Pediatric nasal chondromesenchymal hamartomas: a case series.

PURPOSE: Nasal chondromesenchymal hamartomas (NCMH) are rare, predominantly benign tumors of the sinonasal tract. The distinction from higher grade malignancy may be challenging based on imaging features alone. To increase the awareness of this entity among radiologists, we present a multi-institutional case series of pediatric NCMH patients showing the varied imaging presentation. METHODS: Descriptive assessment of imaging appearances of the lesions on computed tomography (CT) and magnetic resonance imaging (MRI) was performed. In addition, we reviewed demographic information, clinical data, results of genetic testing, management, and follow-up data. RESULTS: Our case series consisted of 10 patients, with a median age of 0.5 months. Intraorbital and intracranial extensions were both observed in two cases. Common CT findings included bony remodeling, calcifications, and bony erosions. MRI showed heterogeneous expansile lesion with predominantly hyperintense T2 signal and heterogenous post-contrast enhancement in the majority of cases. Most lesions exhibited increased diffusivity on diffusion weighted imaging and showed signal drop-out on susceptibility weighted images in the areas of calcifications. Genetic testing was conducted in 4 patients, revealing the presence of DICER1 pathogenic variant in three cases. Surgery was performed in all cases, with one recurrence in two cases and two recurrences in one case on follow-up. CONCLUSION: NCMHs are predominantly benign tumors of the sinonasal tract, typically associated with DICER1 pathogenic variants and most commonly affecting pediatric population. They may mimic aggressive behavior on imaging; therefore, awareness of this pathology is important. MRI and CT have complementary roles in the diagnosis of this entity.

Machine learning assisted DSC-MRI radiomics as a tool for glioma classification by grade and mutation status.

BACKGROUND: Combining MRI techniques with machine learning methodology is rapidly gaining attention as a promising method for staging of brain gliomas. This study assesses the diagnostic value of such a framework applied to dynamic susceptibility contrast (DSC)-MRI in classifying treatment-naïve gliomas from a multi-center patients into WHO grades II-IV and across their isocitrate dehydrogenase (IDH) mutation status. METHODS: Three hundred thirty-three patients from 6 tertiary centres, diagnosed histologically and molecularly with primary gliomas (IDH-mutant = 151 or IDH-wildtype = 182) were retrospectively identified. Raw DSC-MRI data was post-processed for normalised leakage-corrected relative cerebral blood volume (rCBV) maps. Shape, intensity distribution (histogram) and rotational invariant Haralick texture features over the tumour mask were extracted. Differences in extracted features across glioma grades and mutation status were tested using the Wilcoxon two-sample test. A random-forest algorithm was employed (2-fold cross-validation, 250 repeats) to predict grades or mutation status using the extracted features. RESULTS: Shape, distribution and texture features showed significant differences across mutation status. WHO grade II-III differentiation was mostly driven by shape features while texture and intensity feature were more relevant for the III-IV separation. Increased number of features became significant when differentiating grades further apart from one another. Gliomas were correctly stratified by mutation status in 71% and by grade in 53% of the cases (87% of the gliomas grades predicted with distance less than 1). CONCLUSIONS: Despite large heterogeneity in the multi-center dataset, machine learning assisted DSC-MRI radiomics hold potential to address the inherent variability and presents a promising approach for non-invasive glioma molecular subtyping and grading.

Non-contrast computed tomography in the diagnosis of cerebral venous sinus thrombosis.

BACKGROUND: The aim of the study was to investigate the sensitivity and specificity of non-contrast computed tomography (NCCT) in the diagnosis of cerebral venous sinus thrombosis (CVST). Methods. Screening our neurological department database, we identified 53 patients who were admitted to neurological emergency department with clinical signs of CVST. Two independent observers assessed the NCCT scans for the presence of CVST. CT venography and/or MR venography were used as a reference standard. Interobserver agreement between the two readers was assessed using Kappa statistic. Attenuation inside the cerebral venous sinuses was measured and compared between the patient and the control group. RESULTS: CVST was confirmed in 13 patients. Sensitivity and specificity of NCCT for overall presence of CVST were 100% and 83%, respectively, with Kappa value of 0.72 (a good agreement between observers). The attenuation values between CVST patients and control group were significantly different (73.4 ± 14.12 HU vs. 58.1 ± 7.58 HU; p = 0.000). The ROC analysis showed an area under the curve (AUC) of 0.916 (95% CI, 0.827 - 1.00) and an optimal cutoff value of 64 HU, leading to a sensitivity of 85% and specificity of 87%. CONCLUSIONS: NCCT as a first-line investigation has a high value for diagnosis of CVST in the emergency setting. The additional measurement of the sinus attenuation may improve the diagnostic value of the examination.

Blood-brain barrier permeability imaging using perfusion computed tomography.

BACKGROUND: The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases. CONCLUSIONS: Blood-brain barrier permeability can be evaluated in vivo by perfusion computed tomography - an efficient diagnostic method that involves the sequential acquisition of tomographic images during the intravenous administration of iodinated contrast material. The major clinical applications of perfusion computed tomography are in acute stroke and in brain tumor imaging.

