Prevalence, clinical features, and radiological pattern of artery of Percheron infarction: a challenging diagnosis.

PURPOSE: Occlusion of artery of Percheron (AOP), a rare variant of paramedian branches of posterior cerebral artery, results in a characteristic pattern of ischemic lesions in bilateral paramedian thalami with or without midbrain and anterior thalami involvement. AIM: To evaluate the prevalence, the clinical, and the imaging features of AOP infarction in a single comprehensive stroke center experience. METHODS: We retrospectively search in our stroke center database, patients with ischemic lesions in the AOP distribution. We collected clinical features and time between hospital admission and diagnosis. Imaging findings were categorized following a pre-selected classification. RESULTS: Of 2830 ischemic stroke admitted in our center, we identified 15 patients with AOP infarction (0.53%). Clinical manifestations were variable, but oculomotor disturbances, particularly vertical gaze palsy, were the most observed, followed by consciousness impairment, varying from drowsiness to coma. The most frequent imaging pattern was bilateral paramedian thalamic infarction with midbrain infarction, and the V-sign was recognized in 6 cases from this group. In 8 patients a fetal origin of the PCA was observed. The average time from first hospital admission to diagnosis was 28.09 h. CONCLUSIONS: The prevalence of AOP infarction in our center was 0.53%. Diagnosis of AOP infarction can be challenging and should be suspected in case of sudden altered consciousness.

Inferolateral thalamic ischemia secondary to PCA P2 perforator occlusion mimics MCA stroke syndrome.

Paramedian thalamic strokes following occlusion of the posterior medial (paramedian) thalamic perforators have been previously described in great detail. However, the stroke syndrome associated with occlusion of posterior lateral (inferolateral) thalamic perforators is less commonly known. We present an illustrative case of an inferolateral thalamic perforator stroke mimicking a middle cerebral artery (MCA) syndrome and provide a review of the literature. A 62-year-old male presented with dysarthria, contralateral hemisensory loss, and contralateral weakness, concerning for possible MCA stroke. However, close examination revealed the hemiparesis to be ataxic in nature. Imaging revealed a left PCA P2 segment occlusion and lacunar infarction of the ventral lateral (VL) and ventral posterior (VP) thalamus, the main thalamic destination of cerebellar and sensory pathways. The case is unique because the P1 segment and posterior communicating artery (Pcom) remained patent, resulting in selective occlusion of only the posterior lateral (inferolateral) thalamic perforators at the P2 level. Acute loss of the posterior lateral (inferolateral) thalamic perforators at the proximal P2 segment results in a ventral lateral and ventral posterior thalamic stroke characterized by contralateral hemisensory loss, contralateral ataxic hemiparesis, and dysarthria. It is important to recognize the inferolateral thalamic stroke syndrome, as it may be mistaken clinically for an MCA occlusion. The benefit of mechanical thrombectomy for this type of stroke is not well established and should be considered carefully.

Thalamic perforating artery stroke on computed tomography perfusion in a patient with coronavirus disease 2019.

Emerging evidence suggests that patients with coronavirus disease 2019 (COVID-19) are at risk of thromboembolic complications, including ischemic strokes. We present a case illustrating the value of CT perfusion to identify acute small subcortical infarcts in a patient with COVID-19 admitted to an intensive care unit for bilateral pneumonia and pulmonary embolism presenting with sudden right limb weakness.

Clinical syndromes of the thalamic stroke in the classical vascular territories: a prospective hospital-based cohort study.

OBJECTIVE: The aim: We aimed to determine, describe, and analyze the clinical and neuroimaging features of vascular syndromes of acute thalamic stroke in the classical vascular territories in a prospective hospital-based cohort study. PATIENTS AND METHODS: Materials and methods: We have prospectively recruited 319 acute stroke patients, admitted to the Neurological Center at an academic hospital (Oleksandrivska Clinical Hospital) in Kyiv, Ukraine. Complex neurological, clinical, laboratory, ultrasound, and neuroimaging examinations were performed to all study patients within 24 hours since the symptoms onset. RESULTS: Results: MRI/CT-proven thalamic stroke was diagnosed in 34 (10.6%) out of 319 patients, forming a study group. Twenty-two out of 34 patients (average age 61.9 ± 10.2 years) were diagnosed with an acute isolated ischemic thalamic stroke, and 12 patients (average age 59.0 ± 9.6 years) were diagnosed with an acute thalamic hemorrhage. CONCLUSION: Conclusions: Specific neurological features of clinical vascular syndromes of acute thalamic stroke in the classical vascular territories were analyzed, compared, and described.

