Jiann-Der Lee

• Ph.D.
• Professor (Full) at Chang Gung University

Background Resting heart rate is a potent predictor of various renal outcomes. However, the decline rate of renal function in ischemic stroke patients is not well defined. We tested the association of heart rate with estimated glomerular filtration rate (eGFR) decline and the composite renal outcomes in patients with recent ischemic stroke. Method...

Background/Objectives: Small-vessel occlusion, previously referred to as lacunar infarcts, accounts for approximately one-third of all ischemic strokes, using an axial diameter of less than 20 mm on diffusion-weighted imaging. However, this threshold may not adequately differentiate small-vessel occlusion from other pathologies, such as branch athe...

Background Branch atheromatous disease (BAD) is a primary cause of early neurological deterioration (END) in penetrating artery occlusion, leading to poor functional outcomes. While it has been proposed to classify BAD under large artery atherosclerosis, uncertainty exists regarding the optimal treatment strategy, including cholesterol-lowering tar...

Background Although elevated heart rate is a risk factor for cardiovascular morbidity and mortality in healthy people, the association between resting heart rate and major cardiovascular risk in patients after acute ischemic stroke remains debated. This study evaluated the association between heart rate and major adverse cardiovascular events after...

A deep convolution network that expands on the architecture of the faster R-CNN network is proposed. The expansion includes adapting unsupervised classification with multiple backbone networks to improve the Region Proposal Network in order to improve accuracy and sensitivity in detecting minute changes in images. The efficiency of the proposed arc...

Introduction: Acute small subcortical infarctions (SSIs) result from occlusions of small penetrating arteries, and the underlying pathological factors can have different clinical implications. The objective of this study was to assess the clinical relevance of acute SSIs based on their sizes and morphologies. Methods: This retrospective case-con...

Background A high resting heart rate (HR) has been associated with an increased risk of diabetes mellitus. This study explored the association between initial in-hospital HR and glycemic control in patients with acute ischemic stroke (AIS) and diabetes mellitus. Methods We analyzed data from 4,715 patients with AIS and type 2 diabetes mellitus enr...

Background: Long-term mortality prediction can guide feasible discharge care plans and coordinate appropriate rehabilitation services. We aimed to develop and validate a prediction model to identify patients at risk of mortality after acute ischemic stroke (AIS). Methods: The primary outcome was all-cause mortality, and the secondary outcome was...

Featured Application Projection-based Augmented Reality System for Medical Applications. Abstract The aim of this paper was to present the development of an Augmented Reality (AR) system which uses a 2D video projector to project a 3D model of blood vessels, built by combining Computed Tomography (CT) slices of a human brain, onto a model of a hum...

Featured Application Investigation into whether and how much AI-based heat-maps can assist radiologists when making diagnoses based on medical images. Abstract In modern medicine, medical imaging technologies such as computed tomography (CT), X-ray, ultrasound, magnetic resonance imaging (MRI), nuclear medicine, etc., have been proven to provide u...

Feature Application A comparison study of the performances of three type of near real-time deep learning networks in the application of surgical instrument detection and recognition. Abstract In various studies, problems with surgical instruments in the operating room are usually one of the major causes of delays and errors. It would be of great h...

In recent years, Image-Guide Navigation Systems (IGNS) have become an important tool for various surgical operations. In the preparations for planning a surgical path, verifying the location of a lesion, etc., it is an essential tool; in operations such as bronchoscopy, which is the procedure for the inspection and retrieval of diagnostic samples f...

Background Previous clinical trials showed a significant difference in efficacy and safety among antiplatelets in acute ischemic stroke (IS). The present study wished to compare the efficacy and safety head-to-head between cilostazol and clopidogrel in chronic IS. Methods This open prospective cohort study recruited chronic IS patients with an ind...

Background Atrial fibrillation (AF) is the most common cardiac rhythm disorder associated with stroke. Increased risk of stroke is the same regardless of whether the AF is permanent or paroxysmal. However, detecting paroxysmal AF is challenging and resource intensive. We aimed to develop a predictive model for AF in patients with acute ischemic str...

