Differentiation between normal and abnormal kidneys using 99mTc-DMSA SPECT with deep learning in paediatric patients

AIM

To investigate the feasibility of using deep learning (DL) to differentiate normal from abnormal (or scarred) kidneys using technetium-99m dimercaptosuccinic acid (99mTc-DMSA) single-photon-emission computed tomography (SPECT) in paediatric patients.

MATERIAL AND METHODS

Three hundred and one 99mTc-DMSA renal SPECT examinations were reviewed retrospectively. The 301 patients were split randomly into 261, 20, and 20 for training, validation, and testing data, respectively. The DL model was trained using three-dimensional (3D) SPECT images, two-dimensional (2D) maximum intensity projections (MIPs), and 2.5-dimensional (2.5D) MIPs (i.e., transverse, sagittal, and coronal views). Each DL model was trained to determine renal SPECT images into either normal or abnormal. Consensus reading results by two nuclear medicine physicians served as the reference standard.

RESULTS

The DL model trained by 2.5D MIPs outperformed that trained by either 3D SPECT images or 2D MIPs. The accuracy, sensitivity, and specificity of the 2.5D model for the differentiation between normal and abnormal kidneys were 92.5%, 90% and 95%, respectively.

CONCLUSION

The experimental results suggest that DL has the potential to differentiate normal from abnormal kidneys in children using 99mTc-DMSA SPECT imaging.

Reducing scan time of paediatric 99mTc-DMSA SPECT via deep learning

AIM

To investigate the feasibility of reducing the scan time of paediatric technetium 99m (^99mTc) dimercaptosuccinic acid (DMSA) single-photon-emission computed tomographic (SPECT) using a deep learning (DL) method.

MATERIAL AND METHODS

A total of 112 paediatric ^99mTc-DMSA renal SPECT scans were analysed retrospectively. Of the 112 examinations, 88 (84 for training and four for validation) were used to train a DL-based model that could generate full-acquisition-time reconstructed SPECT images from half-time acquisition. The remaining 24 examinations were used to evaluate the performance of the trained model.

RESULTS

DL-based SPECT images obtained from half-time acquisition have image quality similar to the standard clinical SPECT images obtained from full-acquisition-time acquisition. Moreover, the accuracy, sensitivity and specificity of the DL-based SPECT images for detection of affected kidneys were 91.7%, 83.3%, and 100%, respectively.

CONCLUSION

These preliminary results suggest that DL has the potential to reduce the scan time of paediatric ^99mTc-DMSA SPECT imaging while maintaining diagnostic accuracy.

Public knowledge of how to use an automatic external defibrillator in out-of-hospital cardiac arrest in Hong Kong

INTRODUCTION

The survival rate of out-of-hospital cardiac arrest in Hong Kong is low. A long delay between collapse and defibrillation is a contributing factor. Public access to defibrillation may shorten this delay. It is unknown, however, whether Hong Kong's public is willing or able to use an automatic external defibrillator. This study aimed to evaluate public knowledge of how to use an automatic external defibrillator in out-of-hospital cardiac arrest.

METHODS

A face-to-face semi-structured questionnaire survey of the public was conducted in six locations with a high pedestrian flow in Hong Kong.

RESULTS

In this study, 401 members of the public were interviewed. Most had no training in first aid (65.8%) or in use of an automatic external defibrillator (85.3%). Nearly all (96.5%) would call for help for a victim of out-of-hospital cardiac arrest but only 18.0% would use an automatic external defibrillator. Public knowledge of automatic external defibrillator use was low: 77.6% did not know the location of an automatic external defibrillator in the vicinity of their home or workplace. People who had ever been trained in both first aid and use of an automatic external defibrillator were more likely to respond to and help a victim of cardiac arrest, and to use an automatic external defibrillator.

CONCLUSION

Public knowledge of automatic external defibrillator use is low in Hong Kong. A combination of training in first aid and in the use of an automatic external defibrillator is better than either one alone.

Electricity production from municipal solid waste using microbial fuel cells

The organic content of municipal solid waste has long been an attractive source of renewable energy, mainly as a solid fuel in waste-to-energy plants. This study focuses on the potential to use microbial fuel cells to convert municipal solid waste organics into energy using various operational conditions. The results showed that two-chamber microbial fuel cells with carbon felt and carbon felt allocation had a higher maximal power density (20.12 and 30.47 mW m(-2) for 1.5 and 4 L, respectively) than those of other electrode plate allocations. Most two-chamber microbial fuel cells (1.5 and 4 L) had a higher maximal power density than single-chamber ones with corresponding electrode plate allocations. Municipal solid waste with alkali hydrolysis pre-treatment and K3Fe(CN)6 as an electron acceptor improved the maximal power density to 1817.88 mW m(-2) (~0.49% coulomb efficiency, from 0.05-0.49%). The maximal power density from experiments using individual 1.5 and 4 L two-chamber microbial fuel cells, and serial and parallel connections of 1.5 and 4 L two-chamber microbial fuel cells, was found to be in the order of individual 4 L (30.47 mW m(-2)) > serial connection of 1.5 and 4 L (27.75) > individual 1.5 L (20.12) > parallel connection of 1.5 and 4 L (17.04) two-chamber microbial fuel cells . The power density using municipal solid waste microbial fuel cells was compared with information in the literature and discussed.

Human leucocyte antigen-Cw6 as a predictor for clinical response to ustekinumab, an interleukin-12/23 blocker, in Chinese patients with psoriasis: a retrospective analysis

BACKGROUND

Ustekinumab, an interleukin-12/23 inhibitor, is effective in the treatment of psoriasis. A recent Italian study showed more favourable response to ustekinumab in patients with positive human leucocyte antigen (HLA)-Cw6. Nonetheless, there are differences in genetic susceptibility to psoriasis between races, and no studies have specifically assessed the candidate genetic markers in predicting therapy outcome in Chinese patients with psoriasis treated with ustekinumab.

