Transcranial Doppler in the Detection of Cerebral Vasospasm After Subarachnoid Hemorrhage.

Background Transcranial Doppler (TCD) is a simple, noninvasive, nonionizing, portable technique but not widely practiced to detect cerebral vasospasm after subarachnoid hemorrhage (SAH). Objective The aim of this study was to assess the performance of TCD in the detection of cerebral vasospasm in patients with SAH considering CT angiography (CTA) as a gold standard. Methods and material This cross-sectional study included 50 patients with acute SAH admitted to the National Institute of Neurosciences & Hospital (NINS & H), Dhaka, Bangladesh, from February to June 2021. The neurological status, severity of SAH, and initial CT findings were recorded. All patients were screened for cerebral vasospasm with TCD on the 4th, 7th, 10th, and 14th days after the event. Screening of cerebral vasospasm by CTA was done on the 14th day of the event or earlier if TCD suggested vasospasm. Results The mean age of the participants was 51.4 ±13.4 years (mean ± SD), and females were predominant (N=29, 58%). CTA detected cerebral vasospasm in 18 (36%) participants, but TCD could detect it in only 13 (26%) cases. Among the participants who had no vasospasm by CTA, all but one were also found to have no vasospasm by TCD. The agreement between TCD and CTA in detecting cerebral vasospasm was significant (p<0.001, κ=0.726). TCD shows good specificity (96.9%) and positive predictive value (92.8%), but sensitivity (72.2%) and negative predictive value (81.6%) were comparatively lower. Overall, the diagnostic accuracy of TCD in detecting cerebral vasospasm was 88%. Conclusions Although compared to CTA, TCD is a highly specific but less sensitive tool in detecting vasospasm, TCD remains a reliable screening tool for detecting vasospasm following SAH.

The Association of Carotid Plaque Size, Carotid Intima-Media Thickness, Resistive Index, and Pulsatility Index With Acute Ischemic Stroke.

BACKGROUND: Carotid atherosclerosis is an important etiological factor for ischemic stroke. Early carotid lesion detection may prevent further strokes. Doppler ultrasound measures carotid artery blood flow, intima-media thickness, stenosis, plaques, and lumen and wall changes. OBJECTIVE: The objective of this study is to determine the association of carotid plaque size (CPS), carotid intima-media thickness (CIMT), resistive index (RI), and pulsatility index (PI) with acute ischemic stroke. METHODOLOGY: A total of 60 participants were taken, including 30 cases and 30 age- and sex-matched controls. Patients with acute ischemic stroke were included as cases and age- and sex-matched healthy volunteers were included as controls. A carotid duplex study was done in both groups, and the findings were compared. RESULTS: The mean age of the ischemic stroke cases was 63.33±10.79 years; more than half were aged >60 years. Male patients were 73.3% and female patients were 26.7% of the cases. Age and gender were statistically similar (p>0.05) in groups (cases and controls). The plaques were homogenous in 30% of patients, calcified in 26.7%, and mixed in 6.7%. About 36.6% of patients did not have any plaque. CPS was greater among cases than controls in the right and left internal and left common carotid arteries; however, it was not statistically significant (p>0.05). The mean CIMT was 0.79±0.10 mm on the right side and 0.90±0.17 mm on the left side among cases. CIMT was significantly higher in the cases group than in the controls (p<0.05). The mean RI was significantly greater in the left common carotid artery (CCA) among the cases than in the controls (p<0.05). Patients aged over 60 years had significantly higher RI and PI values in the left internal carotid artery (ICA) compared to the younger cases (p<0.05). Smoking history had a significant association with left CCA RI and PI values (p<0.05). However, RI, PI, CPS, and CIMT among cases were similar in different groups like diabetic, non-diabetic, hypertensive, and non-hypertensive patients (p>0.05). CONCLUSION: CIMT was significantly thicker among the patients with ischemic stroke compared to the control group. RI in the left CCA was significantly greater among the stroke patients than in the control group. The age of the patient and smoking habit had an association with RI and PI values. Most of the parameters were found to be significant on the left side, suggesting carotid atherosclerosis may not be symmetrical. A large-scale further study is needed to see the association of these variables with ischemic stroke patients.

Acute Vaccine-Related Encephalopathy and Acute Disseminated Encephalomyelitis (ADEM) After COVID-19 Vaccination: A Case Series From Bangladesh.

