Association between the degree of vertebrobasilar stenosis, location, infarction pattern, and QMRA flow state.

BACKGROUND AND PURPOSE: We aimed to investigate the relationship between the degree and location of vertebrobasilar stenosis and quantitative magnetic resonance angiography (QMRA) distal flow. METHODS: We retrospectively reviewed patients who presented with acute ischemic stroke with ≥50% stenosis of the extracranial or intracranial vertebral or basilar arteries, and QMRA performed within 1 year of stroke. Standardized techniques were used to measure stenosis and to dichotomize vertebrobasilar distal flow status. Patients were grouped based on the involved artery and the severity of disease. All p-values were calculated using chi-squared analysis and Fisher exact test with statistical significance defined as p < .05. RESULTS: Sixty-nine patients met study inclusion, consisting of 31 with low distal flow and 38 with normal distal flow. The presence of severe stenosis or occlusion was 100% sensitive, but only 47% predictive and 26% specific of a low distal flow state. Bilateral vertebral disease was only 55% sensitive but was 71% predictive and 82% specific of a low-flow state and was five times and nearly three times more likely to result in a low-flow state compared to unilateral vertebral disease (14%) and isolated basilar disease (28%), respectively. CONCLUSIONS: Severe stenosis of ≥70% may mark the minimal threshold required to cause hemodynamic insufficiency in the posterior circulation, but nearly half of these patients may remain hemodynamically sufficient. Bilateral vertebral stenosis resulted in a fivefold increase in QMRA low distal flow status compared to unilateral vertebral disease. These results may have implications in the design of future treatment trials of intracranial atherosclerotic disease.

Novel Grading Scales for Static and Flexion-Extension Magnetic Resonance Imaging in Patients with Cervical Spondylotic Myelopathy.

BACKGROUND: Flexion-extension magnetic resonance imaging (MRI) has potential to identify cervical pathology not detectable on conventional static MRI. Our study evaluated standard quantitative and novel subjective grading scales for assessing the severity of cervical spondylotic myelopathy in dynamic sagittal MRI as well as in static axial and sagittal images. METHODS: Forty-five patients underwent both conventional and flexion-extension MRI prior to anterior cervical discectomy and fusion from C4 through C7. In addition to measuring Cobb angles and cervical canal diameter, grading scales were developed for assessment of vertebral body translation, loss of disc height, change in disc contour, deformation of cord contour, and cord edema. Data were collected at all levels from C2-C3 through C7-T1. Variations in measurements between cervical levels and from flexion through neutral to extension were assessed using Mann-Whitney, Kruskal-Wallis, and two-way ANOVA tests. RESULTS: Cervical canal diameter, vertebral translation, and posterior disc opening changed significantly from flexion to neutral to extension positions (P < 0.01). When comparing operative versus nonoperative cervical levels, significant differences were found when measuring sagittal cervical canal dimensions, vertebral translation, and posterior disc opening (P < 0.01). Degenerative loss of disc height, disc dehydration, deformation of ventral cord contour, and cord edema were all significantly increased at operative levels versus nonoperative levels (P < 0.01). CONCLUSIONS: Flexion-extension MRI demonstrated significant changes not available from conventional MRI. Subjective scales for assessing degenerative changes were significantly more severe at levels with operative cervical spondylotic myelopathy. The utility of these scales for planning surgical intervention at specific and adjacent levels is currently under investigation.

Stroke mechanisms in adult moyamoya disease: The association between infarction patterns and quantitative magnetic resonance angiography flow state.

INTRODUCTION: Flow augmentation is the mainstay treatment for moyamoya disease as hemodynamic failure is believed to be the dominant mechanism. We aimed to investigate the mechanisms of stroke in moyamoya disease by assessing the relationship between infarction patterns and quantitative magnetic resonance angiography flow state. METHODS: A retrospective study of adult patients with suspected MMD who presented with MRI confirmed acute ischemic stroke predating or following QMRA by a maximum of six months between 2009 and 2021 was conducted. Of the 177 consecutive patients with MMD who received QMRA, 35 patients, consisting of 41 hemispheres, met inclusion criteria. Flow-status was dichotomized into low-flow and normal-flow state based on previously established criteria. RESULTS: Mixed infarction pattern was the most frequent finding (70.7 %), followed by embolic (17.1 %), perforator (7.3 %), and internal borderzone (IBZ) (4.9 %). Infarction patterns were further dichotomized into IBZ+ (internal borderzone alone or mixed) and IBZ- (no internal borderzone constituent). Low-flow states were not significantly more frequent in the IBZ+ compared to IBZ- population (48.4 % vs. 20.0 %, p = 0.14). Ipsilateral posterior cerebral artery fractional flow was significantly higher with IBZ+ compared to IBZ- (345.0 % vs. 214.7 %, p = 0.04). CONCLUSION: Mixed infarction pattern was the most common pattern of infarction in patients with moyamoya disease, implying hypoperfusion and thromboembolism are codominant stroke mechanisms. An association between ICA flow status and infarction pattern was not found, although QMRA evidence of more robust posterior cerebral artery leptomeningeal collaterals was found in patients with a hypoperfusion contribution to their stroke mechanism.

