Degree Of Contrast Enhancement Research Articles

조영증강 복부 CT 검사에서 조영제 사용량 감소에 관한 연구

In our hospital, we implement a reduction in contrast media dose (calculated as body weight × 1.2 mL) for clinical examinations conducted with dual-source dual-energy CT during contrast-enhanced abdominal CT examinations. Therefore, by applying the CE-Boost technique, the degree of contrast enhancement of blood vessels and tissues was compared with standard contrast media dose (body weight × 1.6 mL) in 120 kV single-source computed tomography images. In contrast-enhanced abdominal CT using the standard contrast media dose, the CE-Boost technique was applied to investigate the feasibility of reducing the contrast media dose. From January 2023, a retrospective study was conducted on 62 subjects. The study included an experimental group (A) that received a reduced contrast media dose, an experimental group + CE-Boost (B), and a control group (C) that received the standard contrast media dose. For quantitative evaluation, in the image where the Main Portal Vein (MPV) is the widest, CT number (HU), Signal-to-Noise Ratio (SNR), and Contrast-to-Noise Ratio (CNR) were calculated. Qualitative evaluation was independently assessed by five experienced radiotechnologists, who evaluated 10 samples as the assessment items for contrast enhancement and overall image quality. In the HU values, the (B) group with CE-Boost technique showed the highest value (P < .05), while the (A)-(C) group without CE-Boost technique showed no statistically significant difference. In the SNR, the group (B) that received the CE-Boost technique exhibited the highest value,(P<.05) but there was no significant difference compared to the group (C) that did not receive the CE-Boost technique in the evaluation of liver parenchyma.(P>.05) In CNR, the (B) group utilizing the CE-Boost technique showed the highest value (P<.05), but there was no statistically significant difference between (B) and (C). In the qualitative evaluation, the group (B) to which CE-Boost was applied was rated the highest in two evaluation items. If an AI-based CE-Boost technique is used for contrast-enhanced abdominal CT, it is believed that safe medical services can be provided to patients by implementing a 25% reduction in the standard contrast media dose while still maintaining image quality, even in a single-source 120kV CT.

Astrocytomas of the spinal cord.

Tumors of astrocytic origin represent one of the most frequent entities among the overall rare group of spinal cord gliomas. Initial clinical symptoms are often unspecific, and sensorimotor signs localizing to the spinal cord occur with progressing tumor growth. On MRI, a hyperintense intrinsic spinal cord signal on T2-weighted sequences with varying degrees of contrast enhancement raises suspicion for an infiltrative neoplasm. Blood and CSF analysis serves to exclude an infectious process, nutritional deficits, or metabolic disorders. When such other differential diagnoses have been ruled out, a neuropathological tissue-based analysis is warranted to confirm the diagnosis of a spinal cord astrocytoma and guide further patient management. As such, maximal safe resection forms the basis of any treatment. Meticulous preoperative planning is necessary to weigh the potential improvement in survival against the risk of functional deterioration. Intraoperative neuromonitoring and ultrasound may aid in achieving a more extensive resection. Depending on the assigned WHO tumor grade spanning from grade 1 to grade 4, the use of radiotherapy and chemotherapy might be indicated but also wait-and-scan approaches appear reasonable in tumors of lower grade. Close imaging follow-up is necessary given that recurrence inevitably occurs in astrocytomas of grades 2-4. Prognosis is so far dictated by tumor grade and histopathological findings, but also by age and clinical performance of the patient. Targeted therapies resting upon an in-depth tissue analysis are emerging in recurrent tumors, but no prospective study is available so far given the rarity of spinal cord astrocytomas.

Neurological manifestations in dogs with acute leukemia.

Canine acute leukemia is a rare hematopoietic neoplasm. Neurological abnormalities have been frequently reported in dogs with acute leukemia (AL). However, the description of the presentation and findings are limited. This study aimed to describe the clinical findings in dogs with acute leukemia presenting with neurological signs as their primary complaint. The database of a private referral hospital was searched for cases that presented to the neurological department with neurological deficits and were subsequently diagnosed with acute leukemia. Six cases were included; all had neurological clinical signs and an abnormal neurological examination. All cases had a focal neuroanatomical localisation on neurological examination (brain n = 4; spinal = 2). Out of the four dogs with a complete magnetic resonance imaging (MRI) study, there was an ill-defined infiltrative pattern with abnormal signal intensity in the central nervous system (CNS) in three dogs and the loss of grey and white matter differentiation in the brain (n = 2) and/or spinal cord (n = 2). Other MRI findings included abnormal meningeal enhancement (n = 3), changes affecting spinal nerves and epaxial muscles (n = 2), and lymphadenopathy in the field of view (n = 2). The bone marrow assessment on MRI showed evidence of signal change (n = 3), characterized by a loss of normal fat opacity and an abnormal degree of contrast enhancement. The cerebrospinal fluid (CSF) analysis of the four dogs showed an increased protein level with non-specific pleocytosis and without evidence of malignant cells. Treatment with cytotoxic medication was implemented in two dogs. The dogs diagnosed with acute leukemia had focal neuroanatomical localisation, an infiltrative CNS pattern, and bone marrow remodulation on MRI with an increase in CSF protein and negative cytology analysis.

