Special issue of biomedical engineering letters on advances in intelligent prostheses

Liming Salvino,Wing Kong Chiu,Jerome Lynch,Kenneth J. Loh 대한의용생체공학회 2020 Biomedical Engineering Letters (BMEL) Vol.10 No.1

This Special Issue comprises original and review papersfrom engineering and medical professionals expounding onthe state of the art in engineering and the physical sciencesthat aim to enhance the performance of prosthetic devicesincluding socket prostheses and osseointegrated prostheses. Advances in physical science disciplines are poised torevolutionize how doctors and patients view and use prostheses. With monitoring and control capabilities, advancedprostheses can provide functionalities far beyond simplelimb extension and load support. Prostheses with built-insensing, embedded intelligence such as real-time monitoringand infection eradication, self-actuation, and control havebeen quickly advancing over the past 10 years or so. Giventhe rapid emergence of these transformative developments,this Special Collection is designed to collate a volume ofwork devoted to cutting-edge developments in advancesin intelligent prostheses that enhance medical care and thequality of life of patients with limb loss. Additionally, theseprosthetic functionalities and technologies may be utilized as“special wearables” to collect and mine human physiologicaldata in order to gain knowledge in fundamental scienceson neurological and biomechanical eff ects of injury andrehabilitation.

Modifi ed Radiology-Guided Percutaneous Gastrostomy (MRPG) for Patients with Complete Obstruction of the Upper Digestive Tract and Who are without Endoscopic or Nasogastric Access

Siu-Cheung Chan,Winnie Chiu-Wing Chu,Kar-Wai Liu,Chun-Ta Liao,Tsung-Shih Lee,Shu-Hang Ng 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.2

Objective: We wanted to report on our experience with modified radiology-guided percutaneous gastrostomy (MRPG) without endoscopic or nasogastric access for treating patients with complete obstruction of the upper digestive tract. Materials and Methods: Fourteen oncology patients (13 had hypopharyngeal cancer and 1 had upper esophageal cancer) with complete obstruction of the upper digestive tract were recruited. Conventional percutaneous endoscopic gastrostomy (PEG) and radiologic (fl uoroscopy-guided) percutaneous gastrostomy (RPG) were not feasible in all the patients. An MRPG technique (with a combination of ultrasound, an air enema and fl uoroscopic guidance) was performed in these patients. Results: We achieved successfully percutaneous gastrostomy using the modifi ed technique in all patients without any major or minor complications after the procedure. Conclusion: A modifi ed radiology-guided percutaneous gastrostomy technique can be safely performed in patients who failed to receive conventional PEG or RPG due to the absence of nasogastric access in the completely obstructed upper digestive tract. Objective: We wanted to report on our experience with modified radiology-guided percutaneous gastrostomy (MRPG) without endoscopic or nasogastric access for treating patients with complete obstruction of the upper digestive tract. Materials and Methods: Fourteen oncology patients (13 had hypopharyngeal cancer and 1 had upper esophageal cancer) with complete obstruction of the upper digestive tract were recruited. Conventional percutaneous endoscopic gastrostomy (PEG) and radiologic (fl uoroscopy-guided) percutaneous gastrostomy (RPG) were not feasible in all the patients. An MRPG technique (with a combination of ultrasound, an air enema and fl uoroscopic guidance) was performed in these patients. Results: We achieved successfully percutaneous gastrostomy using the modifi ed technique in all patients without any major or minor complications after the procedure. Conclusion: A modifi ed radiology-guided percutaneous gastrostomy technique can be safely performed in patients who failed to receive conventional PEG or RPG due to the absence of nasogastric access in the completely obstructed upper digestive tract.

Variations in Practice among Asia–Pacific Surgeons and Recommendations for Managing Cervical Myelopathy: The First Asia–Pacific Spine Society Collaborative Study

Jason Pui Yin Cheung,Prudence Wing Hang Cheung,Chee Kidd Chiu,Chris Yin Wei Chan,Mun Keong Kwan 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.1