Ischemic stroke is the most common type of stroke, and early interventional treatment is associated with favorable outcomes. In the guidelines, thrombolytic therapy using recombinant tissue-type plasminogen activator (rt-PA) is recommended for eligible patients with acute ischemic stroke. However, the risk of hemorrhagic complications limits the us...

Background Post-stroke pneumonia (PSP) has been implicated in the morbidity, mortality, and increased medical costs after acute ischemic stroke. Aim The aim of this study was to develop a prediction model for PSP in patients with acute ischemic stroke. Methods A retrospective, case-control, secondary analysis study was conducted using data for 10...

Background: Reducing hospital readmissions for stroke remains a significant challenge to improve outcomes and decrease healthcare costs. Methods: We analyzed 10,034 adult patients with ischaemic stroke who presented within 24 hours of onset from a hospital-based stroke registry. The risk factors for early return to hospital after discharge were...

By the standard of today’s image-guided surgery (IGS) technology, in order to check and verify the progress of the surgery, the surgeons still require divert their attention from the patients occasionally to check against the display. In this paper, a mixed-reality system for medical use is proposed that combines an Intel RealSense sensor with Micr...

Background Fabry disease is a X‐linked disease, and enzyme‐based screening methods are not suitable for female patients. Methods Totally, 1,000 young stroke patients (18‐55 y/o, 661 with ischemic stroke and 339 with hypertensive intracerebral hemorrhage) were recruited. Sequenom iPLEX assay was used to detect 26 Fabry related mutation genes. The f...

In many surgery assistance systems, cumbersome equipment or complicated algorithms are often introduced to build the whole system. To build a system without cumbersome equipment or complicated algorithms, and to provide physicians the ability to observe the location of the lesion in the course of surgery, an augmented reality approach using an impr...

Objective: In acute ischemic stroke, early neurological deterioration (END) may occur in up to one-third of patients. However, there is still no satisfying or comprehensive predictive model for all the stroke subtypes. We propose a practical model to predict END using magnetic resonance imaging (MRI). Method: Patients with anterior circulation i...

Background and purpose: Additional folic acid (FA) treatment appears to have a neutral effect on reducing vascular risk in countries that mandate FA fortification of food (e.g., USA and Canada). However, it is uncertain whether FA therapy reduces stroke risk in countries without FA food fortification. The purpose of this study was to comprehensive...

Genome-wide association studies (GWAS) can serve as strong evidence in correlating biological pathways with human diseases. Although ischemic stroke has been found to be associated with many biological pathways, the genetic mechanism of ischemic stroke is still unclear. Here, we performed GWAS for a major subtype of stroke—small-vessel occlusion (S...

Causes of death in both ischemic stroke (IS) and hemorrhagic stroke (HS) subtypes are not comprehensively studied. Between 2008 and 2011, we enrolled 11 215 first-ever stroke patients from the Stroke Registry of Chang-Gung Healthcare System and linked these data to the national death registry. The main causes of death in each stroke subtype were as...

White matter hyperintensities (WMHs) include periventricular WMH (pvWMH) and deep WMH. When hyperintensities in the basal ganglia or brainstem are included, the collective term is subcortical hyperintensities. Both WMH and medial temporal lobe atrophy (MTA) are risk factors for cognitive decline. This prospective study enrolled participants aged 50...

Purpose To compare functional magnetic resonance (MR) imaging for language mapping (hereafter, language functional MR imaging) with direct cortical stimulation (DCS) in patients with brain tumors and to assess factors associated with its accuracy. Materials and Methods PubMed/MEDLINE and related databases were searched for research articles publish...

The risks involved in nighttime driving include drowsy drivers and dangerous vehicles. Prominent among the more dangerous vehicles around at night are the larger vehicles which are usually moving faster at night on a highway. In addition, the risk level of driving around larger vehicles rises significantly when the driver’s attention becomes distra...

Background Many studies have determined that dehydration is an independent predictor of outcome after ischemic stroke (IS); however, none have determined if the use of thrombolytic therapy modifies the negative impact of poor hydration. To inform the stroke registry established at our institution, we conducted a retrospective study to determine if...

