VLDB 2026 Research / reviewers in the wild / expert
M. Ali Nasseri
dblp:143/3784 · also Mohammad Ali Nasseri
· DBLP profile ↗
28ranked-venue papers
0as first author
22since 2021 · last 2026
0000-0002-9764-5731ORCID · verified
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 17 · 14 since 2021Systems, architecture and hardware · 17 · 14 since 2021Applied, interdisciplinary, general and emerging computing · 11 · 8 since 2021Graphics, computer vision, multimedia, augmented reality and games · 4 · 2 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Decoding the surgical scene: A scoping review of scene graphs in surgeryabstractAs surgical AI transitions from pixel-level detection to complex reasoning, Scene Graphs (SGs) offer the structured, relational representations necessary to decode dynamic surgical environments. This PRISMA-ScR-guided scoping review systematically maps the evolving landscape of SG research in surgery, analyzing 52 primary studies to chart applications and methodological shifts. Our analysis reveals rapid growth, yet uncovers a critical 'data divide': internal-view research (e.g., triplet recognition from endoscopic video) accounts for 79% of studies and predominantly uses real-world 2D video, while external-view operating room modeling relies heavily on simulated data. Methodologically, we identify a decisive shift from foundational graph neural networks to specialized foundation models and generative AI, which together now account for approximately 50% of research in 2025. Crucially, our synthesis suggests that Scene Graphs are evolving from simple descriptors into essential 'neuro-symbolic guardrails', providing the structured, verifiable intermediate representation needed to prevent hallucinations in increasingly autonomous Surgical Foundation Models. Despite this promise, a major translational gap remains: none (0/52) of the reviewed studies have proceeded to prospective clinical validation. We conclude that bridging this gap requires moving beyond standard computer vision metrics; we therefore propose the 'Validation Trinity' - prioritizing Semantic Query Success, Latency-Aware Accuracy, and Safety-Critical Recall - as the necessary evaluation framework to bring graph-based surgical AI into clinical practice. Angelo Henriques, Korab Hoxha, Daniel Zapp, Peter C. Issa, Nassir Navab, M. Ali Nasseri |
Medical Image Anal. | 6 |
| 2025 | CLAPS: A CLIP-Unified Auto-Prompt Segmentation for Multi-Modal Retinal ImagingabstractRecent advancements in foundation models, such as the Segment Anything Model (SAM), have significantly impacted medical image segmentation, especially in retinal imaging, where precise segmentation is vital for diagnosis. Despite this progress, current methods face critical challenges: 1) modality ambiguity in textual disease descriptions, 2) a continued reliance on manual prompting for SAM-based workflows, and 3) a lack of a unified framework, with most methods being modalityand task-specific. To overcome these hurdles, we propose CLIP-unified Auto-Prompt Segmentation (CLAPS), a novel method for unified segmentation across diverse tasks and modalities in retinal imaging. Our approach begins by pre-training a CLIP-based image encoder on a large, multi-modal retinal dataset to handle data scarcity and distribution imbalance. We then leverage GroundingDINO to automatically generate spatial bounding box prompts by detecting local lesions. To unify tasks and resolve ambiguity, we use text prompts enhanced with a unique “modality signature” for each imaging modality. Ultimately, these automated textual and spatial prompts guide SAM to execute precise segmentation, creating a fully automated and unified pipeline. Extensive experiments on 12 diverse datasets across 11 critical segmentation categories show that CLAPS achieves performance on par with specialized expert models while surpassing existing benchmarks across most metrics, demonstrating its broad generalizability as a foundation model. Yinzheng Zhao, Junjie Yang 0001, Xiangtong Yao, Quanmin Liang, Shahrooz Faghih Roohi, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
BIBM | 9 |
