Radiology of Recreational Drug Abuse

Cardiovascular and pulmonary complications of recreational drugs: A pictorial review

Recreational drug abuse constitutes a serious health problem worldwide. Consumption of cocaine, amphetamine-type stimulants, opioids and cannabis can lead to multiple acute and chronic cardiopulmonary complications, resulting in high morbidity and mortality. These complications may be first detected at imaging, since clinical presentation is usually non-specific. Cardiovascular complications include myocardial infarction, endocarditis, aortic dissection, infectious pseudoaneurysm, retained needle fragments, cardiomyopathy and pulmonary arterial hypertension. Pulmonary complications encompass pulmonary oedema, crack lung, pneumonia, septic emboli, barotrauma, airway disease, emphysema and excipient lung disease. Knowledge of the cardiopulmonary imaging manifestations of illicit drug use in conjunction with clinical history and a high grade of suspicion enable an accurate diagnosis and appropriate management plan. In this article we aim to provide a pictorial review of the most frequent cardiopulmonary manifestations of recreational drugs, emphasizing the underlying pathophysiologic mechanisms and the various imaging appearances.

Spectrum of Thoracic Imaging Findings in the Setting of Substance Abuse

ABSTRACT

Substance abuse continues to be prevalent nationwide and can lead to a myriad of chest pathologies. Imaging findings are vast and can include nodules, masses, ground-glass opacities, airspace disease, and cysts. Radiologists with awareness of these manifestations can assist in early identification of disease in situations where information is unable to be obtained from the patient. This review focuses on thoracic imaging findings associated with various forms of substance abuse, which are organized by portal of entry into the thorax: inhalation, ingestion, and injection.

Imaging of Drug-Related Vasculopathy

Illicit and recreational drugs, such as cocaine, heroin, amphetamines, and marijuana, can result in drug-related vasculitis or vasculopathy. Similarly, the use of certain antithyroid, oncologic, and immunosuppressive medications for therapeutic purposes can lead to vasculopathy. This in turn may result in significant complications in the central nervous system, including intracranial hemorrhage and stroke. Cocaine abuse can also lead to midline destructive lesions of the sinonasal complex. MR imaging, Vessel Wall imaging, and CT/CTA are valuable imaging tools for the evaluation of patients with suspected drug-induced vasculopathy or vasculitis. This article reviews the pathomechanism, clinical presentation, and imaging findings of vasculopathy related to drug abuse and prescribed medications.

Spontaneous Pneumothorax Secondary to Bullous Lung Emphysema Positive for Cannabinoids upon Toxicological Examination

Cannabis can be related to respiratory diseases, but the relationship between smoking marijuana and the development of a pneumothorax has scarcely been investigated. We aimed to analyze, in patients with a history of cannabis smoking abuse submitted to lung apicectomy for a primary spontaneous pneumothorax (PSP), the correlation between the presence of cannabinoids in the resected lung and the detection of bullous emphysema within the same tissue. Patients undergoing lung apicectomy for a PSP were prospectively enrolled, and the correlation between the presence of cannabinoids in the resected lung tissue and histological finding of bullous emphysema was investigated with Fisher's exact test. There were 21 male patients, with a median age of 27 years. The cannabinoids found by the toxicological examination in surgical specimens were mainly delta-9-tetrahydrocannabinol (THC), cannabinol (CBN), and cannabidiol (CBD). In 14/21 patients, cannabinoids were detected in the resected lung tissue, and bullous emphysema was present in 13/14 of these (93%), while bullous emphysema was found in only 1/7 (14%) of the remaining patients who were negative for cannabinoids in the lung tissue, and the difference was found to be statistically significant (p < 0.0009). Our study demonstrated the presence of bullous emphysema in most cannabinoid-positive patients and its absence in most of those who were cannabinoid-negative, supporting the correlation between cannabinoids in the lung tissue and bullous emphysema with the development of a "secondary" spontaneous pneumothorax.