Ocular recognition is expected to provide a higher flexibility in handling practical applications as oppose to the iris recognition, which only works for the ideal open-eye case. However, the accuracy of the recent efforts is still far from satisfactory at uncontrollable conditions, such as eye blinking which implies any poses of eyes. To address t...

Normally, modeling 3D face is an effective way for pose-invariant recognition, yet its expensive computation significantly discourages potential applications. In this paper, a simple and fully automatic panoramic image based pose-invariant face recognition method is proposed to present excellent accuracy with low complexity. In this study, a face s...

In recent years, wavelet transform has been widely applied in multimedia signal processing and digital watermarking is involved for ensuring security. This study presents a blind wavelet-based watermarking incorporated with the Human Visual System (HVS), which embeds watermarks into detail-subband coefficients. Since imperceptibility is the most si...

The low-density lipoprotein receptor-related protein 1 (LRP1) gene is associated with increased levels of plasma factor VIII (FVIII). We aimed to explore eight functional genetic LRP1 variants for their potential roles in regulating FVIII levels and acute ischemic stroke (AIS). This genetic association study enrolled 192 patients with AIS and 134 c...

Background: Enhancing detection of undiagnosed atrial fibrillation (AF) in hospitalized patients with a recent ischemic stroke is important because of the treatment implications; especially since presence of paroxysmal AF may not be picked up in a single 12-lead electrocardiogram (ECG) test. While several trials have shown improved detection of AF...

It remains unclear whether statin therapy should be applied to ischemic stroke patients with atrial fibrillation. The objective of this study was to clarify whether statin therapy can influence the prognosis in recent ischemic stroke patients with atrial fibrillation. We identified ischemic stroke patients with atrial fibrillation between 2001 and...

The nail provides a functional protection to the fingertips and surrounding tissue from external injuries. The nail plate consists of three layers including dorsal, intermediate, and ventral layers. The dorsal layer consists of compact, hard keratins, limiting topical drug delivery through the nail. In this study, we investigate the application of...

Background: Critical stroke causes high morbidity and mortality. We examined if variables in the early stage of critical stroke could predict in-hospital mortality. Methods: We recruited 611 ischemic and 805 hemorrhagic stroke patients who were admitted within 24 h after the symptom onset. Data were analyzed with independent t test and Chi squar...

Night driving is dangerous already, but when driving near a large vehicle, the danger multiplies. Because the attention of the driver at night could be distracted thus fail to pay attention to dangerously large vehicles, we propose a component for ADAS systems that will help alert the drivers to the presence of large vehicles. This component utiliz...

Despite advances in imaging techniques and detailed examinations to determine the etiology of a stroke, the cause still remains undetermined in about one fourth of all ischemic strokes. The aim of this prospective study was to determine whether perfusion magnetic resonance imaging (MRI) can differentiate cardioembolic stroke from large artery ather...

Mounting evidence shows that hyperhomocysteinemia is a risk factor for cognitive decline. This study enrolled subjects with normal serum levels of B12 and folate and performed thorough neuropsychological assessments to illuminate the independent role of homocysteine on cognitive functions. Participants between ages 50 and 85 were enrolled with Modi...

Transdermal drug-delivery systems (TDDS) have been a growing field in drug delivery because of their advantages over parenteral and oral administration. Recent studies illustrate that microneedles (MNs) can effectively penetrate through the stratum corneum barrier to facilitate drug delivery. However, the temporal effects on skin and drug diffusion...

In this study, a classification scheme, using the features from resting-state functional MRI (rsfMRI) and voxel-based morphometry (VBM), was proposed to discriminate two subtypes of mild cognitive impairment (MCI): amnestic MCI (aMCI) subtypes and dys executive MCI (dMCI) subtypes. More specifically, this scheme employed random forests (RF) algorit...

Introduction: The purpose of this study was to develop a computational method to identify potential predictors for quality of life (QOL) after post stroke rehabilitation. Methods: Five classifiers were trained by five personal factors and nine functional outcome measures by 10-fold cross-validation. The classifier with the highest cross-validated a...