Retropharyngeal calcific tendinitis in the neurological emergency unit, report of three cases and review of the literature.

BACKGROUND: Retropharyngeal calcific tendinitis (RCT) is a relatively benign condition of calcination of the longus colli muscle tendon of unknown origin, which causes severe acute neck pain. However, it is often not recognised, which leads to delayed diagnosis and unnecessary treatment. PATIENTS AND METHODS: We have searched PubMed and Google Scholar for publications which reported at least one patient with RCT and were published in the last 20 years. The literature was then analysed according to the PRISMA-S protocol. We also report three patients with RCT presenting at the Neurological Emergency Unit, University Medical Centre, Ljubljana, Slovenia, from 1 January 2020 to 1 June 2022. We discuss their clinical presentation and differential diagnosis, explain our decision-making process, and briefly describe the clinical course. Case reports have been performed according to the CARE protocol. RESULTS: We have analysed a total of 112 titles with 231 patients. The most frequent symptoms and signs were: neck pain, neck stiffness and odynophagia, as was the case in our reported cases. CONCLUSIONS: RCT is a dramatic yet self-limiting condition, often not recognised in time. An effort should be made to increase neurologists' awareness about this condition.

ADC values as a biomarker of fetal brain maturation.

BACKGROUND: During the period of fetal development, myelination plays a key role and follows specific time and spatial sequences. The water content in the brain is inversely proportional to myelination - the more myelinated the brain, the lower the water content in it. The diffusion of water molecules can be quantitatively assessed using the apparent diffusion coefficient (ADC). We were interested in whether, by determining the ADC values, we could quantitatively evaluate the development of the fetal brain. PATIENTS AND METHODS: The study included 42 fetuses with gestational age 25 to 35 weeks. We manually selected 13 regions on diffusion-weighted images. Statistically significant differences between ADC values were checked using one-way analysis of variance and Tukey's post hoc test. The relationship between the ADC values and the gestational age of the fetuses was then assessed using linear regression. RESULTS: The average gestational age of the fetuses was 29.8 ± 2.4 weeks. ADC values in the thalami, pons and cerebellum differed significantly among each other and from the ADC values in other brain regions. In the thalami, pons and cerebellum, linear regression showed a significant decrease in ADC values with increasing gestational age. CONCLUSIONS: ADC values change with the increasing gestational age of the fetus and differ among different brain regions. In the pons, cerebellum and thalami, the ADC coefficient could be used as a biomarker of fetal brain maturation since ADC values decrease linearly with increasing gestational age.

Independent Significance of Visual Assessment of Perfusion CT Maps in Anterior Circulation Stroke Patients Treated with Mechanical Thrombectomy.

BACKGROUND: In the absence of an automated software analysis, the role of computed tomography perfusion (CTP) in a real time clinical practice is not well established. We evaluated the clinical significance of a widely accessible and simple visual grading scale of CTP in the anterior circulation of acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT). METHODS: The single center consecutive CT investigations of AIS patients treated with MT in the anterior circulation have been evaluated retrospectively. ASPECT score and collateral circulation evaluation based on the Maas score were determined. Time to peak parametric maps, derived from CTP, were graded into four categories, from least to most favorable. The primary endpoint was functional outcome evaluated as modified Rankin Scale (mRS) ≤ 2 at 90 days after MT. RESULTS: We included 318 patients in the analysis; 142 (45%) patients had mRS ≤ 2 after 90 days, mortality rate was 24%. Higher CTP and Maas score were significantly correlated with better clinical outcome (Pearson χ2 25.0 and 37.7, respectively; p < 0.01). Collateral circulation and CTP grades were strongly interrelated (Pearson χ2 78.6; p < 0.01). The CTP grade demonstrated statistically significant independent correlation with the clinical outcome irrespective of the collateral circulation grade, ASPECT score and age (OR 2.5; p = 0.011). The correlation was more pronounced in patients with normal collateral circulation (OR 3.27; p = 0.029). CONCLUSION: We demonstrated that both visually graded CTP and collateral circulation grade strongly correlated with the clinical outcome of MT in the anterior circulation of AIS patients. Importantly, CTP correlated with the clinical outcome independent of the collateral circulation.

Auditory agnosia with anosognosia.

A 66-year-old right-handed female medical doctor suffered two consecutive cardioembolic strokes, initially affecting the right frontal lobe and the right insula, followed by a lesion in the left temporal lobe. The patient presented with distinctive phenomenology of general auditory agnosia with anosognosia for the deficit. She did not understand verbal requests and her answers to oral questions were fluent but unrelated to the topic. However, she was able to correctly answer written questions, name objects, and fluently describe their purpose, which is characteristic for verbal auditory agnosia. She was also unable to recognise environmental sounds or to recognise and repeat any melody. These inabilities represent environmental sound agnosia and amusia, respectively. Surprisingly, she was not aware of the problem, not asking any questions regarding her symptoms, and avoiding discussing her inability to understand spoken language, which is indicative of anosognosia. The deficits in our patient followed a distinct pattern of recovery. The verbal auditory agnosia was the first to resolve, followed by environmental sound agnosia. Amusia persisted the longest. The patient was clinically assessed from the first day of symptom onset and the evolution of symptoms was video documented. We give a detailed account of the patient's behaviour and provide results of audiological and neuropsychological evaluations. We discuss the anatomy of auditory agnosia and anosognosia relevant to the case. This case study may serve to better understand auditory agnosia in clinical settings. It is important to distinguish auditory agnosia from Wernicke's aphasia, because use of written language may enable normal communication.

