1.Pancreaticoduodenectomy with superior mesenteric artery first-approach combined total meso-pancreas excision for periampullary malignancies:A high-volume single-center experience with short-term outcomes
Thanh Khiem NGUYEN ; Ham Hoi NGUYEN ; Tuan Hiep LUONG ; Kim Khue DANG ; Van Duy LE ; Duc Dung TRAN ; Van Minh DO ; Hong Quang PHAM ; Hoan My PHAM ; Thi Lan TRAN ; Cuong Thinh NGUYEN ; Hong Son TRINH ; Yosuke INOUE
Annals of Hepato-Biliary-Pancreatic Surgery 2024;28(1):59-69
Background:
s/Aims: Pancreaticoduodenectomy (PD) is the only radical treatment for periampullary malignancies. Superior mesenteric artery (SMA) first approach combined with total meso-pancreas (MP) excision was conducted to improve the oncological results.There has not been any previous research of a technique that combines the SMA first approach and total MP excision with a detailed description of the MP macroscopical shape.
Methods:
We prospectively assessed 77 patients with periampullary malignancies between October 2020 and March 2022 (18 months). All patients had undergone PD with SMA first approach combined total MP excision. The perioperative indications, clinical data, intra-operative index, R0 resection rate of postoperative pathological specimens (especially mesopancreatic margin), postoperative complications, and follow-up results were evaluated.
Results:
The median operative time was 289.6 min (178−540 min), the median intraoperative blood loss was 209 mL (30−1,600 mL).Microscopically, there were 19 (24.7%) cases with metastatic MP, and five cases (6.5%) with R1-resection of the MP. The number of lymph nodes (LNs) harvested and metastatic LNs were 27.2 (maximum was 74) and 1.8 (maximum was 16), respectively. Some (46.8%) patients had pancreatic fistula, but mostly in grade A, with 7 patients (9.1%) who required re-operations. Some 18.2% of cases developed postoperative refractory diarrhea. The rate of in-hospital mortality was 1.3%.
Conclusions
The PD with SMA first approach combined TMpE for periampullary malignancies was effective in achieving superior oncological statistics (rate of MP R0-resection and number of total resected LNs) with non-inferior short-term outcomes. It is necessary to evaluate survival outcomes with long-term follow-up.
2.Outcomes of laparoscopic choledochotomy using cholangioscopy via percutaneous-choledochal tube for the treatment of hepatolithiasis and choledocholithiasis:A preliminary Vietnamese study
Loi Van LE ; Quang Van VU ; Thanh Van LE ; Hieu Trung LE ; Khue Kim DANG ; Tuan Ngoc VU ; Anh Hoang Ngoc NGUYEN ; Thang Manh TRAN
Annals of Hepato-Biliary-Pancreatic Surgery 2024;28(1):42-47
Background:
s/Aims: Hepatolithiasis and choledocholithiasis are frequent pathologies and unfortunately, with the current treatment strategies, the recurrence incidence is still high. This study aimed to assess the outcomes of laparoscopic choledochotomy using cholangioscopy via the percutaneous-choledochal tube for the treatment of hepatolithiasis and choledocholithiasis in Vietnamese patients.
Methods:
A cross-sectional study of patients with hepatolithiasis and/or choledocholithiasis who underwent laparoscopic choledochotomy using intraoperative cholangioscopy via percutaneous-choledochal tube at the Department of Hepatopancreatobiliary Surgery, 108 Military Central Hospital, from June 2017 to March 2020.
Results:
A total of 84 patients were analyzed. Most patients were females (56.0%) with a median age of 55.56 years. Among them, 41.8% of patients had previous abdominal operations, with 33.4% having choledochotomy. All patients underwent successful laparoscopic common bile duct exploration followed by T-tube drainage without needing to convert to open surgery. Most patients (64.3%) had both intrahepatic and extrahepatic stones. The rate of stones ≥ 10 mm in diameter was 64.3%. Biliary strictures were observed in 19.1% of patients during cholangioscopy. Complete removal of stones was achieved in 54.8% of patients. Intraoperative complications were encountered in two patients, but there was no need to change the strategy. The mean operating time was 121.85 ± 30.47 minutes.The early postoperative complication rate was 9.6%, and all patients were managed conservatively. The residual stones were removed through the T-tube tract by subsequent choledochoscopy in 34/38 patients, so the total success rate was 95.2%.