Objective: The aim of this study was to develop a prediction model that integrated various image features and neuropsychological scores to yield a single estimate reflecting the probability of dementia. Method: A total of 130 subjects belong to Normal control group, AD group, and MCI group, were recruited in this study. For these subjects, the mult...

Conventionally, the camera localization for augmented reality (AR) relies on detecting a known pattern within the captured images. In this study, a markerless AR scheme has been designed based on a Stereo Video See-Through Head-Mounted Display (HMD) device. The proposed markerless AR scheme can be utilized for medical applications such as training,...

In this paper, we present a projection-based medical augmented reality (AR) system for craniofacial application. With the aid of image registration and geometrical correction, the deformation of the projected image on a curved surface like cheek or forehead can be successfully recovered. From the experimental result, it is shown that the overlapped...

Error diffusion is an efficient halftone method for mainly being applied on printers. The promising high image quality and processing efficiency endorse it as a popular and competitive candidate in halftoning and multitoning applications. The multitoning is an extension of halftoning, adopting more than two-tone levels for the improvement of the si...

The role played by hemostasis in the pathogenesis of ischemic strokes is still controversial. The activated partial thromboplastin time (APTT) measures the time necessary to generate fibrin from initiation of the intrinsic pathway. In the present study, we looked for a possible association of ischemic strokes with the shortened APTT. The study popu...

This paper presents a real-time automatic obstacle avoidance system using depth information and sonar data. The depth map is provided by Microsoft Kinect and sonar data are obtained from sonar sensors. With fusion of weighted depth information and sonar data, a set of intelligent fuzzy rules are designed to construct a safe path to avoid obstacles...

A vision-based driver assistance system using fuzzy rules to determine whether warnings are necessary is presented. This system is comprised of four cameras, one of which focuses on the driver for estimating the driver’s viewing angle, another focuses on the road ahead for the detection of road condition ahead, and the last two cameras are on both...

This paper described a novel binary method for inhomogeneously lighted fingerprint optical coherence tomography (OCT) images. To reduce the light effect problem, a block size is calculated by the median value of the length values of white pixels between black pixels in the initial binary result and used to rescale the gray values of the input image...

Medical surgery is considered as a difficult technique and needs to be performed by well-trained and experienced medical personnel to complete the procedure. During a complicated surgery, an experienced surgeon at distant can provide sophisticated instruction or guidance to help the operating surgeon when it is necessary. In this study, we have des...

In this paper, a novel highly efficient lossless data hiding scheme is proposed to achieve the goal of hiding secret data into vector quantization (VQ)-compressed images that can be losslessly reconstructed after the secret data is extracted in the decoder. For VQ-compressed images, the index-modifying and the side-match VQ (SMVQ) techniques can be...

In the fourth generation or next generation networks, services of non-real-time variable bit rate (NRT-VBR) and best effort (BE) will dominate over 85% of the total traffic in the networks. In this paper, we study the power saving mechanism of NRT-VBR and BE services for mobile handsets (MHs) to prolong their battery lifetime (i.e., the sustained o...

The problem of front vehicle detection and tracking during the night, unlike during the day, is that the environment provides little visible information with which to use. However, because it is important task which can help drivers at night, we propose a novel algorithm to detect and track by the location of tail lights. Our algorithm calculates t...

Vehicle detection is an important function for any advanced driver assistance systems (ADAS). Due to the restrictions in data collection, most of the detection methods presented in the past few years were based on the assumption of well-lit environments. In this paper, we propose a novel algorithm to detect vehicle in the night time by the location...

This paper presents a real-time and automatic online vision-based surgical instruments recognition system, which can be used for surgical instruments monitoring during surgery or robotic applications. The main processes of this system consist of feature extraction and classification. In feature extraction, the image of surgical instruments placed o...

Focused ultrasound (FUS) can be used to locally and temporally enhance vascular permeability, improving the efficiency of drug delivery from the blood vessels into the surrounding tissue. However, it is difficult to evaluate in real time the effect induced by FUS and to noninvasively observe the permeability enhancement. In this study, speckle-vari...