| 2025 | UOPSL: Unpaired OCT Predilection Sites Learning for Fundus Image Diagnosis AugmentationabstractSignificant advancements in AI-driven multimodal medical image diagnosis have led to substantial improvements in ophthalmic disease identification in recent years. However, acquiring paired multimodal ophthalmic images remains prohibitively expensive. While fundus photography is simple and cost-effective, the limited availability of OCT data and inherent modality imbalance hinder further progress. Conventional approaches that rely solely on fundus or textual features often fail to capture fine-grained spatial information, as each imaging modality provides distinct cues about lesion predilection sites. In this study, we propose a novel unpaired multimodal framework UOPSL that utilizes extensive OCT-derived spatial priors to dynamically identify predilection sites, enhancing fundus imagebased disease recognition. Our approach bridges unpaired fundus and OCTs via extended disease text descriptions. Initially, we employ contrastive learning on a large corpus of unpaired OCT and fundus images while simultaneously learning the predilection sites matrix in the OCT latent space. Through extensive optimization, this matrix captures lesion localization patterns within the OCT feature space. During the fine-tuning or inference phase of the downstream classification task based solely on fundus images, where paired OCT data is unavailable, we eliminate OCT input and utilize the predilection sites matrix to assist in fundus image classification learning. Extensive experiments conducted on 9 diverse datasets across 28 critical categories demonstrate that our framework outperforms existing benchmarks. Yinzheng Zhao, Junjie Yang 0001, Xiangtong Yao, Quanmin Liang, Daniel Zapp, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
BIBM | 9 |
| 2025 | Real-Time Deformation-Aware Control for Autonomous Robotic Subretinal Injection Under iOCT GuidanceabstractRobotic platforms provide consistent and precise tool positioning that significantly enhances retinal microsurgery. Integrating such systems with intraoperative optical coherence tomography (iOCT) enables image-guided robotic interventions, allowing autonomous performance of advanced treatments, such as injecting therapeutic agents into the subretinal space. However, tissue deformations due to tool-tissue interactions constitute a significant challenge in autonomous iOCT-guided robotic subretinal injections. Such interactions impact correct needle positioning and procedure outcomes. This paper presents a novel method for autonomous subretinal injection under iOCT guidance that considers tissue deformations during the insertion procedure. The technique is achieved through real-time segmentation and 3D reconstruction of the surgical scene from densely sampled iOCT B-scans, which we refer to as B5_ scans. Using B5-scans we monitor the position of the instrument relative to a virtual target layer between the ILM and RPE. Our experiments on ex-vivo porcine eyes demonstrate dynamic adjustment of the insertion depth and overall improved accuracy in needle positioning compared to prior autonomous insertion approaches. Compared to a 35% success rate in subretinal bleb generation with previous approaches, our method reliably created subretinal blebs in 90% our experiments. The source code and data used in this study are publicly available on GitHub11https://github.com/demirarikan/virtual-Iayer-retinal-surgery. Demir Arikan, Peiyao Zhang, Michael Sommersperger, Shervin Dehghani, Mojtaba Esfandiari, Russell H. Taylor, M. Ali Nasseri, Peter Gehlbach, Nassir Navab, Iulian Iordachita |
ICRA | 7 |
| 2025 | Pre-Surgical Planner for Robot-Assisted Vitreoretinal Surgery: Integrating Eye Posture, Robot Position and Insertion PointabstractSeveral robotic frameworks have been recently developed to assist ophthalmic surgeons in performing complex vitreoretinal procedures such as subretinal injection of advanced therapeutics. These surgical robots show promising capabilities; however, most of them have to limit their working volume to achieve maximum accuracy. Moreover, the visible area seen through the surgical microscope is limited and solely depends on the eye posture. If the eye posture, trocar position, and robot configuration are not correctly arranged, the instrument may not reach the target position, and the preparation will have to be redone. Therefore, this paper proposes the optimization framework of the eye tilting and the robot positioning to reach various target areas for different patients. Our method was validated with an adjustable phantom eye model, and the error of this workflow was 0.13 ± 1.65 deg (rotational joint around Y axis), -1.40 ± 1.13 deg (around X axis), and 1.80 ± 1.51 mm (depth, Z). The potential error sources are also analyzed in the discussion section. Satoshi Inagaki, Alireza Alikhani, Nassir Navab, Peter C. Issa, M. Ali Nasseri |
ICRA | 5 |
