Peri-lead edema after deep brain stimulation surgery for Parkinson's disease: a prospective magnetic resonance imaging study.

BACKGROUND AND PURPOSE: The aim of this study was to define the prevalence and characteristics of peri-electrode edema in a prospective cohort of patients undergoing deep brain stimulation (DBS) surgery and to correlate it with clinical findings. METHODS: We performed brain magnetic resonance imaging (MRI) between 7 and 20 days after surgery in 19 consecutive patients undergoing DBS surgery for Parkinson's disease. The T2-weighted hyperintensity surrounding DBS leads was characterized and quantified. Any evidence of bleeding around the leads was also evaluated. Clinical and follow-up data were recorded. In a subgroup of patients, a follow-up MRI was performed 3-6 weeks after surgery. We also retrospectively reviewed the post-operative computed tomography scans of patients who underwent DBS at our center since 2013. RESULTS: Magnetic resonance imaging showed a peri-lead edematous reaction in all (100%) patients, which was unilateral in three patients (15.8%). In six patients (31.6%), we detected minor peri-lead hemorrhage. Edema completely resolved in eight out of 11 patients with a follow-up MRI and was markedly reduced in the others. Most patients were asymptomatic but six (31.6%) manifested various degrees of confusional state without motor symptoms. We found no significant correlation between edema volume, distribution and any clinical feature, including new post-operative neurological symptoms. The retrospective computed tomography analysis showed that peri-electrode hypodensity consistent with edema is absent at early post-operative imaging but is common at scans performed >3 days after surgery. CONCLUSIONS: Peri-electrode edema is a common, transient reaction to DBS lead placement and a convincing relation between edema and post-operative clinical status is lacking.

Ultrasound-tagged near-infrared spectroscopy does not disclose absent cerebral circulation in brain-dead adults.

BACKGROUND: Near-infrared spectroscopy, a non-invasive technique for monitoring cerebral oxygenation, is widely used, but its accuracy is questioned because of the possibility of extra-cranial contamination. Ultrasound-tagged near-infrared spectroscopy (UT-NIRS) has been proposed as an improvement over previous methods. We investigated UT-NIRS in healthy volunteers and in brain-dead patients. METHODS: We studied 20 healthy volunteers and 20 brain-dead patients with two UT-NIRS devices, CerOx™ and c-FLOW™ (Ornim Medical, Kfar Saba, Israel), which measure cerebral flow index (CFI), a parameter related to changes in cerebral blood flow (CBF). Monitoring started after the patients had been declared brain dead for a median of 34 (range: 11-300) min. In 11 cases, we obtained further demonstration of absent CBF. RESULTS: In healthy volunteers, CFI was markedly different in the two hemispheres in the same subject, with wide variability amongst subjects. In brain-dead patients (median age: 64 yr old, 45% female; 20% traumatic brain injury, 40% subarachnoid haemorrhage, and 40% intracranial haemorrhage), the median (inter-quartile range) CFI was 41 (36-47), significantly higher than in volunteers (33; 27-36). CONCLUSIONS: In brain-dead patients, where CBF is absent, the UT-NIRS findings can indicate an apparently perfused brain. This might reflect an insufficient separation of signals from extra-cranial structures from a genuine appraisal of cerebral perfusion. For non-invasive assessment of CBF-related parameters, the near-infrared spectroscopy still needs substantial improvement.

Craniofacial structures' development in prenatal period: An MRI study.

