Natural language processing analysis of the theories of people with multiple sclerosis about causes of their disease.

BACKGROUND: While potential risk factors for multiple sclerosis (MS) have been extensively researched, it remains unclear how persons with MS theorize about their MS. Such theories may affect mental health and treatment adherence. Using natural language processing techniques, we investigated large-scale text data about theories that persons with MS have about the causes of their disease. We examined the topics into which their theories could be grouped and the prevalence of each theory topic. METHODS: A total of 486 participants of the Swiss MS Registry longitudinal citizen science project provided text data on their theories about the etiology of MS. We used the transformer-based BERTopic Python library for topic modeling to identify underlying topics. We then conducted an in-depth characterization of the topics and assessed their prevalence. RESULTS: The topic modeling analysis identifies 19 distinct topics that participants theorize as causal for their MS. The topics most frequently cited are Mental Distress (31.5%), Stress (Exhaustion, Work) (29.8%), Heredity/Familial Aggregation (27.4%), and Diet, Obesity (16.0%). The 19 theory topics can be grouped into four high-level categories: physical health (mentioned by 56.2% of all participants), mental health (mentioned by 53.7%), risk factors established in the scientific literature (genetics, Epstein-Barr virus, smoking, vitamin D deficiency/low sunlight exposure; mentioned by 47.7%), and fate/coincidence (mentioned by 3.1%). Our study highlights the importance of mental health issues for theories participants have about the causes of their MS. CONCLUSIONS: Our findings emphasize the importance of communication between healthcare professionals and persons with MS about the pathogenesis of MS, the scientific evidence base and mental health.

Multiple sclerosis (MS) is a disease that affects the brain and spinal cord, causing a wide range of symptoms. Our study investigated what people living with the disease think causes MS. We analyzed the replies given by 486 people who were questioned about their MS to look for patterns in the responses. We identified 19 distinct themes, notably mental and work-related stress, genetics, and dietary factors, which we grouped into 4 categories: physical health, mental health, established scientific risk factors, and chance. We found that mental health problems were viewed as a key factor for MS. Our work highlights the need for healthcare professionals to have transparent conversations with people with MS about what is known about the disease course and potential causes. In addition, it highlights the importance of fully informing and supporting people with MS regarding their mental health.

Effectiveness, Safety and Patients' Satisfaction of Nabiximols (Sativex®) on Multiple Sclerosis Spasticity and Related Symptoms in a Swiss Multicenter Study.

Background: Cannabinoid oro-mucosal spray nabiximols is approved for patients with moderate to severe multiple sclerosis spasticity (MSS) resistant to other antispastic medications. Few real-world data are available on the effectiveness, safety and patients' satisfaction in MS patients treated with nabiximols as monotherapy. Methods: To investigate the effectiveness, tolerability and satisfaction of nabiximols in a real-life multicentric Swiss cohort as monotherapy or with stable doses of other antispastic medications, and explore clinical features which may predict treatment response. The following data were collected at treatment start (baseline) and 12 weeks thereafter: Modified Ashworth scale (MAS), scores at numerical rating scales ranging from 0 (absent) to 10 (considerable) for effect on spasticity (sNRS), pain (pNRS), gait (gNRS), urinary symptoms (uNRS), tolerability (tNRS) as assessed by the treating neurologist, and overall treatment satisfaction (TsNRS) and tolerability (tNRS) as assessed by the patient. Results: Ninety-five patients (44 relapsing remitting, 37 secondary progressive and 14 primary progressive MS; median age = 53 (IQR 45-62); female 70%; median EDSS 6 (IQR 4-6), concomitant antispastic treatments in 54% of patients) were included. From baseline to week 12, median MAS score decreased from 3.0 to 2.0 (p < 0.001). Median scores of the each NRS also significantly decreased (p < 0.001 for all comparisons). At week 12, the median TsNRS and tTS scores were 8/10 (IQR: 6-9) and 9/10 (IQR: 7-10), respectively, and 93.7% of patients continued to use nabiximols at the average dose of six sprays/day. No clinical factors, including use of nabiximols as add on vs. monotherapy, were associated with responder status. Conclusions: Our first Swiss, multicentric, observational, real-life study supports and enhances previous finding of nabiximols as monotherapy and as add-on therapy, being an effective, safe and well-tolerated treatment option for resistant MS spasticity and spasticity-related symptoms (pain, bladder dysfunction and gait).

