Analysis of 3D pathology samples using weakly supervised AI.

Human tissue, which is inherently three-dimensional (3D), is traditionally examined through standard-of-care histopathology as limited two-dimensional (2D) cross-sections that can insufficiently represent the tissue due to sampling bias. To holistically characterize histomorphology, 3D imaging modalities have been developed, but clinical translation is hampered by complex manual evaluation and lack of computational platforms to distill clinical insights from large, high-resolution datasets. We present TriPath, a deep-learning platform for processing tissue volumes and efficiently predicting clinical outcomes based on 3D morphological features. Recurrence risk-stratification models were trained on prostate cancer specimens imaged with open-top light-sheet microscopy or microcomputed tomography. By comprehensively capturing 3D morphologies, 3D volume-based prognostication achieves superior performance to traditional 2D slice-based approaches, including clinical/histopathological baselines from six certified genitourinary pathologists. Incorporating greater tissue volume improves prognostic performance and mitigates risk prediction variability from sampling bias, further emphasizing the value of capturing larger extents of heterogeneous morphology.

A multimodal generative AI copilot for human pathology.

Computational pathology1,2 has witnessed considerable progress in the development of both task-specific predictive models and task-agnostic self-supervised vision encoders3,4. However, despite the explosive growth of generative artificial intelligence (AI), there have been few studies on building general-purpose multimodal AI assistants and copilots5 tailored to pathology. Here we present PathChat, a vision-language generalist AI assistant for human pathology. We built PathChat by adapting a foundational vision encoder for pathology, combining it with a pretrained large language model and fine-tuning the whole system on over 456,000 diverse visual-language instructions consisting of 999,202 question and answer turns. We compare PathChat with several multimodal vision-language AI assistants and GPT-4V, which powers the commercially available multimodal general-purpose AI assistant ChatGPT-4 (ref. 6). PathChat achieved state-of-the-art performance on multiple-choice diagnostic questions from cases with diverse tissue origins and disease models. Furthermore, using open-ended questions and human expert evaluation, we found that overall PathChat produced more accurate and pathologist-preferable responses to diverse queries related to pathology. As an interactive vision-language AI copilot that can flexibly handle both visual and natural language inputs, PathChat may potentially find impactful applications in pathology education, research and human-in-the-loop clinical decision-making.

AI-based pathology predicts origins for cancers of unknown primary.

Cancer of unknown primary (CUP) origin is an enigmatic group of diagnoses in which the primary anatomical site of tumour origin cannot be determined1,2. This poses a considerable challenge, as modern therapeutics are predominantly specific to the primary tumour3. Recent research has focused on using genomics and transcriptomics to identify the origin of a tumour4-9. However, genomic testing is not always performed and lacks clinical penetration in low-resource settings. Here, to overcome these challenges, we present a deep-learning-based algorithm-Tumour Origin Assessment via Deep Learning (TOAD)-that can provide a differential diagnosis for the origin of the primary tumour using routinely acquired histology slides. We used whole-slide images of tumours with known primary origins to train a model that simultaneously identifies the tumour as primary or metastatic and predicts its site of origin. On our held-out test set of tumours with known primary origins, the model achieved a top-1 accuracy of 0.83 and a top-3 accuracy of 0.96, whereas on our external test set it achieved top-1 and top-3 accuracies of 0.80 and 0.93, respectively. We further curated a dataset of 317 cases of CUP for which a differential diagnosis was assigned. Our model predictions resulted in concordance for 61% of cases and a top-3 agreement of 82%. TOAD can be used as an assistive tool to assign a differential diagnosis to complicated cases of metastatic tumours and CUPs and could be used in conjunction with or in lieu of ancillary tests and extensive diagnostic work-ups to reduce the occurrence of CUP.

cAMP/PKA signaling regulates TDP-43 aggregation and mislocalization.