OBJECTIVES

To determine whether HLA gene polymorphisms can predict the response to ustekinumab in Chinese patients with psoriasis.

METHODS

Sixty-six patients with psoriasis treated with ustekinumab were included in the study, and the effectiveness of ustekinumab therapy was evaluated at weeks 0, 16 and 28 by Psoriasis Area and Severity Index (PASI).

RESULTS

More HLA-Cw6-positive patients achieved a PASI 75 response at week 4 compared with HLA-Cw6-negative patients (38% vs. 9%, P = 0·019). Similarly, at week 16, patients carrying the HLA-Cw6 allele showed a higher likelihood of achieving PASI 50, 75 and 90 than Cw6-negative patients, although this was not statistically significant. At week 28, a significantly higher percentage of HLA-Cw6-positive patients maintained PASI 90 response compared with Cw6-negative patients (63% vs. 26%, P = 0·035). Further analysis of other HLA allele polymorphisms did not show significant associations with therapeutic response to ustekinumab.

CONCLUSIONS

This pharmacogenetic study provides preliminary data indicating that positive HLA-Cw6 is associated with a good response to ustekinumab treatment in Chinese patients with psoriasis.

Frequent activating HRAS mutations in trichilemmoma

BACKGROUND

Trichilemmoma is a benign follicular epithelial tumour exhibiting outer root sheath differentiation. It is associated with Cowden syndrome and naevus sebaceus (NS), but the pathogenesis of sporadic tumours is poorly understood. Recently, NS was found to be caused by postzygotic HRAS or KRAS mutations.

OBJECTIVES

We sought to determine whether NS-related and NS-unrelated trichilemmomas harbour RAS mutations.

METHODS

Formalin-fixed and paraffin-embedded blocks of 12 NS-related and 15 NS-unrelated trichilemmomas from 26 individuals were retrieved and analysed to determine the presence of mutations in exons 1 and 2 of the HRAS, KRAS and NRAS genes by polymerase chain reaction and direct sequencing. Mutational hotspots of the FGFR3 and PIK3CA genes were also analysed for NS-unrelated cases.

RESULTS

Among the 27 cases, mutually exclusive HRAS c.37G>C and c.182A>G mutations were observed in 17 and three tumours, respectively. Of the 12 NS-related tumours, 11 (92%) harboured the HRAS c.37G>C substitution. Of the 15 sporadic tumours, nine (60%) harboured HRAS mutations, including six c.37G>C and three c.182A>G. An HRAS c.182A>G mutation was observed only in sporadic tumours. No mutations were observed in the other genes that were tested.

CONCLUSIONS

The high frequency of HRAS activating mutations, including the c.182A>G substitution, which was rather rare in NS, suggests that most trichilemmomas are authentic neoplasms.

The safety profile of ustekinumab in the treatment of patients with psoriasis and concurrent hepatitis B or C

BACKGROUND

Ustekinumab, an interleukin (IL)-12 and IL-23 blocker, has emerged as a new therapeutic option for patients with psoriasis. It is generally well tolerated but safety data on the use of ustekinumab in patients with viral hepatitis are limited.

OBJECTIVE

To assess the safety profile of ustekinumab in the treatment of patients with psoriasis who have concomitant hepatitis B or hepatitis C.

METHODS

This study included 18 patients with concurrent psoriasis and hepatitis B virus (HBV) infection (14 patients) or hepatitis C virus (HCV) infection (four patients) who were treated with at least two ustekinumab injections. Viral loads were measured at baseline and each time before the administration of ustekinumab. Relevant clinical data were recorded.

RESULTS

Among 11 patients positive for hepatitis B surface antigen (HBsAg), two out of the seven (29%) patients who did not receive antiviral prophylaxis exhibited HBV reactivation during ustekinumab treatment. No viral reactivation was observed in the three occult HBV-infected patients (HBsAg-negative/hepatitis B core antibody-positive patients). One patient with HCV, liver cirrhosis and treated hepatocellular carcinoma (HCC) experienced HCV reactivation and recurrent HCC during the ustekinumab treatment. No significant increase in aminotransferase levels was observed in any patient.

CONCLUSIONS

Antiviral prophylaxis appears to minimize the risk of viral reactivation in patients with concurrent psoriasis and HBV infection. Without effective anti-viral prophylaxis, the risk/benefit of ustekinumab treatment should be carefully assessed in patients with psoriasis and HBV or HCV infection and/or HCC. Close monitoring for HBV and HCV viral load is recommended, particularly for patients with high-risk factors. Serum aminotransferase determination may not be useful for early detection of viral reactivation.

Effects of different SRT on anaerobic digestion of MSW dosed with various MSWI ashes

This study investigated different solid retention time (SRT) on municipal solid waste (MSW) anaerobic digestion with various MSW incinerator fly ash (FA) and bottom ash (BA) addition. Results showed that biogas production rates (BPRs, ≈ 200 to ≈ 400 mL/gVS) with organic loading rate of ≈ 0.053 gVS/gVS(reactor) (Day 1-435, SRT 20 days, SRT20) at FA 1g/d (FA1), BA 12 g/d (BA12) and BA 24 g/d (BA24) dosed bioreactors increased after adaptation. BPRs with SRT10 and SRT5 decreased while BPRs with SRT40 showed to increase compared to initial BPRs (≈ 200 mL/gVS) with SRT20. SRT5 operation reduced the BPRs (≈ 10 - ≈ 90 mL/gVS) significantly and only BA12 and BA24 dosed bioreactors could recover the BPRs (≈ 100 - ≈ 200 mL/gVS) after SRT20 operation (Day 613-617) compared to FA1 and FA3 and control. Released levels of Co, Mo and W at BA12 and BA24 dosed bioreactors showed most potential to improve MSW anaerobic digestion.

