Slow progressive bilateral posterior artery infarction presenting as agitated delirium, complicated with Anton's syndrome

Diagnostic Approach to the Patient with Altered Mental Status

Acute encephalopathy is a common presenting symptom in the emergency room and complicates many hospital and intensive care unit admissions. The evaluation of patients with encephalopathy poses several challenges: limited history and examination due to the patient's mental status, broad differential diagnosis of systemic and neurologic etiologies, low yield of neurodiagnostic testing due to the high base rate of systemic causes, and the importance of identifying less common neurologic causes of encephalopathy that can be life-threatening if not identified and treated. This article discusses the differential diagnosis of acute encephalopathy, presents an approach to the history and examination in a patient with encephalopathy, reviews the literature on the yield of neurodiagnostic testing in this population, and provides a diagnostic framework for the evaluation of patients with altered mental status.

Post-stroke aggressive behavior in patients wıth first-ever ischemic stroke: underlying clinical and imaging factors

BACKGROUND

Aggression is defined as a complex behavior consisting of a combination of sensory, emotional, cognitive and motor elements. We aimed to examine the relationships between post-stroke aggressive behavior (PSAB) and neuropsychological and neuroimaging findings.

METHODS

380 patients in the stroke unit were classified as aggressive or non-aggressive based on symptoms elicited by the Neuropsychiatric Inventory (NPI) and aggression screening questionnaire.

RESULTS

Aggressive behavior was detected in 42 (11.1%) of 380 patients who had a first ischemic stroke. Patients with PSAB were older than those without (338 patients) (66.98 + 13.68 vs. 62.61 + 13.06, P = 0.043). Hamilton depression and anxiety scales showed significantly higher rates of depression and anxiety in the PSAB group compared to the non-PSAB group (47.6% vs. 16.3% and 57.1% vs. 15.4%, respectively; P = 0.001). Lesion mapping analysis showed that lesions in patients with PSAB mostly included the lower parietal lobe and lateral frontal gyrus. Multiple regression analysis showed that gender (OR, 2.81; CI%, 1.24-6.39), lateral prefrontal infarction (OR, 6.43; CI%, 1.51-27.44), parietal infarction (OR, 2.98; CI%, 1.15-7.76), occipital infarction (OR, 2.84; CI%, 1.00-8.06), multiple infarcts (OR, 5.62; CI%, 2.27-13.93), anxiety (OR, 2.06; CI%, 0.89-4.81) and verbal memory deficit (OR, 4.21; CI%, 1.37-12.93) were significant independent predictors of PSAB.

CONCLUSION

The presence of PSAB may be related to neuropsychiatric symptoms such as high anxiety and verbal memory impairment, and neuroanatomical location of the lesions.

Insights into Anton Syndrome: When the brain denies blindness

INTRODUCTION

Anosognosia, a neurological condition, involves a lack of awareness of one's neurological or psychiatric deficits. Anton Syndrome (AS), an unusual form of anosognosia, manifests as bilateral vision loss coupled with denial of blindness. This systematic review delves into 64 studies encompassing 72 AS cases to explore demographics, clinical presentations, treatments, and outcomes.

MATERIALS AND METHODS

The study rigorously followed PRISMA guidelines, screening PubMed, Google Scholar, and Scopus databases without timeframe limitations. Only English human studies providing full text were included. Data underwent thorough assessment, examining patient demographics, etiological variables, and treatment modalities.

RESULTS

Sixty-four studies met the stringent inclusion criteria. Examining 72 AS cases showed a median age of 55 (6 to 96 years) with no gender preference. Hypertension (34.7 %) and visual anosognosia (90.3 %) were prevalent. Stroke (40.3 %) topped causes. Management included supportive (30.6 %) and causal approaches (30.6 %). Improvement was seen in 45.8 %, unchanged in 22.2 %, and deterioration in 11.1 %. Anticoagulation correlated with higher mortality (p < 0.05).

DISCUSSION

AS, an unusual manifestation of blindness, stems mainly from occipital lobe damage, often due to cerebrovascular incidents. The syndrome shares features with Dide-Botcazo syndrome and dates back to Roman times. Its causes range from strokes to rare conditions like multiple sclerosis exacerbation. Accurate diagnosis involves considering clinical presentations and imaging studies, distinguishing AS from similar conditions.

CONCLUSION

This comprehensive review sheds light on AS's complex landscape, emphasizing diverse etiologies, clinical features, and treatment options. Tailored treatments aligned with individual causes are crucial. The study's findings caution against blanket anticoagulation therapy, suggesting a nuanced approach. Further research is pivotal to refine diagnostics and optimize care for AS individuals.