Cytoplasmic mislocalization and aggregation of TDP-43 protein are hallmarks of amyotrophic lateral sclerosis (ALS) and are observed in the vast majority of both familial and sporadic cases. How these two interconnected processes are regulated on a molecular level, however, remains enigmatic. Genome-wide screens for modifiers of the ALS-associated genes TDP-43 and FUS have identified the phospholipase D (Pld) pathway as a key regulator of ALS-related phenotypes in the fruit fly Drosophila melanogaster [M. W. Kankel et al., Genetics 215, 747-766 (2020)]. Here, we report the results of our search for downstream targets of the enzymatic product of Pld, phosphatidic acid. We identify two conserved negative regulators of the cAMP/PKA signaling pathway, the phosphodiesterase dunce and the inhibitory subunit PKA-R2, as modifiers of pathogenic phenotypes resulting from overexpression of the Drosophila TDP-43 ortholog TBPH. We show that knockdown of either of these genes results in a mitigation of both TBPH aggregation and mislocalization in larval motor neuron cell bodies, as well as an amelioration of adult-onset motor defects and shortened lifespan induced by TBPH. We determine that PKA kinase activity is downstream of both TBPH and Pld and that overexpression of the PKA target CrebA can rescue TBPH mislocalization. These findings suggest a model whereby increasing cAMP/PKA signaling can ameliorate the molecular and functional effects of pathological TDP-43.

Artificial Intelligence-Triaged 3-Dimensional Pathology to Improve Detection of Esophageal Neoplasia While Reducing Pathologist Workloads.

Early detection of esophageal neoplasia via evaluation of endoscopic surveillance biopsies is the key to maximizing survival for patients with Barrett's esophagus, but it is hampered by the sampling limitations of conventional slide-based histopathology. Comprehensive evaluation of whole biopsies with 3-dimensional (3D) pathology may improve early detection of malignancies, but large 3D pathology data sets are tedious for pathologists to analyze. Here, we present a deep learning-based method to automatically identify the most critical 2-dimensional (2D) image sections within 3D pathology data sets for pathologists to review. Our method first generates a 3D heatmap of neoplastic risk for each biopsy, then classifies all 2D image sections within the 3D data set in order of neoplastic risk. In a clinical validation study, we diagnose esophageal biopsies with artificial intelligence-triaged 3D pathology (3 images per biopsy) vs standard slide-based histopathology (16 images per biopsy) and show that our method improves detection sensitivity while reducing pathologist workloads.

Optimized flip angle schemes for the split acquisition of fast spin-echo signals (SPLICE) sequence and application to diffusion-weighted imaging.

PURPOSE: The diffusion-weighted SPLICE (split acquisition of fast spin-echo signals) sequence employs split-echo rapid acquisition with relaxation enhancement (RARE) readout to provide images almost free of geometric distortions. However, due to the varying T 2 $$ {}_2 $$ -weighting during k-space traversal, SPLICE suffers from blurring. This work extends a method for controlling the spatial point spread function (PSF) while optimizing the signal-to-noise ratio (SNR) achieved by adjusting the flip angles in the refocusing pulse train of SPLICE. METHODS: An algorithm based on extended phase graph (EPG) simulations optimizes the flip angles by maximizing SNR for a flexibly chosen predefined target PSF that describes the desired k-space density weighting and spatial resolution. An optimized flip angle scheme and a corresponding post-processing correction filter which together achieve the target PSF was tested by healthy subject brain imaging using a clinical 1.5 T scanner. RESULTS: Brain images showed a clear and consistent improvement over those obtained with a standard constant flip angle scheme. SNR was increased and apparent diffusion coefficient estimates were more accurate. For a modified Hann k-space weighting example, considerable benefits resulted from acquisition weighting by flip angle control. CONCLUSION: The presented flexible method for optimizing SPLICE flip angle schemes offers improved MR image quality of geometrically accurate diffusion-weighted images that makes the sequence a strong candidate for radiotherapy planning or stereotactic surgery.