Biological therapy for inflammatory bowel disease: cyclical rather than lifelong treatment?

Inflammatory bowel disease (IBD) treatment was revolutionised with the arrival of biological therapy two decades ago. There are now multiple biologics and increasingly novel small molecules licensed for the treatment of IBD. Treatment guidelines highlight the need for effective control of inflammation and early escalation to advanced therapies to avoid long-term complications. Consequently, a large proportion of patients with IBD receive advanced therapies for a long time. Despite their beneficial risk-benefit profile, these treatments are not without risk of side effects, are costly to healthcare providers and pose a burden to the patient. It is, therefore, paramount to examine in which circumstances a temporary cessation of therapy can be attempted without undue clinical risk. Some patients may benefit from cyclical rather than continuous treatment. This review examines the risk of relapse after discontinuation of advanced therapies, how to identify patients at the lowest risk of relapse and the chance of recapturing response when flaring after discontinuation.

Preoperative Assessment of Medication-Related Osteonecrosis of the Jaw Using [18F]fluoride Positron Emission Tomography (PET)/CT and [18F]fluorodeoxyglucose PET/MRI in Correlation with Histomorphometry and Micro-CT-A Prospective Comparative Study.

OBJECTIVES: The purpose of this study was to investigate the imaging characteristics of medication-related osteonecrosis of the jaw (MRONJ) using [18F]fluoride positron emission tomography/computed tomography (PET/CT) and [18F]fluorodeoxyglucose (FDG) PET/magnetic resonance imaging (MRI) for preoperative assessment and to correlate them with microarchitectural and histomorphometric data with respect to clinical findings. METHODS: Twelve patients (five female; mean age 75 ± 7.6 yr) with symptomatic MRONJ underwent both scans on the same day, and imaging findings were used to plan surgical interventions for seven patients. Bone tracer uptake was classified as high, medium, or low, and surgical samples were evaluated using Micro-CT and histomorphometric analysis. RESULTS: CT showed medullary sclerosis in all patients, and MRI revealed gadolinium enhancement in four patients. PET imaging revealed remarkably elevated [18F]fluoride uptake and moderately increased [18F]FDG uptake in MRONJ compared to healthy jawbones, with both differences being statistically significant. [18F]fluoride uptake was associated with necrosis, bacteria, and inflammatory tissue. Micro-CT data did not show significant differences, but histomorphometric analysis revealed higher osteocyte and lacunae densities in the high [18F]fluoride uptake group, and more necrotic bone in the medium [18F]fluoride uptake group. Bacteria were observed in all areas. CONCLUSIONS: In summary, [18F]fluoride PET accurately identified MRONJ extent, revealing functional changes in jawbone remodeling not visible on CT. [18F]FDG PET showed differences in bone and soft tissue, though less pronounced. This method aids in evaluating disease activity and guiding treatment planning, requiring further research for optimal surgical approaches based on tracer uptake.

How [18F]FDG-PET/CT Affects the Management of Patients with Differentiated Thyroid Carcinoma in Clinical Routines.

PURPOSE: To investigate the impact of [18F]FDG-PET/CT on the management of differentiated thyroid carcinoma (DTC) in routine clinical settings. MATERIAL AND METHODS: In total, 98 patients (55 females, age 56 ± 18 years) with histologically confirmed thyroid cancer, including all types of DTC and poorly differentiated thyroid cancer (PDTC, n = 7), underwent [18F]FDG-PET/CT for staging or recurrence diagnostics performed using a state-of-the art clinical scanner (Biograph mCT, Siemens Healthineers) with a standardized examination protocol. The impact of PET/CT on clinical decision making was prospectively evaluated using standardized questionnaires completed by the referring physicians before and after PET/CT. Patient outcome was analyzed for OS drawn from patient records. RESULTS: Referring physicians were unable to establish a treatment plan for 81% of patients with thyroid cancer in the absence of PET/CT. The use of PET/CT had a notable influence on patient management, leading to the development of a well-defined treatment plan for 92% of patients. Moreover, after PET/CT a change in pre-PET/CT-intended treatments occurred in 32% of cases, and further invasive diagnostic could be waived in 7% of cases. [18F]FDG-PET/CT revealed a tumor detection rate of 68% (local tumor: 19%, lymph node metastases: 40%, distant metastases: 42%). HTg levels, when stimulated via TSH, were considerably higher in patients with metastases detected on PET/CT, compared to those without metastatic findings (p = 0.02). OS was significantly worse in patients with PDTC (p = 0.002) compared to follicular thyroid cancer (FTC) and PTC or even in patients with distant metastases at first diagnosis (p = 0.03). CONCLUSIONS: This prospective registry study confirms that [18F]FDG-PET/CT used in a routine clinical setting has a very important impact on the management of patients with thyroid cancer by initiating treatments and reducing the uses of additional imaging and invasive tests.

