Intracranial extra-axial chondromas: clues to computed tomography and magnetic resonance imaging diagnosis.

AIM: We aimed to describe the computed tomography (CT) and magnetic resonance (MR) imaging findings of intracranial extra-axial chondroma. MATERIAL AND METHODS: We retrospectively evaluated the imaging findings of CT and MR examinations of six patients (three men and three women, aged 21-66 years) with histopathological diagnoses of intracranial extra-axial chondroma. RESULTS: Four tumors were located in the frontal region and two in the cavernous sinus. All the tumors showed low signals on diffusion-weighted images and high signals on apparent diffusion coefficient maps without restricted diffusion. There was no perifocal edema in all the tumors. Cavernous sinus chondromas were associated with bone erosion and anterior displacement of the internal carotid arteries, but without calcification. Calcification was present in all frontal chondromas. All the tumors revealed low signals on T1-weighted MR images. Frontal chondromas revealed mixed signals, but cavernous sinus chondromas were brightly hyperintense on T2-weighted MR images. No enhancement was detected in the two chondromas. An intense homogeneous enhancement was detected in a cavernous sinus chondroma. CONCLUSION: The imaging appearances of frontal extra-axial chondromas and cavernous sinus chondromas may have different imaging appearances. Although there is a wide range of imaging findings, the absence of restricted diffusion, perifocal edema, enhancement, and presence of low signals on T1-weighted MR images in a well-circumscribed calcified extra-axial mass should suggest an intracranial chondroma.

Ectopic Pituitary Neuroendocrine Tumors/Adenomas Around the Sella Turcica.

Functional or non-secretory ectopic pituitary neuroendocrine tumors (PitNET) can form around the sella turcica during the development of the adenohypophysis by differentiating and detaching from the pharyngeal roof. These tumors usually appear in the sphenoid sinus, clivus, cavernous sinus, infundibulum, and suprasellar cistern. Ectopic PitNETs typically display the characteristic magnetic resonance imaging findings of pituitary adenomas. However, preoperative diagnosis of PitNETs is usually challenging because of the variety of clinical and imaging presentations, locations, and sizes. Ectopic suprasellar PitNETs resemble mass lesions in the pituitary stalk. Ectopic cavernous sinus of PitNETs are typically microadenomas in the medial wall. Ectopic sphenoclival tumors are characterized by more aggressive tumor activity than the other ectopic PitNETs. Although ectopic PitNETs are exceedingly rare, they should be considered as a differential diagnosis for masses around the sella turcica. Treatment of the disease should be individualized and may include medical care, surgical resection, gamma-knife radiosurgery, and radiotherapy.

Isolated infantile myofibroma of the calvarium: Report of a case with a literature review.

OBJECTIVE: Infantile myofibromatosis is a rare entity of childhood characterized by benign myofibroblastic tumors in the soft tissues, the bones, and occasionally the viscera. Solitary skeletal lesions are relatively uncommon. Calvarial involvement should be distinguished from more aggressive tumors for appropriate treatment. METHODS: We reviewed solitary infantile myofibroma of the calvarium and discussed the relevant computed tomography and magnetic resonance imaging findings along with differential diagnosis. A case study of the frontal bone in a 5-month-old girl was also presented. RESULTS: Fourteen cases were reviewed, including the current case. Of the 13 cases with known sex, eight were male and five female. The mean age was 3.03 with an age range of 0.41-9 years. Nine of the 14 tumors were in the frontal bone. The lesions were intradiploic with tabula interna and/or externa of the calvaria involvement. The mean largest diameter was 22.3 mm. Upon computed tomography, all the lesions were expansile and lytic, and hypoattenuated, isoattenuated or occasionally hyperatenuated. Calcification was not seen. On magnetic resonance imaging, most neoplasms were hypointense on T1-weighted and T2-weighted images. Neoplasms showed hypointense signal on diffusion-weighted imaging and hyperintense on apparent diffusion coefficient, without restricted diffusion in three cases. All lesions were intensely enhanced after gadolinium administration. Treatment was total surgical resection and recurrence was not observed during follow-up. CONCLUSIONS: Infantile myofibromas are rare, typically intradiploic expansile lytic lesions with tabula interna and/or externa involvement. Distinctive imaging features include the presence of hipointense signals on T2-weighted magnetic resonance images without restricted diffusion on diffusion-weighted imaging. A slow-growing, firm, painless, and nontender mass with supportive imaging findings should raise suspicion of the disease.

