Vision guided automation for intra-cytoplasmic sperm injection

Biological cell injection is an effective technique in which a foreign material is directly introduced into the target cell. Intracytoplasmic Sperm Injection (ICSI) is a microinjection technique which is used for infertility treatment. In this technique, a single sperm cell is directly injected into an oocyte using micropipettes. The operations in this application are manually controlled by an embryologist and more importantly, this reduces the accuracy, repeatability, and consistency of the operation. Therefore, the full automation is a prerequisite for microinjection operations, particularly in ICSI application. This thesis focuses on enhancing the microinjection procedure by developing vision-guided processes prior to and during the operation. Initially, a vision-controlled technique was proposed to align the injection and holding pipettes in three orthogonal axes which is essential for successful microinjection. To conduct reliable injection, the vibrational displacement of the injection pipette’s tip needs to be evaluated and improved before the operations continue further. A novel vision-based sensor was developed to measure the displacement changes at the tip in three orthogonal axes. By employing the developed vision sensor, the effect of injection speed on vibrational displacement creation was analysed to determine the value of various injection parameters, such as force fluctuation, and penetration force on cell damages. An ultimate automation task is required in microinjection to position the randomly located biological cell within the Petri dish to the system’s field of view. The proposed technique fills a gap in the literature by proposing a real-time cell recognising and positioning system that can be employed with different types of biological cells at various maturation stages, as well as with different microscope types that are being used in microinjection applications

The Role of MEMS in In-Vitro-Fertilization

The assisted reproduction has been considered a viable solution for the infertility of humankind for more than four decades. In-Vitro-Fertilization (IVF) is one of the most successful assisted reproduction techniques, where the reproductive cell of the female partner is fertilized outside of her body. Initially, the IVF process has been conducted manually by an experienced embryologist. However, even with a highly experienced individual, the operation had extremely lower success rates due to the limited control in environmental conditions and the requirement of precise movements. Therefore, to address this technological deficit, the feasibility of the mechatronics devices for IVF procedures has been investigated. Among the different mechatronics concepts, micro-electromechanical system (MEMS) technologies have been gradually attracted to the IVF process and improved its capabilities. The purpose of this paper is to present a brief overview of the role of MEMS technologies in IVF. The article classifies the MEMS technologies in IVF based on their application in order to emphasize its contribution. In addition, the article extensively discusses the state-of-the-art mechatronic techniques utilized in Intracytoplasmic Sperm Injection (ICSI), one of the most popular techniques used in IVF. This review article expects to become extremely beneficial for the engineering researchers new to this field who seek critical information on IVF in simple terms with highlights on the possible advancements and challenges that may emerge in the future

Design and implementation of a vision system for microassembly workstation

Rapid development of micro/nano technologies and the evolvement of biotechnology have led to the research of assembling micro components into complex microsystems and manipulation of cells, genes or similar biological components. In order to develop advanced inspection/handling systems and methods for manipulation and assembly of micro products and micro components, robust micromanipulation and microassembly strategies can be implemented on a high-speed, repetitive, reliable, reconfigurable, robust and open-architecture microassembly workstation. Due to high accuracy requirements and specific mechanical and physical laws which govern the microscale world, micromanipulation and microassembly tasks require robust control strategies based on real-time sensory feedback. Vision as a passive sensor can yield high resolutions of micro objects and micro scenes along with a stereoscopic optical microscope. Visual data contains useful information for micromanipulation and microassembly tasks, and can be processed using various image processing and computer vision algorithms. In this thesis, the initial work on the design and implementation of a vision system for microassembly workstation is introduced. Both software and hardware issues are considered. Emphasis is put on the implementation of computer vision algorithms and vision based control techniques which help to build strong basis for the vision part of the microassembly workstation. The main goal of designing such a vision system is to perform automated micromanipulation and microassembly tasks for a variety of applications. Experiments with some teleoperated and semiautomated tasks, which aim to manipulate micro particles manually or automatically by microgripper or probe as manipulation tools, show quite promising results

High-throughput vertebrate total analysis/screening platform

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.Includes bibliographical references.High-throughput screening (HTS) is seen as one of the most promising technologies to facilitate biomedical studies and pharmaceutical discoveries. Although large varieties of in vitro HTS technologies have opened great opportunities, the speed of improvement has been limited by lack of advanced tools for in vivo screening on whole complex organisms, such as vertebrates. To address this issue, a high-throughput platform as a vertebrate total analysis/screening system (V-TAS) is proposed. This platform consists of two independent parts: an automated imaging system and an automated microinjection system. These two systems are designed for general high-content high-throughput pharmaceutical and genetic screens on whole zebrafish larvae, and therefore, are well-modularized for adapting different situations. Furthermore, to demonstrate the capability of V-TAS, a screen of lipidoid library for biologics delivery on thousands of animals was conducted. Very limited damage to the larvae was shown during the screening. In the end, the author also validated the hits discovered by V-TAS can be applied to more advanced animal models such as rats, and be more predictable than cell-based assays.by Tsung-Yao Chang.Ph.D

