Pituitary adenoma associated with xanthogranuloma.

Xanthogranuloma (XG) of the sellar region is a non-neoplastic inflammatory lesion characterized histologically by recent and remote hemorrhage, necrotic debris, fibrosis, chronic inflammation, and cholesterol clefts with associated foreign-body giant cells. The inflammatory lesion was recognized by the World Health Organization in 2000. XG of the sellar region is rare. Cases of pituitary adenoma (PA) with an associated XG (PA/XG) are extremely rare, with a total of 16 cases in the literature. PA/XG lacks specific clinical and radiologic signs, making pre-operative diagnosis challenging. Herein, we report a case of PA/XG, describe the radiologic and pathologic findings, and discuss the role of so-called silent or "subclinical pituitary apoplexy" in the possible histogenesis of PA/XGs.

Qualitative and quantitative methods in post-chemoradiation PET for head and neck cancer.

OBJECTIVE: The aim of this study was to determine whether quantitative methods could aid in the evaluation of post-treatment head and neck scans, particularly taking human papillomavirus status into account. METHODS: Clinical readings of positron emission tomography/computed tomography scans as well as standardized uptake value (SUV)max (and other metrics) of nodes visible on PET conducted on a total of 172 patients with head and neck squamous cell cancer were examined. Locoregional recurrence at 2 years was assessed. In total 88 of these patients had close enough follow-up to determine whether individual nodes were positive or negative, and 233 nodes on these patients were compared to surgical pathology notes or follow-up (if no path was available). RESULTS: General negative predictive value (NPV) of complete response was 93% and an equivocal response was 89%; focusing on nodal recurrence, NPV was found to be 97% and positive predictive value (PPV) 46% if equivocal reads were treated as negative and NPV 98% and PPV 16% if equivocal reads were treated as positive. Using SUVmax of the hottest node with a cutoff of 3.4 gave NPV 97% and PPV 26%; a direct re-read (using 2 observers) gave NPV 98% and PPV 32% if equivocal reads were treated as negative, and NPV 99% and PPV 18% if equivocal reads were treated as positive. Using other first-order radiomics data such as SD and skewness did not improve this. CONCLUSIONS: Quantitative data such as SUVmax does not show additional value over qualitative evaluation of response to chemoradiation in head and neck tumors.

Postoperative seizures following endoscopic third ventriculostomy and choroid plexus cauterization: a case series.

OBJECTIVE: In this study, the authors sought to investigate variables associated with postoperative seizures following endoscopic third ventriculostomy and choroid plexus cauterization (ETV/CPC) for treatment of pediatric hydrocephalus. METHODS: A retrospective analysis of 37 patients who underwent ETV/CPC for treatment of hydrocephalus at an academic medical center from September 2016 to March 2021 was conducted. Demographics, etiology of hydrocephalus, operative details, electroencephalography (EEG) data, MRI findings, need for subsequent procedures, perioperative laboratory tests, medical history, and presence of clinical postoperative seizures were collected. Postoperative seizures were defined as clinical seizures within 24 hours of surgery. Eighteen patients received levetiracetam intraoperatively as well as over the next 7 days postoperatively for seizure prophylaxis. RESULTS: Of 37 included patients, 9 (24%) developed clinical seizures within 24 hours after surgery, 5 of whom subsequently had electroclinical seizures captured on video-EEG. The clinical seizures in 4 of those 5 patients (80%) may have been associated with the hemisphere of the brain through which the endoscope was introduced. The median corrected age of the cohort was 3.4 months. The median corrected age of patients who did not develop postoperative seizures was 2.3 months compared with 0.7 months for patients who did develop postoperative seizures (p > 0.99). Postoperative seizures occurred in 43% (3/7) of prenatally repaired myelomeningocele patients versus 29% (2/7) of postnatally repaired myelomeningocele patients. Of the 18 patients who received prophylactic levetiracetam, none (0%) developed postoperative seizures compared with 9 of the 19 patients (47%) who did not receive prophylactic levetiracetam (p = 0.014). CONCLUSIONS: Postoperative seizures were recorded in 24% of the pediatric patients who underwent ETV/CPC for hydrocephalus, which is higher than previously reported rates in the literature of 5%. Since 80% of the postoperative electrographic seizures may have been associated with the hemisphere through which the endoscope was introduced, the surgical entry site may contribute to postoperative seizure development. In patients who received prophylactic perioperative levetiracetam, the postoperative seizure incidence dropped to 0% compared with 47% in those who did not receive prophylactic perioperative levetiracetam. This finding indicates that the use of prophylactic perioperative levetiracetam may be efficacious in the prevention of clinical seizures in this patient population.