| 2025 | Autonomous Continuous Capsulorhexis Based on a Force-Vision-Guided Robot SystemabstractCapsulorhexis is challenging in cataract surgery, since the size, centering, and circularity of the capsule are important. Those indicators are closely related to the subsequent step of phacoemulsification and the postoperative position of the intraocular lens. It takes 3-5 years for a resident to practice, while the occurrence of deficient capsulorhexis is still inevitable. This paper proposes a robotic system to automate Continuous Curvilinear Capsulorhexis (CCC) in cataract surgery. A typical ophthalmic microscope system and a triaxial force sensor are utilized to guide the robot system with a force-vision method. The constraint of a Remote Center of Motion (RCM) is designed to perform the surgery route. The experimental results on exvivo porcine eyes show our autonomous method can achieve a satisfactory 6 mm capsule. With an average centering deviation below 7.6 % and circularity of 0.993, the consistency of the capsulorhexis is comparable to a surgeon-made one. Hongli Liang, M. Ali Nasseri, Haotian Lin 0001, Kai Huang 0001 |
ICRA | 3 |
| 2025 | Intraoperative Trocar-Based Eyeball Rotation Estimation Using Only 2D Microscope ImagesabstractIn ophthalmic surgery, surgeons or robots manipulate a light probe and an instrument around two separated trocars following sclerotomy to achieve orbital control for eyeball pose adjustment and subsequent surgical tasks referring to microscope frames. However, current methods face significant challenges in directly extracting the eyeball pose from real-time microscope frames due to the limited microscope perspective and the darkened operating room (OR). This paper decomposes eyeball rotations only along the x and y axes. Then, a method of calculating eyeball poses using eyeball geometry and microscopic trocar positions is presented. This method is tested by simulation and a phantom system with current [2.0, 2.8] degree error, providing assistant intraoperative eyeball status in the dark OR with extended method discussions. Junjie Yang 0001, Satoshi Inagaki, Daniel Zapp, Mathias Maier, Peter C. Issa, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
ICRA | 9 |
| 2024 | Extrapolating Prospective Glaucoma Fundus Images through Diffusion in Irregular Longitudinal SequencesabstractThe utilization of longitudinal datasets for glaucoma progression prediction offers a compelling approach to support early therapeutic interventions. Predominant methodologies in this domain have primarily focused on the direct prediction of glaucoma stage labels from longitudinal datasets. However, such methods may not adequately encapsulate the nuanced developmental trajectory of the disease. To enhance the diagnostic acumen of medical practitioners, we propose a novel diffusion-based model to predict prospective images by extrapolating from existing longitudinal fundus images of patients. The methodology delineated in this study distinctively leverages sequences of images as inputs. Subsequently, a time-aligned mask is employed to select a specific year for image generation. During the training phase, the time-aligned mask resolves the issue of irregular temporal intervals in longitudinal image sequence sampling. Additionally, we utilize a strategy of randomly masking a frame in the sequence to establish the ground truth. This methodology aids the network in continuously acquiring knowledge regarding the internal relationships among the sequences throughout the learning phase. Moreover, the introduction of textual labels is instrumental in categorizing images generated within the sequence. The empirical findings from the conducted experiments indicate that our proposed model not only effectively generates longitudinal data but also significantly improves the precision of downstream classification tasks. Junjie Yang 0001, Shahrooz Faghih Roohi, Yinzheng Zhao, Daniel Zapp, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
BIBM | 8 |
