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PubMed2006

Postoperative adjuvant treatment for pineal parenchymal tumour of intermediate differentiation.

Pineal parenchymal tumour of intermediate differentiation (PPTID) in adults is rare and a treatment strategy for this condition has not yet been established. We present a case of an elderly patient treated with postoperative adjuvant therapy using radio- and chemotherapy. This 60-year-old man presented with a 3-month history of memory disturbance, gait instability and double vision. Computed tomography and magnetic resonance imaging demonstrated a mass in the pineal region that suggested a malignant tumour. Partial removal of the tumour was undertaken via the right occipital transtentorial approach. The histological diagnosis was PPTID. Postoperative radio- and chemotherapy were administered, with a good response. Little is known about the clinical behaviour of PPTID in adults. Our treatment plan indicates one effective option for the management of such tumours.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2026

Automated CEAP Classification of Venous Duplex Reports Using Multimodal Artificial Intelligence.

OBJECTIVE: To develop and internally validate a prototype multimodal artificial intelligence system for automated CEAP (Clinical, Etiological, Anatomical and Pathophysiological) classification of venous duplex ultrasound (VDUS) reports, integrating natural language processing of free-text components with computer vision analysis of hand-drawn anatomical diagrams. METHODS: Single centre retrospective observational study using routinely collected clinical data. One thousand consecutive venous duplex ultrasound reports from Cambridge University Hospitals NHS Foundation Trust, UK (July 2024 - May 2025) were labelled according to the CEAP classification, excluding the Etiological component, which could not be reliably determined from duplex reports alone. Transfer learning was applied using ClinicalBERT for text and MobileNetV3 for diagrammatic data. Clinical classes were predicted from request line text. Text- and image-based pathophysiological models were developed for four anatomical territories (Great Saphenous Vein, Small Saphenous Vein, Deep system, Perforators), combined using late fusion with probability averaging. RESULTS: The clinical CEAP model achieved accuracy of 0.91, macro-F1 of 0.82, and macro-AUC of 0.98. Pathophysiological prediction varied, with text models broadly outperforming image models. Fusion yielded heterogeneous benefits, improving SSV performance but reducing Deep system accuracy. The performance of the final pathophysiological CEAP fusion models varied across anatomical territories: accuracy ranged from 0.70-0.92 and macro-AUC from 0.80-0.92. CONCLUSION: This study demonstrates the feasibility of automated CEAP classification from VDUS reports. Despite class imbalance affecting minority class predictions, the strong discriminatory performance validates this multimodal ML model for extracting clinically meaningful information from real-world data. This approach offers potential, pending external validation, to streamline vascular services through automated triage and guideline-compliant decision making.

Artificial intelligence↗

PubMed2026

Effectiveness of an AI-based home exercise app for rehabilitation of rotator cuff-related shoulder pain: A randomized controlled trial.

BACKGROUND: Rotator cuff-related shoulder pain contributes to disability and healthcare use. Although therapeutic exercise is first-line treatment, limited supervision and adherence may reduce its effectiveness; digital rehabilitation with real-time feedback may address these limitations. OBJECTIVES: To evaluate the effectiveness of adding a digital rehabilitation program to standard physiotherapy on pain, function, fear-avoidance beliefs, and healthcare utilization. DESIGN: Single-center, assessor-blinded, randomized controlled trial with two parallel groups. METHOD: Forty-six adults (mean age 59 years) with rotator cuff-related shoulder pain were randomized to 12 weeks of conventional physiotherapy or physiotherapy plus an AI-based digital rehabilitation program using computer vision for real-time feedback and performance monitoring. Outcomes were assessed at baseline and at 2, 4, and 12 weeks. Pain intensity (NPRS) was primary outcome; secondary outcomes included upper limb function (QuickDASH), fear-avoidance beliefs (FABQ), and post-intervention healthcare utilization. Analyses followed an intention-to-treat approach. RESULTS: Pain reduction exceeded the MCID (1.3) at 4 and 12 weeks. Between-group differences favoured the intervention at Weeks 2 and 4 (MD -0.7; 95% CI -1.13 to -0.14 and MD -1.01; 95% CI -1.8 to -0.2, respectively). Upper limb function improved more at Week 4 (MD -7.3; 95% CI -12.3 to -2.2). FABQ scores decreased more at Week 12 (MD -7.6; 95% CI -14 to -0.5). Fewer participants in the experimental group required post-intervention healthcare (3 vs 10; p = 0.02). CONCLUSION: Adding AI-based home exercise app to conventional treatment improve pain and may improve function and reduce healthcare utilization in rotator cuff-related shoulder pain.