Pancreas CT assessment for pancreatic ductal adenocarcinoma resectability: effect of tube voltage and slice thickness on image quality and diagnostic performance

ObjectivesTo assess the resectability of pancreatic ductal adenocarcinoma (PDAC), the evaluation of tumor vascular contact holds paramount significance. This study aimed to compare the image quality and diagnostic performance of high-resolution (HR) pancreas computed tomography (CT) using an 80 kVp tube voltage and a thin slice (1 mm) for assessing PDAC resectability, in comparison with the standard protocol CT using 120 kVp.MethodsThis research constitutes a secondary analysis originating from a multicenter prospective study. All participants underwent both the standard protocol pancreas CT using 120 kVp with 3 mm slice thickness (ST) and HR-CT utilizing an 80 kVp tube voltage and 1 mm ST. The contrast-to-noise ratio (CNR) between parenchyma and tumor, along with the degree of enhancement of the abdominal aorta and main portal vein (MPV), were measured and subsequently compared. Additionally, the likelihood of margin-negative resection (R0) was evaluated using a five-point scale. The diagnostic performance of both CT protocols in predicting R0 resection was assessed through the area under the receiver operating characteristic curve (AUC).ResultsA total of 69 patients (37 males and 32 females; median age, 66.5 years) were included in the study. The median CNR of PDAC was 10.4 in HR-CT, which was significantly higher than the 7.1 in the standard CT (P=0.006). Furthermore, HR-CT demonstrated notably higher median attenuation values for both the abdominal aorta (579.5 HU vs. 327.2 HU; P=0.002) and the MPV (263.0 HU vs. 175.6 HU; P=0.004) in comparison with standard CT. Following surgery, R0 resection was achieved in 51 patients. The pooled AUC for HR-CT in predicting R0 resection was 0.727, slightly exceeding the 0.699 of standard CT, albeit lacking a significant statistical distinction (P=0.128).ConclusionWhile HR pancreas CT using 80 kVp offered a notably greater degree of contrast enhancement in vessels and a higher CNR for PDAC compared to standard CT, its diagnostic performance in predicting R0 resection remained statistically comparable.

Magnetic Resonance Imaging Features for Differentiating Low-Grade and High-Grade Malignant Peripheral Nerve Sheath Tumors.

This study aimed to assess the usefulness of magnetic resonance imaging (MRI) findings for differentiating low-grade and high-grade malignant peripheral nerve sheath tumors (MPNSTs). This study included 31 patients (onset age range, 19-83 years; mean onset age, 57 years; 9 men and 22 women) with 36 histopathologically proven MPNSTs (7 low-grade MPNSTs and 29 high-grade MPNSTs) who underwent preoperative MRI between December 2007 and October 2022. Quantitative and qualitative MRI findings were retrospectively evaluated and compared between the 2 subtypes. The maximum tumor diameter (106.1 ± 64.0 vs 54.9 ± 19.8 mm, P = 0.032) and tumor-to-muscle signal intensity ratio (SIR) of fat-suppressed gadolinium-enhanced T1-weighted images (2.69 ± 1.40 vs 1.62 ± 0.40, P = 0.005) were significantly higher in high-grade MPNSTs than in low-grade MPNSTs. The receiver operating characteristic analysis revealed that the tumor-to-muscle SIR of fat-suppressed gadolinium-enhanced T1-weighted images exhibited the highest area under the curve value (0.88), followed by the maximum tumor diameter (0.76). The sensitivity and specificity of the tumor-to-muscle SIR of fat-suppressed gadolinium-enhanced T1-weighted images for diagnosing high-grade MPNST at an optimal SIR threshold of greater than 1.73 were 90% and 83%, respectively. However, other MRI findings showed no significant differences between the 2 subtypes ( P = 0.16-1.00). Although the MRI findings of low-grade and high-grade MPNST overlapped considerably, the maximum tumor diameter and degree of contrast enhancement can be used to differentiate low-grade MPNST from high-grade MPNST.