Oocyte positional recognition for automatic manipulation in ICSI

Polar body position detection is a necessary process in the automation of micromanipulation systems specifically used in intracytoplasmic sperm injection (ICSI) applications. The polar body is an intracellular structure, which accommodates the chromosomes, and the injection must not only avoid this structure but be at the furthest point away from it. This paper aims to develop a vision recognition system for the recognition of the oocyte and its polar body in order to be used to inform the automated injection mechanism to avoid the polar body. The novelty of the paper is its capability to determine the position and orientation of the oocyte and its polar body. The gradient-weighted Hough transform method was employed for the detection of the location of the oocyte and its polar body. Moreover, a new elliptical fitting method was employed for size measurement of the polar bodies and oocytes for the allowance of morphological variance of the oocytes and their polar bodies. The proposed algorithm has been designed to be adaptable with typical commercial inverted microscopes with different criteria. The successful experimental results for this algorithm produce maximum errors of 5% for detection and 10% for reporting respectively

Microdevices and Microsystems for Cell Manipulation

Microfabricated devices and systems capable of micromanipulation are well-suited for the manipulation of cells. These technologies are capable of a variety of functions, including cell trapping, cell sorting, cell culturing, and cell surgery, often at single-cell or sub-cellular resolution. These functionalities are achieved through a variety of mechanisms, including mechanical, electrical, magnetic, optical, and thermal forces. The operations that these microdevices and microsystems enable are relevant to many areas of biomedical research, including tissue engineering, cellular therapeutics, drug discovery, and diagnostics. This Special Issue will highlight recent advances in the field of cellular manipulation. Technologies capable of parallel single-cell manipulation are of special interest

Human Blastocyst\u27s Zona Pellucida Segmentation via Boosting Ensemble of Complementary Learning

Characteristics of Zona Pellucida (ZP), particularly its thickness, is a key indicator of human blastocyst (day-5embryo) quality. Therefore, ZP segmentation is an important step towards achieving automatic embryo qualityassessment. In this paper, a novel approach based on boosting ensemble of hybrid complementary learning isproposed to segment Zona Pellucida in human blastocyst images. First, an inner-ZP localization method isproposed to separate the ZP from the heavily textured area inside a blastocyst. Then, a deep Hierarchical NeuralNetwork (HiNN) is proposed to segment ZP area. The hierarchical nature of the proposed network enableslearning features with respect to their spatial location in the embryo. Finally, a Self-supervised Image-SpecificRefinement (SISR) strategy is proposed as a complementary step to boost the performance. The proposed systemis a hybrid approach in the sense that the HiNN learns the intra-correlation among images, while the SISR takesinto account the inter-correlation within the query image. Experimental results confirm that the proposed method is capable of identifying ZP area with average Precision, Recall, Accuracy and Jaccard Index of 85.2%, 92.0%, 95.6% and 78.1%, respectively. The proposed HiNN system outperforms state of the art by 4.9% in Precision, 11.2% in Recall, 3.6% in Accuracy and 10.7% in Jaccard Index

Dictyostelium discoideum as a model for the evaluation of teratogenic compounds

Before new chemicals can be put on the market, they must be evaluated for toxicological safety. Evaluating the safety of new chemicals, for either medical, cosmetic or environmental application, is tightly regulated by worldwide legislation. A critical aspect of toxicity evaluation is developmental and reproductive toxicity (DART) testing. Traditionally, DART testing has been conducted in vivo in mammalian model systems. In fact, current EU DART testing guidelines accounts for the majority of animals used and the financial costs of new compound compliance testing. Therefore, because of the need to reduce the financial and animal costs associated with DART testing, there is a growing demand for new alternative model systems for toxicity evaluation. Dictyostelium discoideum is a eukaryotic amoeba which due to its unique developmental cycle has the potential to serve as a non-animal alternative model in DART testing. However, for a new alternative model to be proven effective it must allow for high-throughput screening, whilst maintaining biological complexity; allowing developmental toxicity results to be predictive of mammalian systems. To address these concerns, we developed new high-throughput D. discoideum growth and developmental toxicity assays. We use the assays to characterise toxicity across a broad range of test compounds, thereby revealing a significant relationship between D. discoideum and mammalian toxicity values. Our data demonstrates that D. discoideum has the biological complexity necessary to be predictive of mammalian toxicity. We further assess whether D. discoideum could be used to genetically characterise developmentally toxic compounds. Using next generation functional genomic screens, we show how the developmentally toxicity compounds, lithium and VPA can be globally genetically phenotyped. Using this genetic phenotyping approach, we were also able to identify the biological targets and processes that mediate lithium and VPA toxicity. Together, these studies illustrate the potential of D. discoideum to be developed as a new alternative model in DART testing

Computer vision for sequential non-invasive microscopy imaging cytometry with applications in embryology

Many in vitro cytometric methods requires the sample to be destroyed in the process. Using image analysis of non-invasive microscopy techniques it is possible to monitor samples undisturbed in their natural environment, providing new insights into cell development, morphology and health. As the effect on the sample is minimized, imaging can be sustained for long un-interrupted periods of time, making it possible to study temporal events as well as individual cells over time. These methods are applicable in a number of fields, and are of particular importance in embryological studies, where no sample interference is acceptable. Using long term image capture and digital image cytometry of growing embryos it is possible to perform morphokinetic screening, automated analysis and annotation using proper software tools. By literature reference, one such framework is suggested and the required methods are developed and evaluated. Results are shown in tracking embryos, embryo cell segmentation, analysis of internal cell structures and profiling of cell growth and activity. Two related extensions of the framework into three dimensional embryo analysis and adherent cell monitoring are described