Candida dubliniensis Fungemia Leading to Infective Endocarditis and Septic Pulmonary Emboli

Illicit drugs, especially those injected intravenously, are becoming increasingly more common worldwide. Individuals who use intravenous drugs often reuse or share needles which predisposes them to life-threatening infections. We present the case of a patient who was injecting intravenous drugs into her internal jugular vein, which eventually led to acutely worsening sepsis secondary to fungal infective endocarditis and bilateral septic pulmonary emboli. Transthoracic echocardiogram demonstrated multilobulated and spherical vegetations on the tricuspid and mitral valves, respectively. On computed tomography of the thorax, numerous cavitary lesions and ground-glass opacities were present in both lungs. Multiple hyperdense, linear structures consistent with broken needles were seen on chest radiography. It is important for radiologists to recognize the possibility of broken needles in patients with a history of intravenous drug use as astute recognition of broken needles may lead to better source control and improved outcomes.

Ischemic Infarction in Young Adults

Ischemic strokes in young adults are increasing in incidence and have emerged as a public health issue. The radiological features are not only diagnostic in identifying ischemic infarctions but also provide important clues in the investigation of the underlying causes or in the identification of risk factors. According to the different imaging patterns associated with ischemic stroke in young adults, the causes can be classified into 5 categories: cardioembolism, large vessel vasculopathy, small vessel vasculopathy, toxic-metabolic, and hypercoagulable disorders. The radiological features of each category and cause are described and summarized in this review.

A breath of not so fresh air…

Despite being widely used as a recreational drug, "poppers" lack a legal framework for their delivery. Their composition may vary largely. This report describes a case of severe bronchiolitis following amyl nitrite mixture inhalation. https://bit.ly/3p3S7LM.

Sequelae of Eating Disorders at Imaging

Although eating disorders are common, they tend to be underdiagnosed and undertreated because social stigma tends to make patients less likely to seek medical attention and less compliant with medical treatment. Diagnosis is crucial because these disorders can affect any organ system and are associated with the highest mortality rate of any psychiatric disorder. Because of this, imaging findings, when recognized, can be vital to the diagnosis and management of eating disorders and their related complications. The authors familiarize the radiologist with the pathophysiology and sequelae of eating disorders and provide an overview of the related imaging findings. Some imaging findings associated with eating disorders are nonspecific, and others are subtle. The presence of these findings should alert the radiologist to correlate them with the patient's medical history and laboratory results and the clinical team's findings at the physical examination. The combination of these findings may suggest a diagnosis that might otherwise be missed. Topics addressed include (a) the pathophysiology of eating disorders, (b) the clinical presentation of patients with eating disorders and their medical complications and sequelae, (c) the imaging features associated with common and uncommon sequelae of eating disorders, (d) an overview of management and treatment of eating disorders, and (e) conditions that can mimic eating disorders (eg, substance abuse, medically induced eating disorders, and malnourishment in patients with cancer). Online supplemental material is available for this article. ^©RSNA, 2022.

Cocaine-related cervical spinal cord infarction: a case report and review of the literature

Study design

Case report.

Objectives

To report a clinical case of spinal cord infarction due to cocaine use.

Setting

Spinal Center, IRCCS Fondazione S. Lucia, Rome (Italy).

Case presentation

Two days after recreational use of cocaine, a 27-year-old Caucasic man was admitted to the emergency department for acute cervical pain, weakness in all four limbs, and urinary retention. A cervical spinal magnetic resonance imaging scan, performed after 2 days, showed a “pencil-like” lesion extending from C4 to T1 metamer, compatible with acute ischemia in the anterior spinal artery territory. Other causes of vascular disorders, as well as inflammatory and infectious disorders were ruled out. At admission in our department, the patient had an incomplete tetraplegia at level C6, an indwelling catheter, and was unable to stand and walk. After 3 months of rehabilitation, he had an AIS score D tetraplegia at level C7, was able to stand and walk using parallel bars, and indwelling catheter was replaced by intermittent catheterization.

Discussion and conclusions

The etiology of medullary infarction may remain unexplained in nearly 30–40% of cases. Even if rare, cocaine-induced ischemic myelopathy should be considered and ruled out in the differential diagnosis of any acute nontraumatic myelopathy, especially in young patients.