A case report: Numb Chin Syndrome due to thalamic infarction: a rare case.

BACKGROUND: Numb Chin Syndrome (NCS), which is also characterized as sensory neuropathy of the mental nerve, describes a mostly unilateral numbness of the chin and lower lip. Benign and malignant diseases are known to cause this circumscribed symptom, which can easily be overlooked or misdiagnosed. In this article we present the very rare case of a clinical NCS caused by thalamic lacunar infarction. As a pure sensory stroke it is a rare variant of the Cheiro-Oral Syndrome (COS). CASE PRESENTATION: A 63-year-old male patient received an emergency referral to our department after the patient had noticed a feeling of numbness of the left lower lip and chin on the previous day. The neurological examination revealed an approximately 2 × 3 cm area of hypoesthesia in the area of the chin and left lower lip and the cranial MRI an acute ischemia in the right thalamus. CONCLUSIONS: In this case report we introduce a patient who clinically shows an NCS. Various diseases may be responsible for NCS, including malignancies or even central neurological disorders such as multiple sclerosis. A lacunar thalamic ischemia as a cause of NCS is very rare and to our knowledge described in the literature only in the contex of a COS in three cases. We wish to remind the reader, through this case, of the purely descriptive and syndromal character of the NCS and the importance for detecting underlying diseases. Furthermore we give a brief overview of the NCS and causative disorders.

Artery of Percheron Infarct - a diagnostic and prognostic conundrum!

A 39 year old male was found unconscious at home. On arrival to the hospital the patient was profoundly somnolent but easily rousable, with no focal neurological deficits. Imaging confirmed bilateral thalamic infarcts from the occlusion of Artery of Percheron, a rare anatomic variant which is a single arterial trunk supplying the thalamus and midbrain bilaterally. Anti-platelet therapy was initiated as soon as the diagnosis was established and the patient showed a rapid remarkable recovery over the next 48 hours. He continued to improve subsequently and was at baseline functional status at 6 months. Extensive investigations for etiologies were mostly unrevealing. In such patients presenting with drowsiness/somnolence, a posterior circulation stroke should be considered if no evidence of other more common causes are found. A CT head must be followed by an MRI to confirm the diagnosis and subsequent focus should be on eliciting risk factors and careful evaluation for etiologies.

Midbrain and bilateral paramedian thalamic stroke due to artery of Percheron occlusion.

INTRODUCTION: Bilateral thalamic strokes are rare manifestations of posterior circulation infarcts. Usually the etiology is cardioembolic or small vessel disease combined with individual anatomical predisposition. The symptoms include a variety of neurological deficits depending on thalamic structure involvement, such as paresthesias or numbness, hemiparesis with increased reflexes and Babinski sign, third cranial nerve palsy, speech and cognition disturbance, memory impairment and stupor. Neuroimaging usually reveals ischemic loci in adequate thalamic nuclei. CASE PRESENTATION: We report a case of 61-year-old man, active smoker (25/per day, 50 pack-years) with untreated hypertension who presented at admission consciousness impairment (Glasgow Coma Scale score 9 points), left pupil dilatation without reaction to light, left eye deviation downwards and outwards, vertical gaze paralysis and left-sided hemiplegia. Initial brain computed tomography (CT) was normal. Brain magnetic resonance with diffusion weighted imaging and fluid attenuation inversion recovery sequences (MR DWI/FLAIR) performed on admission showed ischemic changes in bilateral thalami, which were confirmed in routine MRI. Thrombosis of basilar artery and cerebral venous was excluded in CT angiography. Further diagnostic assessment revealed hyperlipidemia, paroxysmal atrial fibrillation and renal cancer with hepatic metastases. CONCLUSION: Bilateral thalamic stroke due to artery of Percheron occlusion is a rare presentation of stroke, which can be overlooked in routine CT scan. If diagnosed, it requires further evaluation for stroke risk factors, especially cardiovascular disorders associated with increased embolic risk.