Association of Decreased Enhancement of Nasoseptal Flap on Postoperative Magnetic Resonance Imaging with the Risk of Complication.

Objectives Our objective was to determine if decreased contrast enhancement on postoperative magnetic resonance imaging (MRI) is associated with an increased risk of complication in patients who have undergone nasoseptal flap (NSF) reconstruction. Design/Setting This was a single-institution retrospective study of patients who underwent a first-time endoscopic endonasal approach (EEA) with NSF reconstruction. Participants Patients underwent an EEA to the skull base with NSF reconstruction and received postoperative MRI within 3 weeks of the operation. Main Outcome Measures MR exams were scored on the degree of contrast enhancement at first postoperative MRI. An enhancement score of 4 indicated ≥75% enhancement of the NSF. A score of 3 indicated enhancement ≥50% and <75% enhancement of the NSF. A score of 2 indicated ≥25% and <50% enhancement of the NSF. Complications (e.g., cerebrospinal fluid [CSF] leak, meningitis, empyema, cerebritis, brain abscess, flap necrosis, and flap migration) were retrieved from our institution's skull base database. Logistic regression was used to determine the effect of the MRI enhancement score on the odds of developing a complication. Results Out of 99 patients in the study, six had complications. Patients who underwent NSF reconstruction of skull base defects were found to have 19 times higher odds of complication ( p = 0.007) if they had had an NSF enhancement score of 2 on their postoperative MRI when compared with patients with complete or near complete NSF enhancement (score 4). Conclusion Quantifying NSF enhancement with an MRI may help surgeons better predict which of their patients are at an increased risk of complication.

Conventional Magnetic Resonance Imaging (MRI) and histopathology agreement for the diagnosis of intracranial meningioma at Dr. Soetomo General Hospital, Surabaya, January 2016–December 2021: a single center study

Link of Video Abstract: https://youtu.be/OG7qXwNHzHQ Background: Meningioma, a prevalent intracranial neoplasm, ranks among the most frequently encountered tumors within the cranial cavity. The utilization of Magnetic Resonance Imaging (MRI) in the diagnostic process of meningioma has proven to be highly valuable. This study aims to evaluate the Conventional-MRI and histopathology agreement for the diagnosis of intracranial meningioma at Dr. Soetomo General Hospital, Surabaya. Methods: This study presents a diagnostic test and retrospective case-control analysis to evaluate the precision of head MRI in diagnosing intracranial meningioma, as confirmed by histopathological examination. The research was conducted at Dr. Soetomo Surabaya General Hospital from January 2016 to December 2021. Sample size calculations were performed on a cohort of patients diagnosed with intracranial meningioma who underwent head magnetic resonance imaging (MRI) scans and histopathological examinations at the Radiology and Anatomical Pathology Installation of Dr. Soetomo General Hospital. Only patients who satisfied the predetermined inclusion and exclusion criteria were included in the study. Data were analyzed using SPSS version 25.0 for Windows. Results: At the time of diagnosis, it was observed that the average diameter of grade II/III meningioma was 6.6 ± 1.5 cm, which was found to be greater than the average diameter of grade I meningioma, measuring 4 ± 1.92 cm. The prevalence of grade I meningioma was higher in the skull base region higher in the skull base region, accounting for approximately 36% of cases. Conversely, grade II/III meningioma was found more frequently in the non-skull base area, constituting approximately 76% of cases. In our investigation, it was observed that there exists a higher occurrence of irregular border shape in grade II/III meningioma, accounting for approximately 75% of cases, as compared to grade I meningioma, which only accounts for 14.2% of cases. The presence of contrast enhancement in meningiomas can provide valuable insights into their histological grade. Grade II/III meningiomas exhibit a higher degree of contrast enhancement, which is observed to be heterogeneously distributed in approximately 75% of cases. Conclusion: This study highlights the potential of MRI as a valuable tool in assessing the grade of meningioma while emphasizing the importance of considering other diagnostic modalities and clinical factors to ensure accurate diagnosis and treatment decisions.

