Analysis of neuropsychological and neuroradiological features for diagnosis of Alzheimer's disease and mild cognitive impairment.

BACKGROUND: Age-related neurodegenerative diseases are constantly increasing with prediction that in 2050 over 60 % of population will suffer from some level of cognitive impairment. A cure for the Alzheimer's disease (AD) does not exist, so early diagnosis is of a great importance. Machine learning techniques can help in early diagnosis with deep medical data processing, disease understanding, intervention analysis and knowledge discovery for achieving better medical decision making. METHODS: In this paper, we analyze the dataset consisting of 90 individuals and 482 input features. We investigate the achieved AD prediction performances using seven classifiers and five feature selection algorithms. We pay special focus on analyzing performance by utilizing only a subset of best ranked attributes to establish the minimum amount of input features that ensure acceptable performance. We also investigate the significance of neuropsychological (NP) and neuroradiological (NR) attributes for the AD diagnosis. RESULTS: The accuracy for the whole set of attributes ranged between 66.22 % and 81.00 %, and the weighted average AUROC was between 76.3 % and 95.0 %. The best results were achieved by the naive Bayes classifier and the Relief feature selection algorithm. Additionally, Support Vector Machines classifier shows the most stable results since it depends the least on the feature selection algorithm which is used. As the main result of this paper, we compare the performance of models trained with automatically selected features to models trained with hand-selected features performed by medical experts (NP and NR features). CONCLUSIONS: The results reveal that unlike the NR attributes, the NP attributes achieve a good performance that is comparable to the full set of attributes, which suggests that they possess a high predictive power for AD diagnosis.

Absence of Oligoclonal Bands in Multiple Sclerosis: A Call for Differential Diagnosis.

BACKGROUND: Immunoglobulin gamma (IgG) oligoclonal bands (OCB) in the cerebrospinal fluid (CSF) are absent in a small group of multiple sclerosis (MS) patients. According to previous research, OCB-negative MS patients differ genetically but not clinically from OCB-positive MS patients. However, whether OCB-negative MS is a unique immunological and clinical entity remains unclear. The absence of OCB poses a significant challenge in diagnosing MS. (1) Objective: The objective of this study was twofold: (1) to determine the prevalence of OCB-negative MS patients in the Uppsala region, and (2) to assess the frequency of misdiagnosis in this patient group. (2) Methods: We conducted a retrospective study using data from the Swedish MS registry (SMSreg) covering 83% of prevalent MS cases up to 20 June 2020 to identify all MS patients in the Uppsala region. Subsequently, we collected relevant information from the medical records of all OCB-negative MS cases, including age of onset, gender, presenting symptoms, MRI features, phenotype, Expanded Disability Status Scale (EDSS) scores, and disease-modifying therapies (DMTs). (3) Results: Out of 759 MS patients identified, 69 had an OCB-negative MS diagnosis. Upon re-evaluation, 46 patients had a typical history and MRI findings of MS, while 23 had unusual clinical and/or radiologic features. An alternative diagnosis was established for the latter group, confirming the incorrectness of the initial MS diagnosis. The average EDSS score was 2.0 points higher in the MS group than in the non-MS group (p = 0.001). The overall misdiagnosis rate in the cohort was 33%, with 22% of misdiagnosed patients having received DMTs. (4) Conclusions: Our results confirm that the absence of OCB in the CSF should raise suspicion of possible misdiagnosis in MS patients and prompt a diagnostic reassessment.

Outcome after microvascular decompression for trigeminal neuralgia in a single center-relation to sex and severity of neurovascular conflict.

