Diverse organic-mineral associations in Jezero crater, Mars.

The presence and distribution of preserved organic matter on the surface of Mars can provide key information about the Martian carbon cycle and the potential of the planet to host life throughout its history. Several types of organic molecules have been previously detected in Martian meteorites1 and at Gale crater, Mars2-4. Evaluating the diversity and detectability of organic matter elsewhere on Mars is important for understanding the extent and diversity of Martian surface processes and the potential availability of carbon sources1,5,6. Here we report the detection of Raman and fluorescence spectra consistent with several species of aromatic organic molecules in the Máaz and Séítah formations within the Crater Floor sequences of Jezero crater, Mars. We report specific fluorescence-mineral associations consistent with many classes of organic molecules occurring in different spatial patterns within these compositionally distinct formations, potentially indicating different fates of carbon across environments. Our findings suggest there may be a diversity of aromatic molecules prevalent on the Martian surface, and these materials persist despite exposure to surface conditions. These potential organic molecules are largely found within minerals linked to aqueous processes, indicating that these processes may have had a key role in organic synthesis, transport or preservation.

Arthrocentesis of suspected septic sternoclavicular arthritis: microbial yield and predictors of culture positivity.

OBJECTIVE: Evaluate the microbial yield and factors predicting culture positivity for image-guided arthrocentesis of suspected septic sternoclavicular (SC) arthritis. MATERIALS AND METHODS: An electronic health record search identified image-guided SC joint aspirations for suspected septic arthritis. Data was extracted by retrospective chart review including patient demographics, procedure characteristics, pre-procedure lab testing, joint culture results, final SC joint diagnoses and any effect of positive synovial cultures on subsequent antibiotic therapy. Factors associated with positive joint fluid cultures were assessed using a Chi-squared test for categorical predictors and logistic regression for continuous predictors. RESULTS: A total of 31 SC arthrocenteses met inclusion criteria with most (81%) performed using ultrasound guidance. Synovial fluid was successfully aspirated in 19/31 (61%) of cases, and in all other cases lavage fluid was successfully obtained. Synovial cultures were positive in 9/31 (29%) of cases. A final diagnosis of septic arthritis was assigned to 20/31 cases (65%) in which 9/20 (45%) had positive synovial cultures. There was no statistically significant association between synovial culture positivity and risk factors for septic arthritis, positive blood cultures, pre-aspiration antibiotics and whether synovial fluid or lavage fluid was cultured. Serum white blood cell count (WBC) and erythrocyte sedimentation rate (ESR) demonstrated statistically significant positive correlation with positive synovial cultures. CONCLUSION: Arthrocentesis is effective for microbial speciation in SC septic arthritis, and diagnostic yield may be increased with lavage when encountering a dry tap. Normal serum WBC and ESR values indicate an extremely low likelihood of positive synovial cultures.

Can MR neurography of the common peroneal nerve predict a residual motor deficit in patients with foot drop?

OBJECTIVE: To determine if MR neurography of the common peroneal nerve (CPN) predicts a residual motor deficit at 12-month clinical follow-up in patients presenting with foot drop. MATERIALS AND METHODS: A retrospective search for MR neurography cases evaluating the CPN at the knee was performed. Patients were included if they had electrodiagnostic testing (EDX) within 3 months of imaging, ankle and/or forefoot dorsiflexion weakness at presentation, and at least 12-month follow-up. Two radiologists individually evaluated nerve size (enlarged/normal), nerve signal (T2 hyperintense/normal), muscle signal (T2 hyperintense/normal), muscle bulk (normal/Goutallier 1/Goutallier > 1), and nerve and muscle enhancement. Discrepancies were resolved via consensus review. Multivariable logistical regression was used to evaluate for association between each imaging finding and a residual motor deficit at 12-month follow-up. RESULTS: Twenty-three 3 T MRIs in 22 patients (1 bilateral, mean age 52 years, 16 male) met inclusion criteria. Eighteen cases demonstrated common peroneal neuropathy on EDX, and median duration of symptoms was 5 months. Six cases demonstrated a residual motor deficit at 12-month follow-up. Fourteen cases underwent CPN decompression (1 bilateral) within 1 year of presentation. Three cases demonstrated Goutallier > 1 anterior compartment muscle bulk. Multivariable logistical regression did not show a statistically significant association between any of the imaging findings and a residual motor deficit at 12-month follow-up. CONCLUSION: MR neurography did not predict a residual motor deficit at 12-month follow-up in patients presenting with foot drop, though few patients demonstrated muscle atrophy in this study.