Detectable size of melanoma metastases to brain on PET/CT.

OBJECTIVE: We aimed to determine at what size melanoma metastases become detectable by PET/CT. METHODS: We reviewed a total of 293 whole-body PET/CT studies performed on 212 patients for staging of melanoma where there was an MRI within a month of the PET/CT. MR and PET/CT were reviewed independently by separate readers. RESULTS: PET/CT revealed an overall incidental true-positive rate of 1% on a per-patient basis, consistent with other studies, with 'hot' lesions (more avid than brain parenchyma) visible at smaller sizes than 'cold' lesions. CONCLUSIONS: PET/CT can detect metastatic melanoma lesions over about 2 cm in size, with hot lesions generally visible at smaller sizes.

CNS Vasculitis-An Overview of This Multiple Sclerosis Mimic: Clinical and MRI Implications.

This article discusses central nervous system vasculitis, a clinical and MRI mimic of multiple sclerosis (MS). There is a paucity of discussion of vasculitis in the radiology literature, and many MS neurologists believe that vasculitis is underdiagnosed. Therefore, the authors hope that the readers will find this paper increases their knowledge about CNS vasculitis and improves their ability to differentiate MS from vasculitis.

Complete remission with ibrutinib after allogeneic stem cell transplant for central nervous system relapse of mantle cell lymphoma: A case report and literature review.

Central nervous system (CNS)-relapsed mantle cell lymphoma (MCL) is a rare, aggressive non-Hodgkin lymphoma without a standard treatment. Ibrutinib has shown promising results for inducing remission in other non-Hodgkin lymphomas and may be considered as successful treatment for CNS-relapsed MCL in the future as well.

Subsequent experience in hybrid PET-MRI for evaluation of refractory focal onset epilepsy.

PURPOSE: Epilepsy surgery is the most successful method of treating medically unresponsive epilepsy, but carries a risk of morbidity. PET/MR is an emerging technique that increases detection of focal lesions whose resection may result in symptom remission. METHODS: Retrospective review of 74 focal epilepsy patients over a period of 3 years who had a PET/MR was performed following IRB permission and informed consent. 27 patients underwent surgery or RNS (responsive neurostimulator) placement. RESULTS: Hybrid PET-MR identified new anatomic or functional lesions in 10 patients not identified with standalone 3 T MR. Of the 27 patients who underwent focal surgery (19) or RNS placement (8), 24 showed improvement (Engel's I-III), 2 did not (Engel's IV), and one had an RNS explanted due to infection. MR and PET were read by 2 separate neuroradiologists and nuclear medicine physicians, respectively. Modalities were evaluated in terms of ability to detect the correct lobe and side for a focal lesion whose resection improved symptoms. Prior standalone MR exhibited 71-77% sensitivity and 0% specificity (as there were only 2 nonresponders), MR associated with PET/MR had 68-71% sensitivity and 0-50% specificity (depending on whether a lesion was seen on one of the nonresponders), and PET had 68-71% sensitivity and 25-33% specificity. Using either PET or MR to identify a focal lesion, PET/MR had sensitivity of 78-82% and specificity 0-50%. CONCLUSIONS: PET-MR provides additional sensitivity when used as two combined modalities for detecting possible epileptic foci.

Initial experience in hybrid PET-MRI for evaluation of refractory focal onset epilepsy.

PURPOSE: We aim to evaluate the utility/improved accuracy of hybrid PET/MR compared to current practice separate 3T MRI and PET-CT imaging for localization of seizure foci. METHOD: In a pilot study, twenty-nine patients undergoing epilepsy surgery evaluation were imaged using PET/MR. This subject group had 29 previous clinical 3T MRI as well as 12 PET-CT studies. Prior clinical PET and MR images were read sequentially while the hybrid PET/MR was concurrently read. RESULTS: The median interval between hybrid PET/MR and prior imaging studies was 5 months (range 1-77 months). In 24 patients, there was no change in the read between the clinical exams and hybrid PET/MR while new anatomical or functional lesions were identified by hybrid PET/MR in 5 patients without significant clinical change. Four new anatomical MR lesions were seen with concordant PET findings. The remaining patient revealed a new abnormal PET lesion without an MR abnormality. All new PET/MR lesions were clinically significant with concordant EEG and/or SPECT results as potential epileptic foci. CONCLUSION: Our initial hybrid PET-MRI experience increased diagnostic yields for detection of potential epileptic lesions. This may be due to the unique advantage of improved co-registration and simultaneous review of both structural and functional data.