Conclusions
Laparoscopic choledochotomy combined with cholangioscopy through the percutaneous-choledochal tube is a safe and effective strategy for hepatolithiasis and/or choledocholithiasis, even in patients with a previous choledochotomy.
3.Parenchymal-sparing anatomical hepatectomy based on portal ramification of the right anterior section: A prospective multicenter experience with short-term outcomes
Truong Giang NGUYEN ; Thanh Khiem NGUYEN ; Ham Hoi NGUYEN ; Hong Son TRINH ; Tuan Hiep LUONG ; Minh Trong NGUYEN ; Van Duy LE ; Hai Dang DO ; Kieu Hung NGUYEN ; Van Minh DO ; Quang Huy TRAN ; Cuong Thinh NGUYEN
Annals of Hepato-Biliary-Pancreatic Surgery 2024;28(1):25-33
Background:
s/Aims: Parenchymal-sparing anatomical hepatectomy (Ps–AH) based on portal ramification of the right anterior section (RAS) is a new technique to avoid unnecessarily transecting too much liver parenchyma, especially in cases of major anatomical hepatectomy.
Methods:
We prospectively assessed 26 patients with primary hepatic malignancies having undergone major Ps–AH based on portal ramification of the RAS from August 2018 to August 2022 (48 months). The perioperative indications, clinical data, intra-operative index, pathological postoperative specimens, postoperative complications, and follow-up results were retrospectively evaluated.
Results:
Among the 26 patients analyzed, there was just one case that had intrahepatic cholangiocarcinoma The preoperative level of α– Fetoprotein was 25.2 ng/mL. All cases (100%) had Child–Pugh A liver function preoperatively. The ventral/dorsal RAS was preserved in 19 and 7 patients, respectively. The mean surgical margin was 6.2 mm. The mean surgical time was 228.5 minutes, while the mean blood loss was 255 mL. In pathology, 5 cases (19.2%) had microvascular invasion, and in the group of HCC patients, 92% of all cases had moderate or poor tumor differentiation. Six cases (23.1%) of postoperative complications were graded over III according to the Clavien–Dindo system, including in three patients resistant ascites or intra-abdominal abscess that required intervention.
Conclusions
Parenchymal-sparing anatomical hepatectomy based on portal ramification of the RAS to achieve R0-resection was safe and effective, with favorable short-term outcomes. This technique can be used widely in clinical practice.
4.Successful surgical interventions for a giant and complicated myoepithelial carcinoma: a case report
Quang Vinh VU ; Thanh Tuan HOANG ; Van Anh TRAN ; Thanh Hai TONG ; Hong Ha NGUYEN
Archives of Craniofacial Surgery 2024;25(4):197-200
Ethmoid myoepithelial carcinoma is a rare tumor, with only 14 cases reported to date. This report discusses the largest tumor of this type ever recorded in the ethmoid region. The tumor caused extensive damage to facial structures, complicating treatment. The patient’s age and comorbidities increased the risk of intraoperative bleeding, presenting challenges to the complete removal of the tumor and the reconstruction of the damaged structures. To reduce the risk of intraoperative hemorrhage, shorten the surgery time, and manage potential heartrelated complications, arterial embolization was performed using gelatin sponges and coils. Definitive surgery was then carried out using a skin flap and mucosal flap to successfully reconstruct the defect. Postoperative radiotherapy was deemed unnecessary. The patient recovered well, with a satisfactory aesthetic outcome. No recurrence was observed during a 3-year follow-up period.