Intravenous contrast does not improve detection of nerve lesions or active muscle denervation changes in MR neurography of the common peroneal nerve.

OBJECTIVE: To evaluate the effect of intravenous (IV) contrast on sensitivity, specificity, and accuracy of magnetic resonance (MR) neurography of the knee with attention to the common peroneal nerve (CPN) in identifying nerve lesions and active muscle denervation changes. MATERIALS AND METHODS: A retrospective search for contrast-enhanced MR neurography cases evaluating the CPN at the knee was performed. Patients with electrodiagnostic testing (EDX) within 3 months of imaging were included and those with relevant prior surgery were excluded. Two radiologists independently reviewed non-contrast sequences and then 4 weeks later evaluated non-contrast and contrast sequences. McNemar's tests were performed to detect a difference between non-contrast only and combined non-contrast and contrast sequences in identifying nerve lesions and active muscle denervation changes using EDX as the reference standard. RESULTS: Forty-four exams in 42 patients (2 bilateral) were included. Twenty-eight cases had common peroneal neuropathy and 29, 21, and 9 cases had active denervation changes in the anterior, lateral, and posterior compartment/proximal muscles respectively on EDX. Sensitivity, specificity, and accuracy of non-contrast versus combined non-contrast and contrast sequences for common peroneal neuropathy were 50.0%, 56.2%, and 52.3% versus 50.0%, 56.2%, and 52.3% for reader 1 and 57.1%, 50.0%, and 54.5% versus 64.3%, 56.2%, and 61.4% for reader 2. Sensitivity, specificity, and accuracy of non-contrast and combined non-contrast and contrast sequences in identifying active denervation changes for anterior, lateral, and posterior compartment muscles were not significantly different. McNemar's tests were all negative. CONCLUSION: IV contrast does not improve the ability of MR neurography to detect CPN lesions or active muscle denervation changes.

Core curriculum online lecture series in musculoskeletal imaging: initial results.

OBJECTIVE: To augment the educational resources available to training programs and trainees in musculoskeletal (MSK) radiology by creating a comprehensive series of Web-based open-access core curriculum lectures. MATERIALS AND METHODS: Speakers with recognized content and lecturing expertise in MSK radiology were invited to create digitally recorded lecture presentations across a series of 42 core curriculum topics in MSK imaging. Resultant presentation recordings, organized under curriculum subject headings, were archived as open-access video file recordings for online viewing on a dedicated Web page (http://radiologycorelectures.org/msk/). Information regarding the online core curriculum lecture series was distributed to members of the International Skeletal Society, Society of Skeletal Radiology, Society of Chairs of Academic Radiology Departments, and the Association of Program Directors in Radiology. Web page and online lecture utilization data were collected using Google Analytics (Alphabet, Mountain View, CA, USA). RESULTS: Forty-two lectures, by 38 speakers, were recorded, edited and hosted online. Lectures spanned ACGME curriculum categories of musculoskeletal trauma, arthritis, metabolic diseases, marrow, infection, tumors, imaging of internal derangement of joints, congenital disorders, and orthopedic imaging. Online access to the core curriculum lectures was opened on March 4, 2018. As of January 20, 2019, the core curriculum lectures have had 77,573 page views from 34,977 sessions. CONCLUSIONS: To date, the MSK core curriculum lecture series lectures have been widely accessed and viewed. It is envisioned that the initial success of the project will serve to promote ongoing content renewal and expansion to the lecture materials over time.

Preoperative MRI Shoulder Findings Associated with Clinical Outcome 1 Year after Rotator Cuff Repair.