| 2024 | KLDD: Kalman Filter based Linear Deformable Diffusion Model in Retinal Image SegmentationabstractAI-based vascular segmentation is becoming increasingly common in enhancing the screening and treatment of ophthalmic diseases. Deep learning structures based on U-Net have achieved relatively good performance in vascular segmentation. However, small blood vessels and capillaries tend to be lost during segmentation when passed through the traditional U-Net downsampling module. To address this gap, this paper proposes a novel Kalman filter based Linear Deformable Diffusion (KLDD) model for retinal vessel segmentation. Our model employs a diffusion process that iteratively refines the segmentation, leveraging the flexible receptive fields of deformable convolutions in feature extraction modules to adapt to the detailed tubular vascular structures. More specifically, we first employ a feature extractor with linear deformable convolution to capture vascular structure information form the input images. To better optimize the coordinate positions of deformable convolution, we employ the Kalman filter to enhance the perception of vascular structures in linear deformable convolution. Subsequently, the features of the vascular structures extracted are utilized as a conditioning element within a diffusion model by the Cross-Attention Aggregation module (CAAM) and the Channel-wise Soft Attention module (CSAM). These aggregations are designed to enhance the diffusion model’s capability to generate vascular structures. Experiments are evaluated on retinal fundus image datasets (DRIVE, CHASE DB1) as well as the 3mm and 6mm of the OCTA-500 dataset, and the results show that the diffusion model proposed in this paper outperforms other methods. Yinzheng Zhao, Junjie Yang 0001, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
BIBM | 6 |
| 2024 | Envibroscope: Real-Time Monitoring and Prediction of Environmental Motion for Enhancing Safety in Robot-Assisted MicrosurgeryabstractSeveral robotic systems have emerged in the recent past to enhance the precision of micro-surgeries such as retinal procedures. Significant advancements have recently been achieved to increase the precision of such systems beyond surgeon capabilities. However, little attention has been paid to the impact of non-predicted and sudden movements of the patient and the environment. Therefore, analyzing environmental motion and vibrations is crucial to ensuring the optimal performance and reliability of medical systems that require micron-level precision, especially in real-life scenarios.To address this challenge, this paper introduces a novel environmental motion analysis system that employs a grid layout with distributed sensing nodes throughout the environment. This system effectively tracks undesired movements (motions) at designated locations and predicts upcoming motions using neural network-based approaches. The outcomes of our experiments exhibit promising prospects for real-time motion monitoring and prediction, which has the potential to form a solid basis for enhancing the automation, safety, integration, and overall efficiency of robot-assisted micro-surgeries. Alireza Alikhani, Satoshi Inagaki, Shervin Dehghani, Mathias Maier, Nassir Navab, M. Ali Nasseri |
ICRA | 6 |
| 2024 | Colibri5: Real-Time Monocular 5-DoF Trocar Pose Tracking for Robot-Assisted Vitreoretinal SurgeryabstractRetinal surgery is a complex medical procedure that requires high precision dexterity to perform delicate instrument maneuvers with sub-millimeter accuracy. Minimizing the manual tremor and achieving precise and repeatable execution of surgical tasks has motivated the development of robotic platforms to overcome the limitations of manual surgery. However, specific tasks, such as instrument insertion through the trocar, are more challenging in robotic surgery than in conventional manual procedures since the robot control is often optimized for navigation inside the eye. This challenges the integration of robotic systems, creating a high cognitive load on the operator and prolonging the surgery time. Moreover, misalignment of the robot’s remote center of motion (RCM) and trocar position during the procedure can lead to excessive forces between the instrument and the trocar, potentially causing patient trauma. Precise and rapid localization of the trocars enables the automation of the insertion procedure and dynamic compensation of eye motion.In this work, we present a real-time marker-less method for 3D pose tracking of trocar, achieved with only a single monocular camera. Our experiments show promising results towards real-time trocar pose estimation and tracking, achieving an average error of 3◦in trocar orientation estimation, with an average processing time of 15 fps. This could serve as a foundation to improve robotic systems’ automation, integration, and efficiency of robotic systems for retinal surgery. The dataset created for this work is made publicly available. Shervin Dehghani, Michael Sommersperger, Mahdi Saleh, Alireza Alikhani, Benjamin Busam, Peter Gehlbach, Iulian Iordachita, Nassir Navab, M. Ali Nasseri |