Lucid dreams, an atypical sleep disturbance in anterior and mediodorsal thalamic strokes.

BACKGROUND: Cognitive, affective, and behavioural disturbances are commonly reported following thalamic strokes. Conversely, sleep disorders are rarely reported in this context. OBSERVATIONS: Herein, we report the cases of two young patients admitted for an ischemic stroke located in the territories of the left pre-mammillary and paramedian arteries. Together with aphasia, memory complaint, impaired attention and executive functions, they reported lucid dreams with catastrophic content or conflicting situations. CONCLUSION: Lucid dreams are an atypical presentation in thalamic strokes. These cases enlarge the clinical spectrum of sleep-wake disturbances potentially observed after an acute cerebrovascular event.

Cognitive and behavioral deficits following bilateral thalamic stroke: a longitudinal study.

We describe behavioral and neuropsychological outcome of a patient (N.S.), who showed a bilateral paramedian thalamic ischemic lesion, with particular reference to the longitudinal evolution of topographical disorientation (TD) and confabulations. We report clinical neuropsychological/behavioral data over a 43-month follow-up. The results show early after the stroke a severe amnesic-confabulatory syndrome with dysexecutive deficits, associated with memory disorders both for visuo-spatial and verbal materials and TD both for known and new places. Behavioral disinhibition and anosognosia for cognitive deficits were also observed. All cognitive impairments have been recovered during the long-term follow-up. Bilateral paramedian thalamic infarcts often lead to severe and long-lasting neurological and cognitive impairments. Only a few cases showed good recovery. Our patient represents an interesting and uncommon case of bilateral paramedian thalamic syndrome with a significant neuropsychological recovery.

An Unusual Case of Thalamic Stroke in a Young Adult With Patent Foramen Ovale and Finasteride Use.

Symptomatic cerebral infarcts with cryptogenic ischemic stroke pose diagnostic challenges due to unknown etiology. Notably, up to half of young individuals with cryptogenic stroke exhibit patent foramen ovale (PFO), while finasteride, which is used for male pattern baldness, elevates testosterone levels, potentially increasing the risk of thrombosis. Here, we present a case of thalamic infarction in a 21-year-old male devoid of cerebrovascular risk factors but with PFO and finasteride use. The patient presented with short-term memory issues, otherwise lacking medical history or substance use. Examination revealed neurological deficits, with imaging indicating a left thalamic infarct. Subsequent investigations identified PFO, prompting referral for closure, yielding symptomatic improvement. Furthermore, discontinuation of finasteride was advised due to its thrombotic association. Finasteride's inhibition of 5-alpha reductase 2 increases testosterone conversion to estrogen, potentially promoting thrombosis. Finasteride use can cause thrombotic events, emphasizing its risk. In conclusion, young embolic stroke patients warrant PFO evaluation alongside hypercoagulable workup, with closure benefiting those under the age of 55. Additionally, discontinuing finasteride may mitigate thrombosis risk.

The Piano Man: A Case Report of Anterior Thalamic Infarct with Dementia and Preserved Music Ability.

OBJECTIVE: The thalamus is the integrative hub of the brain with reciprocal connections throughout the cortex. This case report describes a right-handed 81-year-old male patient who experienced sudden onset cognitive impairment following a focal left anterior thalamic infarct. METHODS: With consent/assent, the patient was seen for a short neuropsychological assessment 6 weeks post stroke. Neuropsychological assessment included review of medical history, collateral intake, the Toronto Cognitive Assessment, Frontal Systems Behavior Scale-Family Rating Form, the Neuropsychiatric Inventory Questionnaire, and piano performance. RESULTS: The assessment revealed impaired performance on measures of orientation, memory, executive function, and language, as well as symptoms including hallucinations, apathy, and hypersomnolence, consistent with thalamic dementia. Remarkably, in this context, the patient maintained an ability to play piano and read music. CONCLUSIONS: The case has implications for understanding the complex integrative functions of the thalamus, including how profound impairment can simultaneously present with cognitive strengths that may not be captured by performance on neuropsychological testing. This case also suggests that magnetic resonance imaging may be indicated in cases presenting with vascular risk factors and sudden onset cognitive impairment, given that computed tomography may not be sensitive to small subcortical infarcts.