Diffuse Leptomeningeal Glioneuronal Tumors: A Case Series of Five Patients with Parenchymal Forms and an Analysis of the Diagnostic Challenges, Treatment Options and Outcomes.

BACKGROUND: Diffuse leptomeningeal glioneuronal tumors (DL-GNT) are rare glioneuronal neoplasms with oligodendroglioma-like cells. These tumors can present as a dominant intracranial mass or as a solitary spinal cord mass without leptomeningeal involvement. In this study, we aimed to determine the magnetic resonance imaging and histopathological features, treatment modalities, and clinical outcomes of the parenchymal forms of DL-GNTs. METHODS: This is a retrospective three-center case series study of 5 patients with a confirmed parenchymal form of DLGTs, out of which 4 patients were adults. Brain and spinal cord MR imaging were performed in all patients at either 1.5 or 3T. The patients' age ranged from 5 years to 50 years with a mean age of 27.6 years at presentation. RESULTS: Four of the tumors were located in the frontal lobe, and one in the tectum. They were usually solid-cystic enhancing tumors as the other mixed neuronal-glial tumors. All of the tumors had an extension to the superficial surface of a cerebral hemisphere. One had systemic bone metastases. The clinical signs and symptoms of the parenchymal form varied based on the location of the mass, in contrast to the leptomeningeal form associated with hydrocephalus. In one case, the tumor's initial grade was defined as intermediate. The initial histopathology of the two cases was low-grade and no upgrade occurred in the follow-up period. In two cases, although the tumors were low grade initially, they progressed to an anaplastic form in the follow-up period. CONCLUSION: The parenchymal form of DL-GNTs is common in adults. Extension to the superficial surface of a cerebral hemisphere is a distinctive imaging feature. Systemic osseous metastasis may occur. Due to the presence of common histopathological features, including the biphasic composition of glial and neuronal cell elements and oligodendroglioma-like cells, a proposed classification approach might be more beneficial for the histopathological and imaging description, and management of the glioneuronal tumors with oligodendroglioma-like features.

Encephalomyelitis associated with Covid-19 infection: case report.

We describe a COVID-19 patient who presented with persistent headache and anosmia that was related to viral encephalomyelitis with acute lesions on MRI in both the brain and upper cervical cord.

Extensive widening of Virchow-Robin spaces in the frontal lobe: two case reports and systematic review of the literature.

AIM: To report our experience on giant tumefactive Virchow-Robin spaces (GTVRS) in the frontal lobe and perform a systematic review of previous reports on GTVRS. MATERIALS AND METHODS: This is a retrospective single-center study reporting the clinical manifestations, magnetic resonance (MR) imaging appearance, differential diagnosis, and management of two patients diagnosed with frontal lobe GTVRS at Bahcesehir University School of Medicine Goztepe Hospital in the past 5 years. A systematic literature search was performed in the PubMed and Google Scholar databases, with case selection criteria including Virchow-Robin spaces (VRS) size greater than 1.5 cm, frontal lobe localization, and the presence of MR imaging. The search strategy included only English language keywords. The systematic review was searched between database inception and May 6, 2022. RESULTS: A total of 18 cases were included in the study. Of the 15 cases with known sex, nine were female and six male. The median age was 29.8 with an age range of 4-57. Eleven of the 18 lesions were in the right frontal lobe. The lesions were multilocular in 15 cases and unilocular in three cases. All lesions had signal intensity as cerebrospinal fluid, showed no perifocal edema, and did not enhance. A hyperintensity was noted around the 14 lesions on the FLAIR sequence. Ten lesions showed cortical thinning adjacent to the lesion. No abnormality was detected on DWI, SWI, and MRS. Follow-up imaging was available in ten patients without any interval change. Unnecessary surgical interventions were noted in three cases. CONCLUSIONS: The results of reported cases and the literature review emphasize the role of MR imaging in the diagnosis of frontal lobe GTVRS. Beyond diagnostic consideration, GTVRS may have prognostic value and often indicate a "don't touch lesion" albeit requiring further consideration on a case-to-case basis. Familiarity with this entity improves diagnostic accuracy and, prevents accidental diagnosis of any neoplasm or other diseases.