Effects of micro-nano and non micro-nano MSWI ashes addition on MSW anaerobic digestion

This study aims at investigating the effects of micro-nano municipal solid waste (MSW) incinerator (MSWI) fly ash (FA) and bottom ash (BA) on the MSW anaerobic digestion. Results showed that suitable micro-nano and non micro-nano MSWI ashes addition (FA/MSW 3, 6, 18 and 30 g g(-1) VS and BA/MSW 12, 36, 60 and 120 g g(-1) VS) could enhance the biogas production compared to the control. It was particularly found to have the highest biogas production at the micro-nano MSWI BA/MSW ratio of 36 g g(-1) VS (∼193 mL g(-1) VS MSW, ∼3.5 times to the control). Micro-nano MSWI FA and BA added bioreactors had the higher biogas production than the corresponding non micro-nano MSWI FA and BA added ones. Suitable MSWI ashes addition could improve the biogas production due to the released metals levels suitable for the MSW anaerobic digestion particularly found in the micro-nano added bioreactors.

Effects of spiked metals on the MSW anaerobic digestion

This study aimed to investigate the effects of eight metals on the anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) in bioreactors. Anaerobic bioreactors containing 200 mL MSW mixed completely with 200 m L sludge seeding. Ca and K (0, 1000, 2000 and 6,000 mg L(-1)) and Cr, Ni, Zn, Co, Mo and W (0, 5, 50 and 100 mg  L(-1)) of various dose were added to anaerobic bioreactors to examine their anaerobic digestion performance. Results showed that except K and Zn, Ca (~728 to ~1,461 mg  L(-1)), Cr (~0.0022 to ~0.0212 mg  L(-1)), Ni (~0.801 to ~5.362 mg  L(-1)), Co (~0.148 to ~0.580 mg  L(-1)), Mo (~0.044 to ~52.94 mg  L(-1)) and W (~0.658 to ~40.39 mg  L(-1)) had the potential to enhance the biogas production. On the other hand, except Mo and W, inhibitory concentrations IC(50) of Ca, K, Cr, Ni, Zn and Co were found to be ~3252, ~2097, ~0.124, ~7.239, ~0.482, ~8.625 mg  L(-1), respectively. Eight spiked metals showed that they were adsorbed by MSW to a different extent resulting in different liquid metals levels and potential stimulation and inhibition on MSW anaerobic digestion. These results were discussed and compared to results from literature.

Clinical experience of QuantiFERON(®) -TB Gold testing in patients with psoriasis treated with tumour necrosis factor blockers in Taiwan

BACKGROUND

In Taiwan, an intermediate tuberculosis burden country, around 9·3% of patients with rheumatoid arthritis treated with adalimumab develop tuberculosis despite prescreening with the tuberculin skin test. Within the Asia-Pacific region, the tuberculosis risk in patients with psoriasis who use tumour necrosis factor (TNF) blockers is unknown.

OBJECTIVES

This study reports the use of QuantiFERON(®) -TB Gold (QFT-G) (Cellestis, Melbourne, Vic., Australia) as a screening method for latent tuberculosis infection (LTBI) in patients with psoriasis.

METHODS

This retrospective review evaluated 216 patients with psoriasis in whom TNF blockers were considered between 2004 and 2009 in a tertiary referral hospital in Taiwan. Beginning in 2007, QFT-G was performed on all patients who were candidates for TNF blockers.

RESULTS

Seventeen patients who used TNF blockers for less than 4 weeks were excluded. Of the 147 assessed patients receiving TNF blockers, 110 (75%) underwent QFT-G tests. A total of 126 (86%) patients used etanercept and 40 (27%) patients used adalimumab. Nineteen patients switched between both. Overall, patients had a median of 24 weeks (range 4-307) exposure to TNF blockers. Twelve patients (11%) who were treated with TNF blockers and eight (15%) without TNF blockers had positive QFT-G results. Of all TNF blocker users, only one patient (0·68%) developed tuberculosis.

CONCLUSIONS

QFT-G can be used to screen for LTBI in a tuberculosis endemic area where bacille Calmette-Guérin vaccination coverage is high. Isoniazid prophylaxis is recommended for those who have positive QFT-G test results.

Modeling biogas production from organic fraction of MSW co-digested with MSWI ashes in anaerobic bioreactors

This study aims at investigating the effects of MSW incinerator fly ash (FA) and bottom ash (BA) on the anaerobic co-digestion of OFMSW with FA or BA. It also simulates the biogas production from various dosed and control bioreactors. Results showed that suitable ashes addition (FA/MSW 10 and 20 g L(-1) and BA/MSW 100 g L(-1)) could improve the MSW anaerobic digestion and enhance the biogas production rates. FA/MSW 20 g L(-1) bioreactor had the higher biogas production and rate implying the potential option for MSW anaerobic co-digestion. Modeling studies showed that exponential plot simulated better for FA/MSW 10 g L(-1) and control bioreactors while Gaussian plot was applicable for FA/MSW 20 g L(-1) one. Linear and exponential plot of descending limb both simulated better for BA/MSW 100 g L(-1) bioreactor. Modified Gompertz plot showed higher correlation of biogas accumulation than exponential rise to maximum plot for all bioreactors.

100-GHz transistors from wafer-scale epitaxial graphene

The high carrier mobility of graphene has been exploited in field-effect transistors that operate at high frequencies. Transistors were fabricated on epitaxial graphene synthesized on the silicon face of a silicon carbide wafer, achieving a cutoff frequency of 100 gigahertz for a gate length of 240 nanometers. The high-frequency performance of these epitaxial graphene transistors exceeds that of state-of-the-art silicon transistors of the same gate length.

