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2022 ◽  
Vol 12 (2) ◽  
pp. 563
Author(s):  
Matin Torabinia ◽  
Alexandre Caprio ◽  
Tamatha B. Fenster ◽  
Bobak Mosadegh

Uterine fibroids represent the highest prevalence of benign tumors in women, with reports ranging from 4.5% to 68.6%, with a significant bias towards African American women. For uterine fibroids, a significant decision is determining whether fibroids can be successfully removed using minimally invasive (MI) techniques or their removal requires open surgery. Currently, the standard-of-care for intra-procedural visualization for myomectomies is ultrasound, which has low image quality and requires a specially trained assistant. Currently, the state-of-the-art is to obtain a pre-procedural MRI scan of the patient, which can be used for diagnosis and pre-procedural planning. Although proven incredibly useful pre-procedurally, MRI scans are not often used intra-procedurally due to the inconvenient visualization as 2D slices, which are seen on 2D monitors that do not intuitively convey the depth or orientation of the fibroids, as needed to effectively perform myomectomies. To address this limitation, herein, we present the use of a mixed reality headset (i.e., Microsoft HoloLens 2), as a tool for intra-procedural image-guidance during a mock myomectomy of an ex vivo animal uterus. In this work, we created a patient-specific holographic rendering by performing image segmentation of an MRI scan of a custom-made uterine fibroid animal model. A physician qualitatively assessed the usefulness of the renderings for fibroid localization, as compared to the same visualization on a 2D monitor. In conclusion, the use of mixed reality as an intra-procedural image guidance tool for myomectomies was perceived as a better visualization technique that could lead to improvements in MI approaches and make them accessible to patients from lower socioeconomic populations.


Author(s):  
Sarmad Aslam ◽  
Jeffrey Tsang ◽  
Ian Bickle ◽  
Ali Saiepour

Objective: Prostate cancer is the most common male cancer in the UK. In many hospitals, patients are now being referred for a multi parametric (mp) MRI scan of their prostate as part of an evaluation for the presence of prostate cancer, prior to an ultrasound guided biopsy. PI-RADS score of 3 are defined as “equivocal” for the presence of prostate cancer. Thus, a PIRADS three lesion does not confidently determine whether there is significant prostate disease or not. Our aim is to determine the correlation of PIRADS three prostatic lesions with histology proven, clinically significant cancer. Methods: We performed a retrospective review on a cohort of 143 consecutive patients. Each patient underwent a mp-MRI scan of their prostate given a PIRADS score. PIRADS three lesions were analysed further based on histology and categorised into malignant and non-malignant lesions. PSA results and prostatic volume of PIRADS three lesions were also analysed. Results: We identified forty five patients with PIRADS 3 lesions out of 143 patients. Thirty-two patients subsequently underwent trans-rectal/trans-perineal ultrasound guided biopsy. 43% of patients were found to have had a malignant prostatic adenocarcinoma on histology. The remaining 56% had non-malignant findings. Of those with malignant disease, there was a higher median PSA and lower mean prostatic volume. Conclusions: The study confirms that a score of PIRADS three does not accurately differentiate between malignant and non-malignant lesions. Further investigations such as ultrasound-guided prostate biopsy and PSA parameters are required to accurately ascertain the nature of a prostate lesion with PIRADS score 3. Advances in knowledge: An ultrasound-guided prostate biopsy in patients with PIRADS 3 remains of paramount importance when distinguishing malignant versus non-malignant lesions. Multicentre data of MRI findings with PIRADS three scores is required to yield a sample size large enough to carry out statistical analysis.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Chao Ran ◽  
Jian Sun ◽  
Yunhui Qu ◽  
Na Long