5.Systematic sequencing of imported cases leads to detection of SARS-CoV-2 B.1.1.529 (Omicron) variant in central Viet Nam
Do Thai Hung ; Nguyen Bao Trieu ; Do Thi Thu Thuy ; Allison Olmsted ; Trinh Hoang Long ; Nguyen Duc Duy ; Huynh Kim Mai ; Bui Thi Thu Hien ; Nguyen Van Van ; Tran Van Kiem ; Vo Thi Thuy Trang ; Nguyen Truong Duy ; Ton That Thanh ; Huynh Van Dong ; Philip L Gould ; Matthew R Moore
Western Pacific Surveillance and Response 2022;13(4):82-85
As authorities braced for the arrival of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infrastructure investments and government directives prompted action in central Viet Nam to establish capacity for genomic surveillance sequencing. From 17 November 2021 to 7 January 2022, the Pasteur Institute in Nha Trang sequenced 162 specimens from 98 150 confirmed SARS-CoV-2 cases in the region collected from 8 November to 31 December 2021. Of these, all 127 domestic cases were identified as the B.1.617.2 (Delta) variant, whereas 92% (32/35) of imported cases were identified as the B.1.1.529 (Omicron) variant, all among international flight passengers. Patients were successfully isolated, enabling health-care workers to prepare for additional cases. Most (78%) of the 32 Omicron cases were fully vaccinated, suggesting continued importance of public health and social measures to control the spread of new variants.
6.Global Impact of the COVID-19 Pandemic on Cerebral Venous Thrombosis and Mortality
Thanh N. NGUYEN ; Muhammad M. QURESHI ; Piers KLEIN ; Hiroshi YAMAGAMI ; Mohamad ABDALKADER ; Robert MIKULIK ; Anvitha SATHYA ; Ossama Yassin MANSOUR ; Anna CZLONKOWSKA ; Hannah LO ; Thalia S. FIELD ; Andreas CHARIDIMOU ; Soma BANERJEE ; Shadi YAGHI ; James E. SIEGLER ; Petra SEDOVA ; Joseph KWAN ; Diana Aguiar DE SOUSA ; Jelle DEMEESTERE ; Violiza INOA ; Setareh Salehi OMRAN ; Liqun ZHANG ; Patrik MICHEL ; Davide STRAMBO ; João Pedro MARTO ; Raul G. NOGUEIRA ; ; Espen Saxhaug KRISTOFFERSEN ; Georgios TSIVGOULIS ; Virginia Pujol LEREIS ; Alice MA ; Christian ENZINGER ; Thomas GATTRINGER ; Aminur RAHMAN ; Thomas BONNET ; Noémie LIGOT ; Sylvie DE RAEDT ; Robin LEMMENS ; Peter VANACKER ; Fenne VANDERVORST ; Adriana Bastos CONFORTO ; Raquel C.T. HIDALGO ; Daissy Liliana MORA CUERVO ; Luciana DE OLIVEIRA NEVES ; Isabelle LAMEIRINHAS DA SILVA ; Rodrigo Targa MARTÍNS ; Letícia C. REBELLO ; Igor Bessa SANTIAGO ; Teodora SADELAROVA ; Rosen KALPACHKI ; Filip ALEXIEV ; Elena Adela CORA ; Michael E. KELLY ; Lissa PEELING ; Aleksandra PIKULA ; Hui-Sheng CHEN ; Yimin CHEN ; Shuiquan YANG ; Marina ROJE BEDEKOVIC ; Martin ČABAL ; Dusan TENORA ; Petr FIBRICH ; Pavel DUŠEK ; Helena HLAVÁČOVÁ ; Emanuela HRABANOVSKA ; Lubomír JURÁK ; Jana KADLČÍKOVÁ ; Igor KARPOWICZ ; Lukáš KLEČKA ; Martin KOVÁŘ ; Jiří NEUMANN ; Hana PALOUŠKOVÁ ; Martin REISER ; Vladimir ROHAN ; Libor ŠIMŮNEK ; Ondreij SKODA ; Miroslav ŠKORŇA ; Martin ŠRÁMEK ; Nicolas