Extraprostatic Seed Placement and Its Effect on Seed Loss

We sought to examine the intra- and interobserver variability in measuring the cochlear duct length (CDL) from magnetic resonance imaging (MRI) images versus computed tomography (CT) images using an otological surgical planning software that uses measurements of the basal turn diameter and cochlear width to estimate the CDL. Twenty-one adult cochlear implant patients with preoperative MRI and CT images. Three fellowship-trained neurotologists served as the raters in the study. One rater measured the CDL using preoperative CT scans to serve as the benchmark. Two of the raters measured the CDL on preoperative MRI scans. One rater also remeasured the scans using MRI images after a period of 1 week to assess intraobserver variability. Intraclass correlational coefficients were calculated to assess for intra- and interobserver agreement. The mean CDL measured from the CT scans was 32.7 ± 2.0 mm (range 29.4 - 37.6 mm). The mean difference between the raters when measuring the CDL using MRI scans was -0.15 ± 2.1 mm (range -3.2 to 4.3 mm). The intraclass correlational coefficients for inter-rater reliability of CDL determination using MRI scans was judged as fair to excellent (0.68; 95% CI 0.41-0.84). The intrarater reliability of CDL determination using MRI scans was judged at fair to excellent (0.73; 95% CI 0.491-0.866). We demonstrate that a validated otological surgical planning software for estimating the CDL preoperatively had comparable performance using MRI scans versus the gold-standard CT scans.

Optimal Measurement Modality and Method for Evaluation of Responses to Transarterial Chemoembolization of Hepatocellular Carcinoma Based on Enhancement Criteria

Requests for computed tomography (CT) and magnetic resonance imaging (MRI) scans by doctors with different levels of experience have cost and risk implications globally. Evidence-based appropriateness criteria guide doctors to the suitable use of radiology imaging. There are few studies regarding appropriateness of CT requests in the South African (SA) context. Previous research in the Garden Route district of Western Cape Province, SA, evaluated the appropriateness of scans. To review the appropriateness of CT and MRI scans done in a 6-year follow-up study at one facility. This was a retrospective descriptive study. All CT and MRI scans performed during October 2018 at George Hospital were classified according to American College of Radiology guidelines as: usually appropriate (UA), might be appropriate (MBA), or not appropriate (NA). Stratified analysis allowed simple statistics and some comparison with the previous study. A total of 515 CT and MRI scans were included, of which 81.4% were UA, 7.4% MBA and 11.2% NA. Most scans were requested by medical officers (n=255), followed by consultants (n=126) and junior doctors (n=70). Medical officers made the majority of inappropriate requests. Second-year interns requested the lowest number of inappropriate scans, with registrars not requesting any inappropriate scans. Most of the inappropriate scans were requested after hours. Thirty-seven of the 123 (30.1%) after-hours scans were inappropriately requested compared with 21 of 392 (5.4%) scans during normal working hours, which were inappropriate. Although the majority of scans were being ordered appropriately, pre-authorisation by experienced physicians and incorporation of guidelines would make requests more complete and possibly more appropriate, especially after hours.

Purpose: To analyze the error in contouring the brainstem for patients with head and neck cancer who underwent radiotherapy based on computed tomography (CT) and magnetic resonance (MR) images. Methods: 20 brain tumor and 17 nasopharyngeal cancer patients were randomly selected. Each patient underwent MR and CT scanning. For each patient, one observer contoured the brainstem on CT and MR images for 10 times, and 10 observers from five centers delineated the brainstem on CT and MR images only one time. The inter- and intra-observers volume and outline variations were compared. Results: The volumes of brainstem contoured by inter- and intra-observers on CT and MR images were similar (p>0.05). The reproducibility of contouring brainstem on MR images was better than that on CT images (p<0.05) for both inter- and intra-observer variability. The inter- and intra-observer for contouring on CT images reached mean values of 0.81±0.05 (p>0.05) and of 0.85±0.05 (p>0.05), respectively, while on MR images these respective values were 0.90±0.05 (p>0.05) and 0.92±0.04 (p>0.05). Conclusion: Contouring the brainstem on MR images was more accurate and reproducible than that on CT images. Precise information might be more helpful for protecting the brainstem radiation injury the patients whose lesion were closed to brainstem.

