Distributions of different types of nociceptive neurons in thalamic mediodorsal nuclei of anesthetized rats

Mediodorsal thalamic nucleus (MD) is a critical relay of nociception. This study recorded responses of MD neurons to noxious mechanical and thermal stimuli in isoflurane anesthetized rats. We found the threshold of noxious mechanical stimulation was 141 gw and that of noxious heat stimulation was 46 °C. A significantly higher percentage of noxious inhibitory neurons were found in the medial and central part of the MD, whereas a higher percentage of noxious excitatory neurons were found in the lateral part of the MD and adjacent intralaminar nuclei. The differential distribution of excitatory and inhibitory neurons implies functional differentiation between the medial and lateral part of the MD in nociception processing. Furthermore, by an analysis of the stimulus-response function (SRF), we found 80% of these excitatory neurons had a step-function or hat-shape-like SRF. This suggests that most of the MD neurons may serve as a system to distinguish innocuous versus noxious stimuli.

Role of the Frontal Sinus in Mediating Ocular Vestibular-Evoked Myogenic Potentials by Bone Vibration Stimuli Applied to the Forehead

This study investigated ocular vestibular-evoked myogenic potential (oVEMP) tests via Fpz and Fz taps to assess the role of the frontal sinus in mediating oVEMP elicitation. Forty healthy subjects and 80 patients with Ménière disease (MD) underwent a series of oVEMP tests via a minishaker tapping at the Fpz and Fz sites in a randomized order. Response rates of oVEMP test via various tapping sites were compared. Dimensions of the frontal sinus were measured via CT scan. A significantly negative correlation between the age and height of the frontal sinus was noted, and the cutoff age for discriminating present and absent Fpz oVEMPs in MD patients was 52 years. Additionally, oVEMPs by Fpz tapping were more efficiently presented in males than females, likely because of the greater resonance by the larger height of the frontal sinus in males (3.88 ± 0.68 cm) than females (3.42 ± 0.67 cm). In conclusion, the height of the frontal sinus plays a role in mediating the elicitation of oVEMPs. The oVEMPs could be easily elicited by the first-order bone vibration (Fpz/Fz tapping) coupled with the second-order resonance effect (with a high extent of the frontal sinus). Thus, initial tapping at the Fpz site is suggested. If it fails, try the Fz site for screening the oVEMPs.

Decreased Power but Preserved Bursting Features of Subthalamic Neuronal Signals in Advanced Parkinson's Patients under Controlled Desflurane Inhalation Anesthesia

Deep brain stimulation (DBS) surgery of the subthalamic nucleus (STN) under general anesthesia (GA) had been used in Parkinson's disease (PD) patients who are unable tolerate awake surgery. The effect of anesthetics on intraoperative microelectrode recording (MER) remains unclear. Understanding the effect of anesthetics on MER is important in performing STN DBS surgery with general anesthesia. In this study, we retrospectively performed qualitive and quantitative analysis of STN MER in PD patients received STN DBS with controlled desflurane anesthesia or LA and compared their clinical outcome. From January 2005 to March 2006, 19 consecutive PD patients received bilateral STN DBS surgery in Hualien Tzu-Chi hospital under either desflurane GA (n = 10) or LA (n = 9). We used spike analysis (frequency and modified burst index [MBI]) and the Hilbert transform to obtain signal power measurements for background and spikes, and compared the characterizations of intraoperative microelectrode signals between the two groups. Additionally, STN firing pattern characteristics were determined using a combined approach based on the autocorrelogram and power spectral analysis, which was employed to investigate differences in the oscillatory activities between the groups. Clinical outcomes were assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) before and after surgery. The results revealed burst firing was observed in both groups. The firing frequencies were greater in the LA group and MBI was comparable in both groups. Both the background and spikes were of significantly greater power in the LA group. The power spectra of the autocorrelograms were significantly higher in the GA group between 4 and 8 Hz. Clinical outcomes based on the UPDRS were comparable in both groups before and after DBS surgery. Under controlled light desflurane GA, burst features of the neuronal firing patterns are preserved in the STN, but power is reduced. Enhanced low-frequency (4–8 Hz) oscillations in the MERs for the GA group could be a characteristic signature of desflurane's effect on neurons in the STN.

