3D Echocardiography Provides Highly Accurate 3D Printed Models in Congenital Heart Disease

Cardiac 3D printing is mainly performed from magnetic resonance imaging (MRI) and computed tomography (CT) 3D datasets, though anatomic detail of atrioventricular (AV) valves may be limited. 3D echo provides excellent visualization of AV valves. Thus, we tested the feasibility and accuracy of 3D printing from 3D echo in this pilot series of subjects with congenital heart disease (CHD), with a focus on valve anatomy. Five subjects with CHD were identified. 3D echo data were converted to 3D printable files and printed in collaboration with 3D Systems Healthcare (Golden, Colorado). A novel technique for valve modeling was utilized using commercially available software. Two readers (KM, SA) independently measured valve structures from 3D models and compared to source echo images. 3D printing was feasible for all cases. Table 1 shows measurements comparing 2D echo to 3D models. Bland Altman analysis showed close agreement and no significant bias between 2D and digital 3D models (mean difference 0.0, 95% CI 1.1 to - 1.1) or 2D vs printed 3D models, though with wider limits of agreement (mean difference - 0.3, 95% CI 1.9 to - 2.6). Accuracy of 3D models compared to 2D was within < 0.5 mm. This pilot study shows 3D echo datasets can be used to reliably print AV and semilunar valve structures in CHD. The 3D models are highly accurate compared to the source echo images. This is a novel and value-added technique that adds incremental information on cardiac anatomy over current methods.

Serum DHEA-S levels could be used as a comparable diagnostic test to assess the pubertal growth spurt in dentofacial orthopedics

Background

Pubertal growth spurt assessment guides the timing of intervention for correcting the skeletal discrepancies in dentofacial orthopedics. Serum hormones are being studied for the skeletal age assessment to avoid unnecessary radiographic exposure. The present study is to evaluate the relationship of serum hormones dehydroepiandrosterone-sulfate (DHEA-S), insulin-like growth factor (IGF-1), and cervical vertebral stages (CS stages) in the skeletal age assessment of orthodontics patients around the circumpubertal age.

Methods

A total of ninety subjects with age ranging from 7 to 21 years were selected and divided into two groups based on the sex (45 males, 45 females). They were further distributed in each group based on the six CS stages determined from the lateral cephalogram. Blood samples from each subject were collected to evaluate the serum DHEA-S and IGF-1 levels by using the enzyme-linked immunosorbent assay (ELISA). Collected data were analyzed in SPSS software with a test of normalcy, unpaired t test, and one-way analysis of variance (ANOVA) followed by the least significant difference (LSD) post hoc comparison test and univariate regression analysis.

Results

The highest mean serum hormone levels were found in CS 4 in group A (male) and CS 3 in group B (female). ANOVA results showed that there was a significant difference in the serum hormone levels among the different CS stages in both the groups for both the hormones. Statistically, a significant difference was found between each CS stages for both the hormones except in the DHEA-S levels between CS 5 and CS 6.

Conclusions

The mean serum DHEA-S levels followed a typical pattern from the CS 1 till CS 6 which was comparable and similar to the mean serum IGF-1 levels in respect to CS stages. Thus, serum DHEA-S levels could be used as a possible diagnostic test for the assessment of the skeletal pubertal growth spurt in dentofacial orthopedics.

QRS detection using adaptive filters: A comparative study

Electrocardiogram (ECG) is one of the most important physiological signals of human body, which contains important clinical information about the heart. Monitoring of ECG signal is done through QRS detection. In this paper, an improved QRS detection algorithm, based on adaptive filtering principle, has been designed. Enumeration of the effectiveness of various LMS variants used in adaptive filtering based QRS detection algorithm has been done through fidelity parameters like sensitivity and positive predictivity. Whole family of LMS algorithm has been implemented for comparison. Sign-sign LMS, sign error LMS, basic LMS and normalized LMS are re-implemented, while variable leaky LMS, variable step-size LMS, leaky LMS, recursive least squares (RLS), and fractional LMS are novel combination presented in this paper. After analysis of the obtained results, performance of leaky-LMS algorithm is found to be the best with sensitivity, positive predictivity, and processing time of 99.68%, 99.84%, and 0.45s respectively. Reported results are tested and evaluated over MIT/BIH arrhythmia database. Presented study also concludes that the performance of most of the variants gets affected due to low SNR but the Leaky LMS performs better even under heavy noise conditions.