How [18F]-FDG-PET/CT Affects Clinical Management of Patients with Germ Cell Tumors in the Real World.

OBJECTIVE: The aim of this study was to evaluate the impact of PET/CT on clinical management of patients with germ cell tumors (GCTs) conducted in a real-world setting, including avoidance of invasive procedures, additional diagnostic imaging, and changes in treatment. METHODS: Patients with GCTs were prospectively enrolled into a PET/CT registry study between May 2013 and April 2021. Intended patient management prior and after PET/CT was documented using standardized questionnaires. Changes in oncologic staging and clinical management after PET/CT were recorded, including planned treatment and planned additional diagnostics. RESULTS: Forty-three male patients with GCTs were included consecutively in this study. After PET/CT, oncologic staging changed in 22/43 patients (51%), with upstaging in seven cases (16%), downstaging in ten cases (23%), and cancer relapse in five cases (11%). The number of patients with intended curative treatment remained stable, while a considerable change in intended therapeutic intervention was noted after PET/CT, with an increase in planned chemotherapy from three to eleven patients and a decrease in planned surgical resection from eleven to two patients. In addition, PET/CT contributed to preventing patients from intended invasive procedures including biopsy and surgery in 8/43 (19%) cases and from additional diagnostic procedures in 25 (58%) cases. CONCLUSION: With the use of FDG-PET/CT as a tool to guide patient management in GCTs, we observed a notable impact on clinical staging and a consequent reduction in the need for additional invasive and diagnostic procedures. These findings are expected to be even more consequential in the future as treatment modalities improve and the life expectancy of GCT patients further increases. KEY POINTS: PET/CT considerably influences the clinical stage of GCT patients. PET/CT has remarkable influence on the choice of therapeutic interventions and reduces additional diagnostic procedures.

Whole-Body Magnetic Resonance Imaging (MRI) for Staging Melanoma Patients in Direct Comparison to Computed Tomography (CT): Results from a Prospective Positron Emission Tomography (PET)/CT and PET/MRI Study.

PURPOSE: The consideration of radiation exposure is becoming more important in metastatic melanoma due to improved prognoses. The aim of this prospective study was to investigate the diagnostic performance of whole-body (WB) magnetic resonance imaging (MRI) in comparison to computed tomography (CT) with 18F-FDG positron emission tomography (PET)/CT and 18F-PET/MRI together with a follow-up as the reference standard. METHODS: Between April 2014 and April 2018, a total of 57 patients (25 females, mean age of 64 ± 12 years) underwent WB-PET/CT and WB-PET/MRI on the same day. The CT and MRI scans were independently evaluated by two radiologists who were blinded to the patients' information. The reference standard was evaluated by two nuclear medicine specialists. The findings were categorized into different regions: lymph nodes/soft tissue (I), lungs (II), abdomen/pelvis (III), and bone (IV). A comparative analysis was conducted for all the documented findings. Inter-reader reliability was assessed using Bland-Altman procedures, and McNemar's test was utilized to determine the differences between the readers and the methods. RESULTS: Out of the 57 patients, 50 were diagnosed with metastases in two or more regions, with the majority being found in region I. The accuracies of CT and MRI did not show significant differences, except in region II where CT detected more metastases compared to MRI (0.90 vs. 0.68, p = 0.008). On the other hand, MRI had a higher detection rate in region IV compared to CT (0.89 vs. 0.61, p > 0.05). The level of agreement between the readers varied depending on the number of metastases and the specific region, with the highest agreement observed in region III and the lowest observed in region I. CONCLUSIONS: In patients with advanced melanoma, WB-MRI has the potential to serve as an alternative to CT with comparable diagnostic accuracy and confidence across most regions. The observed limited sensitivity for the detection of pulmonary lesions might be improved through dedicated lung imaging sequences.