DRENCK ; Khalid SOBH ; Emilie LESAINE ; Candice SABBEN ; Peggy REINER ; Francois ROUANET ; Daniel STRBIAN ; Stefan BOSKAMP ; Joshua MBROH ; Simon NAGEL ; Michael ROSENKRANZ ; Sven POLI ; Götz THOMALLA ; Theodoros KARAPANAYIOTIDES ; Ioanna KOUTROULOU ; Odysseas KARGIOTIS ; Lina PALAIODIMOU ; José Dominguo BARRIENTOS GUERRA ; Vikram HUDED ; Shashank NAGENDRA ; Chintan PRAJAPATI ; P.N. SYLAJA ; Achmad Firdaus SANI ; Abdoreza GHOREISHI ; Mehdi FARHOUDI ; Elyar SADEGHI HOKMABADI ; Mazyar HASHEMILAR ; Sergiu Ionut SABETAY ; Fadi RAHAL ; Maurizio ACAMPA ; Alessandro ADAMI ; Marco LONGONI ; Raffaele ORNELLO ; Leonardo RENIERI ; Michele ROMOLI ; Simona SACCO ; Andrea SALMAGGI ; Davide SANGALLI ; Andrea ZINI ; Kenichiro SAKAI ; Hiroki FUKUDA ; Kyohei FUJITA ; Hirotoshi IMAMURA ; Miyake KOSUKE ; Manabu SAKAGUCHI ; Kazutaka SONODA ; Yuji MATSUMARU ; Nobuyuki OHARA ; Seigo SHINDO ; Yohei TAKENOBU ; Takeshi YOSHIMOTO ; Kazunori TOYODA ; Takeshi UWATOKO ; Nobuyuki SAKAI ; Nobuaki YAMAMOTO ; Ryoo YAMAMOTO ; Yukako YAZAWA ; Yuri SUGIURA ; Jang-Hyun BAEK ; Si Baek LEE ; Kwon-Duk SEO ; Sung-Il SOHN ; Jin Soo LEE ; Anita Ante ARSOVSKA ; Chan Yong CHIEH ; Wan Asyraf WAN ZAIDI ; Wan Nur Nafisah WAN YAHYA ; Fernando GONGORA-RIVERA ; Manuel MARTINEZ-MARINO ; Adrian INFANTE-VALENZUELA ; Diederik DIPPEL ; Dianne H.K. VAN DAM-NOLEN ; Teddy Y. WU ; Martin PUNTER ; Tajudeen Temitayo ADEBAYO ; Abiodun H. BELLO ; Taofiki Ajao SUNMONU ; Kolawole Wasiu WAHAB ; Antje SUNDSETH ; Amal M. AL HASHMI ; Saima AHMAD ; Umair RASHID ; Liliana RODRIGUEZ-KADOTA ; Miguel Ángel VENCES ; Patrick Matic YALUNG ; Jon Stewart Hao DY ; Waldemar BROLA ; Aleksander DĘBIEC ; Malgorzata DOROBEK ; Michal Adam KARLINSKI ; Beata M. LABUZ-ROSZAK ; Anetta LASEK-BAL ; Halina SIENKIEWICZ-JAROSZ ; Jacek STASZEWSKI ; Piotr SOBOLEWSKI ; Marcin WIĄCEK ; Justyna ZIELINSKA-TUREK ; André Pinho ARAÚJO ; Mariana ROCHA ; Pedro CASTRO ; Patricia FERREIRA ; Ana Paiva NUNES ; Luísa FONSECA ; Teresa PINHO E MELO ; Miguel RODRIGUES ; M Luis SILVA ; Bogdan CIOPLEIAS ; Adela DIMITRIADE ; Cristian FALUP-PECURARIU ; May Adel HAMID ; Narayanaswamy VENKETASUBRAMANIAN ; Georgi KRASTEV ; Jozef HARING ; Oscar AYO-MARTIN ; Francisco HERNANDEZ-FERNANDEZ ; Jordi BLASCO ; Alejandro RODRÍGUEZ-VÁZQUEZ ; Antonio CRUZ-CULEBRAS ; Francisco MONICHE ; Joan MONTANER ; Soledad PEREZ-SANCHEZ ; María Jesús GARCÍA SÁNCHEZ ; Marta GUILLÁN RODRÍGUEZ ; Gianmarco BERNAVA ; Manuel BOLOGNESE ; Emmanuel CARRERA ; Anchalee CHUROJANA ; Ozlem AYKAC ; Atilla Özcan ÖZDEMIR ; Arsida BAJRAMI ; Songul SENADIM ; Syed I. HUSSAIN ; Seby JOHN ; Kailash KRISHNAN ; Robert LENTHALL ; Kaiz S. ASIF ; Kristine BELOW ; Jose BILLER ; Michael CHEN ; Alex CHEBL ; Marco COLASURDO ; Alexandra CZAP ; Adam H. DE HAVENON ; Sushrut DHARMADHIKARI ; Clifford J. ESKEY ; Mudassir FAROOQUI ; Steven K. FESKE ; Nitin GOYAL ; Kasey B. GRIMMETT ; Amy K. GUZIK ; Diogo C. HAUSSEN ; Majesta HOVINGH ; Dinesh