A review of troponin assay performance in Wales: can the same (method-dependent) decision limits be used in different sites?

An audit of troponin measurement protocols in use in Wales showed significant variations in practice with no consensus on analytical methods, or in the selection of a decision limit for the diagnosis of myocardial damage. Peer review data on assay imprecision at concentrations approaching the analytical limit of detection are lacking. The objective of the study was to establish clinically relevant precision profiles for the troponin methods used throughout Wales, which could be used to develop a standardized approach to the selection of a decision limit. A series of five pools of human serum spiked with troponin I-T complex were prepared and stored at -7°C until despatch. Five sets of each pool were dispatched to all Welsh laboratories and stored at -20°C until analysis. The analysis protocol consisted of two replicates of each pool per batch, and two batches per day for five days ( n=20). All the laboratories performed all the measurements in the same week. The lowest concentration providing a 10% coefficient of variation (CV) was 0.02 µg/L for the Roche method and 0.11 µg/L for the Beckman AccuTnI. The lowest concentrations that could be distinguishable from the 99th percentile reference limit were 0.02 µg/L for the Roche method and 0.07 µg/L for the Beckman AccuTnI. Current methods do not achieve the 10% CV at the 99th percentile reference limit proposed by the European Society of Cardiology. Use of the lowest concentration that can be reliably distinguished from the 99th percentile reference limit offers a novel alternative decision limit, which provides a slightly lower concentration than at the 10% CV but maintaining confidence in the assay that false-positive rates will be minimized.

Hybrid method based on singular value decomposition and embedded zero tree wavelet technique for ECG signal compression

BACKGROUND AND OBJECTIVE

In the field of biomedical, it becomes necessary to reduce data quantity due to the limitation of storage in real-time ambulatory system and telemedicine system. Research has been underway since very beginning for the development of an efficient and simple technique for longer term benefits.

METHOD

This paper, presents an algorithm based on singular value decomposition (SVD), and embedded zero tree wavelet (EZW) techniques for ECG signal compression which deals with the huge data of ambulatory system. The proposed method utilizes the low rank matrix for initial compression on two dimensional (2-D) ECG data array using SVD, and then EZW is initiated for final compression. Initially, 2-D array construction has key issue for the proposed technique in pre-processing. Here, three different beat segmentation approaches have been exploited for 2-D array construction using segmented beat alignment with exploitation of beat correlation. The proposed algorithm has been tested on MIT-BIH arrhythmia record, and it was found that it is very efficient in compression of different types of ECG signal with lower signal distortion based on different fidelity assessments.

RESULTS

The evaluation results illustrate that the proposed algorithm has achieved the compression ratio of 24.25:1 with excellent quality of signal reconstruction in terms of percentage-root-mean square difference (PRD) as 1.89% for ECG signal Rec. 100 and consumes only 162bps data instead of 3960bps uncompressed data.

CONCLUSION

The proposed method is efficient and flexible with different types of ECG signal for compression, and controls quality of reconstruction. Simulated results are clearly illustrate the proposed method can play a big role to save the memory space of health data centres as well as save the bandwidth in telemedicine based healthcare systems.

An efficient closed-form design method for nearly perfect reconstruction of non-uniform filter bank

In this paper, an efficient closed form method for the design of multi-channel nearly perfect reconstruction of non-uniform filter bank with the prescribed stopband attenuation and channel overlapping is presented. In this method, the design problem of multi-channel non-uniform filter bank (NUFB) is considered as the design of a prototype filter whose magnitude response at quadrature frequency is 0.707, which is exploited for finding the optimum passband edge frequency through empirical formula instead of using single or multivariable optimization technique. Two main attributes used in assessing the performance of filter bank are peak reconstruction error (PRE) and computational time (CPU time). As compared to existing methods, this method is very simple and easy to implement for NUFBs. To implement this algorithm, a Matlab program has been developed, and several examples are presented to illustrate the performance of proposed method.

