Hugo Cuellar

Neuroimaging in drug and substance abuse part II: Opioids and solvents

The central nervous system is one of the primary targets for the detrimental effects of drugs of abuse. Diagnostic imaging, especially MRI, plays an important role in the detection of complications associated with drug abuse. We present the imaging findings associated with the abuse of opioids and other morphine derivatives, as well, as solvents. Of the morphine derivatives, heroin is the most commonly abused. Several CNS pathologic effects have been described in association with its abuse. These include neurovascular complications such as microvascular ischemic changes or ischemic stroke. A rare form of leukoencephalopathy has been described in those abusers who inhale heroin vapors. Other neurologic complications include atrophy and various infectious processes. Solvent inhalation is a common practice among adolescents and young adults secondary to its ease of access and low cost. The most important component of industrial solvents is toluene. Complications of toluene abuse may be either acute, showing no neuroradiological changes, or chronic, characterized by cerebral and cerebellar demyelination as well as atrophy.

Fatal methadone intoxication in a child

Methadone is an opiate used as part of the treatment for heroin abuse; it can be ingested orally. We present the lethal outcome of a 22-month-old child intoxicated after methadone ingestion.

Neuroimaging in drug and substance abuse part I: Cocaine, cannabis, and ecstasy

Multiple neurological complications of cocaine abuse have been described including both ischemic and hemorrhagic cerebrovascular events, atrophy in the case of chronic abuse, and an increase in incidence of congenital malformations in the setting of maternal use. The abuse of cannabis may cause a number of neurovascular changes that, in turn, may result in ischemic events, however, a direct connection between these has not been fully established. The use of MDMA (ecstasy), a popular recreational drug, has been related to ischemic and hemorrhagic cerebrovascular events, as well as atrophy. Neuroimaging studies are vital in the assessment of the extent of neurologic damage in these patients.

Balloon-assisted extrasaccular coil embolization technique for the treatment of very small cerebral aneurysms.

Treatment of very small ruptured cerebral aneurysms (< 2 mm) continues to present a challenge. These lesions are difficult to treat both with neurosurgical and endovascular techniques. A neurosurgical approach is still the treatment of choice for these lesions at many centers because of high rupture rates related to endovascular treatment; however, there are clinical circumstances in which the neurosurgical option cannot be offered. In their review of the literature, the authors did not find any series reporting endovascular treatment of these very small aneurysms. In the present study, the authors report their experience with the endovascular treatment of a series of 4 ruptured aneurysms smaller than 2 mm from neck to dome. They describe their technique of using a remodelling balloon to stabilize the tip of the microcatheter in the neck of the aneurysm without entering it at any time, and of inserting the coil from outside the sac to minimize the risk of intraoperative rupture, which is very high when conventional endovascular embolization is performed.

Successful Treatment of Iatrogenic Vertebral Pseudoaneurysm Using Pipeline Embolization Device

Traumatic pseudoaneurysms are uncommon and one of the most difficult lesions to treat. Traditional treatment methods have focused on parent vessel sacrifice with or without revascularization. We report the case of a patient who underwent successful treatment of an iatrogenic extracranial vertebral artery pseudoaneurysm using the Pipeline Embolization Device. A 47-year-old man sustained an inadvertent injury to the left vertebral artery during C1-C2 fixation. Subsequent imaging revealed an iatrogenic vertebral artery pseudoaneurysm. Immediate angiogram was normal. A repeat angiogram done after 3 days of the surgery revealed a vertebral artery pseudoaneurysm. He underwent aneurysm exclusion and vascular reconstruction using the Pipeline Embolization Device. Although flow-diverting stents are currently not being used for treating traumatic pseudoaneurysms, their use may be considered in such cases if active bleeding has ceased. In our case, the patient did well and the aneurysm was excluded from circulation while reconstructing the vessel wall.

Treatment of a carotid cavernous fistula via direct transovale cavernous sinus puncture.

Endovascular treatment is the treatment of choice for indirect carotid cavernous fistulas (CCFs). Direct surgical obliteration of CCFs is recommended in highly symptomatic patients or in those with an aggressive pattern of venous drainage. However, this is a technically challenging approach associated with significant procedural morbidity. The authors present a case in which they decided to attempt a novel access to the cavernous sinus through the foramen ovale before recommending surgery for an otherwise untreatable dural CCF. This 52-year-old man with an indirect CCF and neurological deficit had undergone several attempts to embolize the shunt by means of the standard approaches. Ultimately direct cavernous sinus access was obtained through the foramen ovale, resulting in complete obliteration of the shunt. The occlusion was radiographically stable at the 6-month follow-up evaluation, and the patient has remained asymptomatic. Percutaneous transovale puncture of a CCF is a feasible alternative to accessing the cavernous sinus when traditional transvenous catheterization or direct superior ophthalmic vein approach is not possible.