Metastases of thyroid carcinomas to the choroid and/or orbit are infrequent. PubMed was searched for English-language articles and case reports published from 1977 to 2012. In our survey, we looked for reports of orbital and/or ocular metastases from the thyroid and found 31 reported cases from 1979 to 2012. At the time of onset of ocular symptoms, the vast majority of patients had a long history of thyroid malignancy and evidence of widely disseminated metastatic disease. The age of the reported patients ranged from 29 to 83 years. Among the 22 reported cases of thyroid carcinomas with metastases to the choroid from 1979 to 2012, the most common primary tumor was papillary thyroid carcinoma (PTC); this occurred in seven patients. This was followed by medullary thyroid carcinoma in six cases and follicular thyroid carcinoma (FTC) in five cases. Orbital metastases were reported in nine patients with thyroid carcinomas (PTC=4, FTC=3, Hürthle cell=1, not specified=1). Patients with choroidal metastases presented with decreased or blurred vision, eye pain, and flashes in 81%, 5%, and 5% of cases, respectively. The diagnosis of a choroidal tumor was usually based on noninvasive diagnostic techniques such as ultrasonography, transillumination, computer tomography (CT), and/or magnetic resonance imaging (MRI) scanning. ¹³¹I scanning revealed uptake in the orbit in 26% of cases with choroidal and/or orbital PTC or FTC. For a metastasis that causes a definitive loss of vision and/or persistent pain, the treatment of choice was enucleation. The other treatment options were brachyradiotherapy using ¹²⁵I episcleral radioactive plaque insertion, external beam radiation, ¹³¹I therapy, chemotherapy, and/or targeted therapy with small molecules. The orbit and globe are not common sites for metastatic thyroid carcinomas. Diagnosis of a choroidal tumor is usually based on clinical judgment and results of noninvasive diagnostic techniques such as ultrasonography, transillumination, CT, and/or MRI scanning. Fundoscopic examination and ocular ultrasonography by an ophthalmologist are recommended for identification and monitoring of choroidal metastatic deposits.

Background and purpose It is difficult to evaluate glenoid component periprosthetic radiolucencies in total shoulder arthroplasties (TSAs) using plain radiographs. This study was performed to evaluate whether computed tomography (CT) using a specific patient position in the CT scanner provides a better method for assessing radiolucencies in TSA.Methods Following TSA, 11 patients were CT scanned in a lateral decubitus position with maximum forward flexion, which aligns the glenoid orientation with the axis of the CT scanner. Follow-up CT scanning is part of our routine patient care. Glenoid component periprosthetic lucency was assessed according to the Molé score and it was compared to routine plain radiographs by 5 observers.Results The protocol almost completely eliminated metal artifacts in the CT images and allowed accurate assessment of periprosthetic lucency of the glenoid fixation. Positioning of the patient within the CT scanner as described was possible for all 11 patients. A radiolucent line was identified in 54 of the 55 observed CT scans and osteolysis was identified in 25 observations. The average radiolucent line Molé score was 3.4 (SD 2.7) points with plain radiographs and 9.5 (SD 0.8) points with CT scans(p = 0.001). The mean intra-observer variance was lower in the CT scan group than in the plain radiograph group (p = 0.001).Interpretation The CT scan protocol we used is of clinical value in routine assessment of glenoid periprosthetic lucency after TSA. The technique improves the ability to detect and monitor radiolucent lines and, therefore, possibly implant loosening also.