Background Investigation of the use of preoperative MRI for providing prognostic information regarding clinical outcome following rotator cuff repair has been limited. Purpose To determine whether patients with more severe rotator cuff tears of the shoulder at preoperative MRI have a greater degree of residual pain and disability after rotator cuff repair. Materials and Methods This retrospective study included a cohort of 141 patients who underwent surgical repair of a full-thickness rotator cuff tear at a single institution between April 16, 2012, and September 3, 2015. The mean patient age was 56.8 years, and there were 100 men (mean age, 56.1 years) and 41 women (mean age, 56.3 years). Patients completed the Disabilities of the Arm, Shoulder, and Hand (DASH) survey (lower score indicates less pain and disability) before and 1 year after surgery. One musculoskeletal radiologist blinded to the DASH scores measured the maximal anterior-posterior width and medial-lateral retraction of the rotator cuff tear on the preoperative MRI and assessed tendon degeneration and composite muscle atrophy and fatty infiltration using categorical grading scales (grade 0 indicates no tendon degeneration or muscle atrophy and fatty infiltration, and higher grades indicate incrementally more severe tendon degeneration or muscle atrophy and fatty infiltration). Generalized estimating equation models were used to determine the association between preoperative MRI findings and the postoperative DASH score. Results There was a significant positive association (P < .05) between the measured tear width (estimate, 2.05), measured tear retraction (estimate, 3.52), and tendon degeneration grade (estimate, 1.59) and the postoperative DASH score. There was no significant association (P = .49) between the composite muscle atrophy and fatty infiltration grade (estimate, 0.31) and the postoperative DASH score. Conclusion Patients with larger rotator cuff tears, more tendon retraction, and more severe tendon degeneration have worse clinical outcome scores 1 year after rotator cuff repair. © RSNA, 2019.

Microbial community composition and dolomite formation in the hypersaline microbial mats of the Khor Al-Adaid sabkhas, Qatar.

The Khor Al-Adaid sabkha in Qatar is among the rare extreme environments on Earth where it is possible to study the formation of dolomite-a carbonate mineral whose origin remains unclear and has been hypothetically linked to microbial activity. By combining geochemical measurements with microbiological analysis, we have investigated the microbial mats colonizing the intertidal areas of sabhka. The main aim of this study was to identify communities and conditions that are favorable for dolomite formation. We inspected and sampled two locations. The first site was colonized by microbial mats that graded vertically from photo-oxic to anoxic conditions and were dominated by cyanobacteria. The second site, with higher salinity, had mats with an uppermost photo-oxic layer dominated by filamentous anoxygenic photosynthetic bacteria (FAPB), which potentially act as a protective layer against salinity for cyanobacterial species within the deeper layers. Porewater in the uppermost layers of the both investigated microbial mats was supersaturated with respect to dolomite. Corresponding to the variation of the microbial community's vertical structure, a difference in crystallinity and morphology of dolomitic phases was observed: dumbbell-shaped proto-dolomite in the mats dominated by cyanobacteria and rhombohedral ordered-dolomite in the mat dominated by FAPB.

Imaging of Kingella kingae musculoskeletal infections in children: a series of 5 cases.

PURPOSE: Kingella kingae musculoskeletal infections continue to be under-diagnosed and there remains a paucity of literature on its imaging features. The purpose of this manuscript is to review the imaging, clinical, and laboratory findings of microbiology-proven K. kingae infections. MATERIALS AND METHODS: A retrospective review of musculoskeletal infections between January 1, 2013 and Dec 31, 2016 yielded 134 patients from whom 5 patients had confirmed K. kingae infections (3 boys and 2 girls, mean age of 16 months, range 9-38 months). Picture archiving and communication system and electronic medical records were reviewed. RESULTS: At presentation, none of the patients had a fever and not all patients had abnormal inflammatory markers. Three patients had septic arthritis (2 knee and 1 sternomanubrial joints), one had epiphyseal osteomyelitis, and one had lumbar spondylodiscitis. The case of epiphyseal osteomyelitis of the distal humerus also had elbow joint involvement. A combination of radiography (n = 4), ultrasound (n = 2), and magnetic resonance (MR) imaging (n = 5) were performed. Prominent synovial thickening was observed for both knee and elbow joints and extensive regional myositis for all except for the patient with sternomanubrial joint infection. The diagnosis of K. kingae infection resulted in a change in the antibiotic regimen in 80% of the patients. CONCLUSION: Disproportionate synovial thickening, prominent peri-articular myositis, and/or characteristic sites of involvement demonstrating imaging features of infection or inflammation in a young child with mild infectious symptoms and elevated inflammatory markers should invoke the possibility of an underlying K. kingae infection.

Imaging Evaluation of Nonacute Shoulder Pain.

OBJECTIVE: A variety of radiographic views have been described in the literature for the initial imaging of nonacute shoulder pain. Multiple articles have also discussed the best next imaging test if radiographs do not show the diagnosis, especially the use of unenhanced MRI, MR arthrography, CT arthrography, and ultrasound. The purpose of this article is to examine the evidence for the most helpful radiographic views and the best imaging test after radiographs for different clinical presentations of chronic shoulder pain. CONCLUSION: The recommended radiographic views and best next imaging test after the radiograph depends on the clinical diagnosis. Ultrasound is generally preferred over MRI for evaluating chronic rotator cuff pain, whereas MR arthrography, preferably with abducted and externally rotated images, is most accurate for imaging chronic symptoms from a suspected labral tear or instability.