Triple pathological findings in a surgically amenable patient with mesial temporal lobe epilepsy.

Mesial temporal sclerosis (MTS) is a well-recognized cause of intractable epilepsy; however, coexistence with focal cortical dysplasia (FCD) is less common. Middle fossa epidermoid cysts are rare and may involve the temporal lobe. Most epidermoids are clinically silent, slow-growing, and seldom associated with overt symptomatology, including seizures. We describe a patient with multiple comorbidities including left MTS and a large epidermoid cyst involving the left quadrigeminal plate cistern compressing upon the cerebellar vermis and tail of the left hippocampus, resulting in refractory left temporal lobe epilepsy. The patient underwent left anterior temporal lobectomy. The surgical pathology demonstrated a third pathological finding of left temporal FCD type Ia. The patient has been seizure-free since the surgery. This case provides additional information with regard to the understanding of epileptogenicity and surgical planning in patients with MTS and epidermoid cysts.

Dermatomyositis as a presentation of neuromyelitis optica spectrum disorder.

IMPORTANCE: This is the first report of neuromyelitis optica spectrum disorder (NMOSD) associated with dermatomyositis (DM). REPORT: A 40year-old Caucasian female presented with 6months of worsening fatigue, rash, acute weakness worse in her lower extremities, and urinary retention. She was found to have both NMOSD and anti-melanoma differentiation-associated gene (MDA)5 positive DM with interstitial lung disease (ILD). She was treated aggressively and she regained her ability to ambulate. CONCLUSION: We recommend considering NMOSD in the differential diagnosis of patients with DM and other autoimmune disorders that also present with clinical signs of myelopathy.

Clinical significance of indeterminate pulmonary nodules in patients with locally advanced head and neck squamous cell carcinoma.

BACKGROUND: The purpose of this study was to determine whether indeterminate pulmonary nodules (IPNs) at staging are predictive of lung metastasis, primary lung carcinoma, or survival in patients with advanced head and neck squamous cell carcinoma (HNSCC). METHODS: One hundred ten patients with IPN at staging who had follow-up imaging and 100 patients without IPN were identified from an HNSCC database. The primary endpoints were lung progression-free survival (PFS) and overall survival (OS). RESULTS: Two-year lung PFS for the IPN and No-IPN cohorts were 66% versus 61% (p = .92) and the OS for these cohorts were 71% versus 68% (p = .77). Within the IPN cohort, level IV/V lymph node involvement (odds ratio = 4.34; p = .03), hypopharynx primary (odds ratio = 21.5; p = .005), and race (odds ratio = 9.29; p = .001) were independent predictors of developing lung malignancy. CONCLUSION: IPNs at staging in patients with HNSCC do not affect prognosis and should neither influence initial treatment planning nor the frequency of posttreatment surveillance.

Magnetic resonance imaging of guinea pig cochlea after vasopressin-induced or surgically induced endolymphatic hydrops.