Biostabilization assessment of MSW co-disposed with MSWI fly ash in anaerobic bioreactors

Municipal solid waste incinerator (MSWI) fly ash has been examined for possible use as landfill interim cover. For this aim, three anaerobic bioreactors, 1.2m high and 0.2m in diameter, were used to assess the co-digestion or co-disposal performance of MSW and MSWI fly ash. Two bioreactors contained ratios of 10 and 20 g fly ash per liter of MSW (or 0.2 and 0.4 g g(-1) VS, that is, 0.2 and 0.4 g fly ash per gram volatile solids (VS) of MSW). The remaining bioreactor was used as control, without fly ash addition. The results showed that gas production rate was enhanced by the appropriate addition of MSWI fly ash, with a rate of approximately 6.5l day(-1)kg(-1)VS at peak production in the ash-added bioreactors, compared to approximately 4l day(-1)kg(-1)VS in control. Conductivity, alkali metals and VS in leachate were higher in the fly ash-added bioreactors compared to control. The results show that MSW decomposition was maintained throughout at near-neutral pH and might be improved by release of alkali and trace metals from fly ash. Heavy metals exerted no inhibitory effect on MSW digestion in all three bioreactors. These phenomena indicate that proper amounts of MSWI fly ash, co-disposed or co-digested with MSW, could facilitate bacterial activity, digestion efficiency and gas production rates.

Solubility of heavy metals added to MSW

This paper aims to investigate the six heavy metal levels (Cd, Cr, Cu, Pb, Ni and Zn) in municipal solid waste (MSW) at different pHs. It intends to provide the baseline information of metals solubility in MSW co-disposed or co-digested with MSW incinerator ashes in landfill or anaerobic bioreactors or heavy metals contaminated in anaerobic digesters. One milliliter (equal to 1mg) of each metal was added to the 100ml MSW and the batch reactor test was carried out. The results showed that higher HNO3 and NaOH were consumed at extreme pH of 1 and 13 compared to those from pH 2 to 11 due to the comparably higher buffer capacity. Pb was found to have the least soluble level, highest metal adsorption (%) and highest partitioning Kd (lg(-1)) between pH 3 and 12. In contrast, Ni showed the highest soluble level, lowest metal adsorption (%) and lowest Kd (lg(-1)) between pH 4 and 12. Except Ni and Cr, other four metals seemed to show the amphibious properties as comparative higher solubility was found in the acidic and basic conditions.

Jar-opening challenges. Part 1: An apparatus for assessing hand and finger torques and forces in a jar-opening activity

A simulated jar apparatus was developed to record hand kinetics and torque contribution of a digit during jar-opening activities. The design of the apparatus, namely a jar body and a lid, is similar to a commercial jam jar that is regularly seen in daily living. One six-axis force—torque transducer and a torque cell were mounted inside the jar lid to detect the external force exerted from the digit and fixed on to the jar body to record the overall torque generated by the hand and wrist respectively. The applications of the apparatus were used to test the twisting torque of the hand and to measure the applied forces of the digit, which are both important factors in opening a jar. The contribution of each digit relative to the total twisting torque of the hand could be obtained via the apparatus. The intraclass correlation coefficient of the repeated measurements of the obtained forces and moments for different counterweights was approximately 0.96—1.00, which indicates that the reliability of the measured components of the apparatus is high. The high coefficient of determination ( r2 > 0.99) indicates high accuracy of prediction of the measured values with respect to the expected loads. The validation outcomes support the design rationale and actual body part of the simulated jar. In addition, understanding the contribution of a single digit in opening a jar was also achieved via the apparatus and model.

Comparison of ibuprofen and indometacin for early-targeted treatment of patent ductus arteriosus in extremely premature infants: a randomised controlled trial

BACKGROUND

To date there is no firm conclusion as to the efficacy and safety of ibuprofen compared with indometacin for patent ductus arteriosus (PDA) closure in extremely premature infants.

OBJECTIVE

To conduct a randomised controlled trial to better address this problem.

METHODS

119 infants (gestational age < or =28 weeks) with respiratory distress syndrome and PDA confirmed by echocardiography were randomly assigned to receive either indometacin (0.2 mg/kg) or ibuprofen (10 mg/kg), starting at <24 hours of life, followed by half these first doses within 48 hours at 24-hour intervals if indicated by echocardiographic PDA flow pattern.

RESULTS

The PDA closure rate and the doses of drug (mean (SD)) were similar in both groups: 53/60 (88.3%) and 1.9 (1.5) mg/kg in infants given ibuprofen, and 52/59 (88.1%) and 1.9 (1.7) mg/kg in infants given indometacin. No significant difference was found in the numbers of infants requiring surgical ligation, and the levels of post-treatment serum creatinine and urea nitrogen between the two groups. Although not significantly different, more infants (9/59 (15.3%)) treated with indometacin tended to develop oliguria (<1 ml/kg/h) than those treated with ibuprofen (4/60 (6.7%)). There were no significant differences in side effects or complications between the two groups.

CONCLUSIONS

Ibuprofen is as effective as indometacin for the early-targeted PDA treatment in extremely premature infants, without increasing the incidence of complications. When the echocardiographic PDA flow pattern was used as a guide for PDA treatment, fewer doses of drugs were needed to achieve acceptable closing rates.

Necrotizing fasciitis caused by Vibrio vulnificus: epidemiology, clinical findings, treatment and prevention

Necrotizing fasciitis is a soft-tissue infection with a high risk of fatality. Infection with Vibrio vulnificus can lead to development of necrotizing fasciitis and primary septicemia, and occurs mostly in immunocompromised host-associated diseases such as hepatic disease, diabetes mellitus, chronic renal insufficiency, and adrenal insufficiency. Early recognition and treatment of the infection, which are unclear, are vital to patient welfare. We studied the disease epidemiology and reviewed the prognosis and clinical features of patients treated using our developed protocol. Clinical manifestations and outcomes were retrospectively analyzed for 67 patients with V. vulnificus-mediated necrotizing fasciitis and sepsis. All patients who had contacted seawater or raw seafood with positive culture for vibrio were included. Patients were divided into two groups based on the timing of first fasciotomy and injury; within 24 h (group A) and beyond 24 h (group B). Twenty-three of the 67 patients (40%) had hepatic disease, 17 (25.4%) had chronic renal insufficiency, and 12 (17.9%) exhibited adrenal insufficiency. The most common site of infection was the upper extremity (74.7%). Group B presented with more clinical symptoms including fever (p = 0.02), hemorrhagic bullae (p < 0.0001), and shock (p = 0.007). Group A patients exhibited enhanced survival compared to group B (in hospital mortality: 4.9% vs. 23%; p = 0.005). We conclude that early and appropriate diagnosis for V. vulnificus infection should be made, especially in patients presenting with atypical clinical findings. Early fasciotomy within 24 h remains the highest priority and decreases the mortality rate.

