ABSTRACT
Meningiomas are the most common neoplasms of the central nervous system, accounting for approximately 40% of all brain tumors. Surgical resection represents the mainstay of management for symptomatic lesions. Preoperative planning is largely informed by neuroimaging, which allows for evaluation of anatomy, degree of parenchymal invasion, and extent of peritumoral edema. Recent advances in imaging technology have expanded the purview of neuroradiologists, who play an increasingly important role in meningioma diagnosis and management. Tumor vascularity can now be determined using arterial spin labeling and dynamic susceptibility contrast-enhanced sequences, allowing the neurosurgeon or neurointerventionalist to assess patient candidacy for preoperative embolization. Meningioma consistency can be inferred based on signal intensity; emerging machine learning technologies may soon allow radiologists to predict consistency long before the patient enters the operating room. Perfusion imaging coupled with magnetic resonance spectroscopy can be used to distinguish meningiomas from malignant meningioma mimics. In this comprehensive review, we describe key features of meningiomas that can be established through neuroimaging, including size, location, vascularity, consistency, and, in some cases, histologic grade. We also summarize the role of advanced imaging techniques, including magnetic resonance perfusion and spectroscopy, for the preoperative evaluation of meningiomas. In addition, we describe the potential impact of emerging technologies, such as artificial intelligence and machine learning, on meningioma diagnosis and management. A strong foundation of knowledge in the latest meningioma imaging techniques will allow the neuroradiologist to help optimize preoperative planning and improve patient outcomes.
ABSTRACT
Alzheimer's Disease (AD) is characterized by its complex and heterogeneous etiology and gradual progression, leading to high drug failure rates in late-stage clinical trials. In order to better stratify individuals at risk for AD and discern potential therapeutic targets we employed a novel procedure utilizing cell-based co-regulated gene networks and polygenic risk scores (cbPRSs). After defining genetic subtypes using extremes of cbPRS distributions, we evaluated correlations of the genetic subtypes with previously defined AD subtypes defined on the basis of domain-specific cognitive functioning and neuroimaging biomarkers. Employing a PageRank algorithm, we identified priority gene targets for the genetic subtypes. Pathway analysis of priority genes demonstrated associations with neurodegeneration and suggested candidate drugs currently utilized in diabetes, hypertension, and epilepsy for repositioning in AD. Experimental validation utilizing human induced pluripotent stem cell (hiPSC)-derived astrocytes demonstrated the modifying effects of estradiol, levetiracetam, and pioglitazone on expression of APOE and complement C4 genes, suggesting potential repositioning for AD.
ABSTRACT
This study delineates the pivotal role of imaging within the field of neurology, emphasizing its significance in the diagnosis, prognostication, and evaluation of treatment responses for central nervous system (CNS) tumors. A comprehensive understanding of both the capabilities and limitations inherent in emerging imaging technologies is imperative for delivering a heightened level of personalized care to individuals with neuro-oncological conditions. Ongoing research in neuro-oncological imaging endeavors to rectify some limitations of radiological modalities, aiming to augment accuracy and efficacy in the management of brain tumors. This review is dedicated to the comparison and critical examination of the latest advancements in diverse imaging modalities employed in neuro-oncology. The objective is to investigate their respective impacts on diagnosis, cancer staging, prognosis, and post-treatment monitoring. By providing a comprehensive analysis of these modalities, this review aims to contribute to the collective knowledge in the field, fostering an informed approach to neuro-oncological care. In conclusion, the outlook for neuro-oncological imaging appears promising, and sustained exploration in this domain is anticipated to yield further breakthroughs, ultimately enhancing outcomes for individuals grappling with CNS tumors.