High mammographic breast density predicts locoregional recurrence after modified radical mastectomy for invasive breast cancer: a case-control study

Background

We aimed to evaluate the influence of mammographic breast density at diagnosis on the risk of cancer recurrence and survival outcomes in patients with invasive breast cancer after modified radical mastectomy.

Methods

This case-control study included 121 case-control pairs of women diagnosed with invasive breast cancer between 2004 and 2009, and who had undergone modified radical mastectomy and had mammographic breast density measured before or at diagnosis. Women with known locoregional recurrence or distant metastasis were matched by pathological disease stage, age, and year of diagnosis to women without recurrence. Locoregional recurrence was defined as recurrence in the ipsilateral chest wall, or axillary, internal mammary, or supraclavicular nodes. The median follow-up duration was 84.0 months for case patients and 92.9 months for control patients.

Results

Patients with heterogeneously dense (50–75% density) and extremely dense (>75% density) breasts had an increased risk of locoregional recurrence (hazard ratios 3.1 and 5.7, 95% confidence intervals 1.1–9.8 and 1.2–34.9, p = 0.043 and 0.048, respectively) than did women with less dense breasts. Positive margins after surgery also increased the risk of locoregional recurrence (hazard ratio 3.3, 95% confidence interval 1.3–8.3, p = 0.010). Multivariate analysis that included dense breasts (>50% density), positive margin, no adjuvant radiotherapy, and no adjuvant chemotherapy revealed that dense breasts were significant factors for predicting locoregional recurrence risk (hazard ratio 3.6, 95% confidence interval 1.2–11.1, p = 0.025).

Conclusions

Our results demonstrate that dense breast tissue (>50% density) increased the risk of locoregional recurrence after modified radical mastectomy in patients with invasive breast cancer. Additional prospective studies are necessary to validate these findings.

Trial registration

The study is retrospectively registered with ClinicalTrials.gov, number NCT02771665, on May 11, 2016.

Breath-hold spin echosequence for assessing liver iron content

OBJECTIVE

To compare a multiple breath-hold, multiecho, multiplanar spin-echo (BHMEMPSE) magnetic resonance (MR) sequence with a TR of 300ms with a traditional multiecho, multiplanar spin-echo (MEMPSE) MR sequence for assessing liver iron content.

MATERIALS AND METHODS

This study was approved by the institutional review board; informed consent was waived. Liver R2 measurement was derived from the mono-exponential model by BHMEMPSE and MEMPSE MR sequences of a 1.5T MR machine in 30 thalassemia patients (9men, 21women, aged 27.7±6.8years). Hepatic iron contents were estimated using Ferriscan in all patients. The inter- and intra-observer agreement of the 2 MR sequences was also evaluated.

RESULTS

MEMPSE R2 values significantly correlated with Ferriscan iron content values (r=0.895, p<0.001) and serum ferritin concentration (r=0.661, p<0.001). BHMEMPSE R2 values significantly correlated with Ferriscan values (r=0.914, p<0.001) and serum ferritin concentration (r=0.608, p<0.001). The distribution of MEMPSE R2 values against BHMEMPSE R2 values revealed an excellent linear relationship (r=0.978, p<0.001). The inter- and intra-observer agreement of the 2 MR sequences was excellent, with an interclass correlation coefficient exceeding 0.9. The distribution of Ferriscan against BHMEMPSE R2 values revealed a curvilinear relationship (r=0.935, p<0.001).

CONCLUSIONS

The BHMEMPSE sequence exhibited comparable estimation for assessing liver iron content, comparable repeatability and a shorter acquisition time compared with the MEMPSE sequence. The BHMEMPSE sequence can serve as an adjunctive sequence to assess liver iron content.