INTRODUCTION: The development of skeletal structures (cranial base, upper and lower) and upper airways spaces (oropharyngeal and nasopharyngeal) of the skull has always been an issue of great interest in orthodontics. Foetal MRI images obtained as screening exam during pregnancy can help to understand the development of these structures using a sample cephalometric analysis. MATERIAL AND METHODS: A total of 28 MRI images in sagittal section of foetuses from 20th to 32th weeks of gestation were obtained to dispel doubts about the presence of skeletal malformations. Cephalometric measurements were performed on MRI T2-dependent images acquired with a 1.5 T scanner. The Software Osirix 5 permits to study sagittal and vertical dimensions of the skull analysing linear measurements, angles and areas of the skeletal structures. RESULTS: Vertical and sagittal dimension of cranial base, maxilla and mandible grow significantly (P < .01) between the second and third trimester of gestational period as well as nasopharyngeal and oropharyngeal spaces (P < .05). High correlation between the development of anterior cranial base and functional areas devoted to speech and swallow is demonstrated (r: .97). CONCLUSIONS: The development of craniofacial structures during foetal period seems to show a close correlation between skeletal features and functional spaces with a peak between the second and third trimester of gestation. MRI images result helpful for the clinician to detect with a sample cephalometric analysis anomalies of skeletal and functional structures during prenatal period.

Fetal magnetic resonance imaging: indications, study protocols and safety.

The aim of this paper is to outline the real indications for fetal magnetic resonance imaging (FMRI) based on the current clinical and scientific evidence and to determine where it fits into prenatal diagnostic protocols. We also consider the most commonly used FMRI diagnostic protocols and take stock of the safety aspects of this examination. This paper is the result of the work of the Fetal Magnetic Resonance (FMR) Study Group of the Italian Society of Medical Radiology (SIRM) in cooperation with the Study Group of the Italian Society of Ultrasound in Obstetrics and Gynaecology (SIEOG). It has been reviewed and approved by the Italian Association of Neuroradiology (AINR). As FMRI is undergoing continuous development, and its indications and role are also likely to change over time, the Fetal Magnetic Resonance Study Group is in agreement with the other scientific bodies involved in the drafting of this document to propose subsequent modifications to it when new clinical and scientific evidence suggest the need.

Ganglionic Eminence Anomalies and Coexisting Cerebral Developmental Anomalies on Fetal MR Imaging: Multicenter-Based Review of 60 Cases.

BACKGROUND AND PURPOSE: The ganglionic eminences are transient fetal brain structures that produce a range of neuron types. Ganglionic eminence anomalies have been recognized on fetal MR imaging and anecdotally found in association with a number of neurodevelopmental anomalies. The aim of this exploratory study was to describe and analyze the associations between ganglionic eminence anomalies and coexisting neurodevelopmental anomalies. MATERIALS AND METHODS: This retrospective study includes cases of ganglionic eminence anomalies diagnosed on fetal MR imaging during a 20-year period from 7 centers in Italy and England. Inclusion criteria were cavitation or increased volume of ganglionic eminences on fetal MR imaging. The studies were analyzed for associated cerebral developmental anomalies: abnormal head size and ventriculomegaly, reduced opercularization or gyration, and abnormal transient layering of the developing brain mantle. The results were analyzed using χ2 and Fisher exact tests. RESULTS: Sixty fetuses met the inclusion criteria (21 females, 24 males, 15 sex unknown). Thirty-four had ganglionic eminence cavitations (29 bilateral and 5 unilateral), and 26 had increased volume of the ganglionic eminences (19 bilateral, 7 unilateral). Bilateral ganglionic eminence cavitations were associated with microcephaly (P = .01), reduced opercularization, (P < .001), reduced gyration (P < .001), and cerebellar anomalies (P = .01). Unilateral ganglionic eminence cavitations were not significantly associated with any particular feature. Bilateral increased volume of the ganglionic eminences showed an association with macrocephaly (P = .03). Unilateral increased volume was associated with macrocephaly (P = .002), abnormal transient layering (P = .001), unilateral polymicrogyria (P = .001), and hemimegalencephaly (P < .001). CONCLUSIONS: Ganglionic eminence anomalies are associated with specific neurodevelopmental anomalies with ganglionic eminence cavitations and increased ganglionic eminence volume apparently having different associated abnormalities.

Assessment of the Membranous Labyrinth in Infants Using a Heavily T2-weighted 3D FLAIR Sequence without Contrast Agent Administration.