ABSTRACT
OBJECTIVE: Generally, anterior lumbar interbody fusion (ALIF) was believed superior to transforaminal lumbar interbody fusion (TLIF) in induction of fusion. However, many studies have reported comparable results in lumbosacral fusion rate between the two approaches. This study aimed to evaluate the realistic lumbosacral arthrodesis rates following ALIF and TLIF in patients with degenerative spondylolisthesis as measured by CT and radiology. METHODS: Ninety-six patients who underwent single-level L5-S1 fusion through ALIF (n = 48) or TLIF (n = 48) for degenerative spondylolisthesis at the Spine Center, University of California San Francisco, between October 2014 and December 2017 were retrospectively evaluated. Fusion was independently evaluated and categorized as solid fusion, indeterminate fusion, or pseudarthroses by two radiologists using the modified Brantigan-Steffee-Fraser (mBSF) grade. Clinical data on sex, age, body mass index, Meyerding grade, smoking status, follow-up times, complications, and radiological parameters including disc height, disc angle, segmental lordosis, and overall lumbar lordosis were collected. The fusion results and clinical and radiographic data were statistically compared between the ALIF and TLIF groups by using t-test or chi-square test. RESULTS: The mean follow-up period was 37.5 (ranging from 24 to 51) months. Clear, solid radiographic fusions were higher in the ALIF group compared with the TLIF group at the last follow-up (75% vs 47.9%, p = 0.006). Indeterminate fusion occurred in 20.8% (10/48) of ALIF cases and in 43.8% (21/48) of TLIF cases (p = 0.028). Radiographic pseudarthrosis was not significantly different between the TLIF and ALIF groups (16.7% vs 8.3%; p = 0.677). In subgroup analysis of the patients without bone morphogenetic protein (BMP), the solid radiographic fusion rate was significantly higher in the ALIF group than that in the TLIF group (78.6% vs 45.5%; p = 0.037). There were no differences in sex, age, body mass index, Meyerding grade, smoking status, or follow-up time between the two groups (p > 0.05). The ALIF group had more improvement in disc height (7.8 mm vs 4.7 mm), disc angle (5.2° vs 1.5°), segmental lordosis (7.0° vs 2.5°), and overall lumbar lordosis (4.7° vs 0.7°) compared with the TLIF group (p < 0.05). Overall complication rates were similar between the TLIF and ALIF groups (10.4% vs 8.33%; p > 0.999). CONCLUSIONS: With a minimum 2-year radiographic analysis of arthrodesis at lumbosacral level by radiologists, the rate of solid radiographic fusions was higher in the ALIF group compared with the TLIF group, whereas the TLIF group had a higher rate of indeterminate fusion. Radiographic pseudarthrosis did not differ significantly between the TLIF and ALIF groups.
Subject(s)
Lordosis , Spinal Fusion , Spondylolisthesis , Humans , Lordosis/surgery , Follow-Up Studies , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Spondylolisthesis/diagnostic imaging , Spondylolisthesis/surgery , Retrospective Studies , Postoperative Complications/etiology , Spinal Fusion/methods , Treatment OutcomeABSTRACT
Dedicated post-operative radiological evaluation following ophthalmologic procedures is relatively uncommon. However, given the ever-growing ophthalmologic procedural advancements and the increasing utilization of neuroimaging for myriad indications, the orbits are often imaged incidentally in a delayed post-procedural state. Regardless of the clinical scenario, it is important for neuroradiologists and other specialists commonly exposed to orbital imaging to be aware of both expected and abnormal post-operative imaging findings because misinterpreted normal features or unrecognized complications can result in vision-threatening delays in treatment or mismanagement. In this review article, we discuss many common ophthalmologic procedures, their indications, and most likely complications. We also provide illustrative operative photographs and radiological imaging examples. By understanding the surgical intent, recognizing the devices that are commonly used, and developing familiarity with the appearance of post-operative complications, pitfalls in interpretation can be avoided and patient outcomes ultimately improved.
Subject(s)
Diagnostic Imaging/methods , Ophthalmologic Surgical Procedures/adverse effects , Orbit/surgery , Postoperative Complications/diagnostic imaging , Humans , Orbit/diagnostic imaging , Postoperative Complications/etiologyABSTRACT
Use of optical coherence tomography (OCT) adds an assessment of thrombus burden remaining on stents after PCI for acute coronary syndromes. Potential variations in stent-related thrombus burden can be documented by OCT as a function of peri-procedural pharmacology supporting the use of OCT in future hypothesis testing. Bivalirudin remains a reliable and expensive alternative to heparin in cases of HIT or patients at high bleeding risk during transfemoral PCI.
Subject(s)
Percutaneous Coronary Intervention , Thrombosis , Heparin/adverse effects , Hirudins/adverse effects , Humans , Peptide Fragments , Percutaneous Coronary Intervention/adverse effects , Recombinant Proteins , Stents , Thrombosis/diagnostic imaging , Thrombosis/etiology , Tomography, Optical Coherence , Treatment OutcomeABSTRACT
Symmetrical peripheral gangrene (SPG) is a rare entity characterized by ischemic changes of the distal extremities with maintained vascular integrity. We present the case of a 64-year-old man with bilateral necrotic toes and deranged liver function tests. This was thought to be related to severely depressed ejection fraction from non-ischemic etiology, presumably chronic alcohol ingestion. We hope that awareness of SPG and association with a low output state will aid in early detection and prevention.