Impact on direct and indirect costs of switching patients with inflammatory bowel disease from intravenous to subcutaneous infliximab (CT-P13).

BACKGROUND: We aim to compare the real-life direct and indirect costs of switching patients from intravenous to subcutaneous (SC) CT-P13, an infliximab biosimilar, in a tertiary UK Inflammatory Bowel Disease (IBD) centre. METHODS: All adult patients with IBD on standard dosing CT-P13 (5 mg/kg 8 weekly) were eligible to switch. Of 169 patients eligible to switch to SC CT-P13, 98 (58%) switched within 3 months and one moved out of area. RESULTS: Total annual intravenous cost for 168 patients was £689 507.04 (direct=£653 671.20, indirect=£35 835.84). After the switch, as-treated analysis demonstrated total annual cost for 168 patients (70 intravenous and 98 SC) was £674 922.83 (direct = £654 563, indirect = £20 359.83) resulting in £891.80 higher cost to healthcare providers. Intention to treat analysis showed a total annual cost of £665 961.01 (direct = £655 200, indirect = £10 761.01) resulting in £1528.80 higher cost to healthcare providers. However, in each scenario, the significant decrease in indirect costs resulted in lower total costs after switching to SC CT-P13. CONCLUSIONS: Our real-world analysis demonstrates switching from intravenous to SC CT-P13 is broadly cost neutral to healthcare providers. SC preparations have marginally higher direct costs, switching allows for efficient use of intravenous infusion units and reduces costs to patients.

Electronic Health Diary Campaigns to Complement Longitudinal Assessments in Persons With Multiple Sclerosis: Nested Observational Study.

BACKGROUND: Electronic health diaries hold promise in complementing standardized surveys in prospective health studies but are fraught with numerous methodological challenges. OBJECTIVE: The study aimed to investigate participant characteristics and other factors associated with response to an electronic health diary campaign in persons with multiple sclerosis, identify recurrent topics in free-text diary entries, and assess the added value of structured diary entries with regard to current symptoms and medication intake when compared with survey-collected information. METHODS: Data were collected by the Swiss Multiple Sclerosis Registry during a nested electronic health diary campaign and during a regular semiannual Swiss Multiple Sclerosis Registry follow-up survey serving as comparator. The characteristics of campaign participants were descriptively compared with those of nonparticipants. Diary content was analyzed using the Linguistic Inquiry and Word Count 2015 software (Pennebaker Conglomerates, Inc) and descriptive keyword analyses. The similarities between structured diary data and follow-up survey data on health-related quality of life, symptoms, and medication intake were examined using the Jaccard index. RESULTS: Campaign participants (n=134; diary entries: n=815) were more often women, were not working full time, did not have a higher education degree, had a more advanced gait impairment, and were on average 5 years older (median age 52.5, IQR 43.25-59.75 years) than eligible nonparticipants (median age 47, IQR 38-55 years; n=524). Diary free-text entries (n=632; participants: n=100) most often contained references to the following standard Linguistic Inquiry and Word Count word categories: negative emotion (193/632, 30.5%), body parts or body functioning (191/632, 30.2%), health (94/632, 14.9%), or work (67/632, 10.6%). Analogously, the most frequently mentioned keywords (diary entries: n=526; participants: n=93) were "good," "day," and "work." Similarities between diary data and follow-up survey data, collected 14 months apart (median), were high for health-related quality of life and stable for slow-changing symptoms such as fatigue or gait disorder. Similarities were also comparatively high for drugs requiring a regular application, including interferon beta-1a (Avonex) and glatiramer acetate (Copaxone), and for modern oral therapies such as fingolimod (Gilenya) and teriflunomide (Aubagio). CONCLUSIONS: Diary campaign participation seemed dependent on time availability and symptom burden and was enhanced by reminder emails. Electronic health diaries are a meaningful complement to regular structured surveys and can provide more detailed information regarding medication use and symptoms. However, they should ideally be embedded into promotional activities or tied to concrete research study tasks to enhance regular and long-term participation.