Malignant Progression of a Superior Cerebellar Tentorium Solitary Fibrous Tumor in the Pineal Region with Intracranial Metastases: A Case Report and a Literature Review.

BACKGROUND: Pineal region solitary fibrous tumors (SFT) incorporate a histologic spectrum of rarely metastasizing mesenchymal neoplasms that include tumors formerly classified as hemangiopericytoma. CASE REPORT: Here, we describe a rare case of SFT of the pineal region in a 25-year-old man with a literature review. After the first surgery, the tumor reappeared as a local low-grade recurrence, followed by metastasis to the right parietal lobe, and then hyperacute intraparenchymal hematoma at the metastatic site, and later presentation of widespread intracranial intra-axial and extra-axial metastases during the follow-up period. Systemic metastases were not detected. The histopathological evaluation of the resected tissues confirmed the malignant progression of the tumor. CONCLUSION: The diagnosis of SFT of the pineal region through clinical and imaging features can be considerably challenging. Large size, intratumoral cystic areas, and intense contrast enhancement are the main conventional imaging characteristics of the tumor. Surgery is the first preferential treatment. All recurrent or metastatic cases were grade II or grade III tumors. Adjuvant radiotherapy should be added to surgical treatment in high-grade tumors. Gamma knife radiosurgery is a treatment option for intracranial metastases.

Magnetic Resonance Imaging of Unusual Neoplasms Related to Foramen of Luschka: A Review for Differential Diagnosis.

There are many types of neoplasms in or around the foramen of Luschka (FL), and definitive diagnosis in some cases requires knowledge of imaging findings. The uncommon and challenging neoplasms with FL involvement considered in this study are exophytic brainstem glioma, primary glioblastoma of the cerebellopontine angle (CPA), primary anaplastic ependymoma of the CPA, choroid plexus papilloma of the FL, solitary FL choroid plexus metastasis, extraskeletal myxoid chondrosarcoma of the jugular foramen, paraganglioma of the jugular foramen, exostosis of the jugular foramen, psammomatous meningioma in the lateral cerebellar medullary cistern, epidermoid tumor of the fourth ventricle, and a hypoglossal schwannoma. These neoplasms may have overlapping clinical and imaging features, but some have relatively distinct imaging features. Knowledge of the key clinical and magnetic resonance imaging features of these unusual lesions with FL involvement is important for radiologists to improve diagnostic ability and to assist the referring physician in the appropriate management of the patient.

Isolated Pituitary Metastasis of Renal Cell Carcinoma: A Case Report and Systematic Review of the Literature.

BACKGROUND: Isolated pituitary gland metastasis is an extremely rare event in renal cell carcinoma. We present a unique case of isolated pituitary metastasis of renal cell carcinoma and a systematic review of literature on it. CASE REPORT: In this case, an abdominal ultrasound in an asymptomatic 51-year-old female patient showed a mass in her left kidney. Radical nephrectomy was performed and the tumor was diagnosed as a stage 1 clear cell carcinoma. Throughout the 3 months of the follow-up period, the patient started complaining of visual disturbances and headaches. A pituitary mass was found on brain magnetic resonance imaging and was suspected to be a macroadenoma. Surgical resection of the tumor was performed and the final pathological diagnosis was made as a pituitary metastasis of the renal cell carcinoma. After surgery, radiotherapy with sunitinib, a receptor tyrosine inhibitor, was performed. CONCLUSION: The clinical symptoms are usually related to the mass effect of the tumor and anterior pituitary involvement. Most of the cases mimic pituitary macroadenoma on MRI. The most preferred treatment combination is surgery and radiotherapy. We recommend adding sunitinib to this combination. This illustrative case and those found in a systematic review of the literature highlight the importance of histopathologic diagnosis and appropriate management since isolated pituitary metastasis is challenging to preoperative diagnosis.

Magnetic resonance imaging criteria for prediction of isocitrate dehydrogenase (IDH) mutation status in patients with grade II-III astrocytoma and oligodendroglioma.