Delirium in Acute Stroke: A Review

Background

Delirium is a complex neuropsychiatric syndrome characterized by disturbances of consciousness, attention, cognition, and perception. It may be the presenting feature of acute stroke, but more often it complicates the clinical course in the early stage of rehabilitation.

Summary of review

Risk factors for delirium are older age, pre-existing cognitive decline, metabolic disturbances, infections, and polypharmacy. Recognition of delirium in patients with stroke is important because of its association with a longer stay in the hospital, a poor functional outcome, and an increased risk of developing dementia. The diagnosis may be difficult because of the fluctuating course and the neurological deficits that are caused by the stroke. Nonpharmacological preventive measures, early identification, and additional medical intervention are the key measures in the management of delirium after stroke.

Conclusion

This review describes incidence, risk factors, pathophysiology, diagnostic tools, and management of delirium in patients with a recent stroke.

The role of personal biases in the explanation of confabulation

INTRODUCTION

Previous research has demonstrated that motivational forces play an important role in determining the content of confabulation. In particular the content of confabulation has been shown to contain a positive emotional bias. This study investigated the role of personal biases in the confabulations of six patients with diverse aetiologies.

METHOD

Confabulations were elicited with a series of structured interviews. We then compared the patients' confabulations to their actual situations. Further analyses compared confabulations about current (i.e., the postmorbid period) and past (i.e., premorbid events and general life circumstances) events.

RESULTS

Group analysis confirmed a general bias to recall events that were more positive than the reality. However, examination of individual cases revealed that positive biases were not universal. Confabulations about current circumstances showed the positive bias, whereas an emotional bias was not evident in past confabulations.

CONCLUSION

We conclude that motivational forces play a role in determining the content of confabulations but conceive of this role primarily in terms of a need to maintain a consistent self-concept (whether positive or negative) overlaid upon the ease with which an individual can retrieve familiar premorbid daily activities and routines.

Diagnostic yield of cerebral imaging in patients with acute confusion

OBJECTIVE

Acute confusion (AC) is a frequent reason for hospital admission in elderly patients. Although in majority of cases the cause is a systemic disorder (e.g., dehydration or septicaemia), patients are frequently subjected to cerebral imaging. This study was undertaken to find clinical predictors of normal cerebral computed tomography (CCT) or magnetic resonance imaging (MRI) scans in AC.

METHODS

Retrospective study of 294 patients admitted with AC of unknown origin, of whom 178 received cerebral imaging.

RESULTS

The rate of pathological imaging studies was 14%. The best single predictor of a normal brain scan was the absence of focal signs. Patients without focal abnormalities and either fever or dehydration had a probability of 0.96 of having a normal CCT or MRI. In demented patients without focal signs, the predictive value for a normal brain scan was 0.98, and if either patients with drowsiness were excluded or the existence of fever or dehydration was added as a selection criterion, all patients had normal scans.

CONCLUSIONS

Patients with AC without focal signs and with either evidence for a medical aetiology of delirium or prediagnosed dementia are at a very low risk of having focal lesions in their CCT or MRI.

Agitated delirium with posterior cerebral artery infarction

Infarction of the posterior cerebral artery may present only with signs of agitated delirium and an acute confusional state. In the absence of other prominent neurological deficits, this can be easily mistaken for toxic-metabolic encephalopathy, head trauma, post-ictal confusion, or a psychiatric disorder. Appropriate head imaging studies are important to detect an illness that might otherwise be missed and left untreated.

Imagery without perception--a case study of anosognosia for cortical blindness

A patient with complete cortical blindness after bilateral posterior cerebral artery infarctions denied her blindness. Her pretended visual experiences could frequently be traced back to synaesthetic translations of acoustic or tactile perceptions into mental visual images. Possibly, the belief to see resulted from a confusion of mental visual images with real percepts. The patient manifested preserved visual imagery also by correct responses to questions concerning the shapes of letters and the shapes and colours of objects. MRI showed an almost complete destruction of primary visual cortex with sparing of only small remainders of cortex at the occipital tip of the left upper calcarine lip. In the literature there are a few cases of denial of blindness with similarly severe damage to primary visual cortex but none with unequivocal evidence of complete destruction of primary visual cortex. We conclude that severe damage to primary visual cortex is compatible with visual imagery but that there is a possibility that islands of visual cortex must be spared to permit the generation of mental visual images.

Acute confusional state. Don't mistake it for dementia

Acute confusional state is a condition that is commonly encountered in many types of medical practice. Certain patients, especially the elderly, are vulnerable to the disorder, and recognition of this fact can help prevent the development or minimize the severity of the condition. Thorough history taking and evaluation often point to the underlying cause, and attention to general principles of environmental and pharmacologic management can minimize morbidity.