BACKGROUND: Trigeminal neuralgia (TN), a severe type of facial pain, is mainly caused by a neurovascular conflict (NVC). The severity of the NVC seems associated with the outcome following microvascular decompression (MVD) surgery. This study aimed to investigate the outcome after MVD and whether it is affected by NVC severity and sex. METHODS: TN patients (n = 109) were followed for 5 to 10 years after MVD. Barrow Neurology Index (BNI), Patients Global Impression of Change (PGIC), complications, and time to relapse were evaluated. The NVC severity was retrospectively reviewed from presurgical MRI. Demographic and clinical factors and NVC severity were analyzed for potential association with outcome after MVD. RESULTS: The success rate (BNI ≤ 2) was 80% after 5 to 10 years follow-up for TN patients with severe NVC (grade 2-3) and 56% for TN patients with mild NVC (grade 0-1, P = 0.003). No sex difference was observed in outcome for patients with both mild (P = 0.924) and severe NVC (P = 0.883) respectively. Three patients (2.8%) during the hospital stay, and two patients (1.8%) at 6 weeks, experienced a complication requiring invasive treatment. At long-term 52/109 patients (47.7%) reported some type of persistent adverse event, of which the majority were mild and required no treatment. CONCLUSIONS: MVD offers an 80% probability of long-term pain relief in TN patients with severe NVC, with low frequency of serious complications. NVC severity significantly affects outcome after MVD, while no sex differences in outcome were found. In consistency with previous work, the results stress the importance of adequate neuroradiological assessment of the NVC for preoperative patient selection.

High-Field Magnetic Resonance Imaging of the Temporomandibular Joint Low Agreement with Clinical Diagnosis in Asymptomatic Females.

(1) Background: The aim of this study was to investigate the agreement between a clinical diagnosis based on research diagnostic criteria/temporomandibular disorders (RDC/TMD) and high-field magnetic resonance imaging (MRI) findings of temporomandibular joints (TMJs) in asymptomatic females. (2) Methods: A prospective study on 100 females (200 TMJs) was performed, using clinical examinations (RDC/TMD) and same-day MRIs of TMJs on a 3T MR unit. The inclusion criteria were as follows: females, age > 18, the presence of upper and lower incisors, and an understanding of the Serbian language. Descriptive statistics (means and standard deviations) and ANOVA with a post hoc Tukey test for differences among the patient subgroups was performed. The agreement between the clinical and MRI findings was determined using Cohen's kappa coefficient (k < 0.21 slight, 0.21-0.4 fair, 0.41-0.6 moderate, 0.61-0.8 substantial, and 0.81-1 almost perfect). The statistical significance was set at p ≤ 0.05. (3) Results: Normal findings were observed in 86.7%, disc dislocation (DD) was observed in 9.2%, and arthralgia/osteoarthritis/osteoarthrosis was observed in 2.6% of TMJs using RDC/TMD. On the MRI, normal findings were observed in 50.5%, disc dislocation was observed in 16.3%, and arthralgia/osteoarthritis/osteoarthrosis was observed in 23.5% of TMJs. The anterior DD with reduction showed fair agreement of the clinical and MRI findings (k = 0.240, p < 0.001) compared with the DD without reduction (k = 0.355, p < 0.001). Both showed high specificity (94.9% and 99.4%) but low sensitivity (24.2% and 25.0%). The sensitivity in osteoarthritic changes was low (4.8%), but the specificity remained high (96.2%). (4) Conclusions: The sensitivity of the clinical examination remains low compared with 3T MRI, especially in osteoarthritic changes and anterior DD with reduction. However, the number of false positive diagnoses using RDC/TMD is low in asymptomatic patients. RDC/TMD remains a sensible method for establishing a clinical diagnosis and avoiding the overtreatment of asymptomatic patients.

Endovascular treatment of type 1 and type 4 non-saccular aneurysms of cerebral arteries - a single-Centre experience.

AIM OF THE STUDY: The aim of this study was to evaluate our results regarding treatment options, complications, and outcomes in patients with non-saccular aneurysms of cerebral arteries belonging to type 1 and type 4 according to Mizutani's classification. METHODS: A total of 26 aneurysms in 26 patients were treated between 2014 and 2019. There were 13 males (mean age 42.77 ± 11.73 years) and 13 females (mean age 50.84 ± 9.37 years). In 23 cases the onset was haemorrhagic and in three cases non-haemorrhagic. A combination of conventional stents and coils was used in 10 cases, conventional stents and flow diverters in three cases, flow diverters and coils in five cases, and flow diverters only were used in eight cases. Radiological results of treatment were assessed after eight months and clinical after one year. RESULTS: In 24 patients, aneurysms were occluded at the end of the follow-up period. An iatrogenic dissection and two haemorrhagic complications were registered. In three cases, parent arteries were occluded due to re-growth of the aneurysm, which caused middle cerebral artery infarction in one case. A favourable clinical outcome was registered in 19, patients, and non-favourable in five. Two patients died in the early postoperative period due to extensive damage to the brain parenchyma caused by initial bleeding. CONCLUSION: Our results indicate that treatment of type 1 and type 4 non-saccular aneurysms with various combination of stents and flow diverters, with or without coils, is promising, although very challenging and technically demanding.