JILLELA ; Peter T. KAN ; Rakesh KHATRI ; Naim N. KHOURY ; Nicole L. KILEY ; Murali K. KOLIKONDA ; Stephanie LARA ; Grace LI ; Italo LINFANTE ; Aaron I. LOOCHTAN ; Carlos D. LOPEZ ; Sarah LYCAN ; Shailesh S. MALE ; Fadi NAHAB ; Laith MAALI ; Hesham E. MASOUD ; Jiangyong MIN ; Santiago ORGETA-GUTIERREZ ; Ghada A. MOHAMED ; Mahmoud MOHAMMADEN ; Krishna NALLEBALLE ; Yazan RADAIDEH ; Pankajavalli RAMAKRISHNAN ; Bliss RAYO-TARANTO ; Diana M. ROJAS-SOTO ; Sean RULAND ; Alexis N. SIMPKINS ; Sunil A. SHETH ; Amy K. STAROSCIAK ; Nicholas E. TARLOV ; Robert A. TAYLOR ; Barbara VOETSCH ; Linda ZHANG ; Hai Quang DUONG ; Viet-Phuong DAO ; Huynh Vu LE ; Thong Nhu PHAM ; Mai Duy TON ; Anh Duc TRAN ; Osama O. ZAIDAT ; Paolo MACHI ; Elisabeth DIRREN ; Claudio RODRÍGUEZ FERNÁNDEZ ; Jorge ESCARTÍN LÓPEZ ; Jose Carlos FERNÁNDEZ FERRO ; Niloofar MOHAMMADZADEH ; Neil C. SURYADEVARA, MD ; Beatriz DE LA CRUZ FERNÁNDEZ ; Filipe BESSA ; Nina JANCAR ; Megan BRADY ; Dawn SCOZZARI
Journal of Stroke 2022;24(2):256-265
Background:
and Purpose Recent studies suggested an increased incidence of cerebral venous thrombosis (CVT) during the coronavirus disease 2019 (COVID-19) pandemic. We evaluated the volume of CVT hospitalization and in-hospital mortality during the 1st year of the COVID-19 pandemic compared to the preceding year.
Methods:
We conducted a cross-sectional retrospective study of 171 stroke centers from 49 countries. We recorded COVID-19 admission volumes, CVT hospitalization, and CVT in-hospital mortality from January 1, 2019, to May 31, 2021. CVT diagnoses were identified by International Classification of Disease-10 (ICD-10) codes or stroke databases. We additionally sought to compare the same metrics in the first 5 months of 2021 compared to the corresponding months in 2019 and 2020 (ClinicalTrials.gov Identifier: NCT04934020).
Results:
There were 2,313 CVT admissions across the 1-year pre-pandemic (2019) and pandemic year (2020); no differences in CVT volume or CVT mortality were observed. During the first 5 months of 2021, there was an increase in CVT volumes compared to 2019 (27.5%; 95% confidence interval [CI], 24.2 to 32.0; P<0.0001) and 2020 (41.4%; 95% CI, 37.0 to 46.0; P<0.0001). A COVID-19 diagnosis was present in 7.6% (132/1,738) of CVT hospitalizations. CVT was present in 0.04% (103/292,080) of COVID-19 hospitalizations. During the first pandemic year, CVT mortality was higher in patients who were COVID positive compared to COVID negative patients (8/53 [15.0%] vs. 41/910 [4.5%], P=0.004). There was an increase in CVT mortality during the first 5 months of pandemic years 2020 and 2021 compared to the first 5 months of the pre-pandemic year 2019 (2019 vs. 2020: 2.26% vs. 4.74%, P=0.05; 2019 vs. 2021: 2.26% vs. 4.99%, P=0.03). In the first 5 months of 2021, there were 26 cases of vaccine-induced immune thrombotic thrombocytopenia (VITT), resulting in six deaths.