Vertebrobasilar Stroke: Association Between Infarction Patterns and Quantitative Magnetic Resonance Angiography Flow State.

Background Treatment and prognosis of vertebrobasilar atherosclerotic disease differs depending on stroke mechanism, such as artery-to-artery embolism, branch atheromatous disease, and hemodynamic ischemia. Our aim was to investigate the relationship between infarction pattern and flow status using quantitative magnetic resonance angiography (QMRA), to determine the validity of using infarction patterns to infer stroke mechanism. Methods and Results This is a retrospective study of patients with ischemic stroke with intra- or extracranial vertebrobasilar atherosclerotic stenosis, who underwent magnetic resonance imaging of the brain, neurovascular imaging, and QMRA, between 2009 and 2021. Patients with cerebral infarction predating or following QMRA by ≥1 year, or QMRA studies performed for basilar thrombosis, vertebral dissection, or only postangioplasty/stenting, were excluded. Poststenotic flow (basilar and posterior cerebral arteries) was dichotomized as low-flow or normal-flow based on published criteria. Of 1211 consecutive patients who underwent QMRA noninvasive optimal analysis, 69 met inclusion. Mixed patterns were most common (46.4%), followed by perforator (23.2%), borderzone (14.5%), and territorial (15.9%). Patients with low-flow had a significantly higher rate of borderzone+ patterns (borderzone alone or in mixed pattern) compared with patients with normal-flow (77.4% low-flow versus 39.5% normal-flow, P=0.002). Borderzone+ patterns were associated with 61.5% probability of low-flow state, while no borderzone (perforator/territorial) patterns were associated with 76.7% probability of normal-flow state. Conclusions Borderzone infarction pattern (alone or mixed) was associated with low poststenotic posterior circulation flow by QMRA. However, borderzone pattern only moderately predicted low-flow state, and may be an unreliable flow marker. Therefore, infarct topography may complement, but should not replace hemodynamic studies to establish flow status.

MRI Dynamic Contrast Imaging of Oral Cavity and Oropharyngeal Tumors.

ABSTRACT: In the past decade, dynamic contrast-enhanced magnetic resonance imaging has had an increasing role in assessing the microvascular characteristics of various tumors, including head and neck cancer. Dynamic contrast-enhanced magnetic resonance imaging allows noninvasive assessment of permeability and blood flow, both important parametric features of tumor hypoxia, which is in turn a marker for treatment resistance for head and neck cancer.In this article we will provide a comprehensive review technique in evaluating tumor proliferation and application of its parameters in differentiating between various tumor types of the oral cavity and how its parameters can correlate between epidermal growth factor receptor and human papillomavirus which can have an implication in patient's overall survival rates.We will also review how the parameters of this method can predict local tumor control after treatment and compare its efficacy with other imaging modalities. Lastly, we will review how its parameters can be used prospectively to identify early complications from treatment.

Fluorescence-Guided High-Grade Glioma Surgery More Than Four Hours After 5-Aminolevulinic Acid Administration.

Background: Fluorescence-guided surgery (FGS) using 5-aminolevulic acid (5-ALA) is a widely used strategy for delineating tumor tissue from surrounding brain intraoperatively during high-grade glioma (HGG) resection. 5-ALA reaches peak plasma levels ~4 h after oral administration and is currently approved by the FDA for use 2-4 h prior to induction to anesthesia. Objective: To demonstrate that there is adequate intraoperative fluorescence in cases undergoing surgery more than 4 h after 5-ALA administration and compare survival and radiological recurrence to previous data. Methods: Retrospective analysis of HGG patients undergoing FGS more than 4 h after 5-ALA administration was performed at two institutions. Clinical, operative, and radiographic pre- and post-operative characteristics are presented. Results: Sixteen patients were identified, 6 of them female (37.5%), with mean (SD) age of 59.3 ± 11.5 years. Preoperative mean modified Rankin score (mRS) was 2 ± 1. All patients were dosed with 20 mg/kg 5-ALA the morning of surgery. Mean time to anesthesia induction was 425 ± 334 min. All cases had adequate intraoperative fluorescence. Eloquent cortex was involved in 12 cases (75%), and 13 cases (81.3%) had residual contrast enhancement on postoperative MRI. Mean progression-free survival was 5 ± 3 months. In the study period, 6 patients died (37.5%), mean mRS was 2.3 ± 1.3, Karnofsky score 71.9 ± 22.1, and NIHSS 3.9 ± 2.4. Conclusion: Here we demonstrate that 5-ALA-guided HGG resection can be performed safely more than 4 h after administration, with clinical results largely similar to previous reports. Relaxation of timing restrictions could improve procedure workflow in busy neurosurgical centers, without additional risk to patients.

