was 16.62±8.36 months. The last measured CD between both upper arms was 0.19±0.67cm in ANP group and 0.67±0.92cm in ANP group (p=0.003). 20 patients complained subjective symptoms of lymphedema, 7 patients in ANP group and 13 patients in ANR group (5.6% vs 31%, p&lt;0.001). Among them, one patient in ANP group and 6 patients in ANR group were diagnosed with lymphedema ( 0.8% vs 14.3%, p=0.001). The other 13 patients' CDs between both upper arms were below objective criteria of lymphedema. Follow-up studies were performed for 59.4±22.40 months. There were 16 cases of distant metastasis, 12 cases in ANP group, 4 cases in ANR group (9.6% vs 9.5%, p=1). Two patients in ANP group had distant metastasis and ipsilateral axillary recurrence simultaneously, but their TNM stages were already IIIc and IIb at the diagnosis. There's no solitary axillary recurrence.

Conclusion:

Arm node preserving surgery using axillary reverse mapping in breast cancer patients can reduce the incidence of lymphedema after axillary lymph node dissection and it simultaneously has oncologic safety.

Citation Format: Park JY, Choi JE, Bae YK, Lee SJ. Arm node preserving surgery in primary breast cancer patients : 5 year experience [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 P5-22-03.

Efficacy of the Perfluoro-N-Octane-Assisted Single-Layered Inverted Internal Limiting Membrane Flap Technique for Large Macular Holes

PURPOSE

The aim of this study was to evaluate the efficacy of the perfluoro-n-octane-assisted single-layered inverted internal limiting membrane (ILM) flap for large macular holes (MHs).

METHODS

We reviewed idiopathic MHs >400 μm. The patients were divided into ILM peeling (group P, 51 eyes) and ILM flap (group F, 41 eyes). Closure of MHs, best-corrected visual acuity (BCVA), and postoperative optical coherence tomography findings were analyzed.

RESULTS

MH closure was achieved in 88.2% in group P and in 100% in group F (p = 0.032). SF6 and air was used most frequently in groups P and F, respectively. Both had a significant improvement in BCVA, which was better in group F until 3 months, but not at 6 months. At 6 months, the ellipsoid zone and external limiting membrane were restored with no significant difference.

CONCLUSION

The single-layered inverted ILM flap was better for the closure of large MHs than ILM peeling, without using long-acting gas that prevents early rehabilitation.

Cannabinoid receptor 1 (CNR1) gene variant moderates neural index of cognitive disruption during nicotine withdrawal

Nicotine withdrawal-related disruption of cognitive control may contribute to the reinforcement of tobacco use. Identification of gene variants that predict this withdrawal phenotype may lead to tailored pharmacotherapy for smoking cessation. Variation on the cannabinoid receptor 1 gene (CNR1) has been related to nicotine dependence, and CNR1 antagonists may increase attention and memory functioning. We targeted CNR1 variants as moderators of a validated neural marker of nicotine withdrawal-related cognitive disruption. CNR1 polymorphisms comprising the 'TAG' haplotype (rs806379, rs1535255 and rs2023239) were tested independently, as no participants in this sample possessed this haplotype. Nicotine withdrawal-related cognitive disruption was indexed as increased resting electroencephalogram (EEG) alpha-1 power density across 17 electrodes. Seventy-three Caucasian Non-Hispanic smokers (≥15 cigarettes per day) visited the laboratory on two occasions following overnight smoking/nicotine deprivation. Either two nicotine or two placebo cigarettes were smoked prior to collecting EEG data at each session. Analyses showed that rs806379 moderated the effects of nicotine deprivation increasing slow wave EEG (P = 0.004). Smokers homozygous for the major allele exhibited greater nicotine withdrawal-related cognitive disruption. The current findings suggest potential efficacy of cannabinoid receptor antagonism as a pharmacotherapy approach for smoking cessation among individuals who exhibit greater nicotine withdrawal-related cognitive disruption.