Conclusions
During the 1st year of the COVID-19 pandemic, CVT hospitalization volume and CVT in-hospital mortality did not change compared to the prior year. COVID-19 diagnosis was associated with higher CVT in-hospital mortality. During the first 5 months of 2021, there was an increase in CVT hospitalization volume and increase in CVT-related mortality, partially attributable to VITT.
7.Building the hospital event-based surveillance system in Viet Nam: a qualitative study to identify potential facilitators and barriers for event reporting
Hien Do ; Hien T Ho ; Phu D Tran ; Dang B Nguyen ; Satoko Otsu ; Cindy Chiu de Vá ; zquez ; Tan Q Dang ; Quang D Tran ; Van Anh Pham ; Nanako Mikami ; Masaya Kato
Western Pacific Surveillance and Response 2020;11(3):10-20
Introduction: Hospitals are a key source of information for the early identification of emerging disease outbreaks and acute public health events for risk assessment, decision-making and public health response. The objective of this study was to identify potential facilitators and barriers for event reporting from the curative sector to the preventive medicine sector in Viet Nam.
Methods: In 2016, we conducted 18 semi-structured, in-depth interviews, as well as nine focus group discussions, with representatives from the curative and preventive medicine sectors in four provinces. We transcribed the interviews and focus group discussions and used thematic analysis to identify the factors that appeared to affect public health event reporting.
Results: We identified five major themes. First, the lack of a legal framework to guide reporting meant hospital staff relied on internal procedures that varied from hospital to hospital, which sometimes delayed reporting. Second, participants stated the importance of an enabling environment, such as leadership support and having focal points for reporting, to facilitate reporting. Third, participants described the potential benefits of reporting, such as support provided during outbreaks and information received about local outbreaks. Fourth, some challenges prohibited timely reporting such as not perceiving reporting to be the task of the curative sector and hesitancy to report without laboratory confirmation. Finally, limited resources and specialist capacities in remote areas hindered timely detection and reporting of unusual events.
Discussion: This study identified potential opportunities to promote the detection and reporting of unusual events from health-care workers to the public health sector, and thus to improve the overall health security system in Viet Nam.The influenza virus is a respiratory pathogen that is transmitted through respiratory droplets.1 During seasonal influenza epidemics, high attack rates cause a significant public health burden.2 The infection is usually self-limited in young adults but can lead to severe infections in people in high-risk groups, including elderly people (> 65 years old), pregnant women, children aged 6–59 months and adults with chronic illnesses.3
8. Treatment for COVID-19 patients in Vietnam: Analysis of time-to-recovery
Khuong LONG ; Hoang HANH ; Tran HANH ; La QUANG ; Hoang VAN MINH
Asian Pacific Journal of Tropical Medicine 2020;13(9):397-401
To describe the recovery time and related factors among COVID-19 patients in Vietnam. Methods: We used the secondary data obtained from the official database of the Ministry of Health of Vietnam and other public data sources that were available by April 9th, 2020. Cox proportional hazards model was carried out to identify factors related to recovery time among COVID-19 patients. Results: By April 9th, 2020, the cumulative number of COVID-19 cases detected in Vietnam was 255, of which 129 (50.6%) patients had fully recovered. The median recovery time of patients was 17 (95% CI=16-19) days. Older patients had a lower likelihood of recovery (HR=0.98, 95% CI=0.97-0.99, P0.001), whereas patients with a history of international incoming travel had a higher likelihood of recovery (HR=1.57, 95% CI=1.03-2.40, P=0.036). There was no statistically significant difference in the recovery time of patients treated in different hospital settings. Conclusions: More attention is needed for older patients and who did not have international travel history. Patients confirmed with COVID-19 could be treated at local health facilities to avoid unnecessary referrals and burdens to specialized hospitals at the central level.