BACKGROUND AND PURPOSE: Imaging is fundamental to assessing the acoustic pathway in infants with congenital deafness. We describe our depiction of the membranous labyrinth in infants using the heavily T2-weighted 3D FLAIR sequence without a contrast agent. MATERIALS AND METHODS: We retrospectively reviewed 10 infants (20 ears) (median term equivalent age: 2 weeks; IQR: 1-5 weeks) who had undergone brain MR imaging including a noncontrast heavily T2-weighted 3D FLAIR scan of the temporal bone. For each ear, 3 observers analyzed, in consensus, the saccule, the utricle, and the 3 ampullae, assessing the visibility (score 0, not appreciable; score 1, visible without well-defined boundaries; score 2, visible with well-defined boundaries) and morphology ("expected" or "unexpected" compared with adults). The heavily T2-weighted 3D FLAIR sequence was scored for overall quality (score 0, inadequate; score 1, adequate but with the presence of image degradation; score 2, adequate). RESULTS: Six (60%) MR examinations were considered adequate (score 1 or 2). The saccule was visible in 10 ears (83.3%) with an expected morphology in 9 ears (90%). In 1 ear of an infant with congenital deafness, the saccule showed an unexpected morphology. The utricle was visible as expected in 12 ears (100%). The lateral ampulla was visible in 5 ears (41.6%), the superior ampulla was visible in 6 ears (50.0%), and the posterior ampulla was visible in 6 ears (50.0%), always with expected morphology (100%). CONCLUSIONS: MR imaging can depict the membranous labyrinth in infants using heavily T2-weighted 3D FLAIR without an injected contrast agent, but the sequence acquisition time reduces its feasibility in infants undergoing MR studies during natural sleep.

Diagnostic imaging of the pediatric nasal cavity and paranasal sinuses.

The vast majority of nasal and paranasal sinuses (PNS) diseases in childhood are of inflammatory origin. In particular, during the early rapid development of PNS rhinosinusitis are exceedingly frequent in both acute and chronic forms. However other diseases such as primarily congenital malformation, but also neoplasms can affect the nasal cavity (NC) and PNS during pediatric age. Modern radiological techniques such as multidetector computerized tomography (MDCT) or magnetic resonance imaging (MRI) are becoming of greater importance in the diagnosis of chronic or complicated inflammatory processes of NC and PNS and in the differential diagnosis with the other less frequent diseases. The characteristic features of MDCT and MRI and their diagnostic role in the more frequent pediatric inflammatory, neoplastic and congenital diseases of NC and PNS are reviewed.

Imaging criteria for diagnosis of chronic rhinosinusitis in children.

Symptoms of chronic rhinosinusitis (CRS) are nasal blockage, nasal discharge, postnasal drip, facial pain, headache, and reduction or loss of smell, but they are often subtle and make it difficult to obtain a firm diagnosis based only on clinical data, and especially to distinguish CRS from persistent rhinitis. A diagnosis of certainty of CRS relies upon either direct observation by nasal fibroendoscopy of nasal turbinates, middle meatus, and rhinopharynx, detecting mucopurulent discharge from the middle meatus, and/or oedema or mucosal obstruction, or by imaging of the rhinosinusal cavities. Imaging techniques such as computed tomography (CT) scanning and magnetic resonance (MR) are currently recommended in consensus documents, while plain radiography is considered of poor diagnostic value. However, recent studies indicated that radiography by the Waters'projection had a sensitivity of 84.2% and a specificity of 76.6%, which suggests to use it routinely in suspected CRS, limiting the number of more expensive imaging investigations. This seems important in the current economic landscape that requires a cost-effectiveness evaluation in each diagnostic procedure.

COVID-19-Associated PRES-like Encephalopathy with Perivascular Gadolinium Enhancement.

We describe the case of a 63-year-old woman who developed a coronavirus disease 2019-associated acute encephalopathy with perivascular gadolinium enhancement.

Reappraising the role of radiography in the diagnosis of chronic rhinosinusitis.