BackgroundWe evaluated the accuracy of magnetic resonance imaging (MRI) computed tomography (CT)-like sequences compared to normal-resolution CT (NR-CT) and super-high-resolution CT (SHR-CT) for planning of cochlear implantation.MethodsSix cadaveric temporal bone specimens were used. 3-T MRI scans were performed using radial volumetric interpolated breath-hold (STARVIBE), pointwise-encoding time reduction with radial acquisition (PETRA), and ultrashort time of echo (UTE) sequences. CT scans were performed on two scanners for SHR-CT and NR-CT acquisitions. Two radiologists evaluated accuracy based on preimplantation metrics and the ability to identify various anatomical structures, particularly the facial recess and round window. Wilcoxon rank-sum test and intraclass correlation coefficient (ICC) were used.ResultsThe facial nerve was always clearly visible (score ≥ 2) in the MRI, NR-CT, and SHR-CT scans (p ≥ 0.621). However, the chorda tympani nerve (CTN) was clearly visualized in UTE, STARVIBE, and PETRA sequences in only 33% (2/6 specimens, p = 0.016), 50% (3/6 specimens, p = 0.038), and 83% (5/6 specimens, p = 0.017) of cases, respectively, whereas it was always clearly visualized in SHR and NR-CT (p = 0.426). The round window (RW) was never visualized in MRI sequences (p ≤ 0.010), whereas it was identified in all cases in SHR and NR-CT (p = 1.000). There was a strong correlation between measurements obtained from MRI and CT modalities (ICC ≥ 0.837).ConclusionMRI CT-like sequences assessed the facial nerve in all cases and the CTN in up to 87% of cases. However, the detection of the RW was insufficient for surgical planning. CT and MRI measurements were in agreement.Relevance statementCT-like MRI sequences can image the anatomy of the facial recess and the length of the basal turn of the cochlea with similar accuracy as conventional CT, although they cannot image the round window.Key PointsCT-like MRI sequences are not widely used in preoperative cochlear implantation imaging.CT-like sequences can image the facial recess as well as conventional CT.CT-like sequences can image the basal turn length of the cochlea as well as conventional CT.Round window depiction is not possible with CT-like MRI sequences.Graphical

Survey of cases. To evaluate the opinion of experts in the diagnostic process of clinically relevant Spinal Post-traumatic Deformity (SPTD). SPTD is a potential complication of spine trauma that can cause decreased function and quality of life impairment. The question of when SPTD becomes clinically relevant is yet to be resolved. The survey of 7 cases was sent to 31 experts. The case presentation was medical history, diagnostic assessment, evaluation of diagnostic assessment, diagnosis, and treatment options. Means, ranges, percentages of participants, and descriptive statistics were calculated. Seventeen spinal surgeons reviewed the presented cases. The items' fracture type and complaints were rated by the participants as more important, but no agreement existed on the items of medical history. In patients with possible SPTD in the cervical spine (C) area, participants requested a conventional radiograph (CR) (76%-83%), a flexion/extension CR (61%-71%), a computed tomography (CT)-scan (76%-89%), and a magnetic resonance (MR)-scan (89%-94%). In thoracolumbar spine (ThL) cases, full spine CR (89%-100%), CT scan (72%-94%), and MR scan (65%-94%) were requested most often. There was a consensus on 5 out of 7 cases with clinically relevant SPTD (82%-100%). When consensus existed on the diagnosis of SPTD, there was a consensus on the case being compensated or decompensated and being symptomatic or asymptomatic. There was strong agreement in 5 out of 7 cases on the presence of the diagnosis of clinically relevant SPTD. Among spine experts, there is a strong consensus to use CT scan and MR scan, a cervical CR for C-cases, and a full spine CR for ThL-cases. The lack of agreement on items of the medical history suggests that a Delphi study can help us reach a consensus on the essential items of clinically relevant SPTD. Level V.

The 20 members of the Western Australian fast bowling development squad (mean age, 17.9 years), who had previously undergone routine computed tomography (CT) and magnetic resonance imaging (MRI) scans to detect the presence of bony and intervertebral disk abnormalities, acted as subjects for this study. While these radiologic data were being analyzed, these players were filmed both laterally (200 Hz) and from directly above (100 Hz) as their front foot impacted a force platform during the delivery stride of the fast bowling action. On a subsequent trial, kinetic data from the platform were recorded when their back foot impacted the force platform. In addition, these bowlers performed selected physical capacity tests. The occurrence of abnormal radiologic data were then used to group the bowlers (group 1: no abnormal radiologic features from CT or MRI scans; group 2: disk degeneration or bulging on MRI scan; group 3: spondylolysis, spondylolisthesis, or pedicle sclerosis). A Mann‐Whitney U‐rank test was th...