ICRA | 9 |
| 2024 | Analyzing Accessibility in Robot-Assisted Vitreoretinal Surgery: Integrating Eye Posture and Robot PositionabstractSeveral robotic frameworks have been recently developed to assist ophthalmic surgeons in performing complex vitreoretinal procedures such as subretinal injection. However, in order to intuitively integrate robots into the surgical workflow, it is crucial to emphasize that an accessibility analysis framework for vitreoretinal surgery must be considered as an essential component. Such a framework, ideally, considers the comprehensive factors of the eye anatomy and its positioning, the insertion point, and the initial pose and position of the robot. By combining the mobilization of the eyeball and adjusting the pose and position of the robot, the accessibility of such systems is significantly optimized. At the same time, the accessible-visible area is better and faster matched to the working volume of the robot. This paper presents an analysis of an expansion strategy for the robot’s accessibility and visibility area. The outcomes of this method demonstrate the promising potential to enhance the robot’s accessibility, as evidenced in our analytical and experimental findings from 22.4% to 99.0% of the required working area on an adjustable phantom model. Satoshi Inagaki, Alireza Alikhani, Nassir Navab, Mathias Maier, M. Ali Nasseri |
ICRA | 5 |
| 2024 | Exploring the Needle Tip Interaction Force with Retinal Tissue Deformation in Vitreoretinal SurgeryabstractRecent advancements in age-related macular degeneration treatments necessitate precision delivery into the subretinal space, emphasizing minimally invasive procedures targeting the retinal pigment epithelium (RPE)-Bruch's membrane complex without causing trauma. Even for skilled surgeons, the inherent hand tremors during manual surgery can jeopardize the safety of these critical interventions. This has fostered the evolution of robotic systems designed to prevent such tremors. These robots are enhanced by FBG sensors, which sense the small force interactions between the surgical instruments and retinal tissue. To enable the community to design algorithms taking advantage of such force feedback data, this paper focuses on the need to provide a specialized dataset, integrating optical coherence tomography (OCT) imaging together with the aforementioned force data. We introduce a unique dataset, integrating force sensing data synchronized with OCT B-scan images, derived from a sophisticated setup involving robotic assistance and OCT integrated microscopes. Furthermore, we present a neural network model for image-based force estimation to demonstrate the dataset's applicability. Simon Pannek, Shervin Dehghani, Michael Sommersperger, Peiyao Zhang, Peter Gehlbach, M. Ali Nasseri, Iulian Iordachita, Nassir Navab |
ICRA | 6 |
| 2024 | Shadow-Based 3D Pose Estimation of Intraocular Instrument Using Only 2D ImagesabstractIn ophthalmic surgeries, such as vitreoretinal operations, surgeons rely on imaging systems, primarily microscopes, for real-time instrument monitoring and motion planning. However, novice surgeons struggle to extract 3D instrument positions from 2D microscope frames, necessitating extensive trial-and-error experience with the background that additional imaging modalities such as iOCT remain inaccessible in most operating rooms. Targeting intraocular assessment within the current surgical setup, this paper presents an imagebased pose estimation method to obtain real-time instrument tip positions in a standard 12mm-radius spherical eyeball model, which links floating instruments with on-the-retinal objects based on the intraocular shadowing principle. We validate this estimation method in a Unity simulator and verify its depth estimation capability using a specially designed eyeball phantom. Both simulator and phantom experiments demonstrate an average needle-tip estimation error within [1.0, 2.0] mm using only 2D microscope frames. Junjie Yang 0001, Mathias Maier, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
ICRA | 6 |