The Real-World Experiences of Persons With Multiple Sclerosis During the First COVID-19 Lockdown: Application of Natural Language Processing.

BACKGROUND: The increasing availability of "real-world" data in the form of written text holds promise for deepening our understanding of societal and health-related challenges. Textual data constitute a rich source of information, allowing the capture of lived experiences through a broad range of different sources of information (eg, content and emotional tone). Interviews are the "gold standard" for gaining qualitative insights into individual experiences and perspectives. However, conducting interviews on a large scale is not always feasible, and standardized quantitative assessment suitable for large-scale application may miss important information. Surveys that include open-text assessments can combine the advantages of both methods and are well suited for the application of natural language processing (NLP) methods. While innovations in NLP have made large-scale text analysis more accessible, the analysis of real-world textual data is still complex and requires several consecutive steps. OBJECTIVE: We developed and subsequently examined the utility and scientific value of an NLP pipeline for extracting real-world experiences from textual data to provide guidance for applied researchers. METHODS: We applied the NLP pipeline to large-scale textual data collected by the Swiss Multiple Sclerosis (MS) registry. Such textual data constitute an ideal use case for the study of real-world text data. Specifically, we examined 639 text reports on the experienced impact of the first COVID-19 lockdown from the perspectives of persons with MS. The pipeline has been implemented in Python and complemented by analyses of the "Linguistic Inquiry and Word Count" software. It consists of the following 5 interconnected analysis steps: (1) text preprocessing; (2) sentiment analysis; (3) descriptive text analysis; (4) unsupervised learning-topic modeling; and (5) results interpretation and validation. RESULTS: A topic modeling analysis identified the following 4 distinct groups based on the topics participants were mainly concerned with: "contacts/communication;" "social environment;" "work;" and "errands/daily routines." Notably, the sentiment analysis revealed that the "contacts/communication" group was characterized by a pronounced negative emotional tone underlying the text reports. This observed heterogeneity in emotional tonality underlying the reported experiences of the first COVID-19-related lockdown is likely to reflect differences in emotional burden, individual circumstances, and ways of coping with the pandemic, which is in line with previous research on this matter. CONCLUSIONS: This study illustrates the timely and efficient applicability of an NLP pipeline and thereby serves as a precedent for applied researchers. Our study thereby contributes to both the dissemination of NLP techniques in applied health sciences and the identification of previously unknown experiences and burdens of persons with MS during the pandemic, which may be relevant for future treatment.

[18F]Fluoride Positron-Emission Tomography (PET) and [18F]FDG PET for Assessment of Osteomyelitis of the Jaw in Comparison to Computed Tomography (CT) and Magnetic Resonance Imaging (MRI): A Prospective PET/CT and PET/MRI Pilot Study.

To investigate imaging features of osteomyelitis of the jaw (OMJ) using [18F]fluoride positron emission tomography (PET) and [18F]fluorodeoxyglucose (FDG)-PET compared with computed tomography (CT) and magnetic resonance imaging (MRI) to assess extent and disease activity. Six female patients (55.3 ± 10.0 years) were enrolled for assessment of symptomatic OMJ. 4/6 patients underwent [18F]FDG-PET/MRI and [18F]fluoride-PET/CT, one patient MRI and [18F]fluoride-PET/CT and another patient only [18F]FDG-PET/MRI. Image analysis was performed by two radiologists, an oral and maxillofacial surgeon, and a nuclear medicine specialist. The extent of affected jawbone was analyzed both qualitatively and quantitatively, including the PET tracer uptake, CT-Hounsfield-Units (HU) and MRI parameters in affected and healthy jawbone. All patients had trabecular sclerosis in the affected jawbone compared to healthy jawbone (560 ± 328 HU vs. 282 ± 211 HU; p > 0.05), while 3/6 patients had cortical erosions. Bone marrow edema and gadolinium enhancement were documented in 5/6 patients. In affected jawbone, [18F]fluoride-uptake was increased in all patients compared to healthy jawbone (SUVmean 15.4 ± 4.2 vs. 2.1 ± 0.6; p < 0.05), and [18F]FDG-uptake was moderately higher (SUVmean 1.9 ± 0.7 vs. 0.7 ± 0.2; p > 0.05). The extent of regions with increased metabolic activity was less than the extent of morphologic changes in all patients. Information on jawbone metabolism and inflammation is different from morphologic changes and therefore has the potential to provide a more accurate and objective assessment of the extent and activity of OMJ.