Design of two-channel filter bank using nature inspired optimization based fractional derivative constraints

In this article, a novel approach for 2-channel linear phase quadrature mirror filter (QMF) bank design based on a hybrid of gradient based optimization and optimization of fractional derivative constraints is introduced. For the purpose of this work, recently proposed nature inspired optimization techniques such as cuckoo search (CS), modified cuckoo search (MCS) and wind driven optimization (WDO) are explored for the design of QMF bank. 2-Channel QMF is also designed with particle swarm optimization (PSO) and artificial bee colony (ABC) nature inspired optimization techniques. The design problem is formulated in frequency domain as sum of L2 norm of error in passband, stopband and transition band at quadrature frequency. The contribution of this work is the novel hybrid combination of gradient based optimization (Lagrange multiplier method) and nature inspired optimization (CS, MCS, WDO, PSO and ABC) and its usage for optimizing the design problem. Performance of the proposed method is evaluated by passband error (ϕp), stopband error (ϕs), transition band error (ϕt), peak reconstruction error (PRE), stopband attenuation (As) and computational time. The design examples illustrate the ingenuity of the proposed method. Results are also compared with the other existing algorithms, and it was found that the proposed method gives best result in terms of peak reconstruction error and transition band error while it is comparable in terms of passband and stopband error. Results show that the proposed method is successful for both lower and higher order 2-channel QMF bank design. A comparative study of various nature inspired optimization techniques is also presented, and the study singles out CS as a best QMF optimization technique.

Cuckoo search algorithm based satellite image contrast and brightness enhancement using DWT-SVD

This paper presents a new contrast enhancement approach which is based on Cuckoo Search (CS) algorithm and DWT-SVD for quality improvement of the low contrast satellite images. The input image is decomposed into the four frequency subbands through Discrete Wavelet Transform (DWT), and CS algorithm used to optimize each subband of DWT and then obtains the singular value matrix of the low-low thresholded subband image and finally, it reconstructs the enhanced image by applying IDWT. The singular value matrix employed intensity information of the particular image, and any modification in the singular values changes the intensity of the given image. The experimental results show superiority of the proposed method performance in terms of PSNR, MSE, Mean and Standard Deviation over conventional and state-of-the-art techniques.

Cyclosporine in Stevens Johnson syndrome and toxic epidermal necrolysis and retrospective comparison with systemic corticosteroid

BACKGROUND

Stevens Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening dermatological emergencies. Many immunosuppressive modalities have been tried with variable results.

AIMS

To determine the efficacy of cyclosporine in cases of SJS and TEN and compare the efficacy with systemic corticosteroid in the same condition.

METHODS

Study was conducted at a tertiary hospital during 01 July 2011 to 30 June 2012. SCORTEN was assessed at the time of admission. Total body surface area (TBSA) assessment was like any burn patients. Cyclosporine was administered in the dose of 3 mg/kg body weight in three divided dosage for 07 days and then tapered over another 07 days. Data were compared to a historical series of SJS/TEN patients, managed by systemic steroids a year ago.

RESULTS

A total of 11 consecutive patients with a mean age of 32.09 and standard deviation (SD 16.17) were enrolled in to cyclosporine group, which were retrospectively compared to 6 patients with a mean age of 27.87 (SD 13.97) years in the corticosteroid group. The mean duration of re-epithelialization was 14.54 (SD 4.08) and 23 days (SD 6.68) in cyclosporine and corticosteroid group respectively (P = 0.009956). Mean hospital stay was 18.09 (SD 5.02) and 26 (SD 6.48) days in cyclosporine and corticosteroid group respectively (P = 0.02597). A total of 1.11 and 0.51 patients were expected to die against no death and two deaths in cyclosporine and corticosteroid group respectively (Standardized mortality ratio = 3.92) (P = 0.04321).