Parkinson's Disease-Related Biomarkers That May Appear in Amphetamine Abusers

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. Amphetamine addiction may cause serious of psychotic and physical damage to humans. There is some evidence that shows that amphetamine may increase the risk of PD. Thus, this study is aimed at comparing the PD serum biomarkers between amphetamine addicts and PD patients and utilizing them as diagnostic biomarkers for the early detection of PD incidence among amphetamine addicts. In the current study, nineteen amphetamine addicts, aged <40, were recruited from the Al Amal Psychiatric hospital, Jazan, Saudi Arabia. Nineteen PD patients and 19 healthy controls, who have never taken amphetamine, were also recruited. Blood samples were withdrawn from all groups. A biomarker multiplex assay from MILLIPLEX was used to assess the levels of serum amyloid-P (SAP), complement C4, C-reactive protein (CRP), and CRP/albumin ratio in serum samples (Vitros 350® slide was used to assess the albumin). All data were statistically analyzed using one-way ANOVA. The results showed that SAP and CRP levels were significantly higher in amphetamine addicts compared to healthy controls (p = 0.0001 and p = 0.0001, respectively). The results of amphetamine addicts were comparable to PD levels. However, there are no significant differences between all studied groups concerning complement C4 level. Moreover, albumin levels were significantly decreased and CRP/Albumin ratio levels were significantly increased in amphetamine addicts (p = 0.01 and p = 0.041, respectively) in contrast with controls. These findings indicate that the increased level of these inflammatory biomarkers (SAP and CRP) in the amphetamine addicts may give a potential possibility of their serum level to be used as screening markers to detect PD development in the amphetamine addict. It may be useful to evaluate the changes in easily accessible and cost-effective parameters such as the serum CRP/albumin ratio.

Drug-related demyelinating syndromes: understanding risk factors, pathophysiological mechanisms and magnetic resonance imaging findings

Some drugs and medications can precipitate immune system deregulations, which might be confused with recurrent demyelinating diseases, such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMO), exacerbations of an existing disease, neoplastic lesions or other conditions. In this narrative review we describe some of the most relevant drugs and medications associated with iatrogenic demyelination. The anthelminthic agent levamisole is a frequent cocaine adulterant and can precipitate an exacerbated immune response attacking the central nervous system (CNS). High-efficacy multiple sclerosis (MS) drugs might induce a selective CNS immunosuppression, making it susceptible for opportunistic infections that course with demyelination, such as progressive multifocal leukoencephalopathy. Sometimes, the interruption of a high-efficacy drug to treat MS can induce a rapid CNS reentry of lymphocytes, exacerbating demyelinating processes and triggering rebound syndromes. Furthermore, selective cytokines inhibition, such as anti-TNFα agents, might induce an imbalance between cell death and proliferation inducing a paradoxical increase of CNS tumor necrosis factor (TNF), affecting the activity of lymphocytes, microglia and macrophages, triggering aberrant inflammation and demyelination. Immune checkpoint inhibitors are a new class of antineoplastic drugs that enhance the immune response against tumor cells by an upregulation of T-cell activity. However, this hyperactivation of the immune system might be associated with induction of unwanted autoimmune responses. In this paper we review the risk factors, the possible pathological mechanisms and the magnetic resonance imaging (MRI) findings of these drug-related demyelinating syndromes.

Cracking the Opium Den: Cardiothoracic Manifestations of Drug Abuse

Recreational drug use is increasing worldwide, with emergency room visits and total deaths from drug overdose rising in recent years. Complications from prescription and recreational drug use may result from the biochemical effects of the drugs themselves, impurities mixed with substances, or from causes related to the method of drug administration. The presentation of drug overdose may be complex due to multisubstance abuse, including cigarette smoking and alcoholism, and can impact any organ system. Patients may present without history, and radiologists may be the first clinicians to suggest the diagnosis. We aim to explore the cardiothoracic manifestations of drug abuse and their multimodality imaging manifestations.

Amphetamine-induced small bowel ischemia - A case report

Nonocclusive mesenteric ischemia is most common in elderly patients with multiple comorbidities. Nevertheless, there are some reports of acute bowel ischemia in young patients with a history of recreational drug abuse. We describe the case of a 33-year-old patient who presented with acute abdominal pain following amphetamine consumption. Multidetector computed tomography showed nonocclusive segmental ischemia of the distal ileum, and the patient underwent emergency surgery with ileocecal resection. The patient recovered quickly and was discharged without any postoperative complications. An early and precise diagnosis of patients with intestinal ischemia having a history of amphetamine abuse is of utmost importance for prompt and proper treatment. Especially in younger patients, multidetector computed tomography should be tailored to use with less radiation. A single portal venous scan proved sufficient in our case.