Time course of neurological deficits after surgery for primary brain tumours.

BACKGROUND: The postoperative course after surgery for primary brain tumours can be difficult to predict. We examined the time course of postoperative neurological deficits and analysed possible predisposing factors. METHOD: Hundred adults with a radiological suspicion of low- or high-grade glioma were prospectively included and the postoperative course analysed. Possible predictors of postoperative neurological deterioration were evaluated. RESULTS: New postoperative neurologic deficits occurred in 37% of the patients, and in 4%, there were worsening of a preoperative deficit. In 78%, the deficits occurred directly after surgery. The probable cause of deterioration was EEG-verified seizures in 7, ischemic lesion in 5 and both in 1, resection of eloquent tissue in 6, resection close to eloquent tissue including SMA in 11 and postoperative haematoma in 1 patient. Seizures were the main cause of delayed neurological deterioration. Two-thirds of patients with postoperative deterioration showed complete regression of the deficits, and in 6% of all patients, there was a slight disturbance of the function after 3 months. Remaining deficits were found in 6% and only in patients with preoperative neurological deficits and high-grade tumours with mainly eloquent locations. Eloquent tumour location was a predictor of postoperative neurological deterioration and preoperative neurological deficits of remaining deficits. CONCLUSIONS: Postoperative neurological deficits occurred in 41% and remained in 6% of patients. Remaining deficits were found in patients with preoperative neurological deficits and high-grade tumours with mainly eloquent locations. Eloquent tumour location was a predictor of neurological deterioration and preoperative neurological deficits of remaining deficits.

Aniridia with PAX6 mutations and narcolepsy.

PAX6 gene mutations cause a variety of eye and central nervous system (CNS) abnormalities. Aniridia is often accompanied by CNS abnormalities such as pineal gland atrophy or hypoplasia, leading to disturbed circadian rhythm and sleep disorders. Less is known on the coincidence of narcolepsy in this patient group. We aimed to find out whether the circadian rhythm or sleep-wake structure was affected in patients with aniridia. Four members of a family segregating with congenital aniridia in two generations were included in the study. The patients were subjected to genetic testing for a PAX6 mutation, multiple sleep latency test, whole-brain magnetic resonance imaging (MRI), hypocretin-1 in cerebrospinal fluid, and Human Leukocyte Antigen DQ beta1*06:02. All four members were heterozygous for the pathogenic c.959-1G>A mutation in the PAX6 gene. Sleep disturbance was observed in all family members. The index patient was diagnosed with narcolepsy. MRI showed a hypoplastic pineal gland in all members. We describe the first case of a patient with PAX6 haploinsufficiency, aniridia and pineal gland hypoplasia diagnosed with narcolepsy type-1, suggesting a complex sleep disorder pathogenesis.

Continuous EEG monitoring after brain tumor surgery.

BACKGROUND: Prolonged seizures generate cerebral hypoxia and increased intracranial pressure, resulting in an increased risk of neurological deterioration, increased long-term morbidity, and shorter survival. Seizures should be recognized early and treated promptly. The aim of the study was to investigate the occurrence of postoperative seizures in patients undergoing craniotomy for primary brain tumors and to determine if non-convulsive seizures could explain some of the postoperative neurological deterioration that may occur after surgery. METHODS: A single-center prospective study of 100 patients with suspected glioma. Participants were studied with EEG and video recording for at least 24 h after surgery. RESULTS: Seven patients (7%) displayed seizure activity on EEG recording within 24 h after surgery and another two patients (2%) developed late seizures. One of the patients with early seizures also developed late seizures. In five patients (5%), there were non-convulsive seizures. Four of these patients had a combination of clinically overt and non-convulsive seizures and in one patient, all seizures were non-convulsive. The non-convulsive seizures accounted for the majority of total seizure time in those patients. Non-convulsive seizures could not explain six cases of unexpected postoperative neurological deterioration. Postoperative ischemic lesions were more common in patients with early postoperative seizures. CONCLUSIONS: Early seizures, including non-convulsive, occurred in 7% of our patients. Within this group, non-convulsive seizure activity had longer durations than clinically overt seizures, but only 1% of patients had exclusively non-convulsive seizures. Seizures were not associated with unexpected neurological deterioration.