CONCLUSION

This study definitely suggests that cyclosporine has encouraging role in the management of uncomplicated cases of SJS, SJS-TEN overlap or TEN.

EEG/ERP adaptive noise canceller design with controlled search space (CSS) approach in cuckoo and other optimization algorithms

This paper explores the migration of adaptive filtering with swarm intelligence/evolutionary techniques employed in the field of electroencephalogram/event-related potential noise cancellation or extraction. A new approach is proposed in the form of controlled search space to stabilize the randomness of swarm intelligence techniques especially for the EEG signal. Swarm-based algorithms such as Particles Swarm Optimization, Artificial Bee Colony, and Cuckoo Optimization Algorithm with their variants are implemented to design optimized adaptive noise canceler. The proposed controlled search space technique is tested on each of the swarm intelligence techniques and is found to be more accurate and powerful. Adaptive noise canceler with traditional algorithms such as least-mean-square, normalized least-mean-square, and recursive least-mean-square algorithms are also implemented to compare the results. ERP signals such as simulated visual evoked potential, real visual evoked potential, and real sensorimotor evoked potential are used, due to their physiological importance in various EEG studies. Average computational time and shape measures of evolutionary techniques are observed 8.21E-01 sec and 1.73E-01, respectively. Though, traditional algorithms take negligible time consumption, but are unable to offer good shape preservation of ERP, noticed as average computational time and shape measure difference, 1.41E-02 sec and 2.60E+00, respectively.

Surgical-orthodontic treatment of a skeletal class III malocclusion

For patients whose orthodontic problems are so severe that neither growth modification nor camouflage offers a solution, surgery to realign the jaws or reposition dentoalveolar segments is the only possible treatment option left. One indication for surgery obviously is a malocclusion too severe for orthodontics alone. It is possible now to be at least semiquantitative about the limits of orthodontic treatment, in the context of producing normal occlusion as the diagrams of the “envelope of discrepancy” indicate. In this case report we present orthognathic treatment plan of an adult female patient with skeletal class III malocclusion. Patient's malocclusion was decompensated by orthodontic treatment just before the surgery and then normal jaw relationship achieved by bilateral sagittal split osteotomy.

Association of availability of tobacco products with socio-economic and racial/ethnic characteristics of neighbourhoods

OBJECTIVE

To examine the association of neighbourhood median income and racial/ethnic composition with the availability of tobacco products in Omaha Metropolitan Area, Nebraska, USA.

METHODS

A total of 94 census tracts were selected at random. The outcome measures were the percentage of stores that sold tobacco and the number of stores that sold tobacco per square mile in each census tract.

RESULTS

Median household income was negatively associated (P<0.001), and percentage African American population (P<0.001) and percentage Hispanic population (P=0.049) were positively associated with the percentage of stores that sold tobacco. Median household income was negatively associated (P<0.001) and percentage Hispanic population (P=0.012) was positively associated with the number of stores that sold tobacco per square mile.

CONCLUSION

Policies that reduce the number of tobacco outlets might reduce social disparities in tobacco use.

Racial/ethnic and socioeconomic variations in duration of smoking: results from 2003, 2006 and 2007 Tobacco Use Supplement of the Current Population Survey

BACKGROUND

Little is known about racial/ethnic and socioeconomic variations in the duration of smoking. The goal of this research was to examine these variations.

METHODS

Data came from the 2003, 2006 and 2007 Tobacco Use Supplement of the Current Population Survey. The analysis was limited to ever-smokers (n = 117,168). The outcome was number of years of daily smoking. Survival analysis was employed to predict smoking duration.

RESULTS

American Indians with 32 years had the highest median duration of smoking, followed by Blacks and 'other' races with 30 years, Whites with 28 years and Hispanics with 24 years. The difference in the duration of smoking between Blacks and Whites disappeared after adjusting for poverty. Individuals in poverty had a median duration of smoking of 40 years, while those with a family income of at least three times that of the poverty threshold had a median duration of 22 years. Median duration of smoking was 40 years among individuals without a high-school diploma and 18 years among those with a bachelors or higher degree.