BACKGROUND: IDH mutation status is an important prognostic marker for glial tumors, which is detected immunohistochemically after surgery. Since this method is invasive, easy and noninvasive magnetic resonance imaging (MRI) methods have recently been used in predicting the IDH mutation status. However, there is currently no standard MRI technique to predict IDH mutation. We analyzed the value of conventional MRI to predict IDH mutation and its effect on survival among grade II-III astrocytoma and oligodendroglioma patients. MATERIAL AND METHODS: We included WHO grade II-III astrocytoma and oligodendroglioma patients who underwent surgery at Bahcesehir University Goztepe Medical Park Hospital. All patients were analyzed according to their immunohistochemical IDH mutation status. Preoperative conventional MRI studies with respect to their location, diffusion restriction, contrast enhancement, calcification and hemorrhage on susceptibility-weighted image (SWI) or T2*- weighted imaging (T2*WI), and T2 -FLAIR mismatch properties were retrospectively assessed by a neuroradiologist. The relation between MRI characteristics and IDH mutation was analyzed using a chi-square test. The sensitivity and specificity of radiological IDH mutation were determined by ROC analysis. The impact of IDH mutation on survival was also analyzed by Kaplan-Meier tests. RESULTS: IDH mutation was found to be positive in 82.5% of tumors histopathologically and 54.4% radiologically. The sensitivity and specificity were 63.8% and 90%, respectively (Area under the curve/AUC = 0.369, p = 0.08). IDH wild gliomas were predominantly diffusion-restricted tumors. IDH mutant tumors were less likely to have contrast enhancement and had lower grades compared to the IDH wild tumors. The median survival time could not be reached and the overall survival was not related to any tumor characteristics or IDH mutation. CONCLUSIONS: Conventional MRI predicts IDH-mutation status in Grade II-III astrocytoma and oligodendroglioma. Contrast-enhancement and restricted diffusion were strongly associated with grade III astrocytoma and oligodendroglioma, IDH-wild type. Location, T2-FLAIR mismatch, and SWI did not contribute to making a decision on the IDH mutation status. There was no significant difference between the survival times of patients and their IDH status.

Abdominal Variant of Lemierre's Syndrome in a Patient with Pancreatic Adenocarcinoma.

Lemierre's syndrome is an illness characterized by internal jugular vein thrombophlebitis related to infectious agents, primarily Fusobacterium necrophorum. These bacteria, residing in both the oropharynx and the gastrointestinal tract, may lead to pylephlebitis, a serious condition that could result in the development of hepatic abscesses. This manifestation of the disease is regarded as the abdominal variant of Lemierre's syndrome. Patients with gastrointestinal malignancies, especially those who undergo surgeries, are susceptible to the abdominal variant of Lemierre's syndrome. Timely diagnosis is required to avoid the life-threatening complications of the abdominal variant of Lemierre's syndrome. Diffusion-weighted magnetic resonance imaging (MRI) might be very useful in differentiating this disease from liver metastasis in patients with malignancies. Radiologists and clinicians need to be aware of this challenging condition to prevent misdiagnosis, since prompt treatment is often lifesaving.

Allogeneic hematopoietic stem cell transplantation in patients with childhood cerebral adrenoleukodystrophy: A single-center experience "Better prognosis in earlier stage".

BACKGROUND: ALD is a rare X-linked peroxisomal metabolic disorder with many distinct phenotypes of disease that emerge on a wide scale from adrenal insufficiency to fatal cALD which progresses to a vegetative state within a few years. Currently, HSCT is the only treatment method known to stabilize disease progression in patients with cALD. In this study, we aim to report our HSCT experience in patients with cALD and the factors that determine the success of HSCT, as a single-center experience. METHODS: The study cohort involves 23 boys with cALD and three patients with ALD trait and new-onset abnormal behavior who underwent allogeneic HSCT between January 2012 and September 2019 in our transplantation center. Loes scoring, NFS, scale and MFD were performed for evaluating the severity of the cerebral disease. The study cohort was divided into two groups according to baseline NFS and Loes score: early-stage (NFS ≤ 1 and Loes score <9) and advanced stage (NFS > 1 or Loes score ≥9). RESULTS: The pretransplant stage of disease impacted both OS and MFD-free survival. The estimated OS and MFD-free survival at 3 years in patients with advanced disease were 46.1% (95% CI 19.0-73.2) and 23.1% (95% CI 0.2-46.0), respectively, and all patients with the early disease were alive (p: .004) and MFD-free (p < .001) at 3 years. CONCLUSION: This study demonstrated that early HSCT is vital in patients with cALD. The early-stage disease had a significant survival advantage and free from disease progression after HSCT.