OBJECTIVE: To investigate the ability to detect the in vivo cochlear changes associated with vasopressin-induced and surgically induced endolymphatic hydrops using MRI at 3 tesla (T). STUDY DESIGN: Prospective, animal model. SETTING: Animal laboratory. SUBJECTS AND METHODS: In group 1, five guinea pigs underwent post-gadolinium temporal bone MRI before and after seven and 14 days of chronic systemic administration of vasopressin by osmotic pump. In group 2, five guinea pigs underwent temporal bone MRI eight weeks after unilateral surgical ablation of the endolymphatic sac. Three-tesla high-resolution T1-weighted sequences were acquired pre- and postcontrast administration. Region of interest signal intensities of the perilymph and endolymph were analyzed manually. Quantitative evaluation of hydrops was measured histologically. RESULTS: Gadolinium preferentially concentrated in the perilymph, allowing for distinction of cochlear compartments on 3.0-T MRI. The T1-weighted contrast MRI of vasopressin-induced hydropic cochlea showed significant increases in signal intensity of the endolymph and perilymph. Surgically induced unilateral hydropic cochlea also showed increased signal intensity, compared with the control cochlea of the same animal, but less of an increase than the vasopressin group. The histological degree of hydrops induced in the vasopressin group was comparable to previous studies. CONCLUSIONS: In vivo postcontrast MRI of the inner ear demonstrated cochlear changes associated with chronic systemic administration of vasopressin and surgical ablation of the endolymphatic sac. Understanding the MRI appearance of endolymphatic hydrops induced by various methods contributes to the future use of MRI as a possible tool in the diagnosis and treatment of Ménière's disease.

Progressive tumefactive inflammatory central nervous system demyelinating disease in an acquired immunodeficiency syndrome patient treated with highly active antiretroviral therapy.

We report here a case of progressive tumefactive inflammatory central nervous system (CNS) demyelinating disease in a human immunodeficiency virus (HIV)-seropositive patient treated with highly active antiretroviral therapy (HAART). Biopsy revealed diffuse macrophage and perivascular T-lymphocytic infiltrates with severe demyelination and relative axonal sparing. The disease progressed in a centrifugal fashion, to involve bihemispheric cerebral white matter, with subsequent central necrotic changes and atrophy. Treatment with HAART was discontinued, and inflammatory disease was treated with subcutaneous interferon (IFN)beta-1a. Massive brain edema was controlled with courses of intravenous corticosteroids. Following fulminant monophasic disease, the patient stabilized with no evidence of disease progression over long-term follow up. We propose that immune response reconstituted by HAART can unmask an autoimmune response in susceptible individuals, analogous to the enhanced immune response to the preexisting acquired immunodeficiency syndrome (AIDS) opportunistic infections. Therapeutic options are considered.

The Dandy-Walker variant: a case series of 24 pediatric patients and evaluation of associated anomalies, incidence of hydrocephalus, and developmental outcomes.

OBJECT: The Dandy-Walker complex is a continuum of aberrant development of the posterior fossa that has been associated with multiple congenital anomalies, radiographic abnormalities, and developmental delay. The Dandy-Walker variant (DWV) is a unique entity believed to represent a milder form of the complex, and is characterized by a specific constellation of radiographic findings. In this retrospective case series, the authors report the association of the DWV with other congenital anomalies, the associated radiographic findings linked with DWV, and the developmental outcome in this population. METHODS: The charts and radiographs of 10 male and 14 female patients treated between 2000 and 2006 were examined. The patients' mean gestational age was 35.6 weeks (range 23-41 weeks), and the mean follow-up period was 5.1 years (range 1 month-15 years). RESULTS: Three patients died. Associated anomalies included cardiac (41.7%), neurological (33.3%), gastrointestinal (20.8%), orthopedic (12.5%), and genitourinary (12.5%) abnormalities. Less common were pulmonary and psychiatric findings. Developmental delay was identified in 11 of the 21 patients for whom follow-up was available. Five of 6 patients with isolated DWV had a normal developmental course. Radiographic findings associated with DWV included corpus callosum dysgenesis in 20.8%, ventricular enlargement in 29%, and vermian rotation in 8.3%. Shunts were placed in 4 of 7 patients with ventriculomegaly. Using the two-tailed Pearson correlation, the authors determined that developmental outcome was solely affected by neurological deficits and that ventricular enlargement predicted the need for shunt placement. CONCLUSIONS: The DWV was associated with both extra- and intracranial anomalies. Associated radiographic abnormalities including ventriculomegaly were observed. Hydrocephalus requiring cerebrospinal fluid diversion may be indicated. Isolated DWV was associated with a good developmental outcome.

Paraganglioma of the sphenoid sinus: case report and review of literature.

We report a case of a 41-year-old woman who presented with occasional hemoptysis and hoarseness. Imaging showed a mass primarily in the sphenoid sinus but also extending into the right posterior ethmoid sinus and nasopharynx. Histology showed this mass to be a paraganglioma. We describe its computed tomography and magnetic resonance imaging findings, and we discuss the differential diagnosis and treatment.