| 2024 | An Online Rcm Adjusting System for Robot-Assisted Retinal SurgeriesabstractIn robot-assisted retinal surgery, a Remote Center of Motion (Rcm) allows the surgical instrument to rotate around a distal fixed point without any lateral translations. The Rcm point should be perfectly aligned inside the trocar. Otherwise, unexpected tool translations at the expected remote center will enlarge the force applied to the trocar and consequently result in post-operative complications. Due to the narrow size of the trocar and the lack of real-time detection equipment, the Rcm point is hard to be perfectly located inside the trocar. Even if the Rcm is perfectly aligned, the movement of the tissue around the eyeball could make it inappropriate again. In this paper, inspired by the control strategy of surgeons, an online Rcm adjusting strategy is proposed. Instead of only using one fixed Rcm point, to restrict the force between the surgical tool and the trocar, the proposed strategy adjusts the position of the Rcm point during the motion. The results show our approach significantly reduces the force between the robot end-effector and surgical port by 64.2%. In addition, the results also demonstrate that our approach complies the Rcm trajectories without deforming or spoiling the working space, which is significantly important for obeying surgeon’s instructions in practice. Ting Wang 0028, Huanqi Ni, Yanlin Li 0006, Ruoxi Chen, M. Ali Nasseri, Haotian Lin 0001, Kai Huang 0001 |
IROS | 6 |
| 2024 | Shadow Maintenance for Automatic Light-Probe Control in Ophthalmic Surgeries Using Only 2D informationabstractIn ophthalmic surgeries, the light probe is responsible for providing safe intraocular illumination and ensuring the visibility of the instrument and its shadow as the only available reference for qualitative depth estimation and landing point prediction in fundus microscopic images. To achieve sustainable shadow-based estimation during surgeries, we propose controlling the light probe automatically to limit the shadow position around the instrument tip using only 2D information from the microscope. We also integrate an intensity balancing sub-module to guarantee the normal intensity distribution and the safe depth of light-tip placement. Without motor-based pose coordination between the light probe and the instrument, experiments analyze the performance of our image-based shadow maintenance with only image information under the constraints of RCM and discuss the working volume and segmentation limitations during simulation and real-robot tests. Junjie Yang 0001, Satoshi Inagaki, Daniel Zapp, Mathias Maier, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
IROS | 8 |
| 2024 | Intraocular Reflection Modeling and Avoidance Planning in Image-Guided Ophthalmic SurgeriesabstractIntuitive enhancement of surgical precision in robotic retinal surgery highly depends on the stable acquisition of intraocular imaging data. Such acquisition requires segmenting intraocular components, especially instrument-tip positions, to achieve state estimation and subsequent navigation and motion control. However, intraocular light reflections and glares significantly impact instrument segmentation, state estimation, and subsequent visual servoing in retinal surgery. At the same time, light reflections are among the sources of information for intraoperative navigation. In this work, we propose a method for modeling and optimizing light reflections using microscopy as the standard surgical imaging modality. Beyond optimization, our approach seamlessly integrates the optimized reflection with path planning, strategically circumventing reflection areas and ensuring uninterrupted visibility of instrument tips throughout the surgical procedure. Experiments demonstrate the methodology’s efficacy in avoiding glare affections during eye surgeries. Junjie Yang 0001, Yinzheng Zhao, Daniel Zapp, Mathias Maier, Kai Huang 0001, Nassir Navab, M. Ali Nasseri |
IROS | 8 |
| 2023 | Robotic Navigation Autonomy for Subretinal Injection via Intelligent Real-Time Virtual iOCT Volume SlicingabstractIn the last decade, various robotic platforms have been introduced that could support delicate retinal surgeries. Concurrently, to provide semantic understanding of the surgical area, recent advances have enabled microscope-integrated intraoperative Optical Coherent Tomography (iOCT) with high-resolution 3D imaging at near video rate. The combination of robotics and semantic understanding enables task autonomy in robotic retinal surgery, such as for subretinal injection. This procedure requires precise needle insertion for best treatment outcomes. However, merging robotic systems with iOCT intro-duces new challenges. These include, but are not limited to high demands on data processing rates and dynamic registration of these systems during the procedure. In this work, we propose a framework for autonomous robotic navigation for subretinal injection, based on