The aim of this work was to assess two issues concerning magnetic resonance imaging (MRI) including device functionality and image artifacts for the presence of ultra high frequency (UHF) radio frequency identification (RFID) devices in connection with 0.3 Tesla at 12.7 MHz MRI and computed tomography (CT) scanning. A total of 15 samples of RFID tags with two dissimilar sizes (wristband and ID card types) were tested. The tags were exposed to a several numbers of MR-imaging conditions during MRI examination and X-rays of CT scan. During the test, the tags were oriented in three different directions (axial, coronal and sagittal) pertaining to MRI system in order to encompass all possible situations with respect to the patient undergoing MRI and CT scanning, wearing a RFID tag on wrist. In addition to the device functionality test and imaging artifacts, we also analyzed the reading performance of the RFID reader considering significant factors in MRI scan area. We observed that the tags did not experience physical damage with its functionality remained unchanged even after MRI and CT scanning, and there was no modification in previously stored data as well. In addition, no evidence of artifact was observed in the acquired MR and CT images. Therefore, we can conclude that the use of passive UHF RFID tag is safe for a patient undergoing MRI at 0.3 T/12.7 MHz and CT scanning. However, the reading performance of the RFID reader got affected depending on whether the MRI machine was on or off and also by the angle of the reader antenna.

Salter-Harris (SH) III fractures of the distal femur, although rare, can have devastating effects. The purposes of this study were to: (1) compare the intra-articular fracture displacement measured on plain x-ray and magnetic resonance imaging (MRI) or computed tomography (CT) scan and (2) report the outcomes of patients with a SH III fracture of the distal femur. All SH III distal femur fractures treated at a large Children's Hospital with a Level I Pediatric Trauma Center between 1995 and 2006 were retrospectively reviewed. A total of 14 patients (average age: 13 y, 11 mo; range: 7 y, 8 mo to 17 y, 11 mo) with an average follow-up time of 21.50 months (range: 2 to 47 mo) were included in this study. Fracture displacement on plain x-ray was compared with the fracture displacement measured on MRI or CT scan. The average time between the initial plain x-ray and MRI or CT scan was 37.48 days (range: 3 h to 6 mo). Plain x-rays significantly underestimated the displacement of SH III fractures versus MRI or CT scan. Six patients who had both plain x-ray and MRI or CT scan had a measured displacement of 0.42 mm and 2.70 mm, respectively (paired Student t test, P=0.005). Ten of the 14 patients (71%) had no physical limitations and full knee motion at their most recent follow-up visit. The treatment of 4 patients (29%) was changed based on the findings of the additional MRI or CT scan. This study and earlier studies have shown a high rate of poor results with SH III fractures of the distal femur. This type of fracture pattern is extremely unstable and the true displacement is often underestimated by x-rays. Thus, it is strongly recommended that an MRI or CT scan be obtained on every SH III fracture of the distal femur. Moreover, any SH III fracture visible on plain radiographs should be treated with open reduction, internal fixation. Level IV.

Cocaine use is associated with multiple neurovascular complications, including ischemic and hemorrhagic strokes. Intracerebral hemorrhage is especially prevalent in patients with acute cocaine intoxication as defined by positive urine toxin assays.1 In addition, intracerebral hemorrhage in patients with cocaine intoxication are more severe, often associated with intraventricular hemorrhage, and have a poorer prognosis than intracerebral hemorrhage from other causes.2 Still, the majority of patients with cocaine-associated strokes will present with ischemic strokes. Whether intravenous tissue-type plasminogen activator (tPA) can be safely used in patients presenting with ischemic strokes and recent cocaine use is unknown, and their risk toward hemorrhagic conversion is not fully characterized. We describe 2 cases of cocaine-associated ischemic stroke with immediate hemorrhagic transformation after intravenous tPA infusion. A 55-year-old man presented to the emergency department 20 minutes after the sudden onset of left arm weakness while using cocaine. Examination revealed left hemiparesis-hemiataxia and noncontrast head computed tomography (CT) was normal except for bilateral white matter hypointensities suggestive of leukoaraiosis and a nasal septum perforation indicative of chronic intranasal cocaine use (Figure 1). A bolus of intravenous tPA was administered for acute ischemic stroke, with a symptom onset to administration time of 45 minutes. During the intravenous tPA infusion, the systolic blood pressure remained below 170 mm Hg. Immediately after the tPA bolus infusion, a CT-angiogram and postcontrast CT were acquired (Figure 1B). While being transported to the neuro-ICU, the patient complained of new headache and right arm weakness before quickly progressing to coma requiring emergent intubation as tPA infusion completed. Review of initial studies revealed contrast extravasation in the dorsal pons during tPA infusion (Figure 1B, black arrow). A magnetic resonance imaging scan revealed multifocal infarcts and hemorrhages raising suspicion for …