The needle and the damage done: musculoskeletal and vascular complications associated with injected drug use

Injected drug use is associated with a wide range of medical complications which are predominantly musculoskeletal and vascular in nature. Illicit drug use is increasing worldwide. Patients with complications of injected drug use often present in a non-specific manner without a reliable clinical history. Musculoskeletal complications are typically infective in aetiology and may vary widely in severity from mild to life-threatening. A multimodal imaging approach is often required for both diagnostic imaging and image-guided sampling. Plain radiographs are often an important initial test, for example in identifying retained needles from injection. Ultrasound and CT play important roles in the assessment of complex soft tissue complications and MRI is the imaging modality of choice for bone and joint disorders. Vascular complications may be venous or arterial in nature and usually occur locally at the injection site. These complications may be related to direct injury to the vessel wall by a needle, or secondary to local infection and inflammation. A multimodal imaging strategy is also often required in the assessment of these vascular complications, typically involving a combination of ultrasound and CT. Familiarity with the multimodal imaging features of the complications related to injected drug use is crucially important as they may be rapidly progressive and life-threatening and require timely diagnosis.

Candida Parapsilosis associated rice bodies in the extensor compartment of the wrist--an emerging finding

Candida parapsilosis has been considered an emerging pathogen with increasing incidence reported in the literature. As a normal commensal of human skin, it is likely that Candida species could gain access to soft tissues of the hand and wrist by direct inoculation, resulting in an infectious tenosynovitis. With the increased prevalence of intravenous drug use (IVDU), users are at increasing risk for musculoskeletal infections including soft tissue abscesses, cellulitis, tenosynovitis, and septic arthritis. Chronic tenosynovitis, with rice body formation in particular, is a comparatively rare musculoskeletal infection. Knowledge of this entity, the related pathogens, imaging findings, and the treatment plan is important not only to the treating clinician, but also to radiologists as the physiological and anatomic consequences can be detrimental to patient recovery.

Cytotoxic Lesions of the Corpus Callosum Caused by Thermogenic Dietary Supplements

Consumption of over-the-counter dietary supplements to reduce body weight is common among the population. Thermogenics are herbal combinations that claim to produce a fat-burning process through an increase in the cellular metabolic rate and greater cellular energy consumption, having a high risk for patients developing toxic leukoencephalopathy. We present a series of 6 patients with acute neurologic symptoms and MR imaging showing restricted diffusion and decreased apparent diffusion coefficient values (mean value, 400 mm²/s × 10^-6) in the entire corpus callosum compatible with a cytotoxic lesion of the corpus callosum. Although patients responded favorably to the product discontinuation with rapid recovery of neurologic symptoms, there was a more prolonged resolution on imaging alterations. Because of the widespread availability and unregulated nature of thermogenic dietary supplements, physicians must be aware of the clinical and radiologic characteristics of these potential complications of their use.

Bilateral Basal Ganglia Infarction After Intranasal Use of Cocaine: A Case Report

We present a case of a young man who developed bilateral basal ganglia infarct after intranasal use of cocaine. Cerebral ischemic infarcts are a known complication of cocaine use. This complication is rare and has been reported in the past with cocaine and concomitant use of other drugs such as heroin and amphetamines.

Radiographic Musculoskeletal Findings Indicating Opioid Misuse: An Overview for Orthopedic Surgeons

BACKGROUND

Given the high prevalence of musculoskeletal conditions in the USA, it is important for orthopedic surgeons to promptly identify patients who may be at risk for opioid misuse.

QUESTIONS/PURPOSES

The aim of this literature review was to elucidate various musculoskeletal pathologies and complications, as seen on imaging, that may indicate opioid misuse or opioid use disorder.

METHODS

A literature search was conducted using the PubMed, Scopus, and Cochrane Library databases for articles related to imaging findings associated with chronic opioid use or misuse in orthopedic patients. Two independent reviewers conducted the search utilizing pertinent Boolean operations.