Carbon nanotube linear bearing nanoswitches

We exploit the remarkable low-friction bearing capabilities of multiwalled carbon nanotubes (MWNTs) to realize nanoelectromechanical switches. Our switches consist of two open-ended MWNT segments separated by a nanometer-scale gap. Switching occurs through electrostatically actuated sliding of the inner nanotube shells to close the gap, producing a conducting ON state. For double-walled nanotubes in particular, a gate voltage can restore the insulating OFF state. Acting as a nonvolatile memory element capable of several switching cycles, our devices are straightforward to implement, self-aligned, and do not require complex fabrication or geometries, allowing for convenient scalability.

Ballistic phonon thermal transport in multiwalled carbon nanotubes

We report electrical transport experiments, using the phenomenon of electrical breakdown to perform thermometry, that probe the thermal properties of individual multiwalled carbon nanotubes. Our results show that nanotubes can readily conduct heat by ballistic phonon propagation. We determine the thermal conductance quantum, the ultimate limit to thermal conductance for a single phonon channel, and find good agreement with theoretical calculations. Moreover, our results suggest a breakdown mechanism of thermally activated C-C bond breaking coupled with the electrical stress of carrying approximately 10(12) A/m2. We also demonstrate a current-driven self-heating technique to improve the conductance of nanotube devices dramatically.

Secondary procedures following digital replantation and revascularisation

In this retrospective study, 79 digits of 55 patients received 102 secondary procedures following replantation. We divided the procedures into two groups, occurring before or after 2 months following replantation. The procedures in the early group were mainly for soft tissue coverage (92%), and those in that late group were mainly for tendon (67%) to improve function. Factors associated with higher incidence of early secondary procedures included multiple-finger injury, avulsion or degloving injury and level of injury proximal to zone III in finger replantation (p<0.05). However, younger patients and those with proximal level replantation in fingers had more late secondary procedures (p<0.05). Flexor tenolysis procedure significantly improved the digital function after replantation (p<0.05).

The validity of using a video-based motion analysis system for measuring maximal area of fingertip motion and angular variation

The aim of the study was to verify the application of a three-dimensional video motion analysis system to evaluate maximal fingertip motion area and angular variation of the hand by comparison and correlation with videofluoroscopic analysis. Eight normal subjects were recruited in this study. The maximal motion area of the fingertip and the angles of the metacarpal phalangeal (MP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints in performing five sequential postures for functional evaluation of the hand were measured using a video motion analysis system and a fluoroscopy system respectively. The results indicated that the intraclass correlation coefficient (ICC) of the calculated maximal fingertip motion area between the two methods was 0.9597. The ICC for total active motion (TAM) measurements of three finger joints was 0.940 between the surface and bony landmarks by fluoroscopy, 0.952 between the surface landmarks from fluoroscopy and motion analysis, and 0.927 between the bony landmark from fluoroscopy and surface markers from motion analysis. The ICC for angular measurements between three different paired assessments was 0.9650, 0.8896 and 0.8799 for the MP, PIP and DIP joints respectively. The results indicate that motion analysis is a practical method for assessing impairment of the hand.

Cross-limb vascular shunting as an auxiliary to major limb revascularisation

A 40-year-old male motorcyclist suffered a near-total amputation of his right foot. His limb was successfully salvaged with the aid of a cross-leg vascular shunt. Temporary arterial flow from the contralateral limb was transmitted via a pressure monitor tube to perfuse the avulsed part. This allowed the surgeon to carry out unhurried wound debridement, dissection of vital structures and skeletal fixation. The cannulation port was placed well distal to the proposed definitive anas<$>tomosis, to reduce damage to the endothelium. This procedure could be a valuable adjunct in major limb replantation, particularly in cases of prolonged ischaemia.

Positive association of ankylosing spondylitis with homozygous HLA-B2704, but protection with B2705 in Taiwan Chinese

The study was undertaken to determine the effects of HLA-B27 subtypes on susceptibility to ankylosing spondylitis (AS) in Taiwan Chinese, a polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP) method was developed for subtyping of HLA-B27. In this series, there are 62 patients with AS who were tested HLA-B27 positive serologically and 738 normal persons over the age of 65. Among the 738 normal controls, 42 (5.7%) were HLA-B27 positive. There were six (14.3%) homozygous for B2704, 18 (42.9%) heterozygous for B2704, 2 (4.8%) double heterozygous for B2704 and B2705, one (2.3%) double heterozygous for B2704 and B2706, 2 (4.8%) homozygous for B2705, 11 (26.1%) heterozygous for B2705, and 2 (4.8%) heterozygous for B2706. In our patients with AS, 37 (59.7%) were homozygous for B2704 and 25 (40.3%) were heterozygous for B2704. The HLA-B27 carrier rate in Taiwan healthy old persons is estimated at 5.7%. Susceptibility to AS is determined by homozygosity for B2704. However, B2705 may be an indicator of protection against AS in Taiwan Chinese.