OBJECTIVE: To revaluate the role of radiography in the diagnosis of chronic rhinosinutis, versus the currently suggested standards of computed tomography (CT) or nasal endoscopy. MATERIALS AND METHODS: In total, 269 children consecutively admitted to our Unit for symptoms suggestive of chronic rhinosinusitis were included in this study; of these 222 were confirmed by fiberoptic nasopharyngeal endoscopy to have chronic rhinosinusitis, while 47 were not. Analysis of sensitivity and specificity of plain radiography by Waters' projection was carried. RESULTS: Radiography had a sensitivity of 84.2% (95% confidence interval 78.8 to 88.8), and a specificity of 76.6% (95% confidence interval 62.0 to 87.7) against the standard of nasal endoscopy. CONCLUSIONS: In routine practice, the clinical diagnosis of chronic rhinosinusitis may be obtained in many cases by Waters' projection radiography, limiting more expensive CT scanning or endoscopic techniques, which remain the reference diagnostic tools, to a smaller number of patients.

Safety and Diagnostic Efficacy of Gadobenate Dimeglumine in MRI of the Brain and Spine of Neonates and Infants.

BACKGROUND AND PURPOSE: Contrast-enhanced MR imaging provides essential information for pediatric imaging applications. We evaluated gadobenate dimeglumine for contrast-enhanced MR imaging of infants younger than 2 years of age. MATERIALS AND METHODS: Ninety children younger than 2 years of age (including 55 children younger than 1 year) who underwent enhanced MR imaging of the CNS with gadobenate dimeglumine at 0.1 mmol/kg body weight ± 25% by volume were retrospectively enrolled at 2 imaging centers. Safety data were assessed for adverse events and, when available, vital signs and electrocardiogram and clinical laboratory values obtained from 48 hours before until 48 hours after the MR imaging examination. The efficacy of gadobenate dimeglumine-enhanced MR imaging was evaluated prospectively by 3 blinded, unaffiliated readers in terms of the accuracy of combined pre- and postcontrast images relative to precontrast images alone for differentiation of tumor from non-neoplastic disease and the correct diagnosis of specific disease. Differences were tested using the McNemar test. A possible effect of dose on diagnostic accuracy was assessed using the Fisher exact test. RESULTS: Nine nonserious adverse events were reported for 8 (8.8%) patients. Five adverse events occurred in patients 12 months of age or older. All events occurred at least 24 hours after gadobenate dimeglumine administration, and in each case, the investigating radiologist considered that there was no reasonable possibility of a relationship to gadobenate dimeglumine. No clinically meaningful changes in vital signs, electrocardiogram results, or laboratory parameters were reported. Accurate differentiation of tumor from non-neoplastic disease and exact matching of each specific MR imaging-determined diagnosis with the on-site final diagnosis were achieved in significantly more patients by each reader following evaluation of combined pre- and postcontrast images relative to precontrast images alone (91.0%-94.4% versus 75.3%-87.6%, P < .04, and 66.3%-73.0% versus 52.8%-58.4%, P < .02, respectively). No significant differences (P > .133) in diagnostic accuracy were noted between patients receiving ≤0.08 mmol/kg of gadobenate dimeglumine and patients receiving >0.08 mmol/kg of gadobenate dimeglumine. CONCLUSIONS: Gadobenate dimeglumine is safe and effective for pediatric MR imaging.

Brain DSC MR Perfusion in Children: A Clinical Feasibility Study Using Different Technical Standards of Contrast Administration.