Abstract P2-01-32: Second sentinel lymph node biopsy for patients with local recurrence after breast cancer surgery

Background: Sentinel lymph node biopsy(SLNB) has become standard procedure for primary breast cancer patients who have no tumor metastasis in sentinel lymph node(SLN). In this study, we evaluated feasibility and pathologic outcomes of second SLNB in patients with locally recurrent breast cancer and their follow-up results.

Methods: From January 2008 to December 2015, 114 patients underwent operation for locally recurrent breast cancer. In 42 patients of them, lymphatic mapping was performed for second SLNB. When SLN was visualized in lymphangiography, SLNB was performed. In the cases where SLN metastasis was confirmed, axillary lymph node dissection(ALND) was performed. Follow-up studies were performed every 6 months for 5 years and then annually.

Results: The mean interval to local recurrence from the initial surgery of breast cancer was 64.6±53.1 months. In 38 of 42 patients(90.5%), lymphatic mapping was successfully performed. There was no significant difference of success rate of lymphatic mapping according to previous operation method of breast and axilla or history of radiation therapy.

Aberrant lymphatic pathway was observed in 15 of 38 patients(39.5%). The rate of aberrant lymphatic pathway was higher in patients who underwent ALND previously then in patients who underwent SLNB only(81.8% vs 22.2%, p=0.001). In 6 patients who previously underwent ALND followed by radiation therapy, all their lymphatic pathway was altered. There was no significant difference of the rate of aberrant lymphatic pathway according to previous operation method of breast.

Of 38 patients in whom lymphatic mapping was successfully performed, 37 patients underwent SLNB. SLNs were identified in 31 patients(83.8%). There was no significant difference of success rate of SLNB according to previous operation method of breast and axilla or history of radiation therapy.

Of 31 patients whose SLNs were identified, 4 patients(12.9%) had tumor metastasis in their SLN. Among them, 3 patients underwent ALND but SLN was the only lymph node(LN) in which tumor metastasis was confirmed. The other patient underwent no further ALND because ipsilateral internal mammary LNs were only LNs in which tumor metastasis was confirmed in frozen section biopsy and micrometastasis was additionally confirmed in only one contralateral axillary LN in permanent biopsy.

The mean follow-up period after operation for local recurrence was 33.0±24.5 months. There were 10 cases(23.8%) of loco-regional recurrence or distant metastasis at 14 months of mean follow-up. Among them, one patient had ipsilateral axillary recurrence solitary at 11 months of follow-up. The patient underwent breast conserving surgery and SLNB for primary breast cancer which stage was I. Second SLNB for local recurrence was tried at 48 months after first operation but SLN was not identified. Because there was no evidence of axillary LN metastasis in preoperative image study, no further ALND was performed.

Conclusion: Second SLNB should be considered for patients with locally recurrent breast cancer because occult LN metastasis could be identified in the ipsilateral axilla or other site through aberrant lymphatic pathway. Further studies are needed to verify accuracy of axillary staging using second SLNB and also its oncologic safety.

Citation Format: Park JY, Song JH, Choi JE, Lee SJ. Second sentinel lymph node biopsy for patients with local recurrence after breast cancer surgery [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-32.

Abstract P1-11-13: Re-excision rate in breast conservation surgery after neoadjuvant chemotherapy

Background : The goal of neoadjuvant chemotherapy is to reduce tumor size and convert mastectomy to breast-conservation surgery (BCS). In response to neoadjuvant chemotherapy, the regression rate and pattern of breast cancer is variable. And the re-excision rate to secure negative resection margin is reported limitedly in this case. The purpose of this study was to compare the re-excision rate and BCS success rate of patients who received and who did not received neoadjuvant chemotherapy.

Method : In this retrospective cohort study, between January 2009 and December 2012, total 256 women were included who had clinical T2 breast cancer and were planed to receive BCS as initial operation or neoadjuvant chemotherapy. Fifty-nine patients of them received neoadjuvant chemotherapy. Clinical data were collected including age, preoperative or initial clinical tumor size, mammographic microcalcifications, ultrasound multifocality and axillary nodal status, retrospectively. In the resected specimen from BCS, we reviewed the pathologic tumor size, multifocality, histologic type, hormone receptor and Her-2-neu status, ki67, DCIS and EIC component. The re-excision rate and BCS success rate were investigated. Univariate analysis and regression model were used for identify clinicopathologic factors associated with re-excision. To reduce the effect of selection bias, propensity score matching-based anaylsis was also performed.