Imaging update on the glenoid labrum: variants versus tears.

This article reviews the normal labral variants of the shoulder and describes imaging features, including secondary signs, to help discriminate tears from normal variants. The labral variants can be divided into two main groups. One group is composed of nonstandard appearances in the labral shape, signal intensity, or the site of affixation to the glenoid rim. The other group consists of classic labral variants, where the labrum is partially or completely unattached to the subjacent bone, or a segment of the labrum is absent.

Preoperative Ultrasound-Guided Localization of the Lateral Femoral Cutaneous Nerve: From Guide Wire to Novel Clip.

BACKGROUND AND OBJECTIVE: Lateral femoral cutaneous nerve (LFCN) decompression and transposition are surgical treatment options for meralgia paresthetica. Identifying the LFCN during surgery may be challenging, and preoperative localization is a valuable adjunct in this case. The objective of this study was to explore a new technique using preoperative ultrasound-guided clip localization (USCL) of the LFCN. METHODS: After Institutional Review Board approval, data were collected on patients who underwent both preoperative ultrasound-guided wire localization (USWL) and USCL over the past 13 years. Skin-to-nerve time was calculated prospectively. RESULTS: Fifty-six patients were identified, 51 had USWL and 5 had USCL; the skin-to-nerve median time was 7.5 and 6 minutes, respectively. Six wires were misplaced, and this was at the beginning of utilization of the USWL technique. There were no nerve injury, infection, or bleeding complications related to either wire or clip placement. CONCLUSION: USWL or USCL is safe and time-efficient in LFCN surgeries.

Unreimbursed Costs of Multidisciplinary Conferences to a Radiology Department: A Prospective Analysis at an Academic Medical Center.

PURPOSE: Multidisciplinary conferences (MDCs) are important for clinical care but are unreimbursed and can be time-consuming for radiologists to prepare for and present. The purpose of this single-center, prospective, survey-based study is to measure the per-conference time and total time radiologists devote to MDCs at a single academic medical center. Secondary objectives are to determine the source of radiologist preparation time, and calculate the per conference and overall radiology departmental costs of MDC participation. METHODS: A prospective survey was performed to capture all radiology preparation and presentation time for MDCs in a 3-month period, which was then annualized. Total cost was calculated on the basis of Association of Administrators in Academic Radiology survey data for nonchair academic radiologist compensation plus a 30% fringe-benefit rate. RESULTS: The survey response rate was 86.9%. A total of 3,358 hours were devoted annually to MDCs, which represents time equivalent to 1.9 full-time equivalents or $1,155,152 in unreimbursed radiology departmental costs. Per-MDC total preparation and presentation time was 2.7 hours, at an annual cost of $46,440 for each weekly MDC. Radiologists used a combination of personal time (49.7%), academic time (42%), and/or clinical time (35.4%) to prepare for MDCs. Radiologists devoted a mean of 47.9 hours (1.2 weeks) of time per annum to MDCs. CONCLUSIONS: Radiologist time devoted to MDCs at the survey institution was substantial, and preparation time was drawn disproportionately from personal and academic time, which may have negative implications for burnout, recruitment and retention, and academic productivity unless it is effectively mitigated.

Imaging algorithms for evaluating suspected rotator cuff disease: Society of Radiologists in Ultrasound consensus conference statement.

The Society of Radiologists in Ultrasound convened a panel of specialists from a variety of medical disciplines to reach a consensus about the recommended imaging evaluation of painful shoulders with clinically suspected rotator cuff disease. The panel met in Chicago, Ill, on October 18 and 19, 2011, and created this consensus statement regarding the roles of radiography, ultrasonography (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography. The consensus panel consisted of two co-moderators, a facilitator, a statistician and health care economist, and 10 physicians who have specialty expertise in shoulder pain evaluation and/or treatment. Of the 13 physicians on the panel, nine were radiologists who were chosen to represent a broad range of skill sets in diagnostic imaging, different practice types (private and academic), and different geographical regions of the United States. Five of the radiologists routinely performed musculoskeletal US as part of their practice and four did not. There was also one representative from each of the following clinical specialties: rheumatology, physical medicine and rehabilitation, orthopedic surgery, and nonoperative sports medicine. The goal of this conference was to construct several algorithms with which to guide the imaging evaluation of suspected rotator cuff disease in patients with a native rotator cuff, patients with a repaired rotator cuff, and patients who have undergone shoulder replacement. The panel hopes that these recommendations will lead to greater uniformity in rotator cuff imaging and more cost-effective care for patients suspected of having rotator cuff abnormality.