Association between functional network connectivity, retina structure and microvasculature, and visual performance in patients after thalamic stroke: An exploratory multi-modality study.

BACKGROUND AND OBJECTIVE: Neuro-ophthalmologic symptoms and retinal changes have been increasingly observed following thalamic stroke, and there is mounting evidence indicating distinct alterations occurring in the vision-related functional network. However, the intrinsic correlations between these changes are not yet fully understood. Our objective was to explore the altered patterns of functional network connectivity and retina parameters, and their correlations with visual performance in patients with thalamic stroke. METHODS: We utilized resting-state functional MRI to obtain multi-modular functional connectivity (FC), and optical coherence tomography-angiography to measure various retina parameters, such as the retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), superficial vascular complex (SVC), and deep vascular complex. Visual acuity (VA) was used as a metric for visual performance. RESULTS: We included 46 patients with first-ever unilateral thalamic stroke (mean age 59.74 ± 10.02 years, 33 males). Significant associations were found between FC of attention-to-default mode and SVC, RNFL, and GCIPL, as well as between FC of attention-to-visual and RNFL (p < .05). Both RNFL and GCIPL exhibited significant associations with FC of visual-to-visual (p < .05). Only GCIPL showed an association with VA (p = .038). Stratified analysis based on a disease duration of 6 months revealed distinct and significant linking patterns in multi-modular FC and specific retina parameters, with varying correlations with VA in each subgroup. CONCLUSION: These findings provide valuable insight into the neural basis of the associations between brain network dysfunction and impaired visual performance in patients with thalamic stroke. Our novel findings have the potential to inform future targeted and individualized therapies. However, further comprehensive studies are necessary to validate our results.

Isolated pseudo­abducens palsy and contralateral occipital headache with thalamic stroke: A case report and mini­review of the literature.

The abducens nerve (sixth cranial nerve) is essential for lateral eye movement, and its malfunction can cause a variety of issues with vision. Pseudo-abducens palsy is a rare neurological condition that causes a limitation in eye abduction, while the abducens nerve is still functioning. Thalamic pain syndrome, a severe complication of cerebrovascular events, presents as intense neuropathic pain provoked by temperature fluctuations. Although thalamic strokes are infrequently associated with ocular abnormalities, some studies suggest an association between isolated pseudo-abducens palsy and thalamic infarctions. The present study describes the case of a 38-year-old male patient with 1-day progressive diplopia and occipital headache who had abducens palsy on the left side as a result of a right thalamic infarction. The patient had a 10-year history of smoking and a 1-year history of hypertension, which was poorly controlled. The diagnosis was supported by a neurological examination, imaging and stroke etiology investigations. The patient recovered well within 5 days, highlighting the good prognosis of an acute thalamic presentation. In addition, a mini-review of the literature was performed and two similar reports were identified upon searching the literature using the Embase, Google Scholar, Lilacs, Medline, SciELO and ScienceDirect databases. On the whole, the present study demonstrates that understanding the complex neuronal connections inside the thalamus is critical for a proper diagnosis and appropriate intervention strategies in patients with thalamic stroke with oculomotor impairments. Further research is required to elucidate the underlying causes and develop treatment techniques for thalamic infarction consequences.

ANTERIOR THALAMIC ISCHAEMIC STROKE SECONDARY TO CARDIOPULMONARY ARREST.