Comparison of image quality, contrast administration, and radiation doses in pediatric abdominal dual-layer detector dual-energy CT using propensity score matching analysis

PurposeTo compare the image quality, contrast administration, and radiation dose between single-energy CT (SECT) and dual-energy CT (DECT) in pediatric patients. MethodsFrom March to December 2021, children who underwent abdominal SECT or DECT were retrospectively included in this study. The DECT group received 10–30 % less contrast than the routine dose. CT images were obtained at hepatic venous phase using a routine reconstruction method (iDose4). DECT scans were additionally reconstructed with a virtual monoenergetic image (VMI) at 40 and 65 keV. Quantitative image evaluations compared the contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the liver, portal vein, and pancreas. Qualitative analysis assessed degree of contrast enhancement, lesion or organ conspicuity, image noise, artificiality, and overall image quality. ResultsAmong 318 patients, 112 (median age, 16 years; 56 in each group) were included after propensity score matching. Compared with the SECT group, DECT group with iDose4 demonstrated lower CNRs and SNRs, while VMI at 40 or 65 keV showed no significant difference. In qualitative analysis, iDose4 produced higher scores on artificiality, and VMI at 40 keV demonstrated superior contrast enhancement and lesion conspicuity in the DECT group. Overall image quality was higher with VMI 65 keV among the DECT patients, and there was no significant difference compared to SECT. The volume CT dose index (CTDIvol) did not differ significantly between the two groups (median, 2.8 mGy vs. 2.9 mGy; p = 0.802). The injected contrast volume was reduced by 10 % in the DECT group. ConclusionPediatric abdominal DECT with reduced contrast administration showed no significant differences in image quality and radiation dose compared to SECT.

T1 contrast versus fluid-attenuated inversion recovery contrast technique for evaluation of cerebral tuberculosis

Objectives: T2-weighted (T2W) fluid-attenuated inversion recovery (FLAIR), a traditional magnetic resonance imaging (MRI) technique, is regarded as one of the most effective methods for examining brain disorders. The identification of brain pathologies can be significantly aided by T2 FLAIR and T1 post-contrast imaging. However, lesion enhancement is occasionally inconspicuous on T1-weighted image. Hence, for the evaluation of brain disorders, a MRI approach known as FLAIR contrast would combine the benefits of T2W FLAIR with contrast-enhancement on a single picture. Material and Methods: After obtaining clearance from the Institution’s Ethics Committee, contrast-enhanced MRI (CE-MRI) brain of 20 patients was taken for the study. CE-MRI was performed using 1.5 Tesla Intera PHILIPS with intravenous administration of gadolinium at approximately 0.1 mL/kg/body at a rate of 10 mL/15 s. Results: This study showed a better appreciation of lesion conspicuity when compared to prior T1 contrast images. However, there was no significant difference in the number of lesions, lesion extension, and degree of contrast-enhancement on comparison with T1 contrast images. Conclusion: T1 FLAIR contrast shows a better appreciation of lesion conspicuity when compared to T1 contrast images. Post-contrast FLAIR imaging is a valuable adjunct to post-contrast T1W imaging and effectively delineates cerebral tubercular pathologies. However, T1 FLAIR cannot be used as a replacement for conventional T1 fat saturated post-contrast imaging.

Variations in the morphology of lagomorph confluence sinuum on contrast enhanced CT.

Knowledge of lagomorph confluence sinuum anatomy on contrast-enhanced CT may prevent the misdiagnoses of intracranial, extra-axial masses. The purpose of this retrospective, observational, descriptive study was to describe the characteristics of the confluence sinuum in rabbits on contrast-enhanced CT. Images of 24 rabbits who had pre- and postcontrast CT sequences of the skull were reviewed by an American College of Veterinary Radiology-certified veterinary radiologist and third-year radiology resident. Degree of contrast enhancement within the region of the confluence sinuum was graded based on consensus as no (0), mild (1), moderate (2), or marked (3) contrast enhancement. Hounsfield units (HU) of the confluence sinuum was measured in three different regions of interest, averaged for each patient, and divided into each group for comparison using one-way ANOVA analysis. Contrast enhancement was mild in 45.8% (11/24) rabbits, moderate in 33.3% (8/24), marked in 20.8% (5/24), and none in 0.0% (0/24). There were significant differences (P<0.05) between the average HU of the mild and marked group (P-value=0.0001) and moderate and marked groups (P-value=0.0010). Two rabbits with marked contrast enhancement were initially misdiagnosed with an intracranial, extra-axial mass along the parietal lobe based on contrast-enhanced CT. On necropsy, no gross or histopathological abnormalities were identified in the brain for these rabbits. In summary, contrast enhancement was identified in all rabbits (24/24) on contrast-enhanced CT imaging . This normal structure can be variable in size should not be mistaken for a pathological lesion in the absence of mass effect, secondary calvarial lysis, or hyperostosis.