Effect of melatonin cream on acute radiation dermatitis in patients with primary breast cancer: A double-blind, randomized, placebo-controlled trial.

AIM: This was a double-blind, placebo-controlled randomized study investigating whether melatonin can protect against radiation dermatitis in women receiving radiation therapy for primary breast cancer. METHODS: Patients were included before radiation therapy and followed once weekly throughout treatment with a 3-week follow-up. Patients applied 1 g of cream to the irradiated skin twice daily, consisting of either 25 mg/g melatonin and 150 mg/g dimethyl sulfoxide, or placebo. Our outcomes were the Radiation Therapy Oncology Group's (RTOG) acute radiation morbidity scoring criteria for skin, a pixel analysis of erythema in clinical photographs, and patients' use of corticosteroid cream. Outcomes were evaluated once weekly throughout the trial. The primary outcomes were RTOG-score and pixel analysis at 2 weeks follow-up. Secondary outcomes were the use of corticosteroid cream and analyses of RTOG-scores and pixel analyses throughout the trial. RESULTS: Sixty-five patients were included, 17 dropped out, totaling 26 and 22 patients randomized to melatonin and placebo, respectively. RTOG-scores and pixel analyses at 2 weeks follow-up showed no difference p = .441 and p = .890, respectively). There was no difference in the use of corticosteroid cream (p = .055). Using logistic regression, the melatonin group had a higher likelihood of having a low RTOG-score (p = .0016). The logistic regression showed no difference between the groups for the pixel analyses. CONCLUSION: Our primary outcome showed no difference in RTOG-scores at 2 weeks follow-up, however, the RTOG-score over the entire duration of the study demonstrated a protective effect of melatonin. Further studies are warranted investigating higher doses of melatonin, and whether corticosteroids may influence the effect of melatonin cream against radiation dermatitis.

Quality-of-life outcomes following topical melatonin application against acute radiation dermatitis in patients with early breast cancer: A double-blind, randomized, placebo-controlled trial.

The aim of this double-blind, placebo-controlled, randomized study was to investigate whether topical melatonin administered during radiation therapy could increase the quality of life in patients with primary breast cancer. Patients were followed from the first radiation fraction until 3 weeks after the last. The patients applied 1 g of cream to the irradiated area of the skin twice daily, consisting of either 25 mg/g melatonin and 150 mg/g dimethyl sulfoxide, or a placebo cream. Outcomes were the European Organisation for Research and Treatment of Cancer's quality-of-life questionnaires for breast cancer (QLQ-C30 and QLQ-BR23) on the last day of radiation therapy. As a secondary outcome, we evaluated the breast symptom (BS) scores over the entire duration of the trial in a repeated measures linear model. We included 65 patients and had 17 drop-outs, thus totaling 26 and 22 patients in the melatonin and placebo groups, respectively. BS scores on the last day of radiation did not differ between groups (p = .333). However, the linear model analyzing BS for the entire duration showed that melatonin significantly decreased the symptoms (p = .001). There was no difference in the BS score on the last day of radiation, however, we found that the patients in the melatonin group had significantly lower BS scores over the entire duration of the trial.

Geometric distortions in clinical MRI sequences for radiotherapy: insights gained from a multicenter investigation.