Introduction: Ischaemic anterior thalamic lesions are rare and can present with disturbances of behaviour and memory. We describe a patient with post-cardiac arrest thalamic stroke. Case description: A 63-year-old man presented with cardiac arrest, was resuscitated after receiving life support, and showed no lesions on computed tomography. Three days later, he presented with short-term memory disturbance and disorientation, with a de novo anterior thalamic lesion. Conclusion: The anterior thalamic nucleus, supplied by the posterior communicating artery, is part of the Papez circuit and has a role in modulating behaviour and memory. An anterior thalamic syndrome presents with no sensory-motor deficits. LEARNING POINTS: Anterior thalamic stroke is a rare condition and can present with disturbances of short-term memory and behaviour; it usually does not include any motor or sensory deficits.Thalamic stroke can occur due to global hypoxia, such as during cardiopulmonary arrest.

Clinical review and analysis of artery of Percheron infarction.

Artery of Percheron infarction is a rare one of the neurovascular structure variants of acute ischemic stroke characterized by bilateral paramedian thalamic infarcts (BTPI), with or without mesencephalic infarction. Due to the low occurrence rate and various clinical manifestations, the early diagnosis of this disease is often missed. In addition, it is also difficult to diagnose this disease in an early implementation phase because cranial imaging and intracranial vascular imaging may show negative results. So far, its clinical cases have been rarely reported. We systematically reviewed the clinical manifestations, imaging characteristics, anatomical basis, and differentiation diagnosis of the artery of Percheron infarction and reported on three patients and their clinical and radiological medical imaging characteristic findings. We found that most of the infarct lesions in patients with an AOP infraction could not be displayed within a few hours or could not be fully displayed, even the embolism events, most of which showed typical imaging lesions at late review. The decrease of transient consciousness was obvious over the course of the three patients, and the decrease of active communication was also a major feature. Among the three cases, one patient had unilateral upper eyelid ptosis and miosis; the initial symptom of another patient was dizziness; and the other person had decreased computing power after infarction. These clinical symptoms are easily ignored in the diagnosis and treatment of patients with AOP infarction. Therefore, reporting the three clinical cases mentioned above will provide assistance for subsequent research by increasing clinical data.

Alterations of optic tract and retinal structure in patients after thalamic stroke.

Objectives: To investigate the association between degeneration of retinal structure and shrinkage of the optic tract in patients after thalamic stroke. Materials and methods: Patients with unilateral thalamic stroke were included. Structural magnetic resonance imaging (MRI) and optical coherence tomography (OCT) were performed to obtain parameters of optic tract shrinkage (lateral index) and retina structural thickness (retinal nerve fiber layer, RNFL; peripapillary retinal nerve fiber layer, pRNFL; ganglion cell-inner plexiform layer, GCIP), respectively. Visual acuity (VA) examination under illumination was conducted using Snellen charts and then converted to the logarithm of the minimum angle of resolution (LogMAR). We investigated the association between LI and OCT parameters and their relationships with VA. Results: A total of 33 patients and 23 age-sex matched stroke-free healthy controls were enrolled. Patients with thalamic stroke showed altered LI compared with control participants (P = 0.011) and a significantly increased value of LI in the subgroup of disease duration more than 6 months (P = 0.004). In these patients, LI were significantly associated with pRNFL thickness (ß = 0.349, 95% confidence interval [CI]: 0.134-0.564, P = 0.002) after adjusting for confounders (age, sex, hypertension, diabetes, dyslipidemia, and lesion volume). LI and pRNFL were both significantly associated with VA in all patients (LI: ß = -0.275, 95% CI: -0.539 to -0.011, P = 0.041; pRNFL: ß = -0.023, 95% CI: -0.046 to -0.001, P = 0.040) and in subgroup of disease duration more than 6 months (LI: ß = -0.290, 95% CI: -0.469 to -0.111, P = 0.002; pRNFL: ß = -0.041, 95% CI: -0.065 to -0.017, P = 0.003). Conclusion: Shrinkage of the optic tract can be detected in patients with thalamic stroke, especially after 6 months of stroke onset. In these patients, the extent of optic tract atrophy is associated with pRNFL thickness, and they are both related to visual acuity changes.