Value of CT-Textural Features and Volume-Based PET Parameters in Comparison to Serologic Markers for Response Prediction in Patients with Diffuse Large B-Cell Lymphoma Undergoing CD19-CAR-T Cell Therapy.

The goal of this study was to investigate the value of CT-textural features and volume-based PET parameters in comparison to serologic markers for response prediction in patients with diffuse large B-cell lymphoma (DLBCL) undergoing cluster of differentiation (CD19)-chimeric antigen receptor (CAR)-T cell therapy. We retrospectively analyzed the whole-body (WB)-metabolic tumor volume (MTV), the WB-total lesion glycolysis (TLG) and first order textural features derived from 18F-FDG-PET/CT, as well as serologic parameters (C-reactive protein [CRP] and lactate dehydrogenase [LDH], leucocytes) prior and after CAR-T cell therapy in 21 patients with DLBCL (57.7 ± 14.7 year; 7 female). Interleukin 6 (IL-6) and IL-2 receptor peaks were monitored after treatment onset and compared with patient outcome judged by follow-up 18F-FDG-PET/CT. In 12/21 patients (57%), complete remission (CR) was observed, whereas 9/21 patients (43%) showed partial remission (PR). At baseline, WB-MTV and WB-TLG were lower in patients achieving CR (35 ± 38 mL and 319 ± 362) compared to patients achieving PR (88 ± 110 mL and 1487 ± 2254; p < 0.05). The "entropy" proved lower (1.81 ± 0.09) and "uniformity" higher (0.33 ± 0.02) in patients with CR compared to PR (2.08 ± 0.22 and 0.28 ± 0.47; p < 0.05). Patients achieving CR had lower levels of CRP, LDH and leucocytes at baseline compared to patients achieving PR (p < 0.05). In the entire cohort, WB-MTV and WB-TLG decreased after therapy onset (p < 0.01) becoming not measurable in the CR-group. Leucocytes and CRP significantly dropped after therapy (p < 0.01). The IL-6 and IL-2R peaks after therapy were lower in patients with CR compared to PR (p > 0.05). In conclusion, volume-based PET parameters derived from PET/CT and CT-textural features have the potential to predict therapy response in patients with DLBCL undergoing CAR-T cell therapy.

CT in Patients With External Fixation for Complex Lower Extremity Fractures: Impact of Iterative Metal Artifact Reduction Techniques on Metal Artifact Burden and Subjective Quality.

BACKGROUND. Lower extremity external fixators have complex geometries that induce pronounced metal artifact on CT. Iterative metal artifact reduction (iMAR) algorithms help reduce such artifact, although no dedicated iMAR preset exists for external fixators. OBJECTIVE. The purpose of our study was to compare iMAR presets for CT examinations in terms of quantitative metal artifact burden and subjective image quality in patients with external fixators for complex lower extremity fractures. METHODS. This retrospective study included 72 CT examinations in 56 patients (20 women, 36 men; mean age, 56 ± 18 [SD] years) with lower extremity external fixators (regular, hybrid, or monotube). Examinations were reconstructed without iMAR (hereafter referred to as "noMAR") and with three iMAR presets (iMARspine, iMARhip, iMARextremity). A radiology resident quantified metal artifact burden using software. Two radiology residents independently assessed overall image quality and diagnostic confidence using 4-point scales (4 = excellent [highest quality or highest confidence]). Techniques were compared using Bonferroni-corrected post hoc tests. Interreader agreement was assessed by intraclass correlation coefficients (ICCs). A post hoc multinomial regression model was used for predicting overall image quality. RESULTS. Mean quantitative metal artifact burden was 100,816 ± 45,558 for noMAR, 88,889 ± 44,028 for iMARspine, 82,295 ± 41,983 for iMARhip, and 81,956 ± 41,890 for iMARextremity. Overall image quality yielded an ICC of 0.94 or greater. Using pooled reader data, median overall image quality score for the regular fixator was 2 (noMAR), 3 (iMARspine and iMARhip), and 4 (iMARextremity); for the hybrid fixator, 1 (noMAR), 2 (iMARspine), and 3 (iMARhip and iMARextremity); and for the monotube fixator, 2 (noMAR), 3 (iMARspine and iMARhip), and 4 (iMARextremity). Metal artifact burden was lower and overall image quality was higher (p < .05) for iMARhip and iMARextremity than noMAR and iMARspine for all fixators (aside from image quality of iMARhip and iMARextremity vs iMARspine for regular fixators) but were not different (all, p > .05) between iMARhip and iMARextremity. Median diagnostic confidence was 4 for all fixators and reconstructions. Independent predictors of overall quality relative to noMAR were iMARspine (odds ratio [OR] = 1.92-5.51), iMARhip (OR = 5.56-31.10), and iMARextremity (OR = 7.07-38.21). All iMAR presets introduced new reconstruction artifacts for all examinations for both readers. CONCLUSION. For the three fixator types, iMARhip and iMARextremity achieved greatest metal artifact burden reduction and highest subjective image quality, although both introduced new reconstruction artifacts. CLINICAL IMPACT. CT using the two identified iMAR presets may facilitate perioperative management of external fixators.