There are several reported cases of various neurological adverse effects following the COVID-19 vaccination globally. Acute vaccine-related encephalopathy and acute disseminated encephalomyelitis (ADEM) are included among them. Here we are reporting three cases of ADEM and one case of acute vaccine-related encephalopathy from Bangladesh, which have a possible association with COVID-19 vaccines. All three ADEM cases were elderly; two cases developed symptoms after receiving the second dose of the Sinopharm vaccine, and another case after receiving the second dose of the Sinovac vaccine. We have treated another case of acute vaccine-related encephalopathy following receiving the Moderna vaccine. The patients had features of encephalopathy, including altered consciousness and convulsions. The ADEM cases had MRI (magnetic resonance imaging) brain findings suggestive of ADEM. The other case had normal MRI findings. All the cases were treated with intravenous corticosteroids with full recovery, except for one ADEM patient, who developed aspiration pneumonia and died. Though it is not possible to conclude that COVID-19 vaccination is the causative agent behind these cases, this case series will help to increase awareness regarding the early detection and treatment of these serious adverse effects.

A Case of Swallowing Apraxia Due to Acute Infarct in the Right Precentral Gyrus.

Swallowing apraxia is an intriguing type of apraxia where the patient cannot swallow despite normal neurological examinations including motor, sensory and cerebellar function. In this case report, we present a 60-year-old hypertensive male with swallowing apraxia. There was no attempt to swallow when food materials were given inside his mouth. Although he had normal examination findings including intact lip, tongue, palatal movement, and gag reflex. His cognition was also intact, as he could follow simple commands accurately. Except for a small infarct in the right precentral gyrus in the MRI (Magnetic Resonance Imaging) of the brain, his investigation findings were normal. We treated him with nasogastric feeding, and he gradually recovered over a month. Clinicians should consider swallowing apraxia as one of the clinical features of stroke when patients present with acute onset of swallowing problems. This case report is believed to increase awareness regarding this condition and add valuable information to relevant further studies.

Acute Ischemic Stroke Due to Spontaneous Internal Carotid Artery Dissection in a Human Leukocyte Antigen (HLA) B27 Young Male.

Carotid artery dissection is a significant cause of stroke in young patients. Here, we report a 33-year-old male who presented with right homonymous hemianopia and paresthesia of the right side of the body. Magnetic resonance imaging (MRI) of the brain revealed an acute infarct in the left parieto-occipital region. Magnetic resonance angiography (MRA) and duplex ultrasonography (USG) of the neck vessels suggested the left internal carotid artery dissection as the underlying cause. The patient was a known human leukocyte antigen (HLA) B27 and had a history of a previous attack of uveitis. This case report will raise awareness regarding the possible association of HLA B27 with the dissection of neck vessels.

Cerebrovascular ultrasonography for selecting patients for stroke intervention.

Currently employed diagnostic ultrasonography provides clinically relevant information about cerebral hemodynamic changes in patients with cerebrovascular ischemia. The information thus obtained is often helpful to the physician for establishing or confirming the diagnosis and prognosis as well as in taking appropriate therapeutic decisions. It is associated with a high temporal resolution and can be performed bedside for rapid diagnosis as well as prolonged monitoring. Transcranial Doppler (TCD) ultrasonography is a non-invasive diagnostic modality that provides physiological information regarding various intracranial hemodynamic alterations in patients with cerebrovascular ischemia. Extended applications of TCD are useful in understanding various pathophysiological mechanisms responsible for the clinical manifestations of cerebrovascular ischemia. Thus, TCD is aptly called as the 'stethoscope' of a stroke neurologist. Cerebrovascular ultrasonography is considered as an essential component of a comprehensive stroke center. We have reviewed various recent patents pertaining to the applications of cerebrovascular ultrasonography employed in the selection of stroke patients for various therapeutic interventions.

Acute ischemic stroke: comparison of low-dose and standard-dose regimes of tissue plasminogen activator.

Intravenous tissue plasminogen activator (IV-TPA), administered within 4.5 h of symptom onset, is the only therapeutic agent approved for achieving arterial recanalization in acute ischemic stroke. Current major guidelines recommend the use of a standard dose (0.9 mg/kg bodyweight; maximum 90 mg) of IV-TPA. However, comparable efficacy of IV-TPA was demonstrated in the observational studies from Japan when a lower dose (0.6 mg/kg bodyweight; maximum 60 mg) was used and later approved by the regulatory authorities. Although limited in numbers, considerable variations in the dose of IV-TPA are noted in recent publications from Asia, with variable results and optimal dose of TPA in Asia remains controversial. The authors present a systemic review of the existing literature and compare the efficacy and safety of standard-versus the low-dose IV-TPA therapy in acute ischemic stroke.