Abstract Background Cervical cancer shows great differences in depth of invasion, metastasis, and other biological behaviors. The location of the lesion is special, so it is usually difficult to determine the clinical stage. This study aimed to explore the clinical value of magnetic resonance imaging (MRI) and tumor serum markers for the preoperative diagnosis of cervical cancer lymph node metastasis and para-uterine invasion. Methods A total of 200 patients with cervical cancer admitted to our hospital from January 2019 to January 2020 were collected as the research subjects. Comparing the diagnosis results of preoperative MRI scan, serum tumor markers, and postoperative pathological examination using single factor comparison, we determined the MRI scan results, the comprehensive matching rate between serum tumor markers (squamous cell carcinoma antigen (SCCA), carbohydrate antigen 125 (CA125)) and postoperative pathological results, and the differences of sensitivity, specificity, and accuracy in the prediction of lymph node metastasis and para-uterine infiltration of cervical cancer. Results The levels of SCCA and CA125 in patients with para-uterine invasion and lymph node metastasis were higher than those of patients without invasion and metastasis. Among them, the level of SCCA was significantly different (P<0.05). The level of CA125 was not statistically significant (P>0.05), so MRI combined with serum SCCA was selected for combined diagnosis in the later period. The sensitivity, specificity, and accuracy of MRI diagnosis of cervical cancer and para-uterine infiltrating lymph node metastasis and metastasis were 55.2, 91.6, and 89.5% and 55.2, 91.6, and 89.5%, respectively. These data in MRI combined with serum SCCA were 76.3, 95.3, and 94.3% and 63.2, 96.0, and 95.1%, respectively. The accuracy of tumor markers combined with MRI in the diagnosis of cervical cancer lymph node metastasis and para-uterine invasion was higher than that of MRI. Conclusions MRI combined with serum SCCA can more accurately identify cervical cancer lymph node metastasis and para-uterine invasion compared with MRI alone. Tumor marker combined with MRI diagnosis is an important auxiliary method for cervical cancer treatment and can provide comprehensive and reliable clinical evidence for evaluation before cervical cancer surgery.


Cancers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 6019
Author(s):  
Bettina Beuthien-Baumann ◽  
Christos Sachpekidis ◽  
Regula Gnirs ◽  
Oliver Sedlaczek

Hybrid imaging with positron emission tomography (PET) in combination with computer tomography (CT) is a well-established diagnostic tool in oncological staging and restaging. The combination of PET with magnetic resonance imaging (MRI) as a clinical scanner was introduced approximately 10 years ago. Although MRI provides superb soft tissue contrast and functional information without the radiation exposure of CT, PET-MRI is not as widely introduced in oncologic imaging as PET-CT. One reason for this hesitancy lies in the relatively long acquisition times for a PET-MRI scan, if the full diagnostic potential of MRI is exploited. In this review, we discuss the possible advantages of combined imaging protocols of PET-CT and PET-MRI, within the context of staging and restaging of patients under immunotherapy, in order to achieve “multi-hybrid imaging” in one single patient visit.


2021 ◽  
Vol 22 (4) ◽  
Author(s):  
Maciej Paszynski

This paper presents an overview of formulations and algorithms dedicated to modeling the influence of electromagnetic waves on the human head. We start from the three-dimensional MRI scan of the human head. We approximate the MRI scan by the continuous approximation span over three-dimensional h adaptive mesh with quadratic polynomials. Next, we introduce time-harmonic Maxwell equations with a 1.8 GHz cell-phone antenna. We solve the problem of the propagation of electromagnetic waves on the human head. We compute the specific absorption rate used as the heat source for the Pennes bioheat equation. Finally, we introduce the Pennes bio-heat equation modeling the heat generated by the electromagnetic waves propagating through the skull, tissue, and air layers in the human head. We discuss the discretization and time-stepping algorithm for the Pennes equation’s solution over the human head. Namely, we focus on the Crank-Nicolson time integration scheme, to solve the bioheat transfer equations. We employ the hp finite elements with hierarchical shape functions and hp adaptive algorithm in three-dimensions. We propose an adaptive algorithm mixed with time-stepping iterations, where we simultaneously adapt the computational mesh, solve the Maxwell and Pennes equations, and we iterative with time steps. We employ the sparse Gaussian elimination algorithm with low-rank compression of the off-diagonal matrix blocks for the factorization of matrices. We conclude with the statement that 15 minutes of talk with a 1.8 GHz antenna of 1 Wat power results in increased brain tissue temperature up to 38.4 Celsius degree.


Author(s):  
Olga V. Bozhko ◽  
Tolibdzhon A. Akhadov ◽  
Ilya A. Melnikov ◽  
Dmitry M. Dmitrenko ◽  
Tatyana D. Kostikova ◽  
...  