Results : Of the 256 patients, 178 patients (90.4%, 178/197) received BCS finally in neoadjuvant group and 56 patients (94.9%, 56/59) in non-neoadjuvant group (p=0.406). There was no statistical difference in the re-excision rate between two groups (35.6% (21/59) in neoadjuvant group vs 34.0% (67/197) in non-neoadjuvant group, p=0.946). In propensity-matched cohorts (N=118), the re-excision rate was same in two groups (35.6% (21/59) in neoadjuvant group vs 35.6% (21/59) in non-neoadjuvant group, p=1.000). BCS success rate was higher in neoadjuvant group(94.9% 56/59) than non-neoadjuvant group (86.4%(51/59)), but there was no statistical difference (p=0.205). In this cohorts, clinicopathologic factors associated with re-excision were pathologic multifocality (OR=4.56, p=0.0142), high ki67 (≥50%) (OR=0.7, p=0.0243) and DCIS component (OR=2.67, p=0.0261) in logistic regression model.

Conclusion: This study showed neoadjuvant chemotherapy could increase the BCS success rate but could not decrease the re-excision rate. The re-excision rate is more associated with pathologic finding rather than effect of neoadjuvant chemotherapy.

Citation Format: Song JH, Park JY, Choi JE, Bae YK, Lee SJ. Re-excision rate in breast conservation surgery after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-11-13.

Tenofovir versus tenofovir plus entecavir for chronic hepatitis B with lamivudine resistance and entecavir resistance

We compared the viral suppressive efficacy of tenofovir disoproxil fumarate (TDF) mono-rescue therapy (TDF group) and TDF plus entecavir (ETV) combination-rescue therapy (TDF + ETV group) in chronic hepatitis B (CHB) patients with lamivudine resistance and entecavir resistance. One hundred and thirty-three CHB patients with lamivudine and entecavir resistance were investigated. Ninety-six patients were treated with TDF and 37 with TDF + ETV for at least 6 months. We compared the virologic response rate (HBV DNA level <20 IU/mL) between the two groups and identified the predictive factors of treatment outcome. There were no significant differences between the two groups in demographic characteristics. Up to 24 months [median: 18 (range 6-24) months], 85.4% and 89.2% of the TDF group and TDF + ETV group, respectively, achieved a virologic response (P=.068). Only the HBV DNA level at baseline was significantly associated with a virologic response in the multivariate analysis. In a subanalysis of patients with HBV DNA levels ≥4 log (IU/mL) at baseline, a higher proportion of patients in the TDF + ETV group than the TDF group achieved a virologic response (92.9% vs 68.3%; P<.001), while 90% of patients with HBV DNA (IU/mL) levels <4 log in all both TDF and TDF + ETV groups achieved a virologic response. TDF mono-rescue therapy is a reasonable option in patients with lamivudine resistance and entecavir resistance. However, the combination strategy should be considered in patients with high baseline HBV DNA levels.

Crystallization Kinetics of Lead Halide Perovskite Film Monitored by In Situ Terahertz Spectroscopy

Vibrational modes in the terahertz (THz) frequency range are good indicators of lead halide perovskite's crystallization phase. We performed real-time THz spectroscopy to monitor the crystallization kinetics in the perovskite films. First, THz absorptance was measured while the perovskite film was annealed at different temperatures. By analyzing the Avrami exponent, we observed an abrupt dimensionality switch (from 1D to 2D) with increasing temperature starting at approximately 90 °C. We also monitored the laser-induced crystallinity enhancement of the preannealed perovskite film. The THz absorptance increased initially, then subsequently decayed over a couple of hours, although the enhancement factor varies depending on the film crystallinity. In particular, the Avrami analysis implied that the light-induced crystallization was assisted by the 1D diffusion processes. The activation photon energy was measured at 2.3 eV, which indicated that enhanced crystallization originated from the photoinduced structural change of residual lead iodide at the grain boundary.