RESULTS

We reviewed 36 full-text articles and categorized the radiographic evidence of opioid misuse as follows: soft-tissue radiologic findings, cellulitis, necrotizing fasciitis, abscess formation, retained needles, discitis, myopathy and rhabdomyolysis, osteomyelitis, septic arthritis, and septic thrombophlebitis.

CONCLUSION

Knowledge of the radiologic findings of opioid misuse will assist orthopedic surgeons in making timely diagnoses that may alter therapeutic regimens for their patients.

Multidetector CT of iatrogenic and self-inflicted vascular lesions and infections at the groin

Abstract

The number and complexity of endovascular procedures performed via either arterial or venous access are steadily increasing. Albeit associated with higher morbidity compared to the radial approach, the traditional common femoral artery remains the preferred access site in a variety of cardiac, aortic, oncologic and peripheral vascular procedures. Both transarterial and venous cannulation (for electrophysiology, intravenous laser ablation and central catheterisation) at the groin may result in potentially severe vascular access site complications (VASC). Furthermore, vascular and soft-tissue groin infections may develop after untreated VASC or secondarily to non-sterile injections for recreational drug use. VASC and groin infections require rapid diagnosis and appropriate treatment to avoid further, potentially devastating harm. Whereas in the past colour Doppler ultrasound was generally used, in recent years cardiologists, vascular surgeons and interventional radiologists increasingly rely on pelvic and femoral CT angiography. Despite drawbacks of ionising radiation and the need for intravenous contrast, multidetector CT rapidly and consistently provides a panoramic, comprehensive visualisation, which is crucial for correct choice between conservative, endovascular and surgical management. This paper aims to provide radiologists with an increased familiarity with iatrogenic and self-inflicted VASC and infections at the groin by presenting examples of haematomas, active bleeding, pseudoaneurysms, arterial occlusion, arterio-venous fistula, endovenous heat-induced thrombosis, septic thrombophlebitis, soft-tissue infections at the groin, and late sequelae of venous injuries.

Teaching Points

• Complications may develop after femoral arterial or venous access for interventional procedures.

• Arterial injuries include bleeding, pseudoaneurysm, occlusion, arteriovenous fistula, dissection.

• Endovenous heat-induced thrombosis is a specific form of iatrogenic venous complication.

• Iatrogenic infections include groin cellulitis, abscesses and septic thrombophlebitis.

• CT angiography reliably triages vascular access site complications and groin infections.

Complications of Intravenous Substance Use Disorders (SUDs): A Multimodality Pictorial Essay for Cardiothoracic Radiologists

With the growing substance use disorders epidemic in the United States, a wide range of complications may be seen in both the acute and chronic clinical setting. This article will use a multimodality approach to review complications of intravenous substance use that cardiothoracic radiologists are likely to encounter. Radiologists should be aware of these multisystem complications that can affect the cardiovascular, respiratory, and musculoskeletal systems in order to make an accurate and timely diagnosis, which can drastically alter the management of these patients.

Heroin Use Is Associated with Ruptured Saccular Aneurysms

While cocaine use is thought to be associated with aneurysmal rupture, it is not known whether heroin use increases the risk of rupture in patients with non-mycotic saccular aneurysms. Our goal was to investigate the association between heroin and cocaine use and the rupture of saccular non-mycotic aneurysms. The medical records of 4701 patients with 6411 intracranial aneurysms, including 1201 prospective patients, diagnosed at the Brigham and Women's Hospital and Massachusetts General Hospital between 1990 and 2016 were reviewed and analyzed. Patients were separated into ruptured and non-ruptured groups. Univariable and multivariable logistic regression analyses were performed to determine the association between heroin, cocaine, and methadone use and the presence of ruptured intracranial aneurysms. In multivariable analysis, current heroin use was significantly associated with rupture status (OR 3.23, 95% CI 1.33-7.83) whereas former heroin use (with and without methadone replacement therapy), and current and former cocaine use were not significantly associated with intracranial aneurysm rupture. In the present study, heroin rather than cocaine use is significantly associated with intracranial aneurysm rupture in patients with non-mycotic saccular cerebral aneurysms, emphasizing the possible role of heroin in the pathophysiology of aneurysm rupture and the importance of heroin cessation in patients harboring unruptured intracranial aneurysms.