Anatomical results, rebleeding and factors that affect the degree of occlusion in ruptured cerebral aneurysms after endovascular therapy

Object To present a series of ruptured cerebral aneurysms in consecutive non-selected patients treated with endovascular therapy, analyzing the initial degree of occlusion, its anatomical evolution mid-term and the variables that could statistically affect them. Methods 251 aneurysms were first treated with coiling (embolization). 203 patients were followed up with conventional angiography for 6–8 months after the initial treatment and 182 were followed up with three-dimensional time of flight MR angiography at18–24 months. Postoperative and mid-term anatomical results were evaluated anonymously and independently using the modified Montreal Scale. Results The initial rate of complete occlusion was 70.9%, with rates of neck remnants and aneurysm remants of 18.3% and 10.7%, respectively. The recurrence rate was 13% after 6 months and 2% between 6 months and 2 years. The rate of retreatment was 11%. Statistically, the variables that were found to be related to the initial degree of occlusion were the use of a remodeling balloon technique (p=0.012), the size of the aneurysm neck (p=0.044) and the size of the aneurysm (p=0.004). The recanalization rate at mid-term depended on the size of the aneurysm. Although aneurysms with partial occlusion initially tended to evolve to a worse degree of closure than those with complete occlusion initially, the relationship was not statistically significant (p=0.110). Conclusions Embolized aneurysms can develop a worse degree of closure even when the initial occlusion is complete. The degree of occlusion depends directly on morphological factors and the use of balloon-assisted techniques. The recanalization rate at mid-term depends on the size of the aneurysm and probably on the density of the packing achieved with the initial treatment.

Pet and Spect in Drug and Substance Abuse

The use of imaging in the evaluation of the brain under the influence of drugs has evolved into a functional assessment of its processes. It has been shown that SPECT and PET imaging studies demonstrate selected areas that are affected by multiple drugs among substance abusers. This paper illustrates examples of different drugs and how their effect on the brain may be portrayed by imaging applications. The developing “road maps” that we have obtained possess multidimensional applications. They can be useful to confirm specific diseases, clarify diagnosis wherein the clinical picture is not observed, aid in the development of new treatment evaluations and also provide researchers a better insight in the detection and functionality of dementia and specific mental illnesses processes.

158 Morphological Parameters for Anterior Communicating Artery Aneurysm Rupture Risk Assessment.

INTRODUCTION Several demographic, morphological, and hemodynamic factors influence the rupture of an intracranial aneurysm. The authors aim to investigate whether the morphological factors of an aneurysm in anterior communicating artery (ACOM Art) influence the rupture. METHODS Several 1-dimensional, 2-dimensional, and 3-dimensional parameters were evaluated in 3D digital subtraction angiography. The measurements were performed in blinded fashion to determine whether the size and shape parameters influence the rupture. A total of 30 anterior communicating aneurysms (ruptured = 15 and unruptured = 15) were taken for analysis. Five 1-dimensional factors such as diameter of neck, maximum width of aneurysm, maximum height of the aneurysm, and maximum perpendicular height of aneurysm and parent artery diameter were calculated. Two dimensional factors such as aspect ratio, size ratio, aneurysm angle, vessel angle, flow angle, parent daughter angle, and bottleneck factor were estimated. Three-dimensional parameters such as conicity index were also calculated. A pictorial representation of method of calculation has been depicted below. The standard demographic risk factors such as female sex, hypertension, and smoking were also considered to match the 2 groups. Two-tailed independent student t tests were used to determine the statistical difference between the morphological indices. Area under curve (AUC) was estimated in the receiver operating characteristic (ROC) curve for risk assessment analysis. RESULTS Standard size and shape parameters are poor determinants of rupture of an ACOM Art aneurysm. The parent daughter angle (0.67), aspect ratio (0.56), bottle neck factor (0.55), and conicity index (0.44) were found to be the most significant factors in ROC curve analysis. However, the strength of association remains poor for each of them. CONCLUSION Standard morphometric parameters are not good predictors of rupture of ACOM Art aneurysms. Multifactorial analysis including complex shape indices along with hemodynamic parameters are required to determine the rupture risk.

Asymptomatic Delayed Coil Migration from an Intracranial Aneurysm: A Case Report

Objective. To describe asymptomatic delayed migration of a coil loop in a patient following successful coil embolization of an anterior communicating artery saccular aneurysm. Methods. A 24-year-old man with a ruptured anterior communicating artery saccular aneurysm underwent coil embolization with one helical ultrasoft coil. Results. A followup CT scan head and a cerebral angiogram one month following the procedure revealed distal migration of an intra-aneurysmal coil loop into the left pericallosal artery. The patient, however, remained asymptomatic. Conclusion. Delayed migration of coil following embolization of an intracranial aneurysm is an extremely rare occurrence. An asymptomatic presentation, as in our patient, is even more unique. The stent-like configuration of the migrated spiral coil loop probably prevented complete occlusion of the blood vessel.