Study Design: Surgeon survey. Purpose: To study the various surgical practices of different surgeons in the Asia–Pacific region. Overview of Literature: Given the diversity among Asia–Pacific surgeons, there is no clear consensus on the preferred management strategies for cervical myelopathy. In particular, the role of prophylactic decompression for silent cervical spinal stenosis is under constant debate and should be addressed. Methods: Surgeons from the Asia–Pacific Spine Society participated in an online questionnaire comprising 50 questions. Data on clinical diagnosis, investigations and outcome measures, approach to asymptomatic and silent cervical spinal stenosis, guidelines for surgical approach, and postoperative immobilization were recorded. All parameters were analyzed by the Mantel–Haenszel test. Results: A total of 79 surgeons from 16 countries participated. Most surgeons used gait disturbance (60.5%) and dyskinetic hand movement (46.1%) for diagnosis. Up to 5.2% of surgeons would operate on asymptomatic spinal stenosis, and 18.2% would operate on silent spinal stenosis. Among those who would not operate, most (57.1%) advised patients on avoidance behavior and up to 9.5% prescribed neck collars. For ossification of the posterior longitudinal ligament (OPLL), anterior removal was most commonly performed for one-level disease (p <0.001), whereas laminoplasty was most commonly performed for two- to four-level disease (p =0.036). More surgeons considered laminectomy and fusion for multilevel OPLL. Most surgeons generally preferred to use a rigid neck collar for 6 weeks postoperatively (p <0.001). Conclusions: The pooled recommendations include prophylactic or early decompression surgery for patients with silent cervical spinal stenosis, particularly OPLL. Anterior decompression is primarily suggested for one- or two-level disease, whereas laminoplasty is preferred for multilevel disease.

Enhancement of Elemental Sulfur Recovery from Wastewater Biogas Using Nickel (II)-(5,10,15,20)-tetrakis-phenylcarboxylporphyrin

Chun-Yin Lau,Jianyu Guan,Ho-Yin TSE,Chi Shun Yeung,Chiu Wing Shum,Shao-Yuan Leu 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.5

Sulfide control is a vital issue affecting the regional air quality and operational safety in sewage treatment processes. The conventional sulfide removal techniques are sophisticated industrial processes which require large operational footprint or are related to hazardous chemicals. In this study, the performance of elemental sulfur recovery from a simple micro-aeration process with metal-TCPP ((5,10,15,20)-tetrakis-p-carboxyphenylporphyrin) was investigated through laboratory experiments. A minimum of fourfold enhancement of elemental sulfur recovery was achieved from sulfide dissolved wastewater with the addition of nickel (II) TCPP, which demonstrated the highest among seven various types of transition metal-porphyrin complexes in the 3d block elements. The optimized reaction conditions resulted in 72.53% sulfur recovery with the addition of only 4.5 ppm nickel into the solution. The catalyst significantly improves the recyclability and life-cycle of the water-based absorbent and provides benefits to odor control and resource recovery.

Is Adjuvant Transarterial Chemoembolization Useful for Hepatocellular Carcinoma?

( Wong Hoi She ),( Cheung Tan To ),( Simon H. Y. Tsang ),( Wing Chiu Dai ),( Albert C. Y. Chan ),( Kenneth S. H. Chok ),( Kelvin K. C. Ng ),( Chung Mau Lo ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: Hepatectomy is the well-established curative treatment for hepatocellular carcinoma (HCC). However, adjuvant therapy is still controversial. This study tried to look into the effect of transarterial chemoembolization (TACE) in patients receiving hepatectomy for HCC. Methods: This is a retrospective study held in a single institution using prospectively maintained database for all the patients who underwent hepatectomy for HCC between January 2000 - December 2015. The perioperative details, pathological data and outcome were studied. Patients were matched at 1:10 ratio with comparable tumor size, number, indocyanine green retention test at 15 minutes, Child’s grading and tumor staging. The Kaplan-Meier method was used for survival analysis. The log-rank test was used for survival comparison. Results: There were total 1316 patients underwent hepatectomy for HCC. 38 patients with TACE were identified, and matched with 380 patients without TACE. The patients’ characteristics including age, sex, comorbidity, Child’s grading, ICG, tumor size and numbers were the same. The median sizes of the tumor were similar (9cm in TACE vs 8cm). There was no difference in terms of intraoperative management, extent of hepatectomy and postoperative complications. There were more patients with margin involvement in TACE group (23.7% vs 7.9%, p=0.004). The staging of the disease showed no significant difference in both groups. The disease free survival was similar (12.6 (TACE) vs 10.1months, p=0.794). There was no difference in overall survival with median survival of 27.8 (TACE) vs 36.9 months (5-year overall survival of 27.9% vs 41.2%, p=0.941). Conclusions: Margin involvement was known to be adverse factor for survival. Adjuvant TACE may benefit high-risk HCC patients with margin involvement as shown to have similar survival for those patients without margin involvement.