HIV-associated neurodegeneration and neuroimmunity: multivoxel MR spectroscopy study in drug-naïve and treated patients.

OBJECTIVES: The aim of this study was to test neurobiochemical changes in normal appearing brain tissue in HIV+ patients receiving and not receiving combined antiretroviral therapy (cART) and healthy controls, using multivoxel MR spectroscopy (mvMRS). METHODS: We performed long- and short-echo 3D mvMRS in 110 neuroasymptomatic subjects (32 HIV+ subjects on cART, 28 HIV+ therapy-naïve subjects and 50 healthy controls) on a 3T MR scanner, targeting frontal and parietal supracallosal subcortical and deep white matter and cingulate gyrus (NAA/Cr, Cho/Cr and mI/Cr ratios were analysed). The statistical value was set at p < 0.05. RESULTS: Considering differences between HIV-infected and healthy subjects, there was a significant decrease in the NAA/Cr ratio in HIV+ subjects in all observed locations, an increase in mI/Cr levels in the anterior cingulate gyrus (ACG), and no significant differences in Cho/Cr ratios, except in ACG, where the increase showed trending towards significance in HIV+ patients. There were no significant differences between HIV+ patients on and without cART in all three ratios. CONCLUSION: Neuronal loss and dysfunction affects the whole brain volume in HIV-infected patients. Unfortunately, cART appears to be ineffective in halting accelerated neurodegenerative process induced by HIV but is partially effective in preventing glial proliferation. KEY POINTS: • This is the first multivoxel human brain 3T MRS study in HIV. • All observed areas of the brain are affected by neurodegenerative process. • Cingulate gyrus and subcortical white matter are most vulnerable to HIV-induced neurodegeneration. • cART is effective in control of inflammation but ineffective in preventing neurodegeneration.

Atypical, polyarticular lipoma arborescens in a child.

Introduction: Lipoma arborescens is a rare, tumor-like lesion commonly involving synovial joints and less commonly bursae and synovial tendon sheaths. Case Outline: We report a case of a 12-year-old boy with symmetric involvement of the bicipitoradial bursae, synovial sheaths of extensor compartments of both hands and medial ankles. The diagnosis of polyarticular lipoma arborescens was proposed on magnetic resonance (MR) imaging and this diagnosis was histologically proven after biopsy of the bursae and later by open surgery of the synovial sheath of the right ankle tendons. Literature search was performed and twelve cases with polyarticular involvement were analyzed. Lipoma arborescens commonly involves suprapatellar recess of the knee and very rarely other joints or bursae. Histological analysis revealed an accompanying non-necrotizing granulomatous synovial inflammation. Conclusion: Polyarticular lipoma arborescens is a rare entity and symmetrical involvement of the joints other than the knees is exceedingly rare. MR imaging plays a significant role in the diagnostic protocol, and the characteristic fatty signal on MR imaging is highly suggestive of lipoma arborescens.

Segmental cavernous carotid ectasia in a patient with cluster-like headache.

INTRODUCTION: Cluster headache (CH) is a primary headache with severe, unilateral periorbital or temporal pain lasting 15-180 min, accompanied with various cranial autonomic features. A diagnosis of cluster-like headache can be made whenever underlying cause of CLH is present. METHODS AND RESULTS: We report a case where an ectatic cavernous segment of the internal carotid artery triggered CHL, most probably due to compression of the ophthalmic nerve within cavernous sinus. The pathological substrate of a vessel ectasia is degeneration of the tunica intima as a consequence of atherosclerosis and hypertension. On the other hand, cavernous sinus is unique space where parasympathetic, sympathetic and nociceptive fibers are in intimate relationship which is of great importance for understanding of CH pathophysiology. CONCLUSION: Magnetic resonance imaging and MR angiography are mandatory imaging tools used for precise localization of pathological changes in the cavernous sinus, especially in the group of secondary headaches attributed to vascular disorders.