BACKGROUND: As magnetic resonance imaging (MRI) becomes increasingly integrated into radiotherapy (RT) for enhanced treatment planning and adaptation, the inherent geometric distortion in acquired MR images pose a potential challenge to treatment accuracy. This study aimed to evaluate the geometric distortion levels in the clinical MRI protocols used across Danish RT centers and discuss influence of specific sequence parameters. Based on the variety in geometric performance across centers, we assess if harmonization of MRI sequences is a relevant measure. MATERIALS AND METHODS: Nine centers participated with 12 MRI scanners and MRI-Linacs (MRL). Using a travelling phantom approach, a reference MRI sequence was used to assess variation in baseline distortion level between scanners. The phantom was also scanned with local clinical MRI sequences for brain, head/neck (H/N), abdomen, and pelvis. The influence of echo time, receiver bandwidth, image weighting, and 2D/3D acquisition was investigated. RESULTS: We found a large variation in geometric accuracy across 93 clinical sequences examined, exceeding the baseline variation found between MRI scanners (σ = 0.22 mm), except for abdominal sequences where the variation was lower. Brain and abdominal sequences showed lowest distortion levels ([0.22, 2.26] mm), and a large variation in performance was found for H/N and pelvic sequences ([0.19, 4.07] mm). Post hoc analyses revealed that distortion levels decreased with increasing bandwidth and a less clear increase in distortion levels with increasing echo time. 3D MRI sequences had lower distortion levels than 2D (median of 1.10 and 2.10 mm, respectively), and in DWI sequences, the echo-planar imaging read-out resulted in highest distortion levels. CONCLUSION: There is a large variation in the geometric distortion levels of clinical MRI sequences across Danish RT centers, and between anatomical sites. The large variation observed makes harmonization of MRI sequences across institutions and adoption of practices from well-performing anatomical sites, a relevant measure within RT.

AI in Pathology: What could possibly go wrong?

The field of medicine is undergoing rapid digital transformation. Pathologists are now striving to digitize their data, workflows, and interpretations, assisted by the enabling development of whole-slide imaging. Going digital means that the analog process of human diagnosis can be augmented or even replaced by rapidly evolving AI approaches, which are just now entering into clinical practice. But with such progress comes challenges that reflect a variety of stressors, including the impact of unrepresentative training data with accompanying implicit bias, data privacy concerns, and fragility of algorithm performance. Beyond such core digital aspects, considerations arise related to difficulties presented by changing disease presentations, diagnostic approaches, and therapeutic options. While some tools such as data federation can help with broadening data diversity while preserving expertise and local control, they may not be the full answer to some of these issues. The impact of AI in pathology on the field's human practitioners is still very much unknown: installation of unconscious bias and deference to AI guidance need to be understood and addressed. If AI is widely adopted, it may remove many inefficiencies in daily practice and compensate for staff shortages. It may also cause practitioner deskilling, dethrilling, and burnout. We discuss the technological, clinical, legal, and sociological factors that will influence the adoption of AI in pathology, and its eventual impact for good or ill.

Teachers' teleworking job satisfaction during the COVID-19 pandemic in Europe.

This research takes insights from the job demand resource model to examine the teleworking job satisfaction of teachers for the period of COVID-19 pandemic. This study evidenced that teachers' satisfaction with teleworking has been reduced as a consequence of the job demand increase. In contrast, access to adequate resources has allowed them to confront the challenges of teleworking, thus increasing their job satisfaction. The adverse effect of job demands on teleworking job satisfaction is buffered by job resources as teachers' required extra means to confront unexpected and increased job demands. The technological gap between younger and older teachers was uncovered.

Proceedings of the fifth international Molecular Pathological Epidemiology (MPE) meeting.

Cancer heterogeneities hold the key to a deeper understanding of cancer etiology and progression and the discovery of more precise cancer therapy. Modern pathological and molecular technologies offer a powerful set of tools to profile tumor heterogeneities at multiple levels in large patient populations, from DNA to RNA, protein and epigenetics, and from tumor tissues to tumor microenvironment and liquid biopsy. When coupled with well-validated epidemiologic methodology and well-characterized epidemiologic resources, the rich tumor pathological and molecular tumor information provide new research opportunities at an unprecedented breadth and depth. This is the research space where Molecular Pathological Epidemiology (MPE) emerged over a decade ago and has been thriving since then. As a truly multidisciplinary field, MPE embraces collaborations from diverse fields including epidemiology, pathology, immunology, genetics, biostatistics, bioinformatics, and data science. Since first convened in 2013, the International MPE Meeting series has grown into a dynamic and dedicated platform for experts from these disciplines to communicate novel findings, discuss new research opportunities and challenges, build professional networks, and educate the next-generation scientists. Herein, we share the proceedings of the Fifth International MPE meeting, held virtually online, on May 24 and 25, 2021. The meeting consisted of 21 presentations organized into the three main themes, which were recent integrative MPE studies, novel cancer profiling technologies, and new statistical and data science approaches. Looking forward to the near future, the meeting attendees anticipated continuous expansion and fruition of MPE research in many research fronts, particularly immune-epidemiology, mutational signatures, liquid biopsy, and health disparities.