Posterior Reversible Encephalopathy Syndrome With Spinal Cord Involvement in Children

We characterized a cohort of patients with posterior reversible encephalopathy syndrome with spinal cord involvement. We encountered 2 children and identified an additional 19 patients from the internet databases. Of the 21 patients analyzed, 8 were children. The mean peak systolic blood pressure in adults was significantly higher than in children (221.8 ± 14.3 vs 191.4 ± 31.3 mm Hg; P < .01). Regardless of age, the most common clinical symptom was headache (90%) and the least common clinical symptom was seizures (28%). Atypical neuroimaging was more common in children (63%) than in adults (8%). Abnormal cerebrospinal fluid results were frequently found in children (83%). All children recovered uneventfully, but 3 adults had sequelae. A broader clinicoradiologic spectrum makes the diagnosis of children more complex than in adults. Awareness of the atypical features with a meticulous management of hypertension is imperative to avoid unnecessary invasive workups and to achieve an uneventful recovery.

Posterior reversible leukoencephalopathy syndrome with spinal cord involvement in a 9-year-old girl

We report the youngest pediatric case of posterior reversible leukoencephalopathy syndrome confined to brainstem and spinal cord. At presentation bicytopenia, renal derangement, visual disturbances, magnetic resonance imaging findings, increased protein content, IgG index and cell count in the cerebrospinal fluid led us to extensive search for myelitis. She received a short course of steroid treatment. The final diagnosis was hypertension due to reflux nephropathy. Severe hypertension that exceeds the range of autoregulation in anterior spinal territory may result in spinal posterior reversible leukoencephalopathy syndrome. Clinicians should be aware of spinal posterior reversible leukoencephalopathy syndrome when cases have extensive lesions in the brainstem and spinal cord with none or minimal clinical findings, so called "clinical radiologic dissociation".

Toxic leukoencephalopathies, including drug, medication, environmental, and radiation-induced encephalopathic syndromes

Toxic leukoencephalopathies can be secondary to the exposure to a wide variety of exogenous agents, including cranial irradiation, chemotherapy, antiepileptic agents, drugs of abuse, and environmental toxins. There is no typical clinical picture, and patients can present with a wide array of signs and symptoms. Involvement of white matter is a key finding in this scenario, although in some circumstances other high metabolic areas of the central nervous system can also be affected. Magnetic resonance (MR) imaging usually discloses bilateral and symmetric white matter areas of hyperintense signal on T2-weighted and fluid-attenuated inversion recovery images, and signs of restricted diffusion are associated in the acute stage. In most cases, the changes are reversible, especially with prompt recognition of the disease and discontinuation of the noxious agent. Either the MR or clinical features may be similar to several nontoxic entities, such as demyelinating diseases, leukodystrophies, hepatic encephalopathy, vascular disease, hypoxic-ischemic states, and others. A high index of suspicion should be maintained whenever a patient presents recent onset of neurologic deficit, searching the risk of exposure to a neurotoxic agent. Getting to know the most frequent MR appearances and mechanisms of action of causative agents may help to make an early diagnosis and begin therapy, improving outcome. In this review, some of the most important causes of leukoencephalopathies are presented; as well as other 2 related conditions: strokelike migraine attacks after radiation therapy syndrome and reversible splenial lesions.

Secondary demyelination disorders and destruction of white matter

Demyelinating disorders of the central nervous system are characterized by the breakdown of myelin, with or without preservation of the associated axons. Primary demyelinating diseases typically involve loss of myelin with relative sparing of axons. Secondary demyelinating disorders represent a spectrum of white matter disease characterized by damage to neurons or axons with the resultant breakdown of myelin. The pathologic changes seen in secondary demyelinating disorders are varied, ranging from pure demyelination to necrosis with subsequent demyelination. Secondary demyelinating diseases are associated with a wide variety of conditions, including infections/vaccinations, nutritional/vitamin deficiencies, chemical agents, genetic abnormalities, and vascular insult.

