Transcranial direct electrical stimulation for hand function in a stroke patient with severe upper limb paralysis due to lenticulostriate artery occlusion: a case report

Background Transcranial direct current stimulation, a therapeutic modality to modulate the excitability of injured and uninjured brain hemispheres in stroke patients, is expected to be effective in treating upper limb paralysis. We describe the use of transcranial direct current stimulation to improve the function and frequency of use of the paralyzed hand of a patient with lenticulostriate artery occlusion. Case presentation A Japanese man in his fifties developed a left internal hindfoot perforator branch infarction owing to lenticulostriate artery occlusion, and presented with severe right upper and lower limb paralysis. Multiple interventions for the paralyzed hand, primarily robot therapy, did not noticeably change his hand function or frequency of use in daily life. Therefore, transcranial direct current stimulation was used in combination with upper limb functional exercises for 20 minutes a day, five times a week, for 6 weeks. Consequently, scores for the hand items of the Fugl–Meyer Assessment of the upper extremities improved, and pain and subluxation around the shoulder joint were reduced. Furthermore, the frequency of use and the quality of movement of the paralyzed hand were improved. Conclusions Upper limb functional training and transcranial direct current stimulation improved the function and frequency of use of the paralyzed hand in a stroke patient with severe upper limb paralysis, suggesting that this combined intervention could effectively improve hand function in patients with severe upper limb paralysis.

Perivascular (Virchow–Robin) spaces

Perivascular spaces; also known as the Virchow-Robin Spaces, they are pleurally lined, interstitial fluid-filled areas that surround certain blood vessels in various organs, especially the perforating arteries in the brain, with an immunological function. Dilated perivascular spaces are divided into three types. The first of these is on the lenticulostriate artery, the second is in the cortex following the path of the medullary artery, and the third is in the midbrain. Perivascular spaces can be detected as areas of dilatation on MR images. Although a limited number of perivascular spaces can be seen in a normal brain, the increase in the number of these spaces has been associated with the incidence of various neurodegenerative diseases. Different theories have been suggested about the tendency of the perivascular spaces to expand. Current theories include mechanical trauma due to cerebrospinal fluid pulsing, elongation of penetrating blood vessels, unusual vascular permeability, and increased fluid exudation. In addition, the brain tissue atrophy that occurs with aging; It is thought to contribute to the widening of perivascular spaces by causing shrinkage of arteries, altered arterial wall permeability, obstruction of lymphatic drainage pathways and vascular demyelination. It is assumed that the clinical significance of the dilation tendencies of the perivascular spaces is based on shape change rather than size. These spaces have been mostly observed in brain regions such as corpus callosum, cingulate gyrus, dentate nucleus, substantia nigra and various arterial basins including lenticulostriate artery and mesencephalothalamic artery. In conclusion, when sections are taken on MR imaging, it is possible that perivascular spaces may be confused with microvascular diseases and some neurodegenerative changes. In addition, perivascular spaces can be seen without pathological significance. Therefore, it would be appropriate to investigate the etiological relationship by evaluating the radiological findings and clinical picture together.

Partially thrombosed middle cerebral artery-lenticulostriate artery aneurysm with native radiological examinations suggesting proximal lenticulostriate artery aneurysm: A case report

Background: Preservation of the lenticulostriate artery (LSA) is crucial. LSAs usually cannot be spared with LSA aneurysms, when surgical clipping/excision or endovascular embolization of the LSA itself is performed. On the other hand, the LSA should be separated and preserved for proximal middle cerebral artery (M1)-LSA aneurysms. Case Description: We report a case of M1-LSA aneurysm with native radiological examinations suggesting LSA aneurysm. The highlight of this unusual case was that during surgery, the aneurysm orifice was almost covered with thrombus and blood flow in an aneurysm that appeared separate from M1. Partial thrombectomy-clip reconstruction was performed, and M1 and LSAs were well preserved. Conclusion: Even with currently developed radiological modalities, thrombosed intracranial aneurysms may be misdiagnosed, depending on intraluminal flow conditions. Intraoperative findings from craniotomy sometimes contribute to a better understanding of the pathophysiology and decisions on appropriate treatment strategy.

Early Thrombectomy Protects the Internal Capsule in Patients With Proximal Middle Cerebral Artery Occlusion

Background and Purpose: Proximal middle cerebral artery (MCA) occlusions impede blood flow to the noncollateralized lenticulostriate artery territory. Previous work has shown that this almost inevitably leads to infarction of the dependent gray matter territories in the striate even if perfusion is restored by mechanical thrombectomy. Purpose of this analysis was to evaluate potential sparing of neighboring fiber tracts, ie, the internal capsule. Methods: An observational single-center study of patients with proximal MCA occlusions treated with mechanical thrombectomy and receiving postinterventional high-resolution diffusion-weighted imaging was conducted. Patients were classified according to internal capsule ischemia (IC+ versus IC−) at the postero-superior level of the MCA lenticulostriate artery territory (corticospinal tract correlate). Associations of IC+ versus IC− with baseline variables as well as its clinical impact were evaluated using multivariable logistic or linear regression analyses adjusting for potential confounders. Results: Of 92 included patients with proximal MCA territory infarctions, 45 (48.9%) had an IC+ pattern. Longer time from symptom-onset to groin-puncture (adjusted odds ratio, 2.12 [95% CI, 1.19–3.76] per hour), female sex and more severe strokes were associated with IC+. Patients with IC+ had lower rates of substantial neurological improvement and functional independence (adjusted odds ratio, 0.26 [95% CI, 0.09–0.81] and adjusted odds ratio, 0.25 [95% CI, 0.07–0.86]) after adjustment for confounders. These associations remained unchanged when confining analyses to patients without ischemia in the corona radiata or the motor cortex and here, IC+ was associated with higher National Institutes of Health Stroke Scale motor item scores (β, +2.8 [95% CI, 1.5 to 4.1]) without a significant increase in nonmotor items (β, +0.8 [95% CI, −0.2 to 1.9). Conclusions: Rapid mechanical thrombectomy with successful reperfusion of the lenticulostriate arteries often protects the internal capsule from subsequent ischemia despite early basal ganglia damage. Salvage of this eloquent white matter tract within the MCA lenticulostriate artery territory seems strongly time-dependent, which has clinical and pathophysiological implications.