CONCLUSION

This research revealed large variations in smoking duration between racial/ethnic and socioeconomic groups. Longer exposure to tobacco among groups that are already disadvantaged is likely to exacerbate existing health disparities.

Work related complaints among dentists

The objective of this study was to describe the occurrence of neck pain, shoulder pain and back pain among dentists and to assess the risk factors affecting them. Sixty-eight dentists from Dharan and Biratnagar were interviewed using pretested questionnaires in January 2006. Back pain was the most common complaint affecting almost 80% of the study population, followed by neck pain (58.8%) and shoulder pain (47%). The frequency of shoulder pain among female dentists was nearly double that of males (P=0.009). The mean days of neck pain among males was significantly higher as compared to females (P=0.048). The study suggests that musculoskeletal complaints are common among dentists, though they are not of severe nature. There is a scope for further decreasing the prevalence and severity of these disorders by performing regular specific exercises.

Work Related Complaints among Dentists

The objective of this study was to describe the occurrence of neck pain, shoulder pain and back painamong dentists and to assess the risk factors affecting them.Sixty-eight dentists from Dharan and Biratnagar were interviewed using pretested questionnairesin January 2006. Back pain was the most common complaint affecting almost 80% of the study population, followed by neck pain (58.8%) and shoulder pain (47%). The frequency of shoulder pain among female dentists was nearly double that of males (P=0.009). The mean days of neck painamong males was significantly higher as compared to females (P=0.048). The study suggests that musculoskeletal complaints are commonamongdentists,thoughtheyarenot of severenature.Thereis a scope forfurtherdecreasingtheprevalence andseverityofthesedisordersbyperformingregularspecific exercises.Key words: back pain, dentists, neck pain, shoulder pain

Fungating primary locally malignant giant cell tumor of ulna: a case report

A giant cell tumor with local aggressiveness and penetration of cartilage is quite rare. We present a case of fungating giant-cell tumor of lower end of the ulna with wrist involvement including penetration of cartilage and diaphysis. Involvement with all these characteristics, according to the literature reviewed, is the first case of its type. We are of the opinion that the fungation may be due to incision and drainage and delayed presentation at tertiary care centre.

Cervical spine injuries in a teaching hospital of eastern region of Nepal: a clinico-epidemiological study

Cervical spine injuries with neural deficits carry significant impact economically, socially and psychologically to the individual and to the society. Risk factors involved, mode of injuries, constraints of management and rehabilitation are different in developing countries. Total 149 patients of cervical spine injuries presented in B.P. Koirala Institute of Health Sciences, Dharan, Nepal were evaluated prospectively for three years. Demographic details, etiology of injury, method and time taken for transportation and treatment method and progression of recovery were recorded. Most commonly involved age group was 30-49 years (44%) with male to female ratio of 4:1. Fall related injury especially from trees was the commonest mode of injury (60%). Patients were transported to hospital without neck immobilization (81%) in a vehicle unsuitable for spinal injuries patient with average delay of two days of injury. 79% had neural deficits among which 42% are with quadriparesis, 31% are with quadriplegia. Associated extra spinal injuries were found in 9% patients. Average hospital stay was 31 days. C5 vertebra was the most commonly injured vertebra. Cervical spine injuries, which has major impact over patient and society is still not adequately addressed by medical and public health system of developing countries like Nepal. Incidence of spinal injuries and its devastating consequences can be reduced by appropriate preventive measures and management along with rehabilitation.

Treatment of grade IIIB opens tibial fracture by Ilizarov hybrid external fixator

OBJECTIVE

We evaluated the results of patients who were treated with Ilizarov hybrid external fixator for type IIIB open tibial fractures.

MATERIALS AND METHODS

35 Gustilo grade IIIB tibial fractures of age between 18 to 42 years (22 male and 13 female) in which 12 distal fourth tibia (D/4) of C1.1 (6), C1.3 (6), 12 upper fourth Tibia (U/4) of A2 (8) and A3 (4) according to AO classification and 11 Tibial plateau fractures of Schatzker type VI (5) , V(5), IV(1) . All tibial plateau, proximal fourth fractures and lower fourth fractures of tibia and fibula (Reversed Hybrid), treated with Ilizarov hybrid fixator using two Ilizarov 5/8 rings and AO External fixator were followed up to 12-52 months.