A novel platelet-rich arterial thrombosis model in rabbits. Simple, reproducible, and dynamic real-time measurement by using double-opposing inverted-sutures model

Though numerous animal thrombosis models have been introduced, an easy, reliable, and reproducible arterial thrombosis model remains a continuing challenge prior to a thrombolytic study. In an effort to evaluate the efficiency of various recombinant thrombolytic agents with specific affinity to activated platelets in vivo, we developed a novel double-opposing inverted-sutures model to create a platelet-rich thrombus in the femoral artery of rabbits. The arteriotomy was done semicircumferentially, and variously sized microsurgical sutures were introduced intraluminally in a double-opposing inverted manner. The animals were divided into three groups according to the double-opposing inverted-sutures used: Group 1 with 10-0 nylon (n=6), Group 2 with 9-0 nylon (n=6), and Group 3 with 8-0 nylon (n=22). The superficial epigastric branch was cannulated with a thin polyethylene (PE) tube for intraarterial administration of the studied thrombolytic agent. The blood flow was continuously measured with a real-time ultrasonic flow meter. Within 2 h of installation of the sutures, there was no thrombus formation in either Group 1 or 2. In Group 3, the thrombosis rate was 91% (20 of 22) under a steady baseline flow (with an average of 12.23+/-2.40 ml/min). It was highly statistically significant with a P-value of .0000743 using Fisher's Exact Test. The averaged time to thrombosis was 21.8+/-9.8 min. The ultrasonic flow meter to record the dynamic real-time measurement of blood flow was a guideline for thrombus formation or dissolution, which was correlated with the morphological findings of stenotic status of the vessel detected by the Doppler sonography. The components of the thrombus were proven to be platelet-rich predominant by histological examination via hematoxylin and eosin (H&E) stain and transmission electron microscopy (TEM). To confirm that the double-opposing inverted-sutures model would be useful for a study of thrombolytic agents, we evaluated the effects of recombinant tissue-type plasminogen activator (rt-PA) and streptokinase-human plasminogen (SK-HPlg). The average time to thrombolysis post rt-PA infusion was 16.0+/-8.2 min and that of SK-HPlg was 79.6+/-23.1, which were similar to the previous reports. In conclusion, the novel double-opposing inverted-sutures (8-0 nylon) model provides a simple, reliable, and reproducible platelet-rich arterial thrombosis model with noninvasive and dynamic real-time measurement. It may be applied in assessing the efficiency of the recombinant thrombolytic agents and offers many advantages of an arterial platelet-rich in vivo thrombosis model.

Long-term effects of sensory reeducation following digital replantation and revascularization

The long-term maintenance of sensory gain following sensory reeducation is still unknown for replanted digits. Ten patients with 18 replanted or revascularized digits, who had received a formal sensory reeducation program for 1.5 years postoperatively, were reevaluated with moving two-point discrimination and Semmes-Weinstein pressure threshold test after discontinuing sensory reeducation for 1 year. Another four patients with seven replanted or revascularized digits, who have never received sensory reeducation after surgery, were also followed up in the same way. After cessation of sensory reeducation, the degree of moving two-point discrimination became significantly worse in the formal sensory-reeducated group (P < 0.05) and significantly improved in the group without sensory reeducation initially (P < 0.05), whereas it showed a nonsignificant change of Semmes-Weinstein threshold both in the group with formal sensory reeducation and without sensory reeducation. Sensory retraining did influence the progressive change of moving two-point discrimination, but not in a parallel way with the Semmes-Weinstein threshold test.

Free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation

Thirty-seven consecutive free anterolateral thigh flaps in 36 patients were transferred for reconstruction of head and neck defects following cancer ablation between January of 1997 and June of 1998. The success rate was 97 percent (36 of 37), with one flap lost due to a twisted perforator. The anatomic variations and length of the vascular pedicle were investigated to obtain better knowledge of anatomy and to avoid several surgical pitfalls when it is used for head and neck reconstruction. The cutaneous perforators were always found and presented as musculocutaneous or septocutaneous perforators in this series of 37 anterolateral thigh flaps. They were classified into four types according to the perforator derivation and the direction in which it traversed the vastus lateralis muscle. In type I, vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 56.8 percent of cases (21 of 37), and they were 4.83 +/- 2.04 cm in length. In type II, horizontal musculocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 27.0 percent of cases (10 of 37), and they were 6.77 +/- 3.48 cm in length. In type III, vertical septocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 10.8 percent of cases (4 of 37), and they were 3.60 +/- 1.47 cm in length. In type IV, horizontal septocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 5.4 percent of cases (2 of 37). They were 7.75 +/- 1.06 cm in length. The average length of vascular pedicle was 12.01 +/- 1.50 cm, and the arterial diameter was around 2.0 to 2.5 mm; two accompanying veins varied from 1.8 to 3.0 mm and were suitable for anastomosis with the neck vessels. Reconstruction of one-layer defect, external skin or intraoral lining, was carried out in 18 cases, through-and-through defect in 17 cases, and composite mandibular defect in two cases. With increasing knowledge of anatomy and refinements of surgical technique, the anterolateral thigh flap can be harvested safely to reconstruct complicated defects of head and neck following cancer ablation with only minimal donor-site morbidity.

Comparison of two-dimensional and three-dimensional techniques for determination of facial motion--absolute movement in a local face frame

BACKGROUND AND PURPOSE

Few studies have used motion analysis in the study of facial animation. A facial animation model using an expert vision motion analysis system was developed in this study to quantitatively evaluate absolute movement during five facial animations.

METHODS

Skin markers were adhered to the face of each subject at 16 anatomic landmarks selected to represent the functional movement of the facial muscles. Three of the 16 skin markers were used to establish a local face frame with the origin in the mid-point of the face. All of the coordinates measured in the laboratory frame were rotated and translated to the local face frame for analysis. The trajectory of the facial markers was evaluated from the local face frame when comparing two-dimensional (2-D) displacement of skin markers (frontal plane) with three-dimensional (3-D) values by paired Student's t-test.