Case report: Improved behavioral and psychiatric symptoms with repetitive transcranial magnetic stimulation at the bilateral DLPFC combined with cognitive and behavioral therapy in a patient with unilateral thalamic hemorrhage.

Behavioral and psychological symptoms are not uncommon after thalamic stroke, and are often intractable despite medication and behavioral interventions. Repetitive transcranial magnetic stimulation (rTMS) is as an adjunctive therapeutic tool for neuropsychiatric diseases, and bilateral rTMS has been recently introduced to maximize the therapeutic effect. Herein, we report the case details of a patient with unilateral left thalamic hemorrhage without cortical lesions who had treatment-resistant neuropsychiatric symptoms. We hypothesized that bilateral rTMS targeting the bilateral dorsolateral prefrontal cortices (DLPFCs) would positively affect thalamocortical neural connections and result in neuropsychiatric symptom improvement. The patient received a total of 10 sessions of bilateral rTMS over 2 weeks, applied at the DLPFCs, with high frequency in the left hemisphere and low frequency in the right hemisphere. After each rTMS treatment, computer-based cognitive-behavioral therapy was administered for 30 min. Behavioral and psychological symptoms, including hallucinations, aggressiveness, aberrant motor activity, disinhibition, and abrupt emotional changes, were significantly improved as assessed by the Neuropsychiatric Inventory Questionnaire. These effects persisted for up to 1 month. This case demonstrates the clinical potential of bilateral rTMS treatment in patients with intractable neurocognitive impairment after thalamic stroke.

Endovascular intervention for bilateral paramedian thalamic stroke due to occlusion of the unilateral P1 segment of the posterior cerebral artery: illustrative cases.

BACKGROUND: Occlusion of the unilateral P1 segment can result in bilateral paramedian thalamic infarction in patients with anatomical variants of the bilateral paramedian thalamic artery arising from a single P1 segment. Despite the life-threatening presentation of bilateral paramedian thalamic stroke, timely diagnosis is often challenging. OBSERVATIONS: The authors herein describe 3 patients treated with endovascular intervention for occlusion of the unilateral P1 segment wherein the bilateral paramedian thalamic arteries arose. All patients were admitted to the authors' emergency department with sudden-onset coma and respiratory distress; however, initial computed tomography was unremarkable. Despite suspicion of basilar artery occlusion, vertebral and carotid angiography revealed occlusion of the unilateral P1 segment. All patients were successfully treated with endovascular intervention. Overall, 2 patients had favorable outcomes (modified Rankin scale [mRS] scores of 0 and 1), whereas in 1 patient, the mRS score reached a baseline score of 3. LESSONS: In patients with the variant of the bilateral paramedian thalamic artery arising from a single P1 segment, occlusion of the unilateral P1 segment can be life threatening; nevertheless, timely endovascular treatment is effective. Carotid and vertebral angiography, rather than magnetic resonance or computed tomography angiography, is useful for immediate and reliable diagnosis of the relatively small vascular lesions.

Rare coexistence of multiple manifestations secondary to thalamic hemorrhage: A case report.

BACKGROUND: A growing body of literature indicates that the occurrence of thalamic lesions could lead to various dysfunctions, such as somatosensory disturbances, hemiparesis, language deficits, and movement disorders. However, clinical cases describing the coexistence of these types of manifestations have not been reported. Herein, we report a patient who exhibited these rare complications secondary to thalamic hemorrhage. CASE SUMMARY: A 53-year-old right-handed man experienced sudden left hemiparesis, numbness of the left side of body, and language alterations due to an acute hemorrhage located in the right basal ganglia and thalamus 18 mo ago. Approximately 17 mo after the onset of stroke, he exhibited rare complications including dysphasia, kinetic tremor confined to the left calf, and mirror movement of the left arm which are unique and interesting, and a follow-up computed tomography scan revealed an old hemorrhagic lesion in the right thalamus and posterior limb of the internal capsule. CONCLUSION: Hypophonia may be a recognizable clinical sign of thalamus lesions; thalamus injury could cause tremor confined to the lower extremity and mimicking extremity movements.