Humans↗

PubMedDate not supplied

Hue geometry and horizontal connections.

Primate visual systems support an elaborate specialization for processing color information. Concentrating on the hue component, we observe that, contrary to Mondrian-like assumptions, hue varies in a smooth manner for ecologically important natural imagery. To represent these smooth variations, and to support those information processing tasks that utilize hue, a piecewise smooth hue field is postulated. The geometry of hue-patch interactions is developed analogously to orientation-patch interactions in texture. The result is a model for long-range (horizontal) interactions in the color domain, the power of which is demonstrated on a number of examples. Implications for computer image processing, computer vision, visual neurophysiology and psychophysics are discussed.

Animals↗

PubMed2005

Effects of clozapine plus lamotrigine on phencyclidine-induced hyperactivity.

There is growing evidence from both uncontrolled and controlled clinical studies that lamotrigine (LTG) significantly augments clozapine (CLZ) in the treatment of refractory schizophrenia (RS) [Dursun, S.M., McIntosh, D., Milliken, H., 1999. Clozapine plus lamotrigine in treatment-resistant schizophrenia. Arch. Gen. Psychiatry 56, 950; Dursun, S.M., Deakin, J.F.W., 2001. Augmenting antipsychotic treatment with lamotrigine or topiramate in patients with treatment-resistant schizophrenia: a naturalistic case-series outcome study. J. Psychopharmacol. 15, 297-301; Tiihonen, J., Hallikainen, T., Ryynanen, O.P., Repo-Tiihonen, E., Kotilinen, I., Eronen, M., Toivonen, P., Wahlbeck, K., Putkonen, A., 2003. Lamotrigine in treatment-resistant schizophrenia; a randomized placebo-controlled cross over trial. Biol. Psychiatry 54, 1241-1248; Kremer, I., Vass, A., Gorelik, I., Bar, G., Blanaru, M., Javitt, D.C., Heresco-Levy, U., 2004. Placebo-controlled trial of lamotrigine added to conventional and atypical antipsychotics in schizophrenia. Biol. Psychiatry. 56, 441-446]. However, the precise mechanism of action of this synergistic augmentation between clozapine and lamotrigine remains unclear. Therefore, the goal of this research is to explore the mechanism of action of this synergistic interaction between CLZ and LTG, utilizing a pharmacological animal model of schizophrenia by using phencyclidine (PCP). The effects of CLZ plus LTG were assessed by measuring PCP-induced hyper-locomotion and stereotyped behaviours in rats. Adult male rats (250-300 g) were pre-treated via intra-peritoneal (i.p.) injection with vehicle or drug 30 min before a PCP (5 mg/kg) or saline challenge. The behaviours were recorded and analysed for a 90-min period using the Etho Vision-computer based system. PCP produced hyper-locomotion, which was maximal at 30 min. LTG (10 mg/kg) significantly increased hyperlocomotion induced with PCP. However, a combination treatment of CLZ (5 mg/kg) plus LTG (10 mg/kg) significantly blocked the potentiation of PCP-induced hyper-locomotion observed with LTG (10 mg/kg) alone. Furthermore, the PCP-induced locomotion in the combination CLZ plus LTG-treated rats was significantly decreased when compared to vehicle. Therefore, LTG at doses that do not induce ataxia enhanced PCP-induced hyper-locomotion in rats, whereas the combination of LTG and CLZ significantly decreased PCP-induced hyper-locomotion consistent with clinical data.

Analysis of Variance↗

PubMed2005

Tracking multiple targets with multifocal attention.

Attention allows us to monitor objects or regions of visual space and select information from them for report or storage. Classical theories of attention assumed a single focus of selection but many everyday activities, such as video games, navigating busy intersections, or watching over children at a swimming pool, require attention to multiple regions of interest. Laboratory tracking tasks have indeed demonstrated the ability to track four or more targets simultaneously. Although the mechanisms by which attention maintains contact with several targets are not yet established, recent studies have identified several characteristics of the tracking process, including properties defining a 'trackable' target, the maximum number of targets that can be tracked, and the hemifield independence of the tracking process. This research also has implications for computer vision, where there is a growing demand for multiple-object tracking.