Accuracy of apparent diffusion coefficient values for distinguishing between pineal germ cell tumour and pineoblastoma

To differentiate between pineal germ cell tumour and pineoblastoma using apparent diffusion coefficient (ADC) values due to their overlapping imaging findings on magnetic resonance imaging (MRI). This retrospective study was conducted on 33 patients with pineal germ cell tumours and eight patients with pineoblastoma who underwent pretreatment MRI. Twenty-seven patients (21 with pineal germ cell tumour and six with pineoblastoma) were included for ADC measurement. The minimum and mean ADC values of the tumours were measured, with normalized tumour to control ADC ratios generated. The MRI characteristics of the tumours were evaluated. The mean and minimum ADC values, normalized mean and minimum ADC ratios of pineal germ cell tumours were significantly higher than those of pineoblastomas (all p<0.005). A cut-off value of 0.92 for the normalized mean ADC ratio was used to distinguish between pineal germ cell tumour and pineoblastoma and achieved an area under the curve of 0.95, sensitivity of 90.5%, specificity of 83.3%, and accuracy of 92.6%. An equal degree of contrast enhancement to the adjacent venous sinus was the only MRI characteristic that suggested the diagnosis of pineal germ cell tumour. The ADC values could help differentiate between pineal germ cell tumour and pineoblastoma, specifically when conventional MRI findings are indeterminate.

Impaired intracranial venous outflow profiles are associated with poor outcome in stroke after reperfusion therapy: A hypoperfusion-matched intracranial venous scale

PurposeArterial blood flow provided prognostic information in acute ischemic stroke (AIS). However, part of the patients with favorable arterial blood flow still suffered from poor outcomes after reperfusion therapy. We aimed to verify the hypothesis that intracranial venous outflow profiles (both cortical and deep) within the hypoperfusion area were associated with clinical outcome in AIS patients who received reperfusion therapy. MethodWe performed a retrospective analysis of prospectively collected data from anterior circulation AIS patients. All patients underwent pretreatment CTP and received reperfusion therapy. We constructed a 5-point hypoperfusion-matched Intracranial Venous Scale (hypo-IVS) from the sum of the contrast enhancement degree (1, attenuated contrast enhancement; 0, complete contrast enhancement) of 4 typical veins (superficial middle cerebral vein, vein of Labbé, vein of Trolard, and internal cerebral vein) whose outflow territories had matched hypoperfusion. Logistic and ordinal regression were used to analyze the association between hypo-IVS and clinical outcome. ResultsA total of 751 patients were included. Higher Hypo-IVS was significantly associated with poor outcome (3-month mRS of >2; OR = 1.194; 95 % CI: 1.014–1.407; p = 0.033). The adjusted ORs for poor outcome and high 24-hour NIHSS were 1.172 (95 %CI: 1.035–1.328; p = 0.012) and 1.176 (95 %CI: 1.030–1.330; p = 0.010) in ordinal regression, respectively. Hypo-IVS > 2 was an independent risk factor of poor outcome (75.2 % vs 40.8 %; OR = 1.932; 95 %CI: 1.158–3.224; p = 0.012). ConclusionsIntracranial venous outflow profiles deliver prognostic information in AIS and the hypo-IVS is a helpful tool to predict clinical outcomes after reperfusion therapy.

Contrast-Enhanced Spectral Mammography in the Evaluation of Breast Microcalcifications: Controversies and Diagnostic Management

The aim of this study was to evaluate the diagnostic performance of contrast-enhanced spectral mammography (CESM) in predicting breast lesion malignancy due to microcalcifications compared to lesions that present with other radiological findings. Three hundred and twenty-one patients with 377 breast lesions that underwent CESM and histological assessment were included. All the lesions were scored using a 4-point qualitative scale according to the degree of contrast enhancement at the CESM examination. The histological results were considered the gold standard. In the first analysis, enhancement degree scores of 2 and 3 were considered predictive of malignity. The sensitivity (SE) and positive predictive value (PPV) were significative lower for patients with lesions with microcalcifications without other radiological findings (SE = 53.3% vs. 82.2%, p-value < 0.001 and PPV = 84.2% vs. 95.2%, p-value = 0.049, respectively). On the contrary, the specificity (SP) and negative predictive value (NPV) were significative higher among lesions with microcalcifications without other radiological findings (SP = 95.8% vs. 84.2%, p-value = 0.026 and NPV = 82.9% vs. 55.2%, p-value < 0.001, respectively). In a second analysis, degree scores of 1, 2, and 3 were considered predictive of malignity. The SE (80.0% vs. 96.8%, p-value < 0.001) and PPV (70.6% vs. 88.3%, p-value: 0.005) were significantly lower among lesions with microcalcifications without other radiological findings, while the SP (85.9% vs. 50.9%, p-value < 0.001) was higher. The enhancement of microcalcifications has low sensitivity in predicting malignancy. However, in certain controversial cases, the absence of CESM enhancement due to its high negative predictive value can help to reduce the number of biopsies for benign lesions.