Erectile dysfunction, loss of libido and low sexual frequency increase the risk of cardiovascular disease in men with low testosterone

INTRODUCTION

Testosterone deficiency increases the cardiovascular disease (CVD) risk.

AIM

To evaluate the effect of erectile dysfunction (ED), sexual frequency and hypogonadal symptoms on CVD risk.

METHODS

A total of 395 hypogonadal men aged 45-74 years were surveyed using the Androgen Deficiency in the Aging Male and the International Index of Erectile Function.

MAIN OUTCOME MEASURES

The 10-year CVD risk was measured with the Framingham Risk Score. Logistic regression was performed to obtain the odds ratios of sexual function and hypogonadal symptoms for a 10-year CVD risk ≥20% (high risk).

RESULTS

The mean age was 56.1 ± 6.7 years. The mean 10-year CVD risk of the whole cohort was 18.1% ± 11.4%, while 131 subjects (33.2%) were classified as high risk. Logistic regression revealed that ED severity was associated with CVD risk [OR = 2.37 (CI 1.24-4.51) for mild-to-moderate ED, OR = 4.39 (1.78-8.43) for moderate ED and OR = 12.81 (4.65-26.11) for severe ED]. Compared to sexual frequency <1 per month, sexual frequency ≥4 decreased the risk of high CVD risk [OR = 0.35 (0.23-0.780)]. Loss of libido [OR = 2.95 (1.91-4.12)] and less strong erection [OR = 3.87 (CI 2.11-4.95)] increased the risk of high CVD risk. All remained significant after adjustment for age and testosterone.

CONCLUSIONS

ED, decreased sexual frequency and loss of libido predict a high 10-year CVD risk in hypogonadal men.

Radiosensitization in esophageal squamous cell carcinoma: Effect of polo-like kinase 1 inhibition

PURPOSE

This study examined the efficacy of polo-like kinase 1 (PLK1) inhibition on radiosensitivity in vitro and in vivo by a pharmacologic approach using the highly potent PLK1 inhibitor volasertib.

METHODS AND MATERIALS

Human esophageal squamous cell carcinoma (ESCC) cell lines KYSE 70 and KYSE 150 were used to evaluate the synergistic effect of volasertib and irradiation in vitro using cell viability assay, colony formation assay, cell cycle phase analysis, and western blot, and in vivo using ectopic tumor models.

RESULTS

Volasertib decreased ESCC cell proliferation in a dose- and time-dependent manner. Combination of volasertib and radiation caused G2/M cell cycle arrest, increased cyclin B levels, and induced apoptosis. Volasertib significantly enhanced radiation-induced death in ESCC cells by a mechanism involving the enhancement of histone H3 phosphorylation and significant cell cycle interruption. The combination of volasertib plus irradiation delayed the growth of ESCC tumor xenografts markedly compared with either treatment modality alone.

CONCLUSIONS

The in vitro results suggested that targeting PLK1 might be a viable approach to improve the effects of radiation in ESCC. In vivo studies showed that PLK1 inhibition with volasertib during irradiation significantly improved local tumor control when compared to irradiation or drug treatment alone.

Three-dimensional analysis of the accuracy of optic and electromagnetic navigation systems using surface registration in live endoscopic sinus surgery

Background: This study presents the first report in the same patients on the time efficiency of surface registration as well as the navigational accuracy using optic and electromagnetic tracking systems. Methods: Thirty patients with bilateral chronic paranasal pansinusitis underwent endoscopic sinus surgery. After surface registration, the surgeries were performed on one side using optic navigation guidance and on the other side using electromagnetic navigation guidance. The intraoperative measurements performed included the time taken for the surface registration and surgical procedure on each side, as well as the navigation errors at the different locations. Results: The time for surface registration was significantly longer in the optic navigation group than the electromagnetic group. A comparison of the navigation errors along the 3 axes showed that the deviation in the medial-lateral direction was significantly less than that in the anterior-posterior and cranial-caudal directions in the optic navigation group as well as the electromagnetic group. Conclusions: The procedure for surface registration in both optic and electromagnetic guidance is efficient and convenient. The accuracy of both navigation systems is comparable and within acceptable ranges for clinical use. In addition, the best accuracy was measured in the medial-lateral direction compared with the other two axes.