Neuropathology of substance use disorders

Addictions to licit and illicit drugs are chronic relapsing brain disorders that affect circuits that regulate reward, motivation, memory, and decision-making. Drug-induced pathological changes in these brain regions are associated with characteristic enduring behaviors that continue despite adverse biopsychosocial consequences. Repeated exposure to these substances leads to egocentric behaviors that focus on obtaining the drug by any means and on taking the drug under adverse psychosocial and medical conditions. Addiction also includes craving for the substances and, in some cases, involvement in risky behaviors that can cause death. These patterns of behaviors are associated with specific cognitive disturbances and neuroimaging evidence for brain dysfunctions in a diverse population of drug addicts. Postmortem studies have also revealed significant biochemical and/or structural abnormalities in some addicted individuals. The present review provides a summary of the evidence that has accumulated over the past few years to implicate brain dysfunctions in the varied manifestations of drug addiction. We thus review data on cerebrovascular alterations, brain structural abnormalities, and postmortem studies of patients who abuse cannabis, cocaine, amphetamines, heroin, and "bath salts". We also discuss potential molecular, biochemical, and cellular bases for the varied clinical presentations of these patients. Elucidation of the biological bases of addiction will help to develop better therapeutic approaches to these patient populations.

Lesions masquerading as acute stroke

Rapid and accurate recognition of lesions masquerading as acute stroke is important. Any incorrect or delayed diagnosis of stroke mimics will not only increase the risk of being exposed to unnecessary and possibly dangerous interventional therapies, but will also delay proper treatment. In this article, written from a neuroradiologist's perspective, we classified these lesions masquerading as acute stroke into three groups: lesions that may have "normal imaging," lesions that are "symptom mimics" but on imaging clearly not a stroke, and lesions that are "symptom and imaging mimics" with imaging findings similar to stroke. We focused the review on neuroimaging findings of the latter two groups ending with a suggestion for a diagnostic approach in the form of an algorithm.

Multidetector computed tomography of spontaneous versus secondary pneumomediastinum in 89 patients: can multidetector computed tomography be used to reliably distinguish between the 2 entities?

PURPOSE

To analyze the multidetector computed tomography (MDCT) findings of spontaneous pneumomediastinum (PM) to determine whether MDCT can reliably differentiate spontaneous from secondary PM.

MATERIALS AND METHODS

A retrospective clinical and chest MDCT analysis of all patients diagnosed with spontaneous PM over an 8-year period was performed. Radiologic comparison was undertaken with patients diagnosed with secondary PM from a central airways defect, esophageal rupture, or recent intervention in the airway or esophagus. The Fisher exact test for independence was used to compare the different MDCT findings between the groups.

RESULTS

A total of 89 patients were analyzed, with 1 secondary PM patient being included in both esophageal and central airways subsets, as the patient had an esophageal balloon-assisted intubation. Thirty-four patients were diagnosed with spontaneous PM. Compared with 28 patients with secondary PM from esophageal pathology, spontaneous PM patients were more likely to have air in the anterior mediastinum (97% vs 61%, P<0.001) and pulmonary interstitial emphysema (57% vs 4%, P<0.001), and less likely to show subdiaphragmatic air (0% vs 32%, P<0.001), pleural effusions (9% vs 61%, P<0.001), and acute pulmonary airspace opacities (14% vs 50%, P=0.003). Similarly, compared with 28 patients with secondary PM from trachea and bronchi pathology, patients with spontaneous PM were more likely to have pulmonary interstitial emphysema (57% vs 25%, P=0.01), and were less likely to show subdiaphragmatic air (0% vs 25%, P=0.002), pleural effusions (9% vs 39%, P=0.005), and acute pulmonary airspace opacities (14% vs 43%, P=0.02).

CONCLUSION

Spontaneous PM is associated with a favorable clinical course, and it is possible to suggest this clinical diagnosis based on typical MDCT findings and clinical presentation.