Non-femoroacetabular impingement.

Femoroacetabular impingement is one of the causes of hip pain leading to acetabular labral tears and cartilage damage that may lead to the development of early osteoarthritis. More recently other causes of impingement have been recognized that may be the culprit for the painful hip. These causes include ischiofemoral, anterior inferior iliac spine/subspine and iliopsoas impingement. Ischiofemoral impingement syndrome is related to narrowing between the ischial tuberosity and lesser trochanter with abnormalities of the quadratus femoris muscle producing hip pain. Anterior inferior iliac spine/subspine impingement syndrome is defined as hip pain produced by abnormal contact between the anterior inferior iliac spine and proximal femur. Iliopsoas impingement may produce hip pain that is related to a thickened or taut iliopsoas tendon at the level of the acetabular rim/anterior hip capsule. Radiographs, magnetic resonance imaging, ultrasound, or computed tomography may help to better elucidate the problem while excluding intra-articular pathology or femoroacetabular impingement. Keeping these causes of impingement in mind when evaluating the painful hip will aid in diagnosis.

Sublabral clefts and recesses in the anterior, inferior, and posterior glenoid labrum at MR arthrography.

PURPOSE: To determine the prevalence of a normal variant cleft/recess at the labral-chondral junction in the anterior, inferior, and posterior portions of the shoulder joint. MATERIALS AND METHODS: One hundred and three consecutive patients (106 shoulders) who had a direct MR arthrogram followed by arthroscopic surgery were enrolled in this IRB-approved study. Scans were carried out on a 1.5-T scanner with an eight-channel shoulder coil. The glenoid rim was divided into eight segments and the labrum in all but the superior and anterosuperior segments was evaluated by two radiologists for the presence of contrast between the labrum and articular cartilage. We measured the depth of any cleft/recess and correlated the MR findings with surgical results. Generalized estimating equation models were used to correlate patient age and gender with the presence and depth of a cleft/recess, and Cohen's kappa values were calculated for interobserver variability. RESULTS: For segments that were normal at surgery, a cleft/recess was present within a segment on MR arthrogram images in as few as 7 % of patients (within the posteroinferior segment by observer 1), and in up to 61 % of patients (within the posterosuperior segment by observer 1). 55-83 % of these were only 1 mm deep. A 2- to 3-mm recess was seen within 0-37 % of the labral segments, most commonly in the anterior, anteroinferior, and posterosuperior segments. Age and gender did not correlate with the presence of a cleft/recess, although there was an association between males and a 2- to 3-mm deep recess (p = 0.03). The interobserver variability for each segment ranged between 0.15 and 0.49, indicating slight to moderate agreement. CONCLUSION: One-mm labral-chondral clefts are not uncommon throughout the labrum. A 2- to 3-mm deep smooth, medially curved recess in the anterior, anteroinferior or posterosuperior labrum can rarely be seen, typically as a continuation of a superior recess or anterosuperior labral variant.

Labral injuries due to iliopsoas impingement: can they be diagnosed on MR arthrography?