Central Thalamic Deep-Brain Stimulation Alters Striatal-Thalamic Connectivity in Cognitive Neural Behavior

Central thalamic deep brain stimulation (CT-DBS) has been proposed as an experimental therapeutic approach to produce consistent sustained regulation of forebrain arousal for several neurological diseases. We investigated local field potentials (LFPs) induced by CT-DBS from the thalamic central lateral nuclei (CL) and the striatum as potential biomarkers for the enhancement of lever-pressing skill learning. LFPs were simultaneously recorded from multiple sites in the CL, ventral striatum (Vstr), and dorsal striatum (Dstr). LFP oscillation power and functional connectivity were assessed and compared between the CT-DBS and sham control groups. The theta and alpha LFP oscillations were significantly increased in the CL and striatum in the CT-DBS group. Furthermore, interhemispheric coherences between bilateral CL and striatum were increased in the theta band. Additionally, enhancement of c-Fos activity, dopamine D2 receptor (Drd2), and α4-nicotinic acetylcholine receptor (α4-nAChR) occurred after CT-DBS treatment in the striatum and hippocampus. CT-DBS strengthened thalamic-striatal functional connectivity, which demonstrates that the inter-regional connectivity enhancement might contribute to synaptic plasticity in the striatum. Altered dopaminergic and cholinergic receptors resulted in modulation of striatal synaptic plasticity's ability to regulate downstream signaling cascades for higher brain functions of lever-pressing skill learning.

Temporal assessment of vascular reactivity and functionality using MRI during postischemic proangiogenenic vascular remodeling

Postischemic angiogenesis is an important recovery mechanism. Both arteries and veins are upregulated during angiogenesis, but eventually there are more angiogenic veins than arteries in terms of number and length. It is critical to understand how the veins are modulated after ischemia and then transitioned into angiogenic vessels during the proangiogenic stage to finally serve as a restorative strength to the injured area. Using a rat model of transient focal cerebral ischemia, the hypercapnic blood oxygen level-dependent (BOLD) response was used to evaluate vascular reactivity, while the hyperoxic BOLD and tissue oxygen level-dependent (TOLD) responses were used to evaluate the vascular functionality at 1, 3, and 7days after ischemia. Vessel-like venous signals appeared on R2* maps on days 3 and 7, but not on day 1. The large hypercapnic BOLD responses on days 3 and 7 indicated that these areas have high vascular reactivity. The temporal correlation between vascular reactivity and the immunoreactivity to desmin and VEGF further indicates that the integrity of vascular reactivity is associated with the pericyte coverage as regulated by the VEGF level. Vascular functionality remained low on days 1, 3, and 7, as reflected by the small hyperoxic BOLD and large hyperoxic TOLD responses, indicating the low oxygen consumption of the ischemic tissues. These functional changes in proangiogenic veins may be critical for angiogenesis.

Deep-brain electrical microstimulation is an effective tool to explore functional characteristics of somatosensory neurons in the rat brain

In neurophysiology researches, peripheral stimulation is used along with recordings of neural activities to study the processing of somatosensory signals in the brain. However, limited precision of peripheral stimulation makes it difficult to activate the neuron with millisecond resolution and study its functional properties in this scale. Also, tissue/receptor damage that could occur in some experiments often limits the amount of responses that can be recorded and hence reduces data reproducibility. To overcome these limitations, electrical microstimulation (ES) of the brain could be used to directly and more precisely evoke neural responses. For this purpose, a deep-brain ES protocol for rat somatosensory relay neurons was developed in this study. Three male Wistar rats were used in the experiment. The ES was applied to the thalamic region responsive to hindpaw tactile stimulation (TS) via a theta glass microelectrode. The resulting ES-evoked cortical responses showed action potentials and thalamocortical relay latencies very similar to those evoked by TS. This result shows that the developed deep-brain ES protocol is an effective tool to bypass peripheral tissue for in vivo functional analysis of specific types of somatosensory neurons. This protocol could be readily applied in researches of nociception and other somatosensory systems to allow more extensive exploration of the neural functional networks.

