Antithrombotic Management After Intracranial Hemorrhage.

PURPOSE OF REVIEW: Intracranial hemorrhage remains one of the most feared acute neurological emergencies. However, apart from the acute management, secondary risk factor management and prevention of ischemic events remains ambiguous. We present a thorough review of the current data available regarding management of antithrombotics after intracranial hemorrhage. RECENT FINDINGS: The most robust evidence comes from the investigators of the RESTART trial which reassured the safety of resuming antiplatelet therapy after ICH, namely in patients with prior indication and treatment with antithrombotics. We conclude that based on available data, the risk of recurrent ICH is probably too small to exceed the found benefits of antiplatelet therapy in the secondary prevention of ischemic vascular disease.

MTHFR Gene Mutations Correlate with White Matter Disease Burden and Predict Cerebrovascular Disease and Dementia.

The incidence of dementia is on the rise and expected to continue to increase in the foreseeable future. Two of the most common subtypes of dementia are Alzheimer's subtype and vascular dementia. Hyperhomocysteinemia has been shown to serve as a risk factor for dementia due to an associated blood-brain barrier dysfunction and subsequent small-vessel disease pathology. There are varying causes for hyperhomocysteinemia, including genetic and dietary, among others. We highlight the importance of identifying hyperhomocysteinemia as a potential etiologic and therapeutic target for the most common subtypes of dementia.

Acute Supratentorial Ischemic Stroke with Ipsilateral Hemiparesis: Pathomechanism and Management Challenges.

BACKGROUND: Supratentorial stroke manifesting as ipsilateral hemiparesis is rare. Multiple pathophysiologic mechanisms are possible for this unusual phenomenon and has been previously described. Its implication in therapeutic decision making in a patient with an acute emergent condition has never been discussed. We describe our experience with a patient with this unusual presentation. CASE DESCRIPTION: A 44-year-old woman presented with acute-onset right hemiparesis and left facial weakness. Evaluation with computed tomography angiography showed right M3 segment occlusion. Her National Institutes of Health Stroke Scale score on arrival was 9. Urgent magnetic resonance imaging was performed, which showed ongoing ischemia in the right frontotemporal cortex. She underwent endovascular thrombectomy, and complete revascularization was achieved. Postoperatively, the patient experience complete neurologic recovery. Further diffusion tractography imaging showed near-complete nondecussation of corticospinal fibers. CONCLUSIONS: Discordance between clinical and initial computed tomography angiography findings in a patient with acute ischemic stroke poses a management challenge. Additional imaging to correlate clinical findings in equivocal cases may help in decision making but may significantly delay intervention, and therefore its utility during the short therapeutic window period needs careful consideration. Considering the risks and benefits, timely intervention should be balanced judiciously against appropriate intervention to achieve a positive patient outcome.

Optical coherence tomography of the optic nerve head detects acute changes in intracranial pressure.

We aimed to determine if there are measurable objective changes in the optic nerve head (ONH) immediately after cerebrospinal fluid (CSF) drainage in a prospective case-series of five patients undergoing a clinically indicated lumbar puncture (LP) for diagnosis of idiopathic intracranial hypertension. A Cirrus high-definition optical coherence tomography machine (Carl Zeiss Meditec, Dublin, CA, USA) was used to acquire images in the lateral decubitus position. Optic disc cube and high-definition line raster scans centered on the ONH were obtained immediately before and after draining CSF, while the patient maintained the lateral decubitus position. Measured parameters included retinal nerve fiber layer (RNFL) thickness, peripapillary retinal pigment epithelium/Bruch's membrane (RPE/BM) angulation, transverse neural canal diameter (NCD) and the highest vertical point of the internal limiting membrane from the transverse diameter (papillary height). The mean (±standard deviation) opening and closing CSF pressures were 34.3±11.8 and 11.6±3.3cmH2O, respectively. Mean RNFL thickness (pre LP: 196±105µm; post LP: 164±77µm, p=0.1) and transverse NCD (pre LP: 1985±559µm; post LP: 1590±228µm, p=2.0) decreased in all subjects, but with non-significant trends. The RPE/BM angle (mean change: 5.8±2.0degrees, p=0.003) decreased in all subjects. A decrease in papillary height was seen in three of five subjects (mean: pre LP: 976±275µm; post LP: 938±300µm, p=0.9). Our results show a measurable, objective change in the ONH after acute lowering of the lumbar CSF pressure, suggesting a direct link between the lumbar subarachnoid space and ONH regions, and its potential as a non-invasive method for monitoring intracranial pressures.