Effects and Mechanism of Turmeric Vasorelaxation of the Thoracic Aorta in Hypercholesterolemic Rats

Tsz-Shan Kam,Cho-Yee Wong,Pui-Long Kwan,Wing Fat-Yiu,Sin-Ming Chiu,Shun-Wan Chan,Kit-San Yuen,Robbie Chan 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.2

An extract of Curcuma longa was tested in hypercholesterolemic rats to investigate its potential therapeutic effect on vascular conditions. Four experimental groups were used: normal diet (ND) control group, high cholesterol diet (HCD) group, and HCD subgroups supplemented with turmeric extract at 100 or 300 mg/kg of body weight (HCD100Tur and HCD300Tur groups, respectively). Turmeric extract was fed orally to animals, and dietary treatments lasted for 28 days. Hypercholesterolemia developed in the HCD, HCD100Tur, and HCD300Tur rats. Segments of the thoracic aorta were isolated, and an organ bath experiment was used to assess the vasorelaxation capability among all rats. Rats fed only HCD showed a marked decrease in acetylcholine-induced vasorelaxation compared with ND control rats. The HCD100Tur and HCD300Tur rats showed significant improvement in vasorelaxation compared with HCD rats. When vasorelaxation was induced by high concentrations of sodium nitroprusside, no differences in vasorelaxation were observed among the four groups of rats. A mechanistic study showed that HCD100Tur and HCD300Tur rats had significantly higher levels of the antioxidant enzymes superoxide dismutase and glutathione peroxidase than HCD rats. The transcript levels of heat shock protein 70 (hsp70), bcl2, bax-a, caspase (casp3), and glyceraldehyde 3-phosphate dehydrogenase in aortic tissues indicated that hypercholesterolemia significantly increased the expression of bax-a and casp3 but down-regulated bcl2 expression compared with the control group. Turmeric increased the expression of hsp70 and bcl2 but greatly reduced casp3 expression,indicating that turmeric improves vasorelaxation of the aorta in hypercholesterolemic rats by increasing antioxidant enzyme activities and likely suppressing apoptosis.

The Risk of Upper Urinary Tract Involvement in Patients With Ketamine-Associated Uropathy

Chi-Hang Yee,Jeremy Yuen-Chun Teoh,Pui-Tak Lai,Vivian Yee-Fong Leung,Winnie Chiu-Wing Chu,Wai-man Lee,Yuk-Him Tam,Chi-Fai Ng 대한배뇨장애요실금학회 2017 International Neurourology Journal Vol.21 No.2

Purpose: The aims of this study were to investigate the prevalence of upper tract involvement in ketamine-associated uropathy, and to determine the predictors of hydronephrosis in patients with a history of ketamine abuse. Methods: This was a cross-sectional study of a prospective cohort of patients with ketamine-associated uropathy. Data including demographics, pattern of ketamine abuse, pelvic pain and urgency or frequency (PUF) symptom score, uroflowmetry (UFM) parameters, serum renal function, and liver function tests were collected. Upon consultation, ultrasonography was performed to assess the function of the urinary system. Results: From December 2011 to October 2015, we treated 572 patients with ketamine-associated uropathy. Of these patients, 207 (36.2%) had managed to achieve abstinence at the time of their first consultation. Ninety-six patients (16.8%) in the cohort were found to have hydronephrosis on ultrasonography. Univariate analysis identified age, duration of ketamine abuse, PUF symptom score, voided volume on UFM, serum creatinine levels >100 μmol/L, and an abnormal serum liver enzyme profile as factors associated with hydronephrosis. Logistic regression revealed the following parameters to be statistically related to hydronephrosis: age (adjusted odds ratio [OR], 1.090; 95% confidence interval [CI], 1.020–1.166; P=0.012), functional bladder capacity (adjusted OR, 0.997; 95% CI, 0.995–0.999; P=0.029), serum creatinine >100 μmol/L (adjusted OR, 3.107; 95% CI, 1.238–7.794; P=0.016, and an abnormal serum liver enzyme profile (adjusted OR, 1.967; 95% CI, 1.213–3.187; P=0.006). Conclusions: Ketamine-associated uropathy can involve the upper urinary tract. Patient demographics as well as investigations of UFM, renal function tests, and liver function tests may allow us to identify at-risk patients.

No difference in long-term functional outcomes or survivorship after total knee arthroplasty with or without computer navigation: a 17-year survivorship analysis

( Ng Jonathan Patrick ),( Lau Lawrence Chun Man ),( Chau Wai-wang ),( Ong Michael Tim-yun ),( Cheung Kin Wing ),( Chiu Kwok Hing ),( Chung Kwong Yin ),( Ho Kevin Ki-wai ) 대한슬관절학회 2021 대한슬관절학회지 Vol.33 No.-

Background: The literature comparing the long-term outcomes and survivorship of computer navigation-assisted and conventional total knee replacement (TKR) is sparse. Moreover, of the available comparative studies with followup duration of more than 10 years, the results seem to be conflicting. The purpose of this long-term study was to compare the clinical and radiological outcomes, and implant survivorship, of TKR performed with and without computer navigation. Methods: We retrospectively compared the results of 49 computer-navigated TKRs and 139 conventional TKRs. The mean age of the patients was 67.9 (range 52-81) years for the navigation group and 67.1 (range 50-80) years for the conventional TKR group. The mean duration of follow-up for the conventional and navigation TKR groups was 12.9 and 13.2 years, respectively. Clinical and radiographic follow-up examinations of the patients were performed at 2 weeks, 1 month, 3 months and 6 months post-operatively, and at 1-year intervals thereafter. Results: There were no significant differences in the post-operative Knee Society knee and function score between the two groups. The mean overall deviation from neutral alignment and the radiological outliers were significantly higher in the conventional TKR group. The overall survival rates at 17 years were 92.9% for the navigation group and 95.6% for the conventional TKR group (p = 0.62). Conclusions: Navigated TKR resulted in fewer radiological outliers; however, this did not translate to better long-term functional outcomes or implant survival.