The prevalence and the risk factors of testosterone deficiency in newly diagnosed and previously known type 2 diabetic men

INTRODUCTION

While the epidemiology of testosterone deficiency has been well described in men with previously known type 2 diabetes mellitus (T2DM), it was less reported in those with untreated, newly diagnosed T2DM.

AIM

The aim of this study was to investigate the prevalence and the risk factors of testosterone deficiency of men with newly diagnosed T2DM.

METHODS

The cross-sectional study included 105 men (mean age: 61.2 ± 6.8 years) with previously known T2DM and another 81 (57.8 ± 8.8 years) with newly diagnosed T2DM. All received health checkup and sex hormone measurement at our institute in 2009.

MAIN OUTCOME MEASURES

We calculated the prevalence and explored the risk factors of low total (<300 ng/dL) and free (<6 ng/dL) testosterone in men with newly diagnosed and previously known T2DM.

RESULTS

Men with previously known T2DM were older and had higher diastolic pressure and greater fasting glucose. There was no significant difference in total (358.0 [155.0] ng/dL vs. 363.0 [154.0] ng/dL, P=0.68) and free (7.2 [2.5] ng/dL vs. 7.4 [2.4]ng/dL, P=0.84) testosterone and sex-hormone binding globulin (SHBG) (27.3 [22.3]nmol/L vs. 28.7 [14.9]nmol/L, P=0.46). The prevalence of low total and free testosterone was 28.4% and 21.0%, respectively, in men with newly diagnosed T2DM, and was 26.7% and 19.0% in those with previously known T2DM. In men with previously known T2DM, better glycemic control (HbA1c <7%) was associated with a higher level of total testosterone and a lower risk of low total testosterone. Men with newly diagnosed and previously known T2DM shared similar risk factors of low total testosterone, including high HbA1c (≥ 7%), low SHBG (<20 nmol/L), obesity, hyperuricemia, hypertriglycemia, and metabolic syndrome. Elevated prostate-specific antigen was a protective factor of low total testosterone. However, none of these factors was associated with low free testosterone.

CONCLUSIONS

The prevalence and the risk factors of testosterone deficiency are similar between newly diagnosed and previously known type 2 diabetic men.

Quantitative computed tomography of pulmonary emphysema and ventricular function in chronic obstructive pulmonary disease patients with pulmonary hypertension

Objective

This study strived to evaluate the relationship between degree of pulmonary emphysema and cardiac ventricular function in chronic obstructive pulmonary disease (COPD) patients with pulmonary hypertension (PH) using electrocardiographic-gated multidetector computed tomography (CT).

Materials and Methods

Lung transplantation candidates with the diagnosis of COPD and PH were chosen for the study population, and a total of 15 patients were included. The extent of emphysema is defined as the percentage of voxels below -910 Hounsfield units in the lung windows in whole lung CT without intravenous contrast. Heart function parameters were measured by electrocardiographic-gated CT angiography. Linear regression analysis was conducted to examine the associations between percent emphysema and heart function indicators.

Results

Significant correlations were found between percent emphysema and right ventricular (RV) measurements, including RV end-diastolic volume (R² = 0.340, p = 0.023), RV stroke volume (R² = 0.406, p = 0.011), and RV cardiac output (R² = 0.382, p = 0.014); the correlations between percent emphysema and left ventricular function indicators were not observed.

Conclusion

The study revealed that percent emphysema is correlated with RV dysfunction among COPD patients with PH. Based on our findings, percent emphysema can be considered for use as an indicator to predict the severity of right ventricular dysfunction among COPD patients.

Transcatheter arterial embolization with N-butyl cyanoacrylate for nonvariceal upper gastrointestinal bleeding in hemodynamically unstable patients: results and predictors of clinical outcomes

PURPOSE

To assess the safety, efficacy, clinical outcomes, and prognostic factors associated with transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) for nonvariceal upper gastrointestinal (GI) hemorrhage in hemodynamically unstable patients.