Assessing the role of sodium fluorescein in peripheral nerve sheath tumors and mimicking lesions surgery: An update after 142 cases.

Peripheral nerve sheath tumors (PNST) include mainly schwannomas and neurofibromas. Surgical resection represents the mainstay of treatment but due to their pathogenesis, distinguishing between intact functional nerve and the fibers from whence the PNST arose may not always be easy to perform, constituting the most relevant risk factor in determining a worsening in neurological condition. The introduction of intraoperative tools to better visualize these tumors could help achieve a gross-total resection. In this study, we analyzed the effect of sodium fluorescein (SF) on the visualization and resection of a large cohort of PNST. Between September 2018 and December 2021, 142 consecutive patients harboring a suspected PNST underwent fluorescein-guided surgery at the Department of Neurosurgery of the Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy. All patients presented with a different degree of contrast enhancement at preoperative MRI. SF was intravenously injected after intubation at 1 mg/kg. Intraoperative fluorescein characteristics and postoperative neurological and radiological outcomes were collected, analyzed, and retrospectively compared with a historical series. 142 patients were included (42 syndromic and 100 sporadic); schwannoma was the predominant histology, followed by neurofibroma (17 neurofibroma e 12 plexiform neurofibroma) and MPNST. Bright fluorescence was present in all cases of schwannomas and neurofibromas, although with a less homogeneous pattern, whereas it was significantly less evident for malignant PNST; perineurioma and hybrid nerve sheath tumors were characterized by a faint fluorescence enhancement. The surgical resection rate in the general population and even among the subgroups was about 66.7%; from the comparative analysis, we found a consistently higher rate of complete tumor removal in plexiform neurofibromas, 66% in the "fluorescent" group vs 44% in the "historical" group (p-value < 0.05). The rate of complications and mean surgical time were superimposable among the two populations. SF is a valuable method for safe fluorescence-guided PNST and mimicking lesions resection. Our data showed a positive effect of fluorescein-guided surgery in increasing the rate of surgical resection of plexiform neurofibromas, suggesting a possible role in improving the functional and oncological outcome of these lesions.

"Star of Bethlehem sign" in the analysis of the evolution of brain lesions during and after treatment for neuroparacoccidioidomycosis.

To describe the clinical and radiological evolution of lesions during and after treatment in patients diagnosed with neuroparacoccidioidomycosis (NPCM). This was a retrospective study of the medical records, computed tomography scans, and magnetic resonance imaging (MRI) scans of patients with NPCM treated between September 2013 and January 2022. Of 36 cases of NPCM, eight were included in the study. One patient presented only with pachymeningeal and skull involvement, and seven presented with pseudotumors in the brain. Collectively, the eight patients presented with 52 lesions, of which 46 (88.5%) were supratentorial. There were 32 lesions with a diameter ≤ 1.2 cm, of which 27 (84.4%) disappeared during the treatment. In three cases, there were lesions > 1.2 cm that showed a characteristic pattern of evolution on MRI: an eccentric gadolinium contrast-enhanced nodule, with a subsequent decreased in the size and degree of contrast enhancement of the lesions. In NPCM, supratentorial lesions seem to predominate. Lesions ≤ 1.2 cm tend to disappear completely during treatment. Lesions > 1.2 cm tend to present with a similar pattern, designated the "Star of Bethlehem sign", throughout treatment.

The role of sodium fluorescein in pediatric supratentorial intra-axial tumor resection: new insights from a monocentric series of 33 consecutive patients.