Attention↗

PubMed2005

Edges and bars: where do people see features in 1-D images?

There have been two main approaches to feature detection in human and computer vision--based either on the luminance distribution and its spatial derivatives, or on the spatial distribution of local contrast energy. Thus, bars and edges might arise from peaks of luminance and luminance gradient respectively, or bars and edges might be found at peaks of local energy, where local phases are aligned across spatial frequency. This basic issue of definition is important because it guides more detailed models and interpretations of early vision. Which approach better describes the perceived positions of features in images? We used the class of 1-D images defined by Morrone and Burr in which the amplitude spectrum is that of a (partially blurred) square-wave and all Fourier components have a common phase. Observers used a cursor to mark where bars and edges were seen for different test phases (Experiment 1) or judged the spatial alignment of contours that had different phases (e.g. 0 degrees and 45 degrees ; Experiment 2). The feature positions defined by both tasks shifted systematically to the left or right according to the sign of the phase offset, increasing with the degree of blur. These shifts were well predicted by the location of luminance peaks (bars) and gradient peaks (edges), but not by energy peaks which (by design) predicted no shift at all. These results encourage models based on a Gaussian-derivative framework, but do not support the idea that human vision uses points of phase alignment to find local, first-order features. Nevertheless, we argue that both approaches are presently incomplete and a better understanding of early vision may combine insights from both.

Contrast Sensitivity↗

PubMed2006

The rapid extraction of numeric meaning.

Several kinds of statistical properties can be rapidly extracted from visual displays (e.g., luminance and roughness, Olive, A., & Torralba, A. (2001). Modeling the shape of the scene: a holistic representation of the spatial envelope. International Journal of Computational Vision, 42, 145-175). Here, we investigate whether this phenomenon extends to meaning contained in Arabic numerals. Observers were shown brief displays containing two sets of numerals and asked to determine which contained the largest average value. Comparisons were made more quickly and accurately between displays of digits than between displays of letters and shapes; this effect could not be attributed to task instructions. When numeric meaning could be used in a classification task, performance was better for digits than for letters, but when numeric meaning could not be used as a basis of classification, performance was approximately equal across stimulus types, suggesting that numeric meaning is rapidly extracted only when it is task-relevant. The digit advantage was eliminated with unlimited viewing time, suggesting that this process is used when counting is not possible. Dual-task methodology revealed that this process requires limited-capacity attentional resources.

Adult↗

PubMed1999

Averaging expectancies and perceptual experiences in the assessment of quality.

This study examines whether people integrate expectancy information with perceptual experiences when evaluating the quality of consumer products. In particular, we investigate the following three questions: (1) Are expectancy effects observed in the evaluation of consumer products? (2) Can these effects be viewed in cognitive processing terms? (3) Can a mathematical model based on the averaging of attribute information describe the effects? Participants in two experiments blindly evaluated (with the product names removed) consumer products from six sensory modalities: vision (computer printer output), tactile (paper towels), olfaction (men's cologne), taste (corn chips), auditory (audio cassette tapes), and tactile/medicinal (hand lotion). Participants in both experiments were asked to: (1) rate the overall quality of the product given arbitrary quality labels (High Quality, Medium Quality, or Low Quality); (2) rate the overall quality of the product without the labels, and (3) estimate the scale values for the quality labels alone. Group results revealed main effects of the quality labels in all product categories. The pattern of results could be described by an averaging model based on Information Integration Theory. These results have implications for placebo effects in consumer behavior and decision making.

Attitude↗

PubMed1998

Recovery of 3D volume from 2-tone images of novel objects.