Subject(s)
Cardiac Output, Low/complications , Gangrene/etiology , Heart Failure/complications , Cardiac Output, Low/etiology , Echocardiography/methods , Electrocardiography/methods , Emergency Service, Hospital/organization & administration , Heart Failure/physiopathology , Humans , Male , Middle AgedABSTRACT
Takotsubo cardiomyopathy is characterized by transient apical ballooning with preserved basal ventricular function triggered by physical or emotional stressors. We present a case of a 75-year-old man referred to our facility for the management of acute myocardial infarction later diagnosed as takotsubo cardiomyopathy. We believe platelet-mediated adrenaline release from massive thrombocytosis might have been the precipitating factor for the pathogenesis of takotsubo cardiomyopathy.
ABSTRACT
Context: Sodium-glucose co-transporter 2 (SGLT-2) inhibitors are a novel treatment approved for type 2 diabetes mellitus to lower hyperglycemia, systolic blood pressure, and promote weight loss. Commonly reported serious adverse events include increased mycotic urogenital infections, orthostatic hypotension, and normoglycemic ketoacidosis. Case report: We present a case of a 47-year old man with a history of type 2 diabetes mellitus initiated on the SGLT-2 inhibitor canagliflozin preoperatively before a penile implant, who presented with late postoperative MRSA bacteremia and scrotal abscess requiring implant extraction. Conclusion: As the SGLT-2 inhibitors are gaining in popularity, prescribers must be aware of the potential adverse genitourinary infectious outcomes. Providers should use caution and avoid initiating SGLT-2 inhibitors in the perioperative setting, and may even consider holding or discontinuing this medication in the setting of impending GU surgery.
ABSTRACT
Disseminated mucormycosis endocarditis is extremely rare, and only a few cases have actually been reported in the literature. It is almost universally fatal despite aggressive surgical and medical management. In this article, we present the case of a 48-year-old immunocompromised male with mucormycosis endocarditis, who presented with acute bilateral lower extremity ischemia and passed away due to subsequent multi-organ failure. To our knowledge, this is the first case report of disseminated mucormycosis native valve endocarditis presenting as acute bilateral lower extremity ischemia.
ABSTRACT
Vertebral osteomyelitis due to Streptococcus viridans following a dental procedure is a rarely reported phenomenon. We discuss the case of a 67-year-old immunocompetent woman who presented with low back pain of 3â weeks duration associated with subjective fever and chills. On admission, the MRI of the lumbar spine showed L5-S1 vertebral osteomyelitis with associated paravertebral and epidural abscesses. Subsequently, detailed history was retaken and the patient reported having had a maxillary tooth extraction followed by a dental implant 2â months prior to the onset of her symptoms. Blood and abscess fluid cultures grew S. viridans Transthoracic echocardiogram showed no evidence of endocarditis. The patient was started on intravenous ceftriaxone but her treatment course was complicated by agranulocytosis requiring a switch to vancomycin. She required a total of 9â weeks of intravenous antibiotics for complete clinical cure.
Subject(s)
Low Back Pain/microbiology , Osteomyelitis/microbiology , Streptococcal Infections/complications , Tooth Extraction/adverse effects , Viridans Streptococci/isolation & purification , Aged , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/microbiology , Magnetic Resonance Imaging , Osteomyelitis/diagnostic imaging , Osteomyelitis/drug therapy , Streptococcal Infections/diagnosis , Streptococcal Infections/drug therapy , Streptococcal Infections/etiology , Vancomycin/administration & dosageABSTRACT
Gastric cancer is the 12th leading cause of cancer-related deaths in the United States and commonly metastasizes to the bones. However, the presentation of gastric cancer as bony metastases without preceding gastrointestinal symptoms is rare which has been infrequently reported in the literature. Moreover, leptomeningeal carcinomatosis is an unusual complication of gastric cancer accounting for less than 1 percent of these patients. We present a unique case of a middle aged male who presented to the emergency department with worsening backache which started one month priorly. The only abnormal laboratory test was an elevated alkaline phosphatase of 154 IU/L. The imaging of his spine showed osteolytic lesions which on biopsy revealed signet ring cells. A small 2 cm ulcerated mass was found on esophagogastroduodenoscopy at the gastric cardia which on biopsy revealed signet ring gastric carcinoma. The patient received chemotherapy with capecitabine and oxaliplatin as well as radiation and showed a good response initially. A few months later, he presented with persistent worsening headaches and on brain imaging was found to have leptomeningeal carcinomatosis. Ten months after the diagnosis of gastric carcinoma, he passed away.