MATERIALS AND METHODS

Between January 2008 and December 2012, 49 hemodynamically unstable patients (systolic blood pressure < 90 mm Hg and ongoing transfusion requirement) underwent emergency TAE with NBCA for nonvariceal upper GI bleeding and were included in the study. The technical (cessation of extravasation) and clinical (no residual bleeding within 7 d) success rates, incidence of ischemic complications, and clinical and technical predictors of recurrent bleeding within 30 days were analyzed.

RESULTS

The technical and clinical success rates were 98% and 71%, respectively. There were no ischemic bowel complications; one patient experienced hepatic infarction with elevated liver enzymes. The incidence of major complications was 2%. The incidence of rebleeding within 30 days was 39%. Hematologic malignancies (P = .017), coagulopathy (P = .003), steroid pulse therapy (P = .025), and the absence of NBCA in the target lesions (P = .003) were associated with recurrent bleeding.

CONCLUSIONS

NBCA embolization can be safely performed in hemodynamically unstable patients with active nonvariceal upper GI bleeding. The clinical factors associated with rebleeding might influence the clinical outcome.

Trends in the utilization of computed tomography and cardiac catheterization among children with congenital heart disease

Background/Purpose

Pediatric cardiac computed tomography (CT) is a noninvasive imaging modality used to clearly demonstrate the anatomical detail of congenital heart diseases. We investigated the impact of cardiac CT on the utilization of cardiac catheterization among children with congenital heart disease.

Methods

The study sample consisted of 2648 cardiac CT and 3814 cardiac catheterization from 1999 to 2009 for congenital heart diseases. Diagnoses were categorized into 11 disease groups. The numbers of examination, according to the different modalities, were compared using temporal trend analyses. The estimated effective radiation doses (mSv) of CT and catheterization were calculated and compared.

Results

The number of CT scans and interventional catheterizations had a slight annual increase of 1.2% and 2.7%, respectively, whereas that of diagnostic catheterization decreased by 6.2% per year. Disease groups fell into two categories according to utilization trend differences between CT and diagnostic catheterization. The increased use of CT reduces the need for diagnostic catheterization in patients with atrioventricular connection disorder, coronary arterial disorder, great vessel disorder, septal disorder, tetralogy of Fallot, and ventriculoarterial connection disorder. Clinicians choose either catheterization or CT, or both examinations, depending on clinical conditions, in patients with semilunar valvular disorder, heterotaxy, myocardial disorder, pericardial disorder, and pulmonary vein disorder. The radiation dose of CT was lower than that of diagnostic cardiac catheterization in all age groups.

Conclusion

The use of noninvasive CT in children with selected heart conditions might reduce the use of diagnostic cardiac catheterization. This may release time and facilities within the catheterization laboratory to meet the increasing demand for cardiac interventions.

In vitro differential diagnosis of clavus and verruca by a predictive model generated from electrical impedance

Background

Similar clinical appearances prevent accurate diagnosis of two common skin diseases, clavus and verruca. In this study, electrical impedance is employed as a novel tool to generate a predictive model for differentiating these two diseases.

Materials and Methods

We used 29 clavus and 28 verruca lesions. To obtain impedance parameters, a LCR-meter system was applied to measure capacitance (C), resistance (R_e), impedance magnitude (Z), and phase angle (θ). These values were combined with lesion thickness (d) to characterize the tissue specimens. The results from clavus and verruca were then fitted to a univariate logistic regression model with the generalized estimating equations (GEE) method. In model generation, log Z_SD and θ_SD were formulated as predictors by fitting a multiple logistic regression model with the same GEE method. The potential nonlinear effects of covariates were detected by fitting generalized additive models (GAM). Moreover, the model was validated by the goodness-of-fit (GOF) assessments.