In 2-tone images (e.g., Dallenbach's cow), only two levels of brightness are used to convey image structure-dark object regions and shadows are turned to black and light regions are light regions are turned white. Despite a lack of shading, hue and texture information, many 2-tone images of familiar objects and scenes are accurately interpreted, even by naive observers. Objects frequently appear fully volumetric and are distinct from their shadows. If perceptual interpretation of 2-tone images is accomplished via bottom-up processes on the basis of geometrical structure projected to the image (e.g., volumetric parts, contour and junction information) novel objects should appear volumetric as readily as their familiar counterparts. We demonstrate that accurate volumetric representations are rarely extracted from 2-tone images of novel objects, even when these objects are constructed from volumetric primitives such as generalized cones (Marr, D., Nishihara, H.K., 1978. Proceedings of the Royal Society London 200, 269-294; Biederman, I. 1985. Computer Vision, Graphics, and Image Processing 32, 29-73), or from the rearranged components of a familiar object which is itself recognizable as a 2-tone image. Even familiar volumes such as canonical bricks and cylinders require scenes with redundant structure (e.g., rows of cylinders) or explicit lighting (a lamp in the image) for recovery of global volumetric shape. We conclude that 2-tone image perception is not mediated by bottom-up extraction of geometrical features such as junctions or volumetric parts, but may rely on previously stored representations in memory and a model of the illumination of the scene. The success of this top-down strategy implies it is available for general object recognition in natural scenes.

Adult↗

PubMed2003

Explicit calibration method and specific device designed for stereoradiography.

The three-dimensional geometry of the human spine is noteworthy information that can be obtained by stereoradiographic methods. These methods are based on the identification of anatomical structures in several views which are obtained by rotation of a patient standing on a turntable. Calibration algorithms for computer vision or photogrammetry are well documented, but they generally yield calibration devices which are cumbersome for the use in clinical stereoradiography. This paper presents a calibration method adapted to a two-view stereoradiography calibration (frontal and lateral incidences) and based on a simplified geometric modeling of the radiological environment. The a priori knowledge yields four calibration equations related to the vertical and horizontal planes of both views, leading to a specific calibration procedure and device. Moreover this device is attached to the stereoradiographic system (directly integrated on the turntable) in order to facilitate clinical applications. A validation was performed on 26 dried lumbar vertebrae in order to evaluate clinical situation. The mean accuracy of the stereoradiographic reconstruction was 1.2mm.

Aged↗

PubMed2001

Orientation processing mechanisms revealed by the plaid tilt illusion.

The tilt after-effect (TAE) and tilt illusion (TI) have revealed a great deal about the nature of orientation coding of 1-dimensional (1D) lines and gratings. Comparatively little research however has addressed the mechanisms responsible for encoding the orientation of 2-dimensional (2D) plaid stimuli. A multi-stage model of edge detection has recently been proposed [Georgeson, M. A. (1998) Image & Vision Computing, 16(6-7), 389-405] to account for the perceived structure of a plaid stimulus that incorporates extraction of the zero-crossings (ZCs) of the plaid. Data is presented showing that the ZCs of a plaid inducing stimulus can interact with vertical grating test stimulus to induce a standard tilt illusion. However, by considering the second-order structure of a plaid rather than ZCs, it was shown that the perceived orientation of the vertical test grating results from the combination of orientation illusions due to the first- and second-order components of an inducing plaid. The data suggest that the mechanisms encoding the orientation of second-order contours are similar to, and interact directly with, those that encode first-order contours.

Contrast Sensitivity↗

PubMed2001

AI-based algorithms for protein surface comparisons.

Many current methods for protein analysis depend on the detection of similarity in either the primary sequence, or the overall tertiary structure (the Calpha atoms of the protein backbone). These common sequences or structures may imply similar functional characteristics or active properties. Active sites and ligand binding sites usually occur on or near the surface of the protein; so similarly shaped surface regions could imply similar functions. We investigate various methods for describing the shape properties of protein surfaces and for comparing them. Our current work uses algorithms from computer vision to describe the protein surfaces, and methods from graph theory to compare the surface regions. Early results indicate that we can successfully match a family of related ligand binding sites, and find their similarly shaped surface regions. This method of surface analysis could be extended to help identify unknown surface regions for possible ligand binding or active sites.

Algorithms↗

PubMed2002

Combining biometric and symbolic models for customized, automated prosthesis design.