Prognostic value of CT perfusion and permeability imaging in traumatic brain injury.

BACKGROUND: Currently established prognostic models in traumatic brain injury (TBI) include noncontrast computed tomography (CT) which is insensitive to early perfusion alterations associated with secondary brain injury. Perfusion CT (PCT) on the other hand offers insight into early perfusion abnormalities. We hypothesized that adding CT perfusion and permeability data to the established outcome predictors improves the performance of the prognostic model. METHODS: A prospective cohort study of consecutive 50 adult patients with head injury and Glasgow Coma Scale score of 12 or less was performed at a single Level 1 Trauma Centre. Perfusion CT was added to routine control CT 12 hours to 24 hours after admission. Region of interest analysis was performed in six major vascular territories on perfusion and permeability parametric maps. Glasgow Outcome Scale (GOS) was used 6 months later to categorize patients' functional outcomes to favorable (GOS score > 3) or unfavorable (GOS score ≤ 3). We defined core prognostic model, consisting of age, motor Glasgow Coma Scale score, pupillary reactivity, and CT Rotterdam Score. Next, we added perfusion and permeability data as predictors and compared updated models to the core model using cross-validated areas under the receiver operator curves (cv-AUC). RESULTS: Significant advantage over core model was shown by the model, containing both mean cerebral extravascular-extracellular volume per unit of tissue volume and cerebral blood volume of the least perfused arterial territory in addition to core predictors (cv-AUC, 0.75; 95% confidence interval, 0.51-0.84 vs. 0.6; 95% confidence interval, 0.37-0.74). CONCLUSION: The development of cerebral ischemia and traumatic cerebral edema constitutes the secondary brain injury and represents the target for therapeutic interventions. Our results suggest that adding CT perfusion and permeability data to the established outcome predictors improves the performance of the prognostic model in the setting of moderate and severe TBI. LEVEL OF EVIDENCE: Prognostic study, level III.

Access From Above-Bailout Solution for Intraoperative Distal Migration of Abdominal Aortic Stent Graft.

The majority of the ruptured abdominal aortic aneurysms today is treated endovascularly. In cases with short aneurysm neck, chimney technique can be used to extend landing zone in emergency setting. Additionally, the repositioning ability of C3 delivery system (Gore & Associates) allows better positioning in cases with challenging anatomy. In our experience, proximal reposition of partially deployed device can be problematic in some patients. We present a case of endovascular repair of ruptured abdominal aortic aneurysm using chimney technique where proximal reposition was achieved by snaring the aortic device via axillary access.

Presence of central veins and susceptibility weighted imaging for evaluating lesions in multiple sclerosis and leukoaraiosis.

PURPOSE: The process of demyelination in multiple sclerosis (MS) is reflected in lesions of the central nervous system (CNS), which are found in an abundance of different diseases and are frequently radiographically indistinguishable. Our aim was to determine whether the perivenous distribution of MS lesions identified on susceptibility weighted images (SWI) could be used as a specific radiographic sign for MS, and also to determine whether the visibility of the central vein (CV) is affected by the activity of MS lesions. METHODS: We retrospectively examined 34 subjects with MS and 19 subjects with ischemic lesions, which underwent a 3T MRI investigation. According to FLAIR and T2-weighted sequences the lesions were categorized regarding location. The presence of CVs was determined on SWI. Gadolinium enhanced T1-weighted sequence was included for the evaluation of MS lesion activity. RESULTS: A total load of 601 MS and 204 ischemic lesions was identified. We found significantly more lesions with CVs in the group with ischemic lesions compared to the group with MS lesions (p<0.001). Similarly, significantly more supratentorial peripheral ischemic lesions had CVs (p=0.011), whereas in supratentorial periventricular and intratentorial lesions we found no significant difference between the two groups (p=0.377 and p=0.615). Comparing the active and inactive MS lesions regarding CVs, we found no significant difference between the groups (p=0,472). CONCLUSIONS: We can conclude that the presence of a CV is not a specific radiographic sign for MS. CVs can also be identified in lesions caused by various other diseases.

Endovascular embolization prior to surgical resection of symptomatic intralobar pulmonary sequestration in an adult.

Intralobar pulmonary sequestration is a rare congenital malformation, conventionally managed by surgical resection. Recently, the endovascular embolization has been proposed for the definite treatment of this disease. Additionally, preoperative embolization of aberrant arteries to minimize the risk of serious intraoperative haemorrhage has also been described. We report the case of 43-year old female patient who presented with cough and haemoptysis, and was successfully treated with endovascular embolization followed by a Video-assisted thoracoscopic wedge resection.