Results

Significant mean differences of the index d, R_e, Z, and θ are found between clavus and verruca (p<0.001). A final predictive model is established with Z and θ indices. The model fits the observed data quite well. In GOF evaluation, the area under the receiver operating characteristics (ROC) curve is 0.875 (>0.7), the adjusted generalized R² is 0.512 (>0.3), and the p value of the Hosmer-Lemeshow GOF test is 0.350 (>0.05).

Conclusions

This technique promises to provide an approved model for differential diagnosis of clavus and verruca. It could provide a rapid, relatively low-cost, safe and non-invasive screening tool in clinic use.

Laparoendoscopic single-site (LESS) retroperitoneal partial adrenalectomy using a custom-made single-access platform and standard laparoscopic instruments: technical considerations and surgical outcomes

BACKGROUND

We previously reported our initial experience with laparoendoscopic single-site (LESS) retroperitoneal partial adrenalectomy using a custom-made single-port device and conventional straight laparoscopic instruments.

METHODS

Between December 2010 and February 2012, LESS retroperitoneal partial adrenalectomies were performed in 11 patients. Six patients had aldosterone-producing adenomas (APAs) and five patients had nonfunctioning tumors. A single-port access was created with an Alexis wound retractor (Applied Medical, Rancho Santa Margarita, CA, USA) through an incision of 2-3 cm beneath the tip of the 12th rib. All procedures were performed with straight laparoscopic instruments.

RESULTS

All LESS procedures were successfully completed without conversion to traditional laparoscopic conversion. The tumors ranged from 1 cm to 4.7 cm (mean, 2.3 cm). The operative time was 71-257 minutes (mean, 121 minutes). Most patients (n = 8) had minimal blood loss; the other three patients had a blood loss of 150 mL, 100 mL, and 100 mL. The mean hospital stay was 3 days (range, 1-6 days). There were no perioperative or postoperative complications. Pathological examinations revealed negative surgical margins in all specimens. All patients with Conn's syndrome had an improvement in blood pressure and normalization of plasma renin activity and serum aldosterone levels; all patients were free of potassium supplementation.

CONCLUSION

Our results clearly demonstrate that LESS retroperitoneal partial adrenalectomy can be performed safely and effectively using a custom-made single-access platform and standard laparoscopic instruments.

High-resolution structural and functional assessments of cerebral microvasculature using 3D Gas ΔR2*-mMRA

The ability to evaluate the cerebral microvascular structure and function is crucial for investigating pathological processes in brain disorders. Previous angiographic methods based on blood oxygen level-dependent (BOLD) contrast offer appropriate visualization of the cerebral vasculature, but these methods remain to be optimized in order to extract more comprehensive information. This study aimed to integrate the advantages of BOLD MRI in both structural and functional vascular assessments. The BOLD contrast was manipulated by a carbogen challenge, and signal changes in gradient-echo images were computed to generate ΔR2* maps. Simultaneously, a functional index representing the regional cerebral blood volume was derived by normalizing the ΔR2* values of a given region to those of vein-filled voxels of the sinus. This method is named 3D gas ΔR2*-mMRA (microscopic MRA). The advantages of using 3D gas ΔR2*-mMRA to observe the microvasculature include the ability to distinguish air-tissue interfaces, a high vessel-to-tissue contrast, and not being affected by damage to the blood-brain barrier. A stroke model was used to demonstrate the ability of 3D gas ΔR2*-mMRA to provide information about poststroke revascularization at 3 days after reperfusion. However, this technique has some limitations that cannot be overcome and hence should be considered when it is applied, such as magnifying vessel sizes and predominantly revealing venous vessels.

Low-cost tele-assessment system for home-based evaluation of reaching ability following stroke

OBJECTIVE

Tele-assessment techniques can provide healthcare professionals with easily accessible information regarding patients' clinical progress. Recently, kinematic analysis systems have been used to assess rehabilitative outcomes in stroke patients. Kinematic systems, however, are not compatible with tele-assessment. The objective of our study was to develop a tele-assessment system for acquiring kinematic data of forward reaching movements in stroke patients, with an emphasis on cost-effectiveness, portability, and ease of use.