In a previous paper [Artif. Intell. Med. 5 (1993) 431] we described RaPiD, a knowledge-based system for designing dental prostheses. The present paper discusses how RaPiD has been extended using techniques from computer vision and logic grammars. The first employs point distribution and active shape models (ASMs) to determine dentition from images of casts of patient's jaws. This enables a design to be customized to, and visualised against, an image of a patient's dentition. The second is based on the notion of a path grammar, a form of logic grammar, to generate a path linking an ordered sequence of subcomponents. The shape of an important and complex prosthesis component can be automatically seeded in this fashion. Combining these models now substantially automates the design process, beginning with a photograph of a dental cast and ending with an annotated and validated design diagram ready to guide manufacture.

Anthropometry↗

PubMed2000

Automatic recognition of biological shapes with and without representations of shape.

In this work it is described how to use the curvature function, the Fourier descriptors, and the coordinate functions of a contour to achieve automatic recognition of biological shapes. Those representations of shape and the coordinate functions were applied to recognize human corneal endothelial cells embedded in a sample of tissue. We assume that when the coordinates of the points of contours are analyzed directly, no representation of shape is being used. We applied scale-space filtering to the coordinate functions, to compensate the effects of scaling and to minimize the error due to quantization. A technique for compensating the effects of rotation, with or without the use of a representation of shape, is proposed. Our results show that, for a wide range of biological shapes, no representation of shape is required to solve or avoid the problems caused by translation, scaling, and rotation. We conclude that for certain applications the use of a representation of shape can provide some advantages. However, the coordinate functions of contours, evolved in scale-space, can be efficiently used, yielding even better results in applications of robotics and computer vision related to the recognition of biological shapes.

Cell Biology↗

PubMed2006

Modelling of sensory and instrumental texture parameters in processed cheese by near infrared reflectance spectroscopy.

This study investigated the application of near infrared (NIR) reflectance spectroscopy to the measurement of texture (sensory and instrumental) in experimental processed cheese samples. Spectra (750 to 2498 nm) of cheeses were recorded after 2 and 4 weeks storage at 4 degrees C. Trained assessors evaluated 9 sensory properties, a texture profile analyser (TPA) was used to record 5 instrumental parameters and cheese 'meltability' was measured by computer vision. Predictive models for sensory and instrumental texture parameters were developed using partial least squares regression on raw or pre-treated spectral data. Sensory attributes and instrumental texture measurements were modelled with sufficient accuracy to recommend the use of NIR reflectance spectroscopy for routine quality assessment of processed cheese.

Adult↗

PubMedDate not supplied

Behavioral monitoring of trained insects for chemical detection.

A portable, handheld volatile odor detector ("Wasp Hound") that utilizes a computer vision system and Microplitis croceipes (Cresson) (Hymenoptera: Braconidae), a parasitoid wasp, as the chemical sensor was created. Five wasps were placed in a test cartridge and placed inside the device. Wasps were either untrained or trained by associative learning to detect 3-octanone, a common fungal volatile chemical. The Wasp Hound sampled air from the headspace of corn samples prepared within the lab and, coupled with Visual Cortex, a software program developed using the LabView graphical programming language, monitored and analyzed wasp behavior. The Wasp Hound, with conditioned wasps, was able to detect 0.5 mg of 3-octanone within a 240 mL glass container filled with feed corn ( approximately 2.6 x 10(-5) mol/L). The Wasp Hound response to the control (corn alone) and a different chemical placed in the corn (0.5 mg of myrcene) was significantly different than the response to the 3-octanone. Wasp Hound results from untrained wasps were significantly different from trained wasps when comparing the responses to 3-octanone. The Wasp Hound may provide a unique method for monitoring grains, peanuts, and tree nuts for fungal growth associated with toxin production, as well as detecting chemicals associated with forensic investigations and plant/animal disease.

Animals↗

PubMed2000

Fast similarity search in three-dimensional structure databases

Given a database D of three-dimensional (3D) molecular structures and a target molecule Q, the similarity search problem is to find the molecules O in D that match Q after allowing for an arbitrary number of whole-structure rotations and translations as well as a certain number of edit operations. The edit operations include relabeling an atom, deleting an atom, and inserting an atom. This search operation arises in many biochemical applications. In this paper we study the similarity search problem and a class of related queries. We present a computer vision based technique, called geometric hashing, for processing these queries. Experimental results on a database of 3D molecular structures obtained from the National Cancer Institute indicate the good performance of the presented technique.

Journal Article↗