ABSTRACT
A significant portion of our risk for dementia in old age is associated with lifestyle factors (diet, exercise, and cardiovascular health) that are modifiable, at least in principle. One such risk factor, high-homocysteine levels in the blood, is known to increase risk for Alzheimer's disease and vascular disorders. Here, we set out to understand how homocysteine levels relate to 3D surface-based maps of cortical gray matter distribution (thickness, volume, and surface area) computed from brain magnetic resonance imaging in 803 elderly subjects from the Alzheimer's Disease Neuroimaging Initiative data set. Individuals with higher plasma levels of homocysteine had lower gray matter thickness in bilateral frontal, parietal, occipital, and right temporal regions and lower gray matter volumes in left frontal, parietal, temporal, and occipital regions, after controlling for diagnosis, age, and sex and after correcting for multiple comparisons. No significant within-group associations were found in cognitively healthy people, patients with mild cognitive impairment, or patients with Alzheimer's disease. These regional differences in gray matter structure may be useful biomarkers to assess the effectiveness of interventions, such as vitamin B supplements, that aim to prevent homocysteine-related brain atrophy by normalizing homocysteine levels.
Subject(s)
Alzheimer Disease/diagnosis , Alzheimer Disease/pathology , Gray Matter/pathology , Homocysteine/blood , Magnetic Resonance Imaging , Neuroimaging , Aged , Aged, 80 and over , Alzheimer Disease/etiology , Alzheimer Disease/prevention & control , Atrophy , Biomarkers/blood , Female , Folic Acid/administration & dosage , Humans , Life Style , Male , Risk Factors , Vitamin B Complex/administration & dosageABSTRACT
Smaller hippocampal volume has been reported in individuals with post-traumatic stress disorder (PTSD) and dissociative identity disorder (DID), but the regional specificity of hippocampal volume reductions and the association with severity of dissociative symptoms and/or childhood traumatization are still unclear. Brain structural magnetic resonance imaging scans were analyzed for 33 outpatients (17 with DID and 16 with PTSD only) and 28 healthy controls (HC), all matched for age, sex, and education. DID patients met criteria for PTSD (PTSD-DID). Hippocampal global and subfield volumes and shape measurements were extracted. We found that global hippocampal volume was significantly smaller in all 33 patients (left: 6.75%; right: 8.33%) compared with HC. PTSD-DID (left: 10.19%; right: 11.37%) and PTSD-only with a history of childhood traumatization (left: 7.11%; right: 7.31%) had significantly smaller global hippocampal volume relative to HC. PTSD-DID had abnormal shape and significantly smaller volume in the CA2-3, CA4-DG and (pre)subiculum compared with HC. In the patient groups, smaller global and subfield hippocampal volumes significantly correlated with higher severity of childhood traumatization and dissociative symptoms. These findings support a childhood trauma-related etiology for abnormal hippocampal morphology in both PTSD and DID and can further the understanding of neurobiological mechanisms involved in these disorders.
Subject(s)
Child Abuse , Dissociative Identity Disorder/pathology , Dissociative Identity Disorder/psychology , Hippocampus/pathology , Stress Disorders, Post-Traumatic/pathology , Adult , Child , Child Abuse/psychology , Female , Functional Laterality , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Organ Size , Psychiatric Status Rating Scales , Stress Disorders, Post-Traumatic/psychologyABSTRACT
Morphology of the corpus callosum is a useful biomarker of neuronal loss, as different patterns of cortical atrophy help to distinguish between dementias such as Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). We used a sophisticated morphometric analysis of the corpus callosum in FTLD subtypes including frontotemporal dementia (FTD), semantic dementia (SD), and progressive non-fluent aphasia (PNFA), and compared them to AD patients and 27 matched controls. FTLD patient subgroups diverged in their callosal morphology profiles, with FTD patients showing marked widespread differences, PNFA patients with differences largely in the anterior half of the callosum, and SD patients differences in a small segment of the genu. AD patients showed differences in predominantly posterior callosal regions. This study is consistent with our previous findings showing significant cortical and subcortical regional atrophy across FTLD subtypes, and suggests that callosal atrophy patterns differentiate AD from FTLD, and FTLD subtypes.