Folate and vitamin B12 concentrations are associated with plasma DHA and EPA fatty acids in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study

This study aimed to examine the association between vitamin B6, folate and vitamin B12 biomarkers and plasma fatty acids in European adolescents. A subsample from the Healthy Lifestyle in Europe by Nutrition in Adolescence study with valid data on B-vitamins and fatty acid blood parameters, and all the other covariates used in the analyses such as BMI, Diet Quality Index, education of the mother and physical activity assessed by a questionnaire, was selected resulting in 674 cases (43 % males). B-vitamin biomarkers were measured by chromatography and immunoassay and fatty acids by enzymatic analyses. Linear mixed models elucidated the association between B-vitamins and fatty acid blood parameters (changes in fatty acid profiles according to change in 10 units of vitamin B biomarkers). DHA, EPA) and n-3 fatty acids showed positive associations with B-vitamin biomarkers, mainly with those corresponding to folate and vitamin B12. Contrarily, negative associations were found with n-6:n-3 ratio, trans-fatty acids and oleic:stearic ratio. With total homocysteine (tHcy), all the associations found with these parameters were opposite (for instance, an increase of 10 nmol/l in red blood cell folate or holotranscobalamin in females produces an increase of 15·85 µmol/l of EPA (P value <0·01), whereas an increase of 10 nmol/l of tHcy in males produces a decrease of 2·06 µmol/l of DHA (P value <0·05). Positive associations between B-vitamins and specific fatty acids might suggest underlying mechanisms between B-vitamins and CVD and it is worth the attention of public health policies.

Morphological characteristics of visual cells in the endemic Korean loach Kichulchoia multifasciata (Pisces; Cobitidae) by microscopy

The visual cell of the retina in the Korean loach Kichulchoia multifasciata, a bottom-dwelling freshwater loach in shallow water, contains double cones and large rods. With light microscopy, the cones form a row mosaic pattern in which the partners of double cones are linearly oriented with a large rod. In a double cone or twin cone, the two members are unequal such that one cone may be longer than the other. An anatomical unit is apparent which consists of 5 rod cells and 15 double cone cells per 20 × 20 μm area. We found that the cone cells of outer segments are linked to the inner segment by so-called "calyceal process" using a scanning electron microscopy, unlike rod cells. In the transmission electron microscopy, the outer membrane shows piles of membrane discs surrounded by double membranes.

Surgery versus Nerve Blocks for Lumbar Disc Herniation : Quantitative Analysis of Radiological Factors as a Predictor for Successful Outcomes

OBJECTIVE

To assess the clinical and radiological factors as predictors for successful outcomes in lumbar disc herniation (LDH) treatment.

METHODS

Two groups of patients with single level LDH (L4-5) requiring treatment were retrospectively studied. The surgery group (SG) included 34 patients, and 30 patients who initially refused the surgery were included in the nerve blocks group (NG). A visual analogue scale (VAS) for leg and back pain and motor deficit were initially evaluated before procedures, and repeated at 1, 6, and 12 months. Radiological factors including the disc herniation length, disc herniation area, canal length-occupying ratio, and canal area-occupying ratio were measured and compared. Predicting factors of successful outcomes were determined with multivariate logistic regression analysis after the optimal cut off values were established with a receiver operating characteristic curve.

RESULTS

There was no significant demographic difference between two groups. A multivariate logistic regression analysis with radiological and clinical (12 months follow-up) data revealed that the high disc herniation length with cutoff value 6.31 mm [odds ratio (OR) 2.35; confidence interval (CI) 1.21-3.98] was a predictor of successful outcomes of leg pain relief in the SG. The low disc herniation length with cutoff value 6.23 mm (OR 0.05; CI 0.003-0.89) and high baseline VAS leg (OR 12.63; CI 1.64-97.45) were identified as predictors of successful outcomes of leg pain relief in the NG.

CONCLUSION

The patients with the disc herniation length larger than 6.31 mm showed successful outcomes with surgery whereas the patients with the disc herniation length less than 6.23 mm showed successful outcomes with nerve block. These results could be considered as a radiological criteria in choosing optimal treatment options for LDH.