BACKGROUND AND PURPOSE: Dynamic susceptibility contrast MR perfusion imaging has limited results in children due to difficulties in reproducing technical standards derived from adults. This prospective, multicenter study aimed to determine DSC feasibility and quality in children using custom administration of a standard dose of gadolinium. MATERIALS AND METHODS: Eighty-three consecutive children with brain tumors underwent DSC perfusion with a standard dose of gadobutrol administered by an automated power injector. The location and size of intravenous catheters and gadobutrol volume and flow rates were reported, and local and/or systemic adverse effects were recorded. DSC was qualitatively evaluated by CBV maps and signal intensity-time curves and quantitatively by the percentage of signal drop and full width at half-maximum, and the data were compared with the standards reported for adults. Quantitative data were grouped by flow rate, and differences among groups were assessed by analysis of covariance and tested for statistical significance with a t test. RESULTS: No local or systemic adverse events were recorded independent of catheter location (63 arm, 14 hand, 6 foot), size (24-18 ga), and flow rates (1-5 mL/s). High-quality CBV maps and signal intensity-time curves were achieved in all patients, and quantitative evaluations were equal or superior to those reported for adults. No significant differences (P ≥ .05) were identified among the higher-flow-rate groups in the quantitative data. CONCLUSIONS: A custom administration of a standard dose of gadobutrol allows safe and high-quality DSC MR perfusion imaging in children.

MR imaging of endolymphatic hydrops in Ménière's disease: not all that glitters is gold.

Ménière's disease (MD) is a chronic condition characterised by fluctuating hearing loss, intermittent vertigo, tinnitus and aural fullness. Its anatomical and pathological counterpart is represented by endolymphatic hydrops (EH). Recent development and progress in magnetic resonance (MR) imaging techniques has enabled visualisation of EH in living human subjects using a 3 Tesla (T) scanner and gadolinium-based contrast-agent (GBCA) via intravenous (IV) or intra-tympanic (IT) administration. Data emerging from the literature about MR imaging of EH in MD patients are limited, and we therefore reviewed the most common MR imaging findings in the study of the endolymphatic space in both MD and non-MD patients.

Multiparametric MR imaging of Parkinsonisms at 3 tesla: Its role in the differentiation of idiopathic Parkinson's disease versus atypical Parkinsonian disorders.

OBJECTIVES: The Nigrosome-1 and putaminal hypointensity depicted on susceptibility-weighted imaging (SWI), and midbrain atrophy assessed on T1-weighted are some of the most common radiological parameters to diagnose Parkinsonism at Magnetic Resonance (MR) imaging. Our aim is to assess the feasibility of these signs in the differentiation of Idiopathic Parkinson's disease (IPD) patients versus disease (DC) and healthy controls (HC) and in the assessment of the Atypical Progressive Parkinsonisms (APPs). METHODS: Presence or loss of the Nigrosome-1 was assessed retrospectively on multiple-echo SWI obtained on a 3 T scan by two neuroradiologists. Results were compared with the 123I-FP-CIT SPECT images. Morphologic diagnostic features suggestive of APPs such as midbrain atrophy and putaminal hypointensity were evaluated by qualitative scores. The midbrain and putaminal scores were summed (combined score) and then added to the Nigrosome-1 score (global score). RESULTS: The study included 126 patients with IPD (n = 56), APPs patients (n = 30; 18 PSP, 3 MSA-C, 9 MSA-P), 16 DC and 24 HC. Sensitivity and specificity of the Nigrosome-1 in discriminating IPD from controls were 96,43% and 85.00%, APPs from controls were 100% and 85%, IPD from APPs were 96,43% and 0% respectively. Combined score for midbrain atrophy and putaminal hypointensity resulted in the most accurate for distinguishing APPs from IPD with a value of ≥ 2 (AUC = 0.98). CONCLUSION: Nigrosome-1 is a valid tool to differentiate IPD-APPs from controls. The combined score of midbrain atrophy and putaminal hypointensity represents a valid diagnostic pointer in the differential diagnosis of APPs from IPD.

MR Imaging in Menière Disease: Is the Contact between the Vestibular Endolymphatic Space and the Oval Window a Reliable Biomarker?