intelligent real-time processing of iOCT volumes. Our method consists of an instrument pose estimation method, an online registration between the robotic and the iOCT system, and trajectory planning tailored for navigation to an injection target. We also introduce intelligent virtual B-scans, a volume slicing approach for rapid instrument pose estimation, which is enabled by Convolutional Neural Networks (CNNs). Our experiments on ex-vivo porcine eyes demonstrate the precision and repeatability of the method. Finally, we discuss identified challenges in this work and suggest potential solutions to further the development of such systems. Shervin Dehghani, Michael Sommersperger, Peiyao Zhang, Alejandro Martin-Gomez, Benjamin Busam, Peter Gehlbach, Nassir Navab, M. Ali Nasseri, Iulian Iordachita |
ICRA | 8 |
| 2023 | Semantic Virtual Shadows (SVS) for Improved Perception in 4D OCT Guided Surgery
Michael Sommersperger, Shervin Dehghani, Philipp Matten, Kristina Mach, M. Ali Nasseri, Hessam Roodaki, Ulrich Eck, Nassir Navab |
MICCAI (9) | 5 |
| 2023 | Label-Preserving Data Augmentation in Latent Space for Diabetic Retinopathy Recognition
Junjie Yang 0001, Shahrooz Faghih Roohi, Kai Huang 0001, Mathias Maier, Nassir Navab, M. Ali Nasseri |
MICCAI (3) | 7 |
| 2022 | OCT-guided Robotic Subretinal Needle Injections: A Deep Learning-Based Registration ApproachabstractSubretinal injection (SI) is an ophthalmic surgical procedure that allows for the direct injection of therapeutic substances into the subretinal space to treat vitreoretinal disorders. Although this treatment has grown in popularity, various factors contribute to its difficulty. These include the retina’s fragile, nonregenerative tissue, as well as hand tremor and poor visual depth perception. In this context, the usage of robotic devices may reduce hand tremors and facilitate gradual and controlled SI. For the robot to successfully move to the target area, it needs to understand the spatial relationship between the attached needle and the tissue. The development of optical coherence tomography (OCT) imaging has resulted in a substantial advancement in visualizing retinal structures at micron resolution. This paper introduces a novel foundation for an OCT-guided robotic steering framework that enables a surgeon to plan and select targets within the OCT volume. At the same time, the robot automatically executes the trajectories necessary to achieve the selected targets. Our contribution consists of a novel combination of existing methods, creating an intraoperative OCT-Robot registration pipeline. We combined straightforward affine transformation computations with robot kinematics and a deep neural network-determined tool-tip location in OCT. We evaluate our framework’s capability in a cadaveric pig eye open-sky procedure and using an aluminum target board. Targeting the subretinal space of the pig eye produced encouraging results with a mean Euclidean error of 23.8μm. Kristina Mach, Shuwen Wei, Ji Woong Kim, Alejandro Martin-Gomez, Peiyao Zhang, Jin U. Kang, M. Ali Nasseri, Peter Gehlbach, Nassir Navab, Iulian Iordachita |
BIBM | 7 |
| 2022 | ColibriDoc: an Eye-in-Hand Autonomous Trocar Docking SystemabstractRetinal surgery is a complex medical procedure that requires exceptional expertise and dexterity. For this purpose, several robotic platforms are currently under development to enable or improve the outcome of microsurgical tasks. Since the control of such robots is often designed for navigation inside the eye in proximity to the retina, successful trocar docking and insertion of the instrument into the eye represents an additional cognitive effort, and is therefore one of the open challenges in robotic retinal surgery. For this purpose, we present a platform for autonomous trocar docking that combines computer vision and a robotic setup. Inspired by the Cuban Colibri (hummingbird) aligning its beak to a flower using only vision, we mount a camera onto the endeffector of a robotic system. By estimating the position and pose of the trocar, the robot is able to autonomously align and navigate the instrument towards the Trocar Entry Point (TEP) and finally perform the insertion. Our experiments show that the proposed method is able to accurately estimate the position and pose of the trocar and achieve repeatable autonomous docking. The aim of this work is to reduce the complexity of the robotic setup prior to the surgical task and therefore, increase the intuitiveness of the system integration into clinical workflow. Shervin Dehghani, Michael Sommersperger, Junjie Yang 0001, Mehrdad Salehi, Benjamin Busam, Kai Huang 0001, Peter Gehlbach, Iulian Iordachita, Nassir Navab, M. Ali Nasseri |