Effect of Nicardipine on Haemodynamic and Bispectral Index Changes following Endotracheal Intubation

We investigated the effect of IV nicardipine on haemodynamic and bispectral index responses to the induction of general anaesthesia and intubation. Forty patients were randomly allocated to two groups of 20 to receive normal saline or nicardipine 15 μg/kg IV 30 s after induction. Ninety seconds later, tracheal intubation was performed. Systolic blood pressure, heart rate and bispectral index were measured at baseline, 1 min after induction, pre-intubation, and every minute until 5 min after endotracheal intubation. Rate–pressure product values were calculated. In the nicardipine group, systolic blood pressure decreased compared with the control group, and heart rate increased compared with the control group. Bispectral index and rate–pressure product showed no differences between the two groups. In conclusion, the administration of 15 μg/kg nicardipine IV does not affect anaesthetic depth in response to the induction of general anaesthesia and intubation.

Cardiac Arrest due to a Vagal Reflex Potentiated by Thoracic Epidural Analgesia

Reflex bradycardia and cardiac arrest may be the result of a vagal reflex, which can occur during a variety of surgical procedures. We report a patient who developed cardiac arrest as a result of a vagal reflex that was potentiated by thoracic epidural analgesia during general anaesthesia. A 53-year-old man was scheduled for subtotal gastrectomy because of an early gastric adenocarcinoma. After an epidural catheter had been inserted, general anaesthesia was induced. During surgery, an abdominal self-retaining retractor was set up but bradycardia and cardiac arrest developed. The patient returned to a normal sinus rhythm after successful resuscitation. We conclude that bradycardia as a result of a vagal reflex is mediated by potent abdominal wall traction and is potentiated by epidural analgesia. Early diagnosis and proper treatment can allow a full recovery, even in high-risk patients.

Initial experiences of laparoscopic intravesical detrusorraphy using the Politano-Leadbetter technique

INTRODUCTION

Minimally invasive laparoscopic surgical procedures are increasingly being used for the management of vesicoureteral reflux.

OBJECTIVE

We present our experience of the laparoscopic Politano-Leadbetter technique performed under pneumovesicum conditions, which allows an orthotopic ureteral location after vesicoureteral reflux correction. Our procedure recreates the new ureteric orifice in a normal anatomical position with potential less morbidity and better cosmesis.

STUDY DESIGN

Our series comprises ten cases. The three 5 mm ports were introduced through bladder wall under cystoscopic vision. A 5-0 monofilament traction suture was used and dissection was carried out. After the ureteral mobilization, the location of the new hiatus was selected in a straight line superior to the original orifice. Dissection of the submucosal tunnel was started from the new hiatus and advanced to the original hiatus and the ureter was gently drawn passed through the tunnel. The ureter was rolled up and muscle fibers were incised until ureter could freely move from the base of the new hiatus. Finally, after spatulation of the terminal part of the ureter, ureterovesical anastomosis was performed with intracorporeal suturing using 5-0 monofilament sutures.

RESULTS

The average operative time was 125 min, with an average of 93 min for unilateral and 133 min for bilateral reimplantation. Blood loss was minimal and drains were used selectively. Removal of urethral catheter was decided empirically after hematuria stopped. Mean catheterization time was 5.1 days. The mean postoperative hospital stay was 6.2 days.

DISCUSSION

This study had limitations: the small number of cases, follow-up period is relatively short and data on the pre-operative bladder capacity, catheter-related morbidity, pain control and cosmesis are lacking. But most cases showed positive clinical results including acceptable operating time and good resolution rate with minimal complication. Our Politano-Leadbetter transvesicoscopic ureteric reimplantation is safe and useful in the resolution of VUR, even though the laparoscopic ureteric reimplantation is technically demanding even for experienced pediatric surgeons. Considering the main advantages of endoscopic surgery, our new vesicoscopic technique could be an optional treatment to the open reimplantation and has merits because whole the procedure are performed within the bladder, so there is no risk of intraperitoneal organ injury.

CONCLUSION

Though the role of this new technique in the treatment of VUR remains to be determined, the technique could be an optional treatment to replace other surgical methods as a less invasive and effective therapeutic method.