Neurolymphomatosis of the peripheral nervous system: a case report and review of the literature.

Neurolymphomatosis is a rare neurological syndrome in lymphomas. It is reported as infiltration of peripheral nerves by lymphoma. It is important to distinguish neurolymphomatosis from other types of neuropathies, particularly infectious and inflammatory conditions. However, it is difficult to isolate a cancer-related inflammatory vasculitis and mononeuritis multiplex without definitive histopathologic examination. In this report, we describe a case of non-Hodgkin's lymphoma involving the peroneal nerve and presenting as neurolymphomatosis.

PET/CT presentation of primary effusion lymphoma-like lymphoma unrelated to human herpes virus 8, a rare NHL subtype.

We present a 71-year-old female with human herpes virus 8 (HHV8)-unrelated primary effusion lymphoma (PEL)-like lymphoma. Dyspnea and pericardial effusion led to pericardiocentesis, diagnosing diffuse large B-cell lymphoma. She underwent positron emission tomography/computed tomography (PET/CT), which demonstrated hypermetabolic pericardial, pleural, and ascites fluid without lymphadenopathy elsewhere. Malignant fluid in the absence of lymphadenopathy is a hallmark of PEL. PEL is associated with immunodeficiency states such as acquired immunodeficiency syndrome (AIDS) and infectious agents such as HHV8. Our patient had no such history and had not received immunosuppressive chemotherapy. We present the PET/CT findings of this rare case of HHV8-unrelated PEL-like lymphoma.

"How we do it" - a practical approach to hepatic metastases ablation techniques.

Secondary liver malignancies are associated with significant mortality and morbidity if left untreated. Colorectal cancer is the most frequent origin of hepatic metastases. A multidisciplinary approach to the treatment of hepatic metastases includes medical, surgical, radiation and interventional oncology. The role of interventional oncology in the management of hepatic malignancies continues to evolve and applies to a large and continuous spectrum of metastatic disease, from the relatively small solitary metastasis to larger tumors and multifocal liver disease. Within the past 10 years, several publications of percutaneous image-guided ablation indicated the effectiveness and safety of this minimally invasive therapy for selected patients with limited number (arguably up to 4 metastases) of relatively small (less than 5cm) hepatic metastases. Different image-guided procedures such radiofrequency, microwave, and laser cause thermal ablation and coagulation necrosis or cell death of the target tumor. Cryoablation, causing cell death via cellular freezing, has also been used. Recently, irreversible electroporation, a nonthermal modality, has also been used for liver tumor ablation. In the following section, we review the different liver ablation techniques, as well as indications for ablation, specific patient preparations, and different "tricks of the trade" that we use to achieve safe and effective liver tumor ablation. We also discuss appropriate imaging and clinical patient follow-up and potential complications of liver tumor ablation.

Mycobacterial pseudotumor of the plantar fascia: how common is it?

Mycobacterial spindle cell pseudotumor (MSCP) is an extremely rare complication of mycobacterial infections. It has been reported to occur in various sites such as skin, lymph nodes, bone marrow, lungs, and spleen. This tumor-like lesion can be confused clinically as well as radiographically with dermatofibroma, nodular fasciitis, xanthogranuloma, and Kaposi's sarcoma. While this lesion is rare and has been previously reported to occur only in superficial skin, we emphasize its consideration and inclusion in the differential diagnoses when a deep soft tissue mass is complicated by symptoms of deep tissue infection secondary to abscess formation in immunocompromised hosts. Here, we present the clinical and radiologic findings of a case of MSCP involving the deep plantar sheaths.

Simultaneous presentation in the neck and abdomen of malignant peripheral nerve sheath tumors involving two different nerve tracts.

Neurofibromatosis-1 (NF-1) is a relatively common autosomal dominant disease and it is caused by mutation of the NF-1 tumor suppressor gene; hence, the individuals affected have increased risk for developing familial cancer. Abdominal cavity neurofibromas are common but the simultaneous occurrence of a malignant peripheral nerve sheath tumor (MPNST) in the chest and in the abdomen is rare. Here, we present a patient with MPNST (spindle cell sarcoma) affecting simultaneously the vagus nerve in the head and neck region, mediastinum, pleura as well as celiac plexus branches near the stomach.

Radionuclide therapy of painful bone metastases--a comparative study between consecutive radionuclide infusions, combination with chemotherapy, and radionuclide infusions alone: an in vivo comparison of their effectiveness.

