Neuropsychological manifestations in a case of bilateral thalamic infarction

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.

Diagnosis and management of cerebral venous thrombosis: a statement for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND

The purpose of this statement is to provide an overview of cerebral venous sinus thrombosis and to provide recommendations for its diagnosis, management, and treatment. The intended audience is physicians and other healthcare providers who are responsible for the diagnosis and management of patients with cerebral venous sinus thrombosis.

METHODS AND RESULTS

Members of the panel were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and represent different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 1966 and used the American Heart Association levels-of-evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee.

CONCLUSIONS

Evidence-based recommendations are provided for the diagnosis, management, and prevention of recurrence of cerebral venous thrombosis. Recommendations on the evaluation and management of cerebral venous thrombosis during pregnancy and in the pediatric population are provided. Considerations for the management of clinical complications (seizures, hydrocephalus, intracranial hypertension, and neurological deterioration) are also summarized. An algorithm for diagnosis and management of patients with cerebral venous sinus thrombosis is described.

Cognitive, affective and behavioural disturbances following vascular thalamic lesions: a review

During the last decades, many studies have shown that the thalamus is crucially involved in language and cognition. We critically reviewed a study corpus of 465 patients with vascular thalamic lesions published in the literature since 1980. 42 out of 465 (9%) cases with isolated thalamic lesions allowed further neurocognitive analysis. On the neurolinguistic level, fluent output (=31/33; 93.9%), normal to mild impairment of repetition (=33/35; 94.3%), mild dysarthria (=8/9; 88.9%) and normal to mild impairment of auditory comprehension (=27/34; 79.4%) were most commonly found in the group of patients with left and bilateral thalamic lesions. The taxonomic label of thalamic aphasia applied to the majority of the patients with left thalamic damage (=7/11; 63.6%) and to one patient with bithalamic lesions (=1/1). On the neuropsychological level, almost 90% of the left thalamic and bithalamic patient group presented with amnestic problems, executive dysfunctions and behaviour and/or mood alterations. In addition, two thirds (2/3) of the patients with bilateral thalamic damage presented with a typical cluster of neurocognitive disturbances consisting of constructional apraxia, anosognosia, desorientation, global intellectual dysfunctioning, amnesia, and executive dysfunctions associated with behaviour and/or mood alterations. Our study supports the long-standing view of a 'lateralised linguistic thalamus' but restates the issue of a 'lateralised cognitive thalamus'. In addition, critical analysis of the available literature supports the view that aphasia following left or bithalamic damage constitutes a prototypical linguistic syndrome.

Transient global amnesia may be caused by cerebral vein thrombosis

Transient global amnesia (TGA) is a disorder of unknown aetiology, characterized by sudden loss of anterograde memory, in the absence other neurological signs or symptoms, followed by complete recovery in less than 24h. Precipitating actions such as strenuous physical activity or valsalva-like manoeuvres are frequently reported. Since first described in 1958, by Fisher and Adams, the possible pathophysiology has undergone much speculation. Nonconvulsive epileptic seizures, migraine, paradoxical embolism thorough a patent foramen ovale, and transient ischemic attacks have been proposed as potential mechanisms. One of the latest hypotheses is that venous congestion causes either ischemia or induces spreading depression in the medial temporal lobes. It has been demonstrated that retrograde flow in the internal jugular veins occurs more frequently during valsalva manoeuvres in TGA patients than in controls, supporting a dysfunctional venous circulation as part of the pathogenesis. However, earlier hypotheses typically fail to explain the relatively low recurrence rate of TGA, lack of comorbidity and the relation to precipitating events. If cerebral venous hypertension was the solely cause of TGA it would presumably be much more common with very high recurrence rates among those predisposed of the condition. Structural changes observed in MRI and SPECT studies along with reports of mild cognitive impairment lasting much longer than the amnestic episodes, indicate that TGA is less transient and perhaps somewhat less benign than earlier believed. Many cases of TGA seem to be associated with factors of increased risk of cerebral venous thrombosis, such as polycythemia, antiphospholipid antibodies, venous hypertension, female sex and more. We suggest that most cases of TGA may be due to small thrombi in the deep cerebral venous system. Small venous thrombi may difficult to visualize even when using modern imaging technology. Further studies of TGA patients with for example blood analysis of D-dimer together with MR venography or CT venography could be done to evaluate this new hypothesis.