9.Study Design for the 2016 Baseline Survey of a Health System Strengthening Project in Quoc Oai District, Hanoi, Vietnam
Van Minh HOANG ; Juhwan OH ; Bao Ngoc NGUYEN ; Le Minh DAT ; Jong Koo LEE ; Thi Giang Huong TRAN ; Van Huy NGUYEN ; Seung Pyo LEE ; Kyung Sook BANG ; Youngtae CHO ; Sun Young KIM ; Hwa Young LEE ; Quang Cuong LE ; Narshil CHOI ; Thai Son DINH ; Ngoc Hoat LUU
Journal of Korean Medical Science 2019;34(5):e42-
BACKGROUND: In order to provide essential scientific evidence on the population's health status and social health determinants as well as the current capacity of the health care system in Vietnam to health policy makers and managers, Vietnam Ministry of Health, Hanoi University of Public Health, Hanoi Medical University, and Ho Chi Minh University of Medicine and Pharmacy collaborated with Seoul National University (Korea) and conducted a health system survey in the Quoc Oai district (of Hanoi capital) that represented northern rural Vietnam. METHODS: The study design was a cross-sectional study. The survey covered different topics (more than 200 questions) and was administered in three separate questionnaires: 1) Basic information of all household members; 2) Household characteristics; and 3) Individual characteristics. Socio-demographic characteristics among the households and individuals were collected from 2,400 households sampled by multi-stage cluster sampling method: more than 200 questions. RESULTS: The household size of Quoc Oai was larger than the national average and there was no significant difference in gender composition. In addition, the proportions of pre-elderly, age 55–64, and elderly group (65 years old and over) were higher than the national population statistics. In this context, demographic transition has begun in Quoc Oai. CONCLUSION: This study design description provides the basic information about a baseline survey of a future prospective cohort (as a part of a collaborative project on strengthening the health system in Vietnam) to the prospective data user of this survey.
Aged
;
Cohort Studies
;
Cross-Sectional Studies
;
Delivery of Health Care
;
Family Characteristics
;
Health Policy
;
Humans
;
Methods
;
Pharmacy
;
Population Characteristics
;
Population Dynamics
;
Prospective Studies
;
Public Health
;
Seoul
;
Surveys and Questionnaires
;
Vietnam
10.Tomographic density imaging using modified DF–DBIM approach
Tran Quang HUY ; Nguyen Thi CUC ; Van Dung NGUYEN ; Ton That LONG ; Tran Duc TAN
Biomedical Engineering Letters 2019;9(4):449-465
Ultrasonic computed tomography based on back scattering theory is the most powerful and accurate tool in ultrasound based imaging approaches because it is capable of providing quantitative information about the imaged target and detects very small targets. The duple-frequency distorted Born iterative method (DF–DBIM), which uses density information along with sound contrast for imaging, is a promising approach for imaging targets at the level of biological tissues. With two frequencies f₁ (low) and f₂ (high) through Nf₁ and Nf₂ iterations respectively, this method is used to estimate target density along with sound contrast. The implications of duple-frequency fusion for the image reconstruction quality of density information along with sound contrast based ultrasound tomography have been analyzed in this paper. In this paper, we concentrate on the selection of parameters that is supposed to be the best to improve the reconstruction quality of ultrasound tomography. When there are restraints imposed on simulated scenarios to have control of the computational cost, the iteration number Nf₁ is determined resulting in giving the best performance. The DF–DBIM is only effective if there are a moderate number of iterations, transmitters and receivers. In case that the number of transducers is either too large or too small, a result of reconstruction which is better than that of the single frequency approach is not produced by the implementation of DF–DBIM. A fixed sum N(iter) of Nf₁ and Nf₂ was given, the investigation of simulation results shows that the best value of Nf₁ is [N(iter)/2 − 1]. The error, when applying this way of choosing the parameters, will be normalized with the reduction of 56.11%, compared to use single frequency as used in the conventional DBIM method. The target density along with sound contrast is used to image targets in this paper. It is a fact that low-frequency offers fine convergence, and high-frequency offers fine spatial resolution. Wherefore, this technique can effectively expand DBIM's applicability to the problem of biological tissue reconstruction. Thanks to the usage of empirical data, this work will be further developed prior to its application in reality.
Image Processing, Computer-Assisted
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Methods
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Transducers
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Ultrasonics
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Ultrasonography


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