BACKGROUND AND PURPOSE: No reliable MR imaging marker for the diagnosis of Menière disease has been reported. Our aim was to investigate whether the obliteration of the inferior portion of the vestibule and the contact with the stapes footplate by the vestibular endolymphatic space are reliable MR imaging markers in the diagnosis of Menière disease. MATERIALS AND METHODS: We retrospectively enrolled 49 patients, 24 affected by unilateral sudden hearing loss and 25 affected by definite Menière disease, who had undergone a 4-hour delayed 3D-FLAIR sequence. Two readers analyzed the MR images investigating whether the vestibular endolymphatic space bulged in the third inferior portion of the vestibule contacting the stapes footplate. This sign was defined as the vestibular endolymphatic space contacting the oval window. RESULTS: We analyzed 98 ears: 27 affected by Menière disease, 24 affected by sudden sensorineural hearing loss, and 47 that were healthy. The vestibular endolymphatic space contacting the oval window showed an almost perfect interobserver agreement (Cohen κ = 0.87; 95% CI, 0.69-1). The vestibular endolymphatic space contacting oval window showed the following: sensitivity = 81%, specificity = 96%, positive predictive value = 88%, and negative predictive value = 93% in differentiating Menière disease ears from other ears. The vestibular endolymphatic space contacting the oval window showed the following: sensitivity = 81%, specificity = 96%, positive predictive value = 96%, negative predictive value = 82% in differentiating Menière disease ears from sudden sensorineural hearing loss ears. CONCLUSIONS: The vestibular endolymphatic space contacting the oval window has high specificity and positive predictive value in differentiating Menière disease ears from other ears, thus resulting in a valid tool for ruling in Menière disease in patients with mimicking symptoms.

Prenatal Brain MR Imaging: Reference Linear Biometric Centiles between 20 and 24 Gestational Weeks.

BACKGROUND AND PURPOSE: Evaluation of biometry is a fundamental step in prenatal brain MR imaging. While different studies have reported reference centiles for MR imaging biometric data of fetuses in the late second and third trimesters of gestation, no one has reported them in fetuses in the early second trimester. We report centiles of normal MR imaging linear biometric data of a large cohort of fetal brains within 24 weeks of gestation. MATERIALS AND METHODS: From the data bases of 2 referral centers of fetal medicine, accounting for 3850 examinations, we retrospectively collected 169 prenatal brain MR imaging examinations of singleton pregnancies, between 20 and 24 weeks of gestational age, with normal brain anatomy at MR imaging and normal postnatal neurologic development. To trace the reference centiles, we used the CG-LMS method. RESULTS: Reference biometric centiles for the developing structures of the cerebrum, cerebellum, brain stem, and theca were obtained. The overall interassessor agreement was adequate for all measurements. CONCLUSIONS: Reference biometric centiles of the brain structures in fetuses between 20 and 24 weeks of gestational age may be a reliable tool in assessing fetal brain development.

Anterior Mesencephalic Cap Dysplasia: Novel Brain Stem Malformative Features Associated with Joubert Syndrome.

In Joubert syndrome, the "molar tooth" sign can be associated with several additional supra- and infratentorial malformations. Here we report on 3 subjects (2 siblings, 8-14 years of age) with Joubert syndrome, showing an abnormal thick bulging of the anterior profile of the mesencephalon causing a complete obliteration of the interpeduncular fossa. DTI revealed that the abnormal tissue consisted of an ectopic white matter tract with a laterolateral transverse orientation. Tractographic reconstructions support the hypothesis of impaired axonal guidance mechanisms responsible for the malformation. The 2 siblings were compound heterozygous for 2 missense variants in the TMEM67 gene, while no mutations in a panel of 120 ciliary genes were detected in the third patient. The name "anterior mesencephalic cap dysplasia," referring to the peculiar aspect of the mesencephalon on sagittal MR imaging, is proposed for this new malformative feature.

Flat Panel Angiography in the Cross-Sectional Imaging of the Temporal Bone: Assessment of Image Quality and Radiation Dose Compared with a 64-Section Multisection CT Scanner.