The objective was to assess the capabilities of MRI and CT in visualizing free bone and cartilage fragments in the knee cavity after lateral dislocation of the patella. Materials and methods. CT and MRI were performed in 220 patients, including 127 girls and 93 boys aged 12 to 18 years (mean age 14.5 years), with acute lateral patellar dislocation. Results. Lateral dislocation of the patella in 25% of cases led to the appearance of osteochondral fragments. CT scan revealed and confirmed osteochondral fragments surgery in 55 people (100%), MRI scan - in 50 people (90%). The sites of the detachment of the osteochondral fragments were: a medial facet of the patella in 22 (38.8%), the outer edge of femur lateral condyle in 33 (58.2%), t patella and lateral condyle of the femur in 2 patients (3%). Free cartilage fragments not detected by CT were detected by MRI in 2 patients. Conclusion. Patellar dislocation is an injury that is likely to require surgery. The volume of osteochondral and soft tissue lesions can be established with the maximum degree of probability by MRI while detecting small osteochondral fragments is most reliable with CT. Combining these two observation methods provides the complete possible information about the extent of damage, which allows timely resolution of treatment tactics.


Author(s):  
Sisir Siddamsetti ◽  
Alexander Shinn ◽  
Sandeep Gautam

Background Magnetic Resonance imaging (MRI) in patients (pts) with MRI-conditional cardiovascular implantable electronic devices (CIED) remain a logistical issue for device programming during the scan. In current practice, a trained person needs to be present on-site to program CIED for MRI scan. This can cause delay in patient care, rescheduling of tests and increase healthcare costs. A novel remote programming (RP) strategy can be utilized to reprogram the CIED remotely. We sought to explore the feasibility and safety of RP of CIED’s in pts undergoing MRI scan. Methods We implemented the Medtronic CIED RP software at our institution after ensuring HIPAA compliance. The MRI technician started the session by contacting an off-site remote operator and placing a programmer wand from 2090 Medtronic programmer over CIED. The remote operator logged into a remote access software and provided a unique access code to the MRI technician. After entering the access code into the programmer, the remote operator was able to program the device as needed. We conducted a periodic audit of the first 209 pts who underwent RP of CIED’s for MRI. Outcomes analyzed were safety parameters during RP. Results Of the 209 MRI scans, 51 scans were performed urgently. There were no connectivity and programming problems or need for MRI rescheduling. In-person reprogramming was not required for any pt. All scans were completed safely in a timely manner, and there were no reports of CIED malfunction. Conclusions Remote programming of CIED’s for MRI scans is a safe and effective strategy.


2021 ◽  
Vol 5 (8) ◽  
pp. 01-03
Author(s):  
Sajjad Ali Khan ◽  
Nanik Ram ◽  
Dania Ali ◽  
Muhammad Saleem

Hypothyroidism is a common endocrine disease which occurs when the levels of Thyroid hormones produced by the Thyroid gland are decreased. Here we present a case of a 19-year-old female, who presented with symptoms of hyperprolactinemia, weight gain, unilateral blurring of eyes and headache. Examination findings of the patient were significant for presence of Acanthosis Nigricans and Hirsutism. Rest of the systemic examination was normal. Laboratory investigations revealed Hyperprolactinemia, Hypothyroid profile and dyslipidemia. MRI brain and pituitary done showed findings consistent with Pituitary macroadenoma. Patient was treated along the lines of hypothyroidism with Thyroxine. Follow-up after 3 months showed improvement of her symptoms and disappearance of lesion of MRI scan. This case was a rare presentation of Hypothyroidism. Such unusual and uncommon presentations should be reported and studied in detail to prevent misdiagnosis and provide the correct treatment to the patients.


2021 ◽  
Author(s):  
Carolina Badke D'Andrea ◽  
Jeanette K. Kenley ◽  
David F. Montez ◽  
Amy E. Mirro ◽  
Ryland L. Miller ◽  
...  

Imaging the infant brain with MRI has improved our understanding of early stages of neurodevelopment. However, head motion during MRI acquisition is detrimental to both functional and structural MRI scan quality. Though infants are commonly scanned while asleep, they commonly exhibit motion during scanning, causing data loss. Our group has shown that providing MRI technicians with real-time motion estimates via Framewise Integrated Real-Time MRI Monitoring (FIRMM) software helps obtain high-quality, low motion fMRI data. By estimating head motion in real time and displaying motion metrics to the MR technician during an fMRI scan, FIRMM can improve scanning efficiency. Hence, we compared average framewise displacement (FD), a proxy for head motion, and the amount of usable fMRI data (FD ≤ 0.2mm) in infants scanned with (n = 407) and without FIRMM (n = 295). Using a mixed-effects model, we found that the addition of FIRMM to current state-of-the-art infant scanning protocols significantly increased the amount of usable fMRI data acquired per infant, demonstrating its value for research and clinical infant neuroimaging.


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