Rationale and objectives: The primary objective of the current investigation was to characterize white matter integrity in different subtypes of mild cognitive impairment (MCI) using tract-based spatial statistics of diffusion tensor imaging. Materials and methods: The study participants were divided into 4 groups of 30 subjects each as follows:...

A prior work proposed by Chung-Wu considered an edge-based lookup table to obtain good inversed image quality, yet it suffers from some drawbacks in terms of image quality, memory consumption, and complexity. In this correspondence, an improved scheme is proposed to deal with these issues.

This paper describes a novel region segmentation method created to enhance spatial relationships in 3-D optical coherence tomography (OCT) images. To reduce the noise and distortion problems in low-resolution OCT images, previous work used the mean value and an enhanced-fuzzy-c-mean algorithm to cluster pixels in 2-D OCT images and find the edge be...

In this study, a high accuracy fingerprint classification method is proposed to enhance the performance in terms of efficiency for fingerprint recognition system. The recognition system has been considered as a reliable mechanism for criminal identification and forensic for its invariance property, yet the huge database is the key issue to make the...

This study shows the problem of power saving mechanism (PSM) that sleep intervals of uplink (UL) connections do not synchronize with sleep intervals of downlink (DL) connections. That is, the energy of a mobile station (MS) is not really saved if the DL connections are in the sleep mode while the UL connections are in normal mode, and vice versa. T...

In this paper, we present a physical rehabilitation system which is based on Kinect sensor, to assist patients with movement disorders to perform “Tai Chi” exercises at home. By skeletal tracking of Kinect sensor, each movement of the patient is recognized and validated. Patient's movements are compared to the prerecorded movements of coach, and fu...

Background: The purpose of this study was to examine sex dimorphism in water diffusion in the brain throughout the normal aging process by magnetic resonance imaging. Methods: Diffusion-weighted images covering the majority of the brain were acquired from 77 healthy participants. Both the mean water diffusivity and diffusion kurtosis were calculate...

Halitosis affects people of all ages. Among hospitalized patients, oral care includes toothbrushing and mouth rinses. Tongue cleaning is not included in most guidelines or nursing education curricula. The aim of this study was to compare the effectiveness of two types of oral care, toothbrushing alone and toothbrushing plus tongue cleaning, on hali...

A semi-integrated system for driver assistance and pedestrian safety is presented. This system is composed of a single camera which focuses on the driver for picking up visual cues and a stereo rig that focus on the road ahead for the detection of road obstructions and pedestrians. While the car is in motion, the driver's viewing direction is obtai...

In this study, a local contrast enhancement method, namely Parametric-Oriented Histogram Equalization (POHE), is proposed to effectively yield enhanced results. In general, the grayscale distribution of a specific region in an image can be modeled with a kernel function such as the Gaussian, and thus the corresponding estimated cumulative distribut...

Focused ultrasound (FUS) is a recently discovered noninvasive technique for local and temporal enhancement of vascular permeability, which facilitates drug delivery from the vessels into the surrounding tissue. However, exposure to FUS at a high intensity may cause permanent damage. To investigate the effects of the FUS treatment on blood vessels,...

Look-Up Table (LUT) halftoning is an efficient way to construct halftone images, and approximately simulate the dot distribution of the learned halftone image set. In this study, a general mechanism named Multiple Look-Up Table (MLUT) halftoning is proposed to generate the halftones of Direct Binary Search (DBS), while the high efficient characteri...

This paper proposed a novel gender classification system based on selected texture-based features and Support Vector Machine (SVM) classifier. In this study, t-test is applied as a feature selection technique to select significant features. Firstly, we extract texture-based features comprising Local Binary Patterns (LBP) and Histogram of Oriented G...

For a real driver assistance system, the weather, driving speed, and background could affect the accuracy of obstacle detection. In the past, only a few studies covered all the different weather conditions and almost none of them had paid attention to the safety at vehicle lateral blind spot area. So, this paper proposes a hybrid scheme for pedestr...