Magnetic resonance imaging comparison of lateral collateral ligament and patellar tendon length.

INTRODUCTION: The problem of using patellar tendon auto or allografts for lateral collateral ligament reconstruction results in the occurrence of ligaments mismatch. The length of patellar tendon does not match the lateral collateral ligament. MATERIAL AND METHODS: Out of 151 patients, who formed the study, 102 were men with the mean age of 30 years (18-54) and 49 women, with the mean age of 34 (18-55), and they all underwent magnetic resonance imaging of the knee. Both patellar tendon and lateral collateral ligament were measured using a three-dimensional isovoxel true-fast-imaging with steady-state precession sequence with water excitation and secondary multiplanar reformations. In order to visualize the lateral collateral ligament insertions precisely, sagittal images were reformatted according to the anatomical, oblique ligament position, in anteriorly tilted, paracoronal plane. The length of the patellar tendon was measured from the patellar apex to the tibial tuberosity insertion site. RESULTS: The mean patellar tendon length was 52.88 +/- 7.56 mm (37-75) with a significant difference between men and women. The mean lateral collateral ligament length was 61.21 +/- 5.77 mm (46-80) with a significant difference between genders. The average differences between lateral collateral ligament and patellar tendon length was 8.38 +/- 7.23 mm (-9 to 26) without a significant difference between the genders. In 18 (11.92%) patients, the patellar tendon was longer than the lateral collateral ligament; in 7 patients (4.63%) they were equal; and in 126 patients (83.44%) the patellar tendon was shorter than the lateral collateral ligament. CONCLUSION: The length of patellar tendon does not match the length of lateral collateral ligament. If patellar tendon auto or allograft is used for lateral collateral ligament reconstruction, the lengths of both ligaments must be determined preoperatively in order to avoid intraoperative complications.

Perineural tumor spread - Interconnection between spinal and cranial nerves.

The secondary neoplastic involvement of the cervical plexus in patients with head and neck malignancies is extremely rare. MR examination of the neck revealed the diffuse neoplastic infiltration of the right C2 root, in a 57-year-old patient with several months long pain in the right ear region and a history of the tongue squamous cell carcinoma. Associated perineural tumor spread and consequent distal involvement of great auricular nerve and vagus nerve were evident. Best of our knowledge, this is the first reported involvement of the cervical plexus in patients with head and neck cancers, associated with the clearly documented interconnection between the cervical plexus and cranial nerves via great auricular nerve.

White matter lesions and depression in patients with Parkinson's disease.

Depression is frequently associated with Parkinson disease (PD) but neural basis is still unclear. In previous studies white matter changes present as signal hyperintesities on T2-wighted MRI studies (WMHs) commonly observed in older adults have been associated with depressive symptomatology. In this study we investigated whether WMHs were associated with depression in PD patients with disease onset above the age of 60. Thirty-four patients, with (PD-D) and 25 without depression (PD-nD), and 30 healthy age- and sex-matched controls were analyzed using the Scheltens visual rating scale. Cerebrovascular risk factors were similar across groups. Comparing controls and PD patients as a group there were no differences in WMHs in any examined regions. However, PD-D group had more common frontal WMHs although WMHs score didn't rich statistical significance. The same came true for total deep white matter changes comparing those two groups. In addition PD-D group had a significantly higher score for periventricular regions WMHs comparing with both PD-nD group and controls.PD-D group had significantly higher WMHs scores BG regions when compared to controls. The only significance in multivariate analyses was shown for periventricular WMHs total score explaining the 39% of the variance in the depressive score. Our findings suggest that WMH in the deep white matter may contribute to depression in PD.

Multivoxel MRS: right frontal parafalcine cortex - area of neurobiochemical gender differentiation?