Development of a vendor neutral MRI distortion quality assurance workflow.

With the utilization of magnetic resonance (MR) imaging in radiotherapy increasing, routine quality assurance (QA) of these systems is necessary. The assessment of geometric distortion in images used for radiotherapy treatment planning needs to be quantified and monitored over time. This work presents an adaptable methodology for performing routine QA for systematic MRI geometric distortion. A software tool and compatible protocol (designed to work with any CT and MR compatible phantom on any scanner) were developed to quantify geometric distortion via deformable image registration. The MR image is deformed to the CT, generating a deformation field, which is sampled, quantifying geometric distortion as a function of distance from scanner isocenter. Configurability of the QA tool was tested, and results compared to those provided from commercial solutions. Registration accuracy was investigated by repeating the deformable registration step on the initial deformed MR image to define regions with residual distortions. The geometric distortion of four clinical systems was quantified using the customisable QA method presented. Maximum measured distortions varied from 2.2 to 19.4 mm (image parameter and sampling volume dependent). The workflow was successfully customized for different phantom configurations and volunteer imaging studies. Comparison to a vendor supplied solution showed good agreement in regions where the two procedures were sampling the same imaging volume. On a large field of view phantom across various scanners, the QA tool accurately quantified geometric distortions within 17-22 cm from scanner isocenter. Beyond these regions, the geometric integrity of images in clinical applications should be considered with a higher degree of uncertainty due to increased gradient nonlinearity and B0 inhomogeneity. This tool has been successfully integrated into routine QA of the MRI scanner utilized for radiotherapy within our department. It enables any low susceptibility MR-CT compatible phantom to quantify the geometric distortion on any MRI scanner with a configurable, user friendly interface for ease of use and consistency in data collection and analysis.

Accuracy of automatic structure propagation for daily magnetic resonance image-guided head and neck radiotherapy.

BACKGROUND AND PURPOSE: Deformable image registration (DIR) and contour propagation are used in daily online adaptation for hybrid MRI linac (MRL) treatments. The accuracy of the propagated contours may vary depending on the chosen workflow (WF), affecting the amount of required manual corrections. This study investigated the impact of three different WFs of contour propagations produced by a clinical treatment planning system for a high-field MRL on head and neck cancer patients. METHODS: Seventeen patients referred for curative radiotherapy for oropharyngeal cancer underwent standard CT-based dose planning and MR scans in the treatment position for planning (pMR), and at the 10th (MR10), 20th (MR20) and 30th (MR30) fraction (±2). The primary tumour, a metastatic lymph node and 8 organs at risk were manually delineated on each set of T2 weighted images. Delineations were repeated one month later on the pMR by the same observer to determine the intra-observer variation (IOV). Three WFs were used to deform images in the treatment planning system for the high-field MRL: In WF1, only the planning image and contours were used as a reference for DIR and propagation to MR10,20,30. The most recently acquired image set prior to the daily images was deformed and uncorrected (WF2) versus manually corrected (WF3) structures propagated to the session image. Dice similarity coefficient (DSC), mean surface distance (MSD) and Hausdorff distance (HD) were calculated for each structure in each model. RESULTS: Population median DSC, MSD and HD for WF1 and WF3 were similar and slightly better than for WF2. WF3 provided higher accuracy than WF1 for structures that are likely to shrink. All DIR workflows were less accurate than the IOV. CONCLUSIONS: WF1 and WF3 provide higher accuracy in structure propagation than WF2. Manual revision and correction of propagated structures are required for all evaluated workflows.