RESULTS

Although the correlation of 2-D and 3-D displacements of skin markers was high (r > 0.69), the differences between 2-D and 3-D motion were significant (p < 0.001). The 2-D displacement of skin markers underestimated the 3-D facial animation in each marker and animation. There were no significant differences in the movement of both mouth angles or of the eyes. Thirty repeated measurements of a subject revealed good concentration in 3-D displacement, velocity, and angle of movement in smiling. The measurement error was less than 0.06 mm. The normative displacement of individual anatomic landmarks was evaluated to avoid size differences of individual faces.

CONCLUSIONS

We suggest that the expert vision motion analysis technique is feasible for quantitative evaluation of absolute facial movement and would be useful for further clinical evaluation of patients with facial palsy.

The use of the motion analysis system for evaluation of loss of movement in the finger

We have used the motion analysis system to measure loss of finger movement after injury. The motion analysis system can provide information about the dynamic angular changes of each finger joint and the fingertip motion area for the injured finger. The latter can be used to calculate the percentage of fingertip motion area preserved. A stiff finger may show limited fingertip motion area with the finger joints tending to flex and extend together.

A simple splinting method for correction of supple congenital clasped thumbs in infants

A splint has been designed to correct the congenital clasped thumb. It is like a short opponens splint that can keep the thumb in a position of abduction and extension without limiting wrist movement. The application of the splint was easy and adjustment for fit could be made at each visit if necessary. The device has been used in 11 infant patients (17 thumbs) with congenital clasped thumb of the supple type. The functional results were excellent in 15 of 17 thumbs, and the other two were good according to the grading system of Weckesser et al. (1968).

The motion analysis system and goniometry of the finger joints

The application of a video-based motion analysis system for goniometry of finger joints during measurement of the fingertip motion area has been assessed. The results indicate that the motion analysis system is reliable for angular measurements of finger joints that are comparable with those obtained by conventional goniometer. The advantages of using the motion analysis system is that it can record and show the changes in angle of all finger joints continuously during finger motion.

The motion analysis system and the fingertip motion area. Normal values in young adults

The reliability of the motion analysis system and the normal value of the fingertip motion area have been studied in young adults. The results indicate that the motion analysis system is a reliable tool for the evaluation of fingertip motion. It was found that the fingertip motion area in young adults has a linear correlation with the square of the finger length. Therefore, the normal value of the fingertip motion area can be calculated from the finger length.

Replantation of part of an ear as an open fan composite graft

A total amputation of the superior part of an ear with associated avulsion of adjacent scalp was treated successfully with a 'fan' technique, in which we unfolded the posterior skin envelope from the amputated ear segment and spread it onto part of the scalp defect of the temporal region. This resulted in a large area of contact between the composite graft and its recipient bed, with the added bonus of covering up some of the scalp defect. The remaining defect of the scalp was grafted with part of the avulsed scalp.

The motion analysis system and the maximal area of fingertip motion. A preliminary report

We have used the motion analysis system to evaluate the maximal area of fingertip motion. Some modification in setting the cameras and use of a smaller marker is required. In this series, 58 examinations have been accomplished on 28 fingers with various traumatic injuries. The closed curve derived from the motion analysis system and the area calculated from it were easier to interpret and could be compared in serial examinations. A high linear correlation between the fingertip motion area and total active motion was found. The computer-aided motion analysis system complements the traditional methods of assessing an injured finger.

Distraction lengthening of a replanted digit

The Ilizarov technique was used to lengthen a replanted middle finger on a musician's left hand. Bone consolidation was achieved in 6 months without the need for a bone graft. The elongated digit has good sensibility, appropriate stability, and sufficient length, which were essential for a good performance in her profession. The unique indication to apply the callus distraction technique in such a special condition was described, and the relative merits of other treatment alternatives were discussed.

A method of two-dimensional measurement for evaluating finger motion impairment. A description of the method and comparison with angular measurement

A new method has been designed for direct measurement of the two-dimensional range of motion (ROM) of the finger. The two-dimensional method encompasses the postures imposed by various combinations of contraction and relaxation of the finger motors, so that an individual muscle injury or adhesion might be more easily detected. The figures and values obtained from the two-dimensional method are easier to interpret than those from conventional measurements, making the progress of the rehabilitated finger more apparent. Since the passive ROM cannot be evaluated by this method, it is a supplement rather than a substitution for the conventional range of motion evaluation for each joint. The drawback of the two-dimensional method is that it is more difficult to use than the conventional method.

Evaluation of the effectiveness of sensory reeducation following digital replantation and revascularization

Sensory recovery following digital replantation plays an important role in the restoration of hand function. Twelve patients with twenty-four replanted or revascularized digits were randomly selected to enter a program of sensory reeducation, and another 15 patients with 22 replanted or revascularized digits were selected as controls who did not receive sensory reeducation. A moving two-point discrimination and a Semmes-Weinstein pressure threshold test were evaluated for monitoring the sensory recovery. The period of sensory reeducation was 18.83 weeks on average, and the mean follow-up time was 11.94 months. The group that received sensory reeducation significantly improved to a better degree of moving two-point discrimination and Semmes-Weinstein threshold level by both univariate and multiple regression analysis. We suggest that sensory reeducation should be an integral part of the postoperative rehabilitation protocol following digital replantation and revascularization.

Multivariate analysis of factors influencing the functional recovery after finger replantation or revascularization

A multivariate statistical analysis was utilized to study the influence of the four preoperative (age, mechanism of injury, level of injury, and type of amputation) and one postoperative (rehabilitation) variables on the functional recovery of the replanted or revascularized finger. Statistically significant differences are summarized as follows. The young age group have a better functional recovery due to better sensory recovery than the old age group. The crush injury group have a better functional recovery, with better scores in motion and patient satisfaction, than the avulsion injury group. The middle phalangeal injury group have a better functional recovery, with better score in motion and sensation than the proximal phalangeal injury group. There is no statistically significant difference in functional recovery between the revascularized and replanted fingers, but there is a significantly better sensory recovery in the revascularized finger. The rehabilitation group has a better functional recovery, with better score in motion, subjective symptoms, and patient satisfaction, than the nonrehabilitation group.