In this paper, we present a Kinect-based rehabilitation system to assist patients with movement disorders by performing the "seated Tai Chi" exercises at home. With this physical rehabilitation system, we can evaluate whether patients achieve rehabilitation results correctly or not. By using skeletal tracking of Microsoft Kinect sensor, each gestur...

This paper describes a novel region segmentation method designed to avoid complications of the threshold process used in traditional segmentation methods in 2-D optical coherence tomography (OCT) images. Analysis of the layers and regions in OCT images is used to diagnose the presence of cancer and identify the stage of the cancer if present. Howev...

In this paper, a novel reversible data hiding scheme is presented to achieve the goals of hiding secret data into a Side-Match Vector Quantization (SMVQ) compressed image and lossless reconstruction of the original cover image. The SMVQ prediction is applied to a Vector Quantization (VQ) compressed image to yield the SMVQ compressed image. Distribu...

In this study, an optical coherence tomography (OCT) system is implemented for the noninvasive characterization of photothermolysis in human skin induced by ablative fractional lasers (AFLs) and non-ablative fractional lasers (NAFLs). With OCT imaging, microthermal zones (MTZs) induced by fractional lasers can be noninvasively visualized, and the s...

This paper described a novel region segmentation method to avoid difficulties of the threshold process used in traditional segmentation methods in 2-D optical coherence tomography (OCT) images. The speckle effect and diffusion problems make traditional image processing methods such as Canny edge and Otsu methods fail on finding layers and region ed...

Optical coherence tomography (OCT) has been demonstrated to be a powerful tool for noninvasive, real-time oral cancer diagnosis. However, in previous reports, OCT has still been found to be difficult to use in the diagnosis of oral precancerous stages, including mild dysplasia and moderate dysplasia. In clinical applications, early diagnosis and tr...

Alzheimer's disease (AD) is a neurodegenerative disease, usually diagnosed by neuropsychological tests, and excluded from other cerebral diseases by brain images. An electroencephalogram (EEG) provides a means of disclosing the reduced functional couplings between brain regions that occurs with AD. In the present study, 16 probable AD patients and...

Data hiding is one of the protective techniques for authentication or secret communication through a public and open channel such as the Internet. In this study, a novel lossless data hiding by embedding secret data into a Vector Quantization (VQ)-compressed image is proposed to achieve secret communication and data compression simultaneously. The...

Background: Albuminuria [urine albumin-creatinine ratio (UACR) ≥ 30 mg/g] and low estimated glomerular filtration rate (eGFR < 60 ml/min per 1.73 m ² ) have been separately associated with poor short-intermediate term outcomes after an index stroke. However, few studies have assessed the impact of both these indices of kidney dysfunction in the sam...

The identification of potential predictors for motor outcome after rehabilitation helps underscore the factors that may affect treatment outcomes and target individuals who benefit the most from the therapy. In this study, we addressed and utilized a classifier to identify the potential predictors for motor performance outcome for patients with str...

In this study, an MRI-based classification framework was proposed to distinguish the patients with AD and MCI from normal participants by using multiple features and different classifiers. First, we extracted features (volume and shape) from MRI data by using a series of image processing steps. Subsequently, we applied principal component analysis...

A novel reversible data-hiding scheme is proposed to embed secret data into a side-matched-vector-quantization- (SMVQ-) compressed image and achieve lossless reconstruction of a vector-quantization- (VQ-) compressed image. The rather random distributed histogram of a VQ-compressed image can be relocated to locations close to zero by SMVQ prediction...

In many medical image-guided navigation systems (IGNS), image-to-patient registration plays an important part for applying reliable anatomical information mapping and spatial guidance. In this study, we propose a totally non-contact image-to-patient registration technique using kinect sensor and an ICP-based (Iterative Closest Point-based) registra...

In cranioplasty, neurosurgeons use bone grafts to repair skull defects. To ensure the protection of intracranial tissues and recover the original head shape for aesthetic purposes, a custom-made pre-fabricated prosthesis must match the cranial incision as closely as possible. In our previous study (Liao et al. in Med Biol Eng Comput 49:203-211, 201...