Ibuprofen-loaded centrifugally spun microfibers for quick relief of inflammation in rats.

The conventional dosage forms (tablets, capsules) of ibuprofen have less potential in the suppression of pain and inflammation due to their slow dissolution rates and lower bioavailability. The aim of this study was to fabricate fibrous solid dispersion of ibuprofen for improved dissolution rate and quick therapeutic action. Drug-loaded microfibers were fabricated using centrifugal melt spinning (CMS) technique from the physical mixture of sucrose, ibuprofen and a hydrophilic polymer, PVP. These fibers were characterized by SEM, PXRD, DSC, and FTIR spectroscopy. The selected formulation was also pressed into tablets by direct compression method followed by its in vitro and in vivo characterization. The production yield of fibers was 75 ± 2% with an average diameter of 15 ± 5 µm. The drug loading efficiency (DLE) was 85 ± 5%. The tablets dissolved rapidly (<40 s). In vitro dissolution studies have shown >85% of ibuprofen dissolved from tablet within first 2 min which was ∼5 times quicker than drug alone. Dissolution efficiency has improved from 0.63 of ibuprofen to 0.95 of that in fibers with ∼7 times reduction in mean dissolution time. PXRD, and DSC have shown the amorphous state of ibuprofen in the formulation and FTIR spectra demonstrated no interaction of drug with excipients. In vivo anti-inflammatory studies using rabbits revealed a significant (p < 0.05) reduction in paw volume (mm) in the groups treated with fibrous formulation. This study concludes that microfibers produced by centrifugal melt spinning have improved dissolution rates and bioavailability of ibuprofen. Incorporation of polymer in the formulations improves the production yield and drug loading efficiency of microfibers.

Heterologous expression of azoreductase-encoding gene azrS of Bacillus sp. MR-1/2 for enhanced azo dye decolorization and wastewater treatment.

In Pakistan, 55% of textile exports are contributed by textile-units of Faisalabad. The effluents of these textile units, being discharged without any treatment, contain the contamination of a huge amount of synthetic azo dyes. The objective of the current research was to evaluate the contribution of an azoreductase-encoding gene (azrS) from a pre-characterized azo dye decolorizing bacterial strain Bacillus sp. MR-1/2 in a high copy number host system (pUC19-T7-Top-T) of Escherichia coli strain DH5α followed by in-silico prediction of azoreductase enzyme (AzrS) function. The recombinant cells that contained azrS had a significantly higher rate of color removal in congo red and reactive black-5 dyes when compared to wild-type MR-1/2 and E. coli DH5α after 72 h of incubation. Moreover, we were able to show that the recombinant strain significantly reduced the values of all tested parameters (pH, EC, turbidity, TSS, and COD) in actual wastewater. In support of our results, it was also predicted through bioinformatics analysis that the deduced azoreductase protein of strain MR-1/2 is linked with the dye decolorization ability of the strain through NAD(P)H-ubiquinone: oxidoreductase activity. Furthermore, we also found that the deduced protein resembled closely related proteins of protein databank in many features, yet some unique features were predicted in the enzyme activity of strain MR-1/2. It was concluded that the recombinant strain could be examined in pilot-scale experiments for textile wastewater treatment.

First clinical experiences with a high field 1.5 T MR linac.