MATERIALS AND METHODS

We selected four healthy control participants and eight hemiplegic stroke patients for our study. The stroke patients were classified as Brunnstrom stage III, stage IV, or stage V. Our tele-assessment system used two three-axes accelerometers, a potentiometer, a multifunctional data acquisition card, and two computers. A standardized kinematic system was applied simultaneously to validate the measurements recorded by our tele-assessment system during five repetitions of forward reaching movements.

RESULTS

The correlation coefficients of the reaching displacement, velocity, and acceleration measurements obtained using our tele-assessment system and the standardized kinematic system were 0.956, 0.896, and 0.727, respectively. Differences in the maximum reaching distance and the maximum reaching velocity of forward reaching movements were observed among the study groups. There were no significant differences in the time required to complete the testing session among the study groups.

CONCLUSIONS

Our tele-assessment system is valid for the evaluation of upper-extremity reaching ability in stroke patients. Further research is needed to investigate the feasibility of the use of the tele-assessment system in patients' homes.

Ergonomic principles and techniques in facilitating advanced laparoendoscopic single site (LESS) urinary tract reconstruction with conventional laparoscopic instruments

BACKGROUND/PURPOSE

The technical and ergonomic details of laparoendoscopic single site (LESS) reconstruction have not been reported. In this study, we explored the feasibility and safety of performing advanced LESS upper urinary tract reconstruction with conventional laparoscopic instruments.

METHODS

Between September 2010 and March 2011, we retrospectively reviewed prospectively collected data from five patients who underwent LESS urinary tract reconstruction. The LESS reconstruction included pyeloureterostomy (N = 1), dismembered pyeloplasty (N = 2), ureteroneocystostomy (N = 1), and ureteroplasty for bifid blind ending ureter (N = 1). The perioperative and postoperative parameters were collected for analysis. The ergonomic principles and techniques are detailed.

RESULTS

All reconstructive LESS procedures were completed successfully without open conversion or laparoscopic conversion. Ancillary ports or ancillary instruments were not applied in any of the patients. The mean patient age was 40.4 years. The mean operative time was 213 ± 69 minutes, the estimated blood loss ranged from minimal to 50 mL, and the mean hospital stay was 4.4 ± 4 days. No operation-related complication occurred.

CONCLUSION

Based on our ergonomic principles and suturing/knotting techniques, conventional laparoscopic instruments are feasible and safe for LESS urinary reconstructive procedures.

The use of porcine small intestine submucosa implants might be associated with a high recurrence rate following laparoscopic herniorrhaphy

BACKGROUND/PURPOSE

The efficacy of porcine small intestine submucosa (SIS) implants in hernia repair has rarely been reported and remained elusive. We herein report our experience to further elucidate the efficacy of SIS mesh in herniorrhaphy.

METHODS

Between June 2008 and October 2009, a total of 82 patients with 125 inguinal hernias undergoing endoscopic total extraperitoneal (TEP) herniorrhaphy were included. Seventy patients (with 108 hernias) had traditional polypropylene and 12 patients (with 17 hernias) had SIS mesh repair. Postoperative complications and recurrence rates were compared between the two meshes.

RESULTS

The demographics between two groups were similar. All operations were performed smoothly with laparoscopy, and the postoperative courses were uneventful. After a median follow-up of 18 months, five (7%) in the polypropylene group and three (25%) in the SIS group had chronic pain (p = 0.09). Five of 17 (29.4%) hernia repairs in the SIS group had an ipsilateral recurrence, compared to no recurrence in the polypropylene group. In the five cases, the second laparoscopy revealed the SIS mesh had been totally degraded and there was no obvious fibrotic tissue in the previous mesh sites.

CONCLUSION

Our data suggest that the use of SIS mesh in endoscopic TEP herniorrhaphy might be associated with a high recurrence rate. The second look laparoscopy in these recurrent cases revealed slow and inadequate integration of host tissue. More evidence is still required to further evaluate the efficacy of SIS mesh in endoscopic TEP herniorrhaphy.