ICRA | 10 |
| 2020 | Microscope-Guided Autonomous Clear Corneal IncisionabstractClear Corneal Incision, a challenging step in cataract surgery, and important to the overall quality of the surgery. New surgeons usually spend one full year trying to perfect their incision, but even after such rigorous training deficient incisions can still occur. This paper proposes an autonomous robotic system for this self-sealing incision. A conventional ophthalmic microscope system with a monocular camera is utilized to capture the surgical scene, ascertain the robot's position, and estimate depth information. Kinematics with a remote centre of motion (RCM) is designed for a multi-axes robot to perform the incision route. The experimental results on ex-vivo porcine eyes show the autonomous Clear Corneal Incision has a stricter three-plane structure than a surgeon-made incision, which is closer to the ideal incision. Sean J. Bergunder, Duoru Lin, Shengzhi Lin, M. Ali Nasseri, Mingchuan Zhou, Haotian Lin 0001, Kai Huang 0001 |
ICRA | 6 |
| 2020 | Processing-Aware Real-Time Rendering for Optimized Tissue Visualization in Intraoperative 4D OCT
Jakob Weiss, Michael Sommersperger, M. Ali Nasseri, Abouzar Eslami, Ulrich Eck, Nassir Navab |
MICCAI (5) | 3 |
| 2020 | Machine Learning Techniques for Ophthalmic Data Processing: A ReviewabstractMachine learning and especially deep learning techniques are dominating medical image and data analysis. This article reviews machine learning approaches proposed for diagnosing ophthalmic diseases during the last four years. Three diseases are addressed in this survey, namely diabetic retinopathy, age-related macular degeneration, and glaucoma. The review covers over 60 publications and 25 public datasets and challenges related to the detection, grading, and lesion segmentation of the three considered diseases. Each section provides a summary of the public datasets and challenges related to each pathology and the current methods that have been applied to the problem. Furthermore, the recent machine learning approaches used for retinal vessels segmentation, and methods of retinal layers and fluid segmentation are reviewed. Two main imaging modalities are considered in this survey, namely color fundus imaging, and optical coherence tomography. Machine learning approaches that use eye measurements and visual field data for glaucoma detection are also included in the survey. Finally, the authors provide their views, expectations and the limitations of the future of these techniques in the clinical practice. Mhd Hasan Sarhan, M. Ali Nasseri, Daniel Zapp, Mathias Maier, Chris P. Lohmann, Nassir Navab, Abouzar Eslami |
IEEE J. Biomed. Health Informatics | 2 |
| 2019 | Needle Localization for Robot-assisted Subretinal Injection based on Deep Learning
Mingchuan Zhou, Xijia Wang, Jakob Weiss, Abouzar Eslami, Kai Huang 0001, Mathias Maier, Chris P. Lohmann, Nassir Navab, Alois C. Knoll, M. Ali Nasseri |
ICRA | 10 |
| 2018 | Precision Needle Tip Localization Using Optical Coherence Tomography Images for Subretinal InjectionabstractSubretinal injection is a delicate and complex microsurgery, which requires surgeons to inject the therapeutic substance in a pre-operatively defined and intra-operatively updated subretinal target area. Due to the lack of subretinal visual feedback, it is hard to sense the insertion depth during the procedure, thus affecting the results of surgical outcome and hindering the widespread use of this treatment. This paper presents a novel approach to estimate the 3D position of the needle under the retina using the information from microscope-integrated Intraoperative Optical Coherence Tomography (iOCT). We evaluated our approach on both tissue phantom and ex-vivo porcine eyes. Evaluation results show that the average error in distance measurement is 4.7 μm (maximum of 16.5 μm). We furthermore, verified the feasibility of the proposed method to track the insertion depth of needle in robot-assisted subretinal injection. Mingchuan Zhou, Kai Huang 0001, Abouzar Eslami, Hessam Roodaki, Daniel Zapp, Mathias Maier, Chris P. Lohmann, Alois C. Knoll, M. Ali Nasseri |
ICRA | 9 |
| 2017 | Surgical Soundtracks: Towards Automatic Musical Augmentation of Surgical Procedures
Sasan Matinfar, M. Ali Nasseri, Ulrich Eck, Hessam Roodaki, Navid Navab, Chris P. Lohmann, Mathias Maier, Nassir Navab |
MICCAI (2) | 2 |