Value of 18F-PSMA-PET/MRI for Assessment of Recurring Ranula.

We report the case of a 6-year-old patient with suspected recurrence of a plunging ranula in clinical and ultrasonographic examination. Surgical resection of the left submandibular and sublingual glands had already been performed. Since persistent glandular tissue could not be excluded with certainty via MRI, we expanded diagnostics by performing a PET/MRI using a head and neck imaging protocol and the radiotracer 18F-PSMA-1007, which is physiologically expressed by salivary gland tissue. The 18F-PSMA-PET/MRI provided evidence of a cystically transformed, diminishing seroma in the left retro-/submandibular region. No 18F-PSMA expressing glandular tissue could be detected in the area of resection, excluding a relapse of a plunging ranula. As a consequence, we opted for a conservative treatment without further surgical intervention. We conclude that a simultaneous 18F-PSMA-PET/MRI is a comprehensive imaging modality, which can help to rule out persistent salivary tissue and recurring plunging ranula. It is a useful tool to facilitate the decision making of surgical interventions.

18F-Fluoride PET/CT Imaging of Medication-Related Osteonecrosis of the Jaw in Conservative Treatment-A Case Report.

Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect in antiresorptive treatment. Treatment of MRONJ is considered primarily conservative with oral mouth rinses and antibiotics but may demand surgery, depending on the complaints and general condition of the patient, the extent of the necrosis, and the overall prognosis with respect to the underlying disease. A 77 year old female patient with invasive ductal breast cancer and bone metastases was treated with intravenous bisphosphonate (BP) zoledronic acid. During therapy, she developed MRONJ in the mandible with severe pain. Clinical examination revealed confluent exposed bone of the lower left jaw and a fistula at the right molar region. The panoramic radiograph revealed a mandibular osseous involvement with diffuse radiopaque areas between radiolucent areas. For preoperative planning, 18F-fluoride positron emission tomography/computed tomography (PET/CT) of the jaw was performed, showing substantially increased 18F-fluoride uptake in regions 38 to 47 of the mandible with a focal gap in region 36 (area of clinically exposed bone). CT revealed medullary sclerosis and cortical thickening with confluent periosteal reaction and focal cortical erosion in the regions 37 to 42, whereas the regions 43 to 47 were only subtly sclerotic without cortical thickening. After systemic antibiotic therapy with sultamicillin following significant symptom and pain relief, 18F-fluoride PET/CT imaging was performed again after 5 months. No changes in either CT and PET were observed in regions 38 to 42, whereas the bony sclerosis was slightly increased in regions 43 to 47 with a slight reduction of 18F-fluoride uptake. 18F-fluoride PET/CT showed no significant changes assessing the extent of MRONJ prior and after systemic antibiotic therapy, providing no evidence that conservative treatment reduced the extent of the MRONJ-affected jawbone. The additional information of 18F-fluoride PET enables to identify the true extent of MRONJ which may be underestimated by CT imaging alone. Patients with MRONJ undergoing conservative treatment could benefit because additional imaging may be avoided as the pre-therapeutic 18F-fluoride PET/CT delivers all information needed for further treatment. Our findings support the recommendation of a surgical approach as long-term antibiotics cannot downsize the extent of MRONJ.