OBJECTIVE: To determine the presence of gender neurometabolic differences in healthy men and women by multivoxel magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: We performed multivoxel magnetic resonance imaging and spectroscopy in 50 healthy volunteers (27 women and 23 men) using 1.5T scanner. Spectra from 12 different voxels were obtained, covering frontal, paracentral, and parietal white and gray matter. Three dominant signals were analyzed: NAA, tCr and Cho, and expressed as ratios of Cho/tCr, NAA/tCr, NAA/Cho. RESULTS: There was statistically significant gender difference between Cho/Cr and NAA/Cr metabolites ratio in only one location - the right frontal parafalcine cortex. There was no statistically significant difference in NAA/Cho ratio between men and women. CONCLUSION: Our study suggests that right frontal parafalcine cortex is a sexually dysmorphic area and supports the value of multivoxel MRS as a method able to define spatial biochemical heterogeneity of the cerebral tissue.

MR and MRS characteristics of intraventricular meningioma.

Meningiomas are frequent intracranial, non-glial tumors of adults. We present the unusual left lateral ventricular localization of meningioma in a 51-year-old man. The magnetic resonance (MR) images showed well demarcated, large mass of the atrium of the left lateral ventricle with transependymal extension into the left temporal lobe. MR spectroscopy revealed the presence of "choline only" spectrum, typical for extra axial neoplasms. The mass was completely resected. The diagnosis of transitional type intraventricular meningioma, with psammoma bodies, histologic grade I was made. Progesterone and estrogen receptors were negative.

MR imaging - an unreliable and potentially misleading diagnostic modality in patients with intracerebral calcium depositions. Case report.

BACKGROUND: Since magnetic resonance imaging (MRI) is a method of choice for establishing the correct diagnosis in a great majority of neurologic disorders, especially in detection the causes of seizures and both acute and slowly progressive neurologic disturbances, computerized tomography is becoming more frequently excluded from obligate spectrum of diagnostic protocol. METHODS: MRI was performed on 1.5 T MR scanner in two patients, in one suffering from pseudohypoparathyroidism, and in another with Fahr disease, while CT was initially excluded from the diagnostic protocol. In third patient, 11-year-old boy with hypercalcemia, both CT and MRI were indicated because of seizure attack. RESULTS: Completely normal appearing brain parenchyma was seen on T2W images in a patient with clinical diagnosis of pseudohypoparathyroidism while extensive intracerebral calcifications were noted after additionally performed computerized tomography of the brain. In another patient with Fahr disease and neurologic symptoms, extensive calcifications were evident on CT, while MR examination had revealed bilateral symmetric lesions of prolonged T2W signal in the basal ganglia, supratentorial white matter and cerebellum, most compatible toxic/metabolic demyelination. In the third patient, a boy with hypercalcemia, marked left parietal cortical calcification was noted on CT, while MRI, including T2 gradient-echo sequence was inconclusive. CONCLUSIONS: MRI, without CT, can be not only confusing, but even misleading diagnostic modality for detection of not only subtle, but also extensive cerebral calcifications. The benefit of gradient-echo T2 sequence, that is usually included in MR protocol when intracranial calcifications are suspected, is also rather limited.

Brain white matter 1 H MRS in Leber optic neuropathy mutation carriers.

OBJECTIVE: This study was conducted in order to test the hypothesis that proton MR spectroscopic (1H MRS) profile of Leber's hereditary optic neuropathy (LHON) mutation carriers group (including both symptomatic and asymptomatic) differs from group of healthy individuals and to determine metabolite or ratio that contributes most to differentiation. PATIENTS AND METHODS: We performed single voxel 1H MRS in normal appearing white matter of eighteen LHON mtDNA mutation carriers bearing one of three LHON mtDNA point mutations and in fifty control subjects. RESULTS: ANOVA showed significant difference for absolute concentration of creatine (Cr) (p < 0.01) and N-acetylaspartate to creatine ratio (NAA/Cr) (p < 0.01). Discriminant analysis revealed that decreased absolute Cr followed by decreased absolute NAA concentration have the most significant contribution in discriminating LHON mutation carriers from healthy controls. CONCLUSION: Abnormal metabolic profile in normal appearing white matter on MR imaging seems to be significantly present in LHON mutation carriers.