To evaluate the performance of Microsoft Bing with ChatGPT-4 technology in analyzing abdominal computed tomography (CT) and magnetic resonance images (MRI). A comparative and descriptive analysis was conducted using the institutional picture archiving and communication systems. A total of 80 abdominal images (44 CT, 36 MRI) that showed various entities affecting the abdominal structures were included. Microsoft Bing's interpretations were compared with the impressions of radiologists in terms of recognition of the imaging modality, identification of the imaging planes (axial, coronal, and sagittal), sequences (in the case of MRI), contrast media administration, correct identification of the anatomical region depicted in the image, and detection of abnormalities. Microsoft Bing detected that the images were CT scans with 95.4% accuracy (42/44) and that the images were MRI scans with 86.1% accuracy (31/36). However, it failed to detect one CT image (2.3%) and misidentified another CT image as an MRI (2.3%). On the other hand, it also misidentified four MRI as CT images (11.1%) and one as an X-ray (2.7%). Bing achieved an 83.75% success rate in correctly identifying abdominal regions, with 90% accuracy for CT scans (40/44) and 77.7% for MRI scans (28/36). Concerning the identification of imaging planes, Bing achieved a success rate of 95.4% for CT images and 83.3% for MRI. Regarding the identification of MRI sequences (T1-weighted and T2-weighted), the success rate was 68.75%. In the identification of the use of contrast media for CT scans, the success rate was 64.2%. Bing detected abnormalities in 35% of the images but achieved a correct interpretation rate of 10.7% for the definite diagnosis. While Microsoft Bing, leveraging ChatGPT-4 technology, demonstrates proficiency in basic task identification on abdominal CT and MRI, its inability to reliably interpret abnormalities highlights the need for continued refinement to enhance its clinical applicability. The contribution of large language models (LLMs) to the diagnostic process in radiology is still being explored. However, with a comprehensive understanding of their capabilities and limitations, LLMs can significantly support radiologists during diagnosis and improve the overall efficiency of abdominal radiology practices. Acknowledging the limitations of current studies related to ChatGPT in this field, our work provides a foundation for future clinical research, paving the way for more integrated and effective diagnostic tools.

Ten patients who had undergone leg lengthening were monitored with plain radiographs and computed tomography (CT) scans at 3-month intervals. Four of them were examined with magnetic resonance imaging (MRI) scans. When the external fixator was removed, MRI scans could not demonstrate any continuous fat signals in the lengthened region, suggesting the lack of medullary cavity. CT scans disclosed double cortex in three patients and irregular new bone formation in seven. At 6 months, a medullary cavity could be detected. Other aberrations were less evident. Remodeling of new bone material required at least 1 year.

Alzheimer’s disease (AD) is a chronic and progressive neurological condition that predominantly affects older adults by deteriorating cognitive abilities. Detecting AD at an early stage is essential for timely medical care and to delay further decline. This research introduces a multimodal deep learning framework designed to identify Alzheimer’s using both Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) data. The system incorporates transfer learning along with an early fusion mechanism to maximize diagnostic precision.For feature extraction, the model utilizes the ResNet50 architecture on MRI scans and EfficientNetB0 on CT scans, effectively capturing both anatomical and vascular characteristics relevant to AD. The extracted features are combined through concatenation before passing to the classification stage, where the integration of heterogeneous features contributes to enhanced detection accuracy. The dataset comprises labeled MRI and CT scan images from open-access Kaggle sources, including categories for ModerateDemented and Nondemented subjects.The model is optimized using the Adam optimizer and trained with a binary cross-entropy loss function in a two-class classification setup. ReLU activation functions are applied within the deep networks, while a sigmoid function handles the final output layer. Experimental evaluations confirm that fusing MRI and CT modalities outperforms individual image inputs, emphasizing the promise of multimodal deep learning models for accurate and early AD detection, especially in resource-constrained clinical settings.