Prospective randomized trial comparing efficacy and safety of intravenous and intra-articular tranexamic acid in total knee arthroplasty

Li Moses Man-Lung,Kwok Jojo Yan-Yan,Chung Kwong-Yin,Cheung Kin-Wing,Chiu Kwok-Hing,Chau Wai-Wang,Ho Kevin Ki Wai 대한슬관절학회 2020 대한슬관절학회지 Vol.32 No.-

Total knee arthroplasty (TKA) is associated with significant perioperative blood loss and postoperative allogenic blood transfusion. Tranexamic acid (TXA) reversibly blocks lysine binding sites on plasminogen molecules and inhibits plasmin formation. Comparisons of the efficacy and safety of intra-articular and intravenous TXA in primary TKA have not previously been reported.A prospective randomized trial was conducted in 150 patients who underwent TKA, and these patients were randomized into three groups. Patients in Group A were injected by intra-articular TXA according to body weight (20 mg/kg). Patients in Group B received a standard dose of intra-articular TXA (2000 mg), and those in Group C were infused with TXA according to body weight (20 mg/kg) before tourniquet deflation and again 3 h later. Baseline characteristics and data collected at blood transfusion were compared. Differences among four time points (baseline, day 0, day 2, and day 5) were carried out using ANOVA. The hemoglobin levels at postoperative day 5 were 10.6 g/dL for Group A, 10.6 g/dL for Group B, and 10.7 g/dL for Group C. The drain output was 399 ml for Group A, 314 ml for Group B, and 305 ml for Group C ( p = 0.03). Group C had significantly less drain output than Group A after post hoc comparisons ( p = 0.05), whereas no significant difference was observed between Group A and B ( p = 0.09) or between Group B and C. The weight-adjusted dose of TXA administered intravenously significantly reduced the drain output but not the total blood loss when compared with the weight-adjusted dose of TXA administered intra-articularly. No significant difference was observed in the other parameters among the three groups. The Joint CUHK-NTEC CREC, CRE-2013.644-T . Registered 1 March 2014.

Trends in contemporary advanced heart failure management: an in-depth review over 30 years of heart transplant service in Hong Kong

Yue Yan Katherine Fan,Ka Lam Wong,Ka Lai Cally Ho,Tai Leung Daniel Chan,Oswald Joseph Lee,Chi Yui Yung,Kin Shing Lun,Mo Chee Elaine Chau,Shui Wah Clement Chiu,Lik Cheung Cheng,Wing Kuk Timmy Au 대한이식학회 2022 Korean Journal of Transplantation Vol.36 No.4

Background: The year 2022 marks the 30th anniversary of heart transplant service in Hong Kong (HK). In this study, we describe prevailing trends and outcomes of advanced heart failure (AHF), including heart transplantations (HTx), in HK over the past 30 years. Methods: Trends in heart failure prevalence in HK from 1993 to 2021 were analyzed based on data from the Hospital Authority Clinical Data and Reporting System. All AHF patients referred for HTx consideration between 1992 and 2021 were reviewed. The bridge-to-transplant (BTT) utilization of short-term mechanical circulatory support (ST-MCS) devices, including venoarterial extracorporeal membrane oxygenation (VA-ECMO) and durable left ventricular assist devices (LVADs), from 2010 to 2021 was reviewed. Results: Overall, 237 heart transplants were performed in HK, with 10-year posttransplant and median survival of 68.1% and 18.7 years, respectively. An increase in AHF clinic referrals was correlated with increasing heart failure prevalence (R2=0.635, P<0.001). In total, 146 referrals were made for ST-MCS, and an observed increase in ST-MCS referrals was correlated with increasing VA-ECMO utilization (R2=0.849, P<0.001). Among 62 patients accepted for AHF therapy, those with durable LVAD implementation had better 1-year survival (71.5%) than those receiving an extracorporeal CentriMag (Levitronix) device as BTT (40%, P=0.008). In total, 143 LVADs were implanted, with 130 as BTT or bridge-to-candidacy (BTC) methods. The survival rate among the 130 BTT/BTC LVAD patients resembled that of HTx recipients (73.8% vs. 69.8% at 9 years, P=0.296). Conclusions: The burden of AHF management has increased and gained complexity over the past 30 years in Hong Kong.