Radionuclides have been long used for the palliation of skeletal-related metastatic pain. They are almost invariably used as the last resource for pain palliation. Their use as single agents with dose escalations, in combination with biphosphonates or chemotherapy is well known in the peer-reviewed literature; however, little is known about the combination between different agents. In our study, we used consecutive administration of 2 different radionuclides such as (186)Re-1,1-hydroxyethylidenediphosphonate ((186)Re-HEDP) and (89)Strontium Chloride ((89)Sr-Cl) separated by adequate period of time to allow bone marrow recovery in patients with high chance of bone pain relapse and compared it with (89)Sr-Cl and chemotherapy group and (186)Re-HEDP with bisphosphonates. The end result was that treatment with consecutive radionuclides was much more effective and safe than the other 2 groups.

Extreme clinical presentations of venous stasis: coronary sinus thrombosis.

Sixty six year old male with history of heart failure was admitted for dysphagia, weight loss. CT scan chest revealed diffuse oesophageal wall thickening. Upper endoscopy, oesophagogram confirmed diagnosis of achalasia. TTE revealed severely reduced biventricular systolic function with LVEF 10%; PASP 75-80 mmHg. Parasternal long views showed dilated coronary sinus with a visible, mobile 2.0 cm thrombus. Pro-thrombotic workup was negative. Coronary sinus thrombosis has been identified as a rare complication to invasive cardiac procedures causing damage to coronary sinus endothelium and in hypercoagulable states.Typically acute thrombosis presents with chest pain, dynamic ECG changes, but chronic development does not present with ischaemic signs due to formation of efficient collateral circulation. We present a case report of stable primary coronary sinus thrombus incidentally diagnosed, secondary to chronic venous stasis in coronary circulation. Currently, there are no guidelines to assist physicians in long term management of such patients and thus warrants further investigations.

Middle cerebral artery involvement in systemic lupus erythematosus presenting as a stroke--an unusual initial presentation of the disease.

Systemic lupus erythematosus (SLE) disproportionately affects the African American population and usually presents with a constellation of symptoms. Along with hematologic, musculoskeletal, serous and skin involvement, the most common causes of morbidity are attributed to altered blood rheology causing accelerated atherosclerotic vascular disease (ASVD). ASVD occurs in predominantly premenopausal women at an age where ASVD is rare or uncommon. Classical central nervous system manifestations are very rare from the outset of the disease. Here we present a 44-year old African American woman with newly diagnosed SLE and no significant atherosclerotic risk factors, who presented initially with symptoms of subacute stroke.

Superselective internal radiation with yttrium-90 microspheres in the management of a chemorefractory testicular liver metastasis.

We treated a patient with biopsy-proven, chemotherapy-resistant testicular cancer liver metastasis using Y-90 selective internal radiation treatment. We chose yttrium-90 rather than surgery and ablation due to tumor location and size as well as the patient's clinical history. The result was marked tumor response by positron emission tomography and computed tomography as well as significant improvement of the patient's quality of life accompanied by a substantial decrease of his tumor markers.

Ablation for the management of pulmonary malignancies.

OBJECTIVE: Surgical resection remains the treatment of choice for patients with early-stage primary lung cancer and selected patients with limited metastatic lung disease. However, surgery is a high-risk treatment for patients with coexisting morbidities, severe chronic obstructive pulmonary disease, a single lung, or a history of prior resection. The indications for and outcomes of ablative therapies performed for the management of pulmonary malignancies are discussed. CONCLUSION: Preservation of residual lung parenchyma when treating patients with early-stage primary lung cancer and those with limited metastatic lung disease is vital and can be achieved with image-guided thermal ablation therapies.

FDG PET/CT of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease.

The term extranodal disease refers to lymphomatous infiltration of anatomic sites other than the lymph nodes. Almost any organ can be affected by lymphoma, with the most common extranodal sites of involvement being the stomach, spleen, Waldeyer ring, central nervous system, lung, bone, and skin. The prevalence of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease has increased in the past decade. The imaging characteristics of extranodal involvement can be subtle or absent at conventional computed tomography (CT). Imaging of tumor metabolism with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) has facilitated the identification of affected extranodal sites, even when CT has demonstrated no lesions. More recently, hybrid PET/CT has become the standard imaging modality for initial staging, follow-up, and treatment response assessment in patients with lymphoma and has proved superior to CT in these settings. Certain PET/CT patterns are suggestive of extranodal disease and can help differentiate tumor from normal physiologic FDG activity, particularly in the mucosal tissues, bone marrow, and organs of the gastrointestinal tract. Familiarity with the different extranodal manifestations in various locations is critical for correct image interpretation. In addition, a knowledge of the differences in FDG avidity among the histologic subtypes of lymphoma, appropriate timing of scanning after therapeutic interventions, and use of techniques to prevent brown fat uptake are essential for providing the oncologist with accurate information.