OBJECTIVE: Iliopsoas impingement is a new arthroscopic diagnosis that refers to an anterior labral injury caused by the iliopsoas tendon. Currently, there are no preoperative criteria to establish the diagnosis of iliopsoas impingement. The goal of this study was to determine whether there are imaging criteria that would identify iliopsoas impingement on preoperative MR arthrography. MATERIALS AND METHODS: This study compared the preoperative MR arthrograms of 23 patients who had iliopsoas impingement diagnosed at hip arthroscopy with the arthrograms of 24 patients who did not have iliopsoas impingement found at hip arthroscopy. All of the arthroscopies were performed by a single orthopedic hip surgeon. In all cases of impingement, there was an isolated injury to the labrum at the 3-o'clock position. All were treated by arthroscopic iliopsoas tenotomy performed at the labral level. The MR examinations of the 47 patients were evaluated independently by two musculoskeletal radiologists who were blinded to the diagnosis. The following characteristics of the iliopsoas tendon at the level of the anterior labrum were evaluated: lateral dip, increased signal intensity (SI) between the iliopsoas tendon and labrum, irregularity of the deep margin of the iliopsoas tendon, edema within the iliopsoas tendon or capsule at the 3-o'clock position, presence of a labral tear at the 3-o'clock position, dimensions of the iliopsoas tendon, and location of iliopsoas tendon as it passed the labrum. Statistical analysis was performed using the Kruskal Wallis test, Fisher exact test, and Cohen kappa. Values for p less than 0.05 were considered significant. RESULTS: Nineteen women (mean age, 35 years) and four men (mean age, 36 years) had central iliopsoas impingement. Sixteen women (mean age, 38 years) and eight men (mean age, 35 years) did not have central iliopsoas impingement (p=0.318). For the impingement and nonimpingement groups, lateral dip of the iliopsoas tendon was seen in 15 of 23 (65%) and 17 of 24 (71%) for reader 1 and 18 of 23 (78%) and 11 of 24 (46%) for reader 2, respectively (p=0.76 and 0.036, respectively). There was no difference between the groups for increased SI between the iliopsoas tendon and labrum (p=0.38 and 0.82, respectively), irregular deep margin of the iliopsoas tendon (p=0.61 and 0.35, respectively), thickness of the iliopsoas tendon (p=0.33), or tendon or capsule edema (p=0.37 and 0.77, respectively). Reader 1 found 20 of 23 and reader 2 18 of 23 labral tears at the 3-o'clock position in the iliopsoas impingement group, with 13 of 24 and 10 of 24 in the non-iliopsoas impingement group respectively (p=0.024 and 0.017, respectively). The combined iliopsoas tendon width for both readers was 10.2 mm (range, 8.1-14.3 mm) in women and 11.9 mm (range, 11.1-13.4 mm) in men in the iliopsoas impingement group (p=0.0285), and 11.0 mm (range, 9.0-12.6 mm) for women and 11.8 mm (range, 8.7-15.1 mm) for men in the non-iliopsoas impingement group (p=0.159). The iliopsoas tendon most commonly crossed the labrum at the 3-o'clock position in both groups (p=0.83-0.17). CONCLUSION: An acetabular labral tear at the 3-o'clock position should suggest the diagnosis of iliopsoas impingement.

In Situ Identification of Paleoarchean Biosignatures Using Colocated Perseverance Rover Analyses: Perspectives for In Situ Mars Science and Sample Return.

The NASA Mars 2020 Perseverance rover is currently exploring Jezero crater, a Noachian-Hesperian locality that once hosted a delta-lake system with high habitability and biosignature preservation potential. Perseverance conducts detailed appraisals of rock targets using a synergistic payload capable of geological characterization from kilometer to micron scales. The highest-resolution textural and chemical information will be provided by correlated WATSON (imaging), SHERLOC (deep-UV Raman and fluorescence spectroscopy), and PIXL (X-ray lithochemistry) analyses, enabling the distributions of organic and mineral phases within rock targets to be comprehensively established. Herein, we analyze Paleoarchean microbial mats from the ∼3.42 Ga Buck Reef Chert (Barberton greenstone belt, South Africa)-considered astrobiological analogues for a putative ancient martian biosphere-following a WATSON-SHERLOC-PIXL protocol identical to that conducted by Perseverance on Mars during all sampling activities. Correlating deep-UV Raman and fluorescence spectroscopic mapping with X-ray elemental mapping, we show that the Perseverance payload has the capability to detect thermally and texturally mature organic materials of biogenic origin and can highlight organic-mineral interrelationships and elemental colocation at fine spatial scales. We also show that the Perseverance protocol obtains very similar results to high-performance laboratory imaging, Raman spectroscopy, and µXRF instruments. This is encouraging for the prospect of detecting microscale organic-bearing textural biosignatures on Mars using the correlative micro-analytical approach enabled by WATSON, SHERLOC, and PIXL; indeed, laminated, organic-bearing samples such as those studied herein are considered plausible analogues of biosignatures from a potential Noachian-Hesperian biosphere. Were similar materials discovered at Jezero crater, they would offer opportunities to reconstruct aspects of the early martian carbon cycle and search for potential fossilized traces of life in ancient paleoenvironments. Such samples should be prioritized for caching and eventual return to Earth.