RESULTS

D/4 fractures were united at 31.16678.3046 wks, U/4 at 24.005.2915 and Tibial plateau at 15.5454.160 weeks (p-0.00). ROM in tibial plateau type IV 130 degrees +/- 00, type V 124 degrees +/- 8.94 degrees, type VI 125 degrees +/- 7.0711 degrees, D/4 of type C1.1 (50 degrees +/- 0.00), type C1.3 (43 degrees +/- 5.7755) whereas full ROM in U/4 fractures. Pin tract infection occurred in 21% of cases. Pain on walking in 20% of cases of type VI tibial plateau fractures and 80% of cases of type IV and V. Problem free in rest of parameter of function of VI and 100% problem in IV and V. Pain at rest observed in 20% of cases in type V. In 66.67% U/4 fractures had pain on walking but no other functions were compromised. In 33% D/4 fractures of C1.1 type had pain on walking only and had 1cm of shortening.

CONCLUSION

On the basis of our experience, we suggest adopting this method for functional limb salvage after extensive complex high-energy injuries. This fixator is safe and versatile, effective in providing stability and allowing early rehabilitation, although the indications for its use are very relatively specific.

Complex elbow dislocation with ipsilateral segmental fracture of radius and ulna in a young boy: a complex injury with multiple fractures

Complex elbow dislocation1 (fracture of lateral condyle and avulsion fracture of medial epicondyle) with ipsilateral segmental fracture of radius and ulna without distal neurovascular deficit following machinery rolling belt injury in a 14 years boy presenting to emergency room of BP Koirala Institute of Health Sciences, is reported due to its complex nature of injury and good outcome after adequate follow up. The literature is reviewed for complex elbow dislocation to show its rarity.

Polyarticular tuberculosis in a young boy: a rare presentation

Polyarticular tuberculosis involving bilateral hip and bilateral knee joints without obvious pulmonary or disseminated form of tuberculosis in a young boy is presented along with literature review.

Comparison between external fixation and sliding hip screw in the management of trochanteric fracture of the femur in Nepal

We conducted a randomised controlled trial to compare external fixation of trochanteric fractures of the femur with the more costly option of the sliding hip screw. Patients in both groups were matched for age (mean 67 years, 50 to 100) and gender. We excluded all pathological fractures, patients presenting at more than one week, fractures with subtrochanteric extension or reverse obliquity, multiple fractures or any bone and joint disease interfering with rehabilitation. The interval between injury and operation, the duration of surgery, the amount of blood loss, the length of hospital stay and the cost of treatment were all significantly higher in the sliding hip screw group (p < 0.05). The time to union, range of movement, mean Harris hip scores and Western Ontario and McMaster University knee scores were comparable at six months. The number of patients showing shortening or malrotation was too small to show a significant difference between the groups. Pin-track infection occurred in 18 patients (60%) treated with external fixation, whereas there was a single case of wound infection (3.3%) in the sliding hip screw group.

Role of rehabilitation centres in reducing drug abuse problem in a town of Eastern Nepal

OBJECTIVES

This paper focuses to describe the role and activities of Drug Rehabilitation Centres (DRCs) in reducing the drug-abuse problem in Dharan. It also offers suggestions for increasing the effectiveness of prevention programs.

MATERIALS AND METHODS

Records of three DRCs working in Dharan for the past 9 years were analyzed using appropriate statistical tools.

RESULTS

The yearly clean rate is significantly higher in these centres. Harm reduction program was currently available only in one centre. Pharmacotherapy along with short-term rehabilitation was available at de-addiction unit of B. P. Koirala Institute of Health Sciences whereas long-term rehabilitation was at others centres.

CONCLUSION

Thus, there should be a strong coordination and network with each other to increase the effectiveness of the treatment program for drug abuse. The treatment centres should be increased in number as well as in quality. BPKIHS should take initiation to start long-term management with repeated booster programs.