Epidemic of illicit drug use, mechanisms of action/addiction and stroke as a health hazard

Drug abuse robs individuals of their jobs, their families, and their free will as they succumb to addiction; but may cost even more: a life of disability or even life lost due to stroke. Many illicit drugs have been linked to major cardiovascular events and other comorbidities, including cocaine, amphetamines, ecstasy, heroin, phencyclidine, lysergic acid diethylamide, and marijuana. This review focuses on available epidemiological data, mechanisms of action, particularly those leading to cerebrovascular events, and it is based on papers published in English in PubMed during 1950 through February 2011. Each drug's unique interactions with the brain and vasculature predispose even young, healthy people to ischemic or hemorrhagic stroke. Cocaine and amphetamines have the strongest association with stroke. However, the level of evidence firmly linking other drugs to stroke pathogenesis is weak. Large epidemiological studies and systematic evaluation of each drug's action on the brain and cardiovascular system are needed to reveal the full impact of drug use on the population.

Imaging of illicit drug use

Illicit drug abuse is a continuing menace of epidemic proportions associated with serious medical and social problems. Drug abuse can have a wide variety of presentations some of which can be life-threatening. The clinical diagnosis can be challenging as the history is usually limited or absent. Radiologists need to be familiar with varied imaging presentations and the related complications of illicit drug abuse to ensure correct diagnosis and appropriate timely treatment. This review will illustrate the imaging spectrum of illicit drug abuse involving several organ systems and also discuss the pathophysiological consequences of drug abuse.

The art and science of straight lines in radiology

OBJECTIVE

The purpose of this article is to review the physical basis for straight radiographic lines, identify the possible components that may form a straight line interface in the body, provide illustrative examples across multiple organ systems and modalities, and explore how the detection of these interfaces can support specific diagnoses.

CONCLUSION

Detection of a straight line interface can help the radiologist recognize otherwise difficult or subtle pathologic processes, and identification of its components can provide valuable clues to diagnosis.

Emergent neuroimaging of intracranial infection/inflammation

Infectious and inflammatory processes of the intracranial compartment often result in acute clinical presentations. The possible causes are legion. Clues to the diagnosis involve clinical presentation, laboratory analysis, and neuroimaging. This article reviews some of the salient factors in understanding intracranial infection/ inflammation, including pathophysiology and neuroimaging protocols/findings, and provides some examples and a few "pearls and pitfalls."

Involvement of the cervical cord and medulla in posterior reversible encephalopathy syndrome

The posterior reversible encephalopathy syndrome (PRES) is characterized by patchy cortical and subcortical lesions in the distribution of the posterior circulation. The lesions are classically reversible. This syndrome has multiple etiologies, most of which cause acute hypertension. We present a case of PRES with involvement of the medulla and cervical cord (apart from the typical parieto-occipital lesions)--an extremely rare imaging manifestation of PRES. It is important to recognize the imaging findings of PRES in spinal cord, and avoid misdiagnosis as myelitis by proper clinical correlation. Typically patients with myelitis have a profound neurodeficit, while patients with spinal manifestations of PRES are asymptomatic. Involvement of the cord in PRES has probably been an underrecognized entity as spinal imaging is not routinely performed in posterior reversible encephalopathy syndrome.

Hyperintensity of the basal ganglia and cortex on FLAIR and diffusion-weighted imaging: self-assessment module

The educational objectives for this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of the hyperintensity of the basal ganglia and cortex on FLAIR and diffusion-weighted imaging and the key imaging characteristics of various causes of the hyperintensity of the basal ganglia and cortex.

MR imaging findings of medulla oblongata involvement in posterior reversible encephalopathy syndrome secondary to hypertension

Although the combination of MR imaging findings and clinical evidence of hypertension may suggest the diagnosis of posterior reversible encephalopathy syndrome (PRES), MR imaging findings with only involvement of the medulla oblongata pose a diagnostic dilemma. In the cases presented here, we demonstrated MR imaging findings of a presumed brain stem (medulla oblongata) variant of PRES and emphasized the diagnostic value of diffusion-weighted imaging (DWI).

Cardiovascular complications of cocaine: imaging findings

Cocaine is the second most commonly abused illicit drug in the US and the most common one involved in emergency department visits, the majority of which are related to the cardiovascular system. Cardiovascular complications related with cocaine abuse include myocardial ischemia and infarction, myocarditis, hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic dissection, thrombosis, stroke and cerebral hemorrhage, and different forms of visceral ischemia, among others. In an era where cocaine use has reached epidemic proportions, it is necessary for the radiologist to understand the pathophysiology, clinical presentation, and imaging characteristics of its cardiovascular complications.