Purpose: A 1.5 T MR Linac (MRL) has recently become available. MRL treatment workflows (WF) include online plan adaptation based on daily MR images (MRI). This study reports initial clinical experiences after five months of use in terms of patient compliance, cases, WF timings, and dosimetric accuracy. Method and materials: Two different WF were used dependent on the clinical situation of the day; Adapt To Position WF (ATP) where the reference plan position is adjusted rigidly to match the position of the targets and the OARs, and Adapt To Shape WF (ATS), where a new plan is created to match the anatomy of the day, using deformable image registration. Both WFs included three 3D MRI scans for plan adaptation, verification before beam on, and validation during IMRT delivery. Patient compliance and WF timings were recorded. Accuracy in dose delivery was assessed using a cylindrical diode phantom. Results: Nineteen patients have completed their treatment receiving a total of 176 fractions. Cases vary from prostate treatments (60Gy/20F) to SBRT treatments of lymph nodes (45 Gy/3F) and castration by ovarian irradiation (15 Gy/3F). The median session time (patient in to patient out) for 127 ATPs was 26 (21-78) min, four fractions lasted more than 45 min due to additional plan adaptation. For the 49 ATSs a median time of 12 (1-24) min was used for contouring resulting in a total median session time of 42 (29-91) min. Three SBRT fractions lasted more than an hour. The time on the MRL couch was well tolerated by the patients. The median gamma pass rate (2 mm,2% global max) for the adapted plans was 99.2 (93.4-100)%, showing good agreement between planned and delivered dose. Conclusion: MRL treatments, including daily MRIs, plan adaptation, and accurate dose delivery, are possible within a clinically acceptable timeframe and well tolerated by the patients.

Surface guided radiotherapy (SGRT) improves breast cancer patient setup accuracy.

PURPOSE: The purpose of the study was to investigate if surface guided radiotherapy (SGRT) can decrease setup deviations for tangential and locoregional breast cancer patients compared to conventional laser-based setup (LBS). MATERIALS AND METHODS: Both tangential (63 patients) and locoregional (76 patients) breast cancer patients were enrolled in this study. For LBS, the patients were positioned by aligning skin markers to the room lasers. For the surface based setup (SBS), an optical surface scanning system was used for daily setup using both single and three camera systems. To compare the two setup methods, the patient position was evaluated using verification imaging (field images or orthogonal images). RESULTS: For both tangential and locoregional treatments, SBS decreased the setup deviation significantly compared to LBS (P < 0.01). For patients receiving tangential treatment, 95% of the treatment sessions were within the clinical tolerance of ≤ 4 mm in any direction (lateral, longitudinal or vertical) using SBS, compared to 84% for LBS. Corresponding values for patients receiving locoregional treatment were 70% and 54% for SBS and LBS, respectively. No significant difference was observed comparing the setup result using a single camera system or a three camera system. CONCLUSIONS: Conventional laser-based setup can with advantage be replaced by surface based setup. Daily SGRT improves patient setup without additional imaging dose to breast cancer patients regardless if a single or three camera system was used.

Inflammatory arthritis and Mycobacterium Tuberculosis infection: a diagnostic and management challenge for Knee arthroplasty in endemic areas.

Tuberculosis continues to be one of the most challenging health problems more prevalent in developing countries. Pakistan ranks 5th in tuberculosis prevalence among the high-burden countries. Prosthetic joint infection of the knee by acid fast bacilli is a rare and distressing complication, occurring in nearly 1% of primary joint arthroplasties requiring prolonged medical treatment and multiple surgeries. A recent publication extensively reviewed English literature from 1952 to 2016, and repor ted only 64 prosthetic joint infec tion with tuberculosis, of which 27 cases involved the knee. Tuberculosis is a global health problem adding to the challenges that arthroplasty surgeons face in our resource-constrained setting. Furthermore, it presents as other inflammatory arthritis with almost same laboratory and radiological findings. The current paper was planned to highlight the preoperative and postoperative challenges that the arthroplasty surgeon may have in diagnosis and management of this rare infection. We included studies from 1996 to date which reported knee tuberculosis prosthetic joint infection that were managed by medication alone or with surgical intervention in patients who had undergone arthroplasty.