BACKGROUND AND PURPOSE: Cross-sectional imaging of the temporal bone is challenging because of the complexity and small dimensions of the anatomic structures. We evaluated the role of flat panel angiography in the cross-sectional imaging of the temporal bone by comparing its image quality and radiation dose with a 64-section multisection CT scanner. MATERIALS AND METHODS: We retrospectively collected 29 multisection CT and 29 flat panel angiography images of normal whole-head temporal bones. Image quality was assessed by 2 neuroradiologists, who rated the visualization of 30 anatomic structures with a 3-point ordinal scale. The radiation dose was assessed with an anthropomorphic phantom. RESULTS: Flat panel angiography showed better image quality than multisection CT in depicting the anterior and posterior crura of the stapes, the footplate of the stapes, the stapedius muscle, and the anterior ligament of the malleus (P < .05). In contrast, multisection CT showed better image quality than flat panel angiography in assessing the tympanic membrane, the bone marrow of the malleus and incus, the tendon of the tensor tympani, the interscalar septum, and the modiolus of the cochlea (P < .05). Flat panel angiography had a significantly higher overall image quality rating than multisection CT (P = .035). A reduction of the effective dose of approximately 40% was demonstrated for flat panel angiography compared with multisection CT. CONCLUSIONS: Flat panel angiography shows strengths and weaknesses compared with multisection CT. It is more susceptible to artifacts, but due to the higher spatial resolution, it shows equal or higher image quality in assessing some bony structures of diagnostic interest. The lower radiation dose is an additional advantage of flat panel angiography.

MR Imaging in Sudden Sensorineural Hearing Loss. Time to Talk.

Sudden sensorineural hearing loss is defined as acute hearing loss of the sensorineural type of at least 30 dB over 3 contiguous frequencies that occurs within a 72-hour period. Although many different causative factors have been proposed, sudden sensorineural hearing loss is still considered "idiopathic" in 71%-85% of cases, and treatments are empiric, not based on etiology. MR imaging implemented with a 3D FLAIR sequence has provided new insights into the etiology of sudden sensorineural hearing loss. Herein, we review the current management trends for patients with sudden sensorineural hearing loss, from the initial clinical diagnosis to therapeutic strategies and diagnostic work-up. We focused primarily on MR imaging assessment and discuss the relevance that MR imaging findings might have for patient management, pointing out different perspectives for future clinical research.

Structural and metabolic differentiation between bipolar disorder with psychosis and substance-induced psychosis: An integrated MRI/PET study.

BACKGROUND: Bipolar disorder (BD) may be characterized by the presence of psychotic symptoms and comorbid substance abuse. In this context, structural and metabolic dysfunctions have been reported in both BD with psychosis and addiction, separately. In this study, we aimed at identifying neural substrates differentiating psychotic BD, with or without substance abuse, versus substance-induced psychosis (SIP) by coupling, for the first time, magnetic resonance imaging (MRI) and positron emission tomography (PET). METHODS: Twenty-seven BD type I psychotic patients with (n=10) or without (n=17) substance abuse, 16 SIP patients and 54 healthy controls were enrolled in this study. 3T MRI and 18-FDG-PET scanning were acquired. RESULTS: Gray matter (GM) volume and cerebral metabolism reductions in temporal cortices were observed in all patients compared to healthy controls. Moreover, a distinct pattern of fronto-limbic alterations were found in patients with substance abuse. Specifically, BD patients with substance abuse showed volume reductions in ventrolateral prefrontal cortex, anterior cingulate, insula and thalamus, whereas SIP patients in dorsolateral prefrontal cortex and posterior cingulate. Common alterations in cerebellum, parahippocampus and posterior cingulate were found in both BD with substance abuse and SIP. Finally, a unique pattern of GM volumes reduction, with concomitant increased of striatal metabolism, were observed in SIP patients. CONCLUSIONS: These findings contribute to shed light on the identification of common and distinct neural markers associated with bipolar psychosis and substance abuse. Future longitudinal studies should explore the effect of single substances of abuse in patients at the first-episode of BD and substance-induced psychosis.