Surgical resection represents the mainstay of treatment, in pediatric central nervous system (CNS) tumors, and aggressive resection correlates with prognosis for several histotypes. Sodium fluorescein (SF), a green, water-soluble dye, is used as neurosurgical fluorescent tracer thanks to its property to accumulate in cerebral regions of blood-brain barrier disruption, acting as a valid tool to improve the extent of resection in tumors enhancing at preoperative MRI. Brain neoplasms represent a heterogeneous group of tumors in the pediatric age, constituting the most common solid cancers; they typically show a varying degree of contrast enhancement on MRI. In March 2016, the authors started a prospective, observational trial to evaluate intraoperative fluorescence's characteristics of CNS tumors, the percentage of extent of resection, thanks to fluorescein aid, and side effects related to fluorescein administration. This report is based on a retrospective analysis of a group of 33 consecutive pediatric patients harboring a supratentorial lesion. In 17 of 33 (51.5%) procedures, fluorescence was reported as intense; in 14 of 33 (42.4%), moderate; and in 2 of 33 (6.1%), slight. Intraoperative fluorescence corresponds to preoperative-MRI-documented contrast enhancement. In 28 of 33 (84.8%) surgical procedures, SF was considered useful; in 2 of 33 (6.1%), partial useful; and in 3 of 33 (9.1%), not essential because the tumor was already recognizable. No adverse effect to SF administration was registered. Fluorescein-guided surgery with a dedicated filter on the microscope is a safe and effective technique to improve visualization and resection of different pediatric brain tumors.

PEDT-5 PREOPERATIVE MAGNETIC RESONANCE IMAGING AND INTRAOPERATIVE BLOOD LOSS IN CHILDHOOD POSTERIOR FOSSA TUMORS

Abstract Background and Purpose For removal of childhood posterior fossa tumors, it is important to control bleeding while internally decompressing the tumor. Evaluation of tumor vascularity by preoperative magnetic resonance imaging (MRI) is thought to be effective in predicting and controlling blood loss. In this study, we evaluated the relationship between imaging features, mainly susceptibility-weighted imaging (SWI), and the amount of intraoperative blood loss. Methods Among childhood posterior fossa tumors operated on by the same surgeon between January 2016 and March 2022, 9 cases in which preoperative MRI data could be analyzed and total or subtotal resection was achieved were included. The SWI: intratumoral susceptibility signals (ITSS) grade, an index of tumor vascularity, was used to evaluate the association between the degree of vascularity (ITSS: 0-2 vs. ITSS: 3) and multiple factors, including intraoperative blood loss, in a univariate analysis. In addition, the intraoperative blood loss was analyzed by multivariate analysis. Results There were 3 males and 6 females with a median age of 6 years (5-11). Seven medulloblastomas, one atypical teratoid/rhabdoid tumor, and one ependymoma were included. Univariate analysis showed that patients with higher vascularity (ITSS: 3) had significantly higher intraoperative blood loss (p=0.016) and larger tumor volume (p=0.032). In multivariate analysis with age, degree of contrast enhancement, degree of vascularity, tumor volume, and degree of tumor resection as independent variables, the degree of vascularity was not significantly associated with intraoperative blood loss (p=0.477), but only with tumor volume (p=0.036). Conclusion Although the degree of tumor vascularity may be related to intraoperative blood loss, there was a strong correlation between the degree of vascularity and tumor volume, and multivariate analysis of intraoperative blood loss showed that only tumor volume was a significant factor. Higher tumor vascularity was associated with larger tumor volume, which may result in increased intraoperative bleeding.

Neuroimaging in Pediatric Patients with Juvenile Xanthogranuloma of the CNS.

Juvenile xanthogranuloma is a rare clonal, myeloid, neoplastic disorder. Typically, juvenile xanthogranuloma is a self-limited disorder of infancy, often presenting as a solitary red-brown or yellow skin papule/nodule. A small subset of patients present with extracutaneous, systemic juvenile xanthogranuloma, which may include the CNS. The goal of this retrospective study was to evaluate and categorize the neuroimaging findings in a representative cohort of pediatric patients with CNS juvenile xanthogranuloma. The brain and/or spine MR imaging data of 14 pediatric patients with pathology-proven juvenile xanthogranuloma were categorized and evaluated for the location; the signal intensity of xanthogranulomas on T1WI, T2WI, DWI, and a matching ADC map for the pattern and degree of contrast enhancement; and the presence of perilesional edema, cysts, or necrosis. Fourteen pediatric patients (8 girls, 6 boys; mean age, 84 months) were included in the study. Patients presented with a wide variety of different symptoms, including headache, seizure, ataxia, strabismus, hearing loss, facial paresis, and diabetes insipidus. Juvenile xanthogranuloma lesions were identified in a number of different sites, including supra- and infratentorial as well as intracranial and spinal leptomeningeal. Five patients were categorized into the neuroradiologic pattern unifocal CNS juvenile xanthogranuloma; 8, into multifocal CNS juvenile xanthogranuloma; and 1, into multifocal CNS juvenile xanthogranuloma with intracranial and spinal leptomeningeal disease. In most cases, xanthogranulomas were small-to-medium intra-axial masses with isointense signal on T1WI (compared with cortical GM), iso- or hyperintense signal on T2WI, had restricted diffusion and perilesional edema. Almost all xanthogranulomas showed avid contrast enhancement. However, we also identified less common patterns with large lesions, nonenhancing lesions, or leptomeningeal disease. Four cases had an additional CT available. On CT, all xanthogranulomas were homogeneously hyperdense (solid component) without evident calcifications. CNS juvenile xanthogranuloma may demonstrate heterogeneous neuroimaging appearances potentially mimicking other diseases, such as primary brain neoplasms, metastatic disease, lymphoma and leukemia, other histiocytic disorders, infections, or granulomatous diseases.