A technique for simultaneous replantation of multiple amputated digits at Tamai's Zone V

A technique for simultaneously replanting multiple digits amputated at Tamai's Zone V is described. Since these multiple amputated digits are connected together, they should be replanted as a single unit. The technique includes applying the pneumatic tourniquet first, debridement, bone shortening, and fixation of all the amputated digits, including tendon repairs, application of vascular clamps before releasing the tourniquet, followed by vascular anastomosis in one-by-one fashion for each digit. The disadvantage of this technique is the difficulty in keeping the digit cool. The advantages are it is a less time-consuming operation, there is reduced blood loss and contamination, and there is a better axial arrangement of the bony framework.

Influence of joint injury on motor and functional recovery of finger replantation

A series of 82 consecutive cases were studied concentrating on the influence of joint injury on the final motor and functional recovery of the successfully replanted or revascularized finger. In this series a 32.0% (41/128) incidence of joint injury was found. When the proximal interphalangeal (PIP) joint was injured and preservation was not possible, arthrodesis was done. This would cause a significantly lower Tamai's score (70.9), total active range of motion (TAM; 99.4 degrees) and TAM-minus the metacarpophalangeal joint TAM-MP; (15.6 degrees). The influence of arthrodesis on the distal interphalangeal (DIP) joint was relatively minor. When preservation of the joint was possible, the PIP arthroplasty group had a significantly higher Tamai's score (83.7, P < 0.01), TAM (157.9 degrees, P < 0.05), and TAM-MP (70.0 degrees, P < 0.001). Preservation of the DIP joint also significantly increased the TAM and TAM-MP degrees, yet with no significant improvement in Tamai's score. Our study proves what most hand surgeons would expect, in that sacrifices of the PIP and MP joint would cause a significantly detrimental effect on the functional recovery of a finger. We also recommend joint preservation during replantation surgery whenever possible, especially for the PIP and MP joints, in order to achieve better functional recovery of the finger.

Arterialized tendocutaneous venous flap for dorsal finger reconstruction

We describe three cases of combined loss of skin and tendon on the dorsum of the finger that were reconstructed with venous flaps. The technique is feasible and offers a good treatment modality for the small but complex defect on the dorsum of the finger by a one-stage operation.

Quantitative computed tomography for evaluation of orbital volume change in blow-out fractures

Measurement of orbital volume was conducted in 10 patients with blow-out fractures as well as in 20 controls. A bony orbital volume increase of up to 13.4+ +/- 6.0% was noted in the preoperative measurements. Proper reconstruction of the bony orbit in four patients reversed the volume change observed and achieved a satisfactory outcome. In the surgical techniques, we stress the importance of posterior floor restoration. Judicious analysis of the image and volume changes using computed tomography (CT) may offer great help in both pre- and postoperative assessments. An intimate correlation between the bony volume change and the observed degree of clinical enophthalmos has been confirmed. For a 1 mL increment in bony volume, there is a corresponding enophthalmos decrement of 1 mm on the Hertel exophthalmometer. In applying this information to clinical practice, we advocate that a bony volume change of over 8% (2 mL) usually implies a poor cosmetic outcome, thus indicating the need for surgical correction.

[Indications and contraindications of digital replantation]

With the development of microsurgery, replantation surgery have become the method of choice in treating the digit amputations. Although better than 90% of successful rate can be achieved in replanting guillotine type amputation, the final functional recovery is the main goal. The indications include: (1) thumb amputations, (2) Zone I amputation, (3) multiple digits, (4) bilateral amputation, (5) hemi-hand amputations, (6) hand amputation at wrist to upper forearm, and (7) pediatric amputations. And the contraindications include: (1) life-threatening associated injuries, (2) technically impossible, and (3) self-inflicted injuries. As for condition which have been previously put in the contraindication categories, such as: (1) single finger amputation, (2) Zone II amputations, (3) severe crush or avulsion injuries, (4) geriatric amputations, and (5) lengthy ischemia time amputations, the decision of to replant or not to replant was not a straight forward one. The decisions are individualized to meet the needs of different patients.

[Fournier's gangrene: report of 3 cases]

Fournier's gangrene is defined classically as a fulminant, rapidly spreading infection of the scrotum that also involves the perineum, penis and abdominal wall. The pathologic findings are described as synergistic gangrene secondary to a polymicrobial flora with a poorly defined portal of entry. We report 3 cases of Fournier's gangrene. Case 1 was a 67 years old who was admitted with the chief complaint of scrotal swelling and necrosis. Case 2 was a 59 years old who was admitted with the problem of scrotal swelling and pain, he had sought other medical help without success, and was then transferred to our hospital. Case 3 was a 62 years old who was admitted with the chief complaint of scrotal swelling and pain for 2 days. These 3 patients were all found to have diabetes mellitus. All 3 patients required aggressive surgical debridement, broad-spectrum antibiotics and adjunctive measures. Blood cultures were usually negative and pus cultures were typically aerobic gram-negative rods and gram-positive cocci and anaerobic bacteria of various types, especially Bacteroids fragilis. Our pus cultures revealed Escherichia coli and Staphylococcus aureus in Case 1, Enterobacter cloacae in Case 2 and E. coli, B. fragilis and Pseudomonas aeruginosa in Case 3. This disease is no longer a disease of young men. After 1945, the average age in 119 reported cases was 51.3 years and the average age of our cases was 62.7 years. Before the era of antibiotics, scrotal gangrene was not a rarity. In these modern times, in spite of seeking medical attention early, patients still developed scrotal gangrene and the mortality rate is high.(ABSTRACT TRUNCATED AT 250 WORDS)