Effects of Norepinephrine on Renal Cortical and Medullary Blood Flow in Atherosclerotic Rabbits.

The aim of this study was to explore the effect of norepinephrine (NE) on renal cortical and medullary blood flow in atherosclerotic rabbits without renal artery stenosis. Atherosclerosis was induced in 21 New Zealand white rabbits by feeding them a cholesterol-rich diet for 16 weeks. Thirteen healthy New Zealand white rabbits were randomly selected as controls. After atherosclerosis induction, standard ultrasonography was performed to confirm that there was no plaque or accelerated flow at the origin of the renal artery. Contrast-enhanced ultrasound (CEUS) was performed at baseline and during intravenous injection of NE. The degree of contrast enhancement of renal cortex and medulla after the injection of contrast agents was quantified by calculating the enhanced intensity. The serum nitric oxide (NO) level in atherosclerotic rabbits was higher than that in healthy rabbits (299.6±152 vs. 136.5±49.5, P<0.001). The infusion of NE induced a significant increase in the systolic blood pressure (112±14 mmHg vs. 84±9 mmHg, P=0.016) and a significant decrease in the enhanced intensity in renal cortex (17.78±2.07 dB vs. 21.19±2.03 dB, P<0.001) and renal medulla (14.87±1.82 dB vs. 17.14±1.89 dB, P<0.001) during CEUS. However, the enhanced intensity in the cortex and medulla of healthy rabbits after NE infusion showed no significant difference from that at baseline. NE may reduce renal cortical and medullary blood flow in atherosclerotic rabbits without renal artery stenosis, partly by reducing the serum NO level.

The role of methylation profiling in histologically diagnosed neurocytoma: a case series

PurposeTo highlight the clinical, neuroradiographic, neuropathologic, and molecular features of histologically identified neurocytoma in a pediatric cohort and highlight the evolving use methylation profiling in providing diagnostic clarity in difficult to diagnosis pediatric brain tumors.MethodsFive consecutive children (ages 9–13, 2 girls 3 boys) were histologically diagnosed with neurocytoma at Rady Children’s Hospital San Diego from 2012 to 2018. Clinical and molecular features were analyzed with regards to treatment course and outcome.ResultsPresenting symptoms included seizures (n = 2), syncope (n = 1), headache (n = 2), visual disturbances (n = 2) and emesis (n = 2). Tumor location included intraventricular (n = 2), intraventricular with parenchymal spread (n = 1), and extraventricular (n = 2). Magnetic resonance imaging demonstrated reduced diffusivity (2/5), signal abnormality on susceptibility-weighted sequences (3/5), and varying degrees of contrast enhancement (4/5). All patients underwent surgical resection alone. Recurrence occurred in four children that were treated with surgery (4/4), adjuvant radiation (2/4), and chemoradiation (1/4). Neuropathologic features included positivity for GFAP (4/5), synaptophysin (4/5), NSE (2/2), NeuN (4/4), and variable Ki-67 (< 1% to 15%). Next generation sequencing (3/5) and microarray (3/5) collectively were abnormal in four of five tumors. Methylation profiling was successfully performed on four of five samples which led to modification of diagnosis in two patients and the others were either unclassifiable or confirmatory with the histologic diagnosis. Mean time to follow up was 77 months (range 44–112 months). Mean progression free survival and overall survival were 24 months (range 6 to 52 months) and 100% respectively.ConclusionNeurocytomas are a rare clinical entity that warrants further investigation into molecular and pathologic prognosticating features. Methylation profiling may aid in differentiation of neurocytoma from other difficult to diagnose tumors who share similar histologic features.