Marked olfactory impairment in idiopathic intracranial hypertension.

OBJECTIVE: Many long-duration astronauts develop signs of elevated intracranial pressure and have neuro-ophthalmological findings similar to idiopathic intracranial hypertension (IIH) patients. Some also present with nasal congestion and subjective olfactory impairment. We prospectively evaluated olfactory function in IIH patients and the effect of 6° head-down tilt, which simulates the headward fluid shifting in microgravity, as spaceflight analogues. DESIGN: Olfaction was tested for all subjects in upright and 6° head-down tilt positions using two different measures: University of Pennsylvania Smell Identification Test and Olfactory Threshold Sniffin' Sticks with phenylethyl alcohol. RESULTS: IIH patients (n=19) had significant impairment on both olfactory measures compared with matched controls (n=19). The olfactory threshold dilution levels were 9.07 (95% CI 1.85 to 5.81) and 3.83 (95% CI 7.04 to 11.10), p=0.001, and smell identification scores were 35.61 (95% CI 34.03 to 37.18) and 32.47 (95% CI 30.85 to 34.09), p=0.008, for control and IIH subjects, respectively. The threshold detection was mildly impaired in head-down tilt compared with upright position in the combined subjects (6.05 (95% CI 4.58 to 7.51) vs 6.85 (95% CI 5.43 to 8.27), p=0.004). CONCLUSIONS: We demonstrated that IIH patients have marked impairment in olfactory threshold levels, out of proportion to smell identification impairment. There was also impairment in olfactory threshold in head-down tilt compared with upright positioning, but not for smell identification. The underlying mechanisms for olfactory threshold dysfunction in IIH patients need further exploration.

Resuscitation great. Luigi Galvani and the foundations of electrophysiology.

Luigi Galvani became one of the greatest scientists of the 18th century with his research and the development of his theory on animal electricity. His work was appreciated by many scientists. Nevertheless, it gave rise to one of the most passionate scientific debates in history when Alessandro Volta postulated that Galvani had confused intrinsic animal electricity with small currents produced by metals. This debate would result in the creation of electrophysiology, electromagnetism, electrochemistry and the electrical battery. Galvani responded to each of the postulated theories of Volta giving irrefutable proof of the involvement of electricity in the contraction of muscles. However, his work was subsequently abandoned and silenced for many years but his ideas and theories were finally confirmed by the creation of new instruments and the interest of new scientists who helped position Galvani as the father of electrophysiology.

Einthoven's string galvanometer: the first electrocardiograph.

Willem Einthoven (1860--1927), known as the creator of the electrocardiograph, won a Nobel Prize in 1924 for his contributions to the field of electrocardiography. He was dedicated to research and learning. In developing the electrocardiograph, Einthoven built on the work of earlier physiologists who had studied the electrical mechanisms of the heart. Each earlier invention proved important by contributing concepts and knowledge that would shape Einthoven's device. Herein, we review the history of the electrocardiograph, with a focus on Willem Einthoven's quest to make the device a practical clinical instrument in the diagnosis of cardiac abnormalities.

Resuscitation great. Willem Einthoven: the development of the human electrocardiogram.

The electrocardiogram is one of the most commonly used diagnostic tools in healthcare. This ingenious device was developed and created in the early 1900s by Willem Einthoven, MD, PhD after studying the mechanisms of electromagnetism and Waller's capillary electrometer. Einthoven dedicated most of his research and clinical activities to improve the early versions of the electrical current recording medical devices. Einthoven's most notable invention was the string galvanometer which we now know as the electrocardiogram. Although the idea of using the string galvanometer as a diagnostic tool faced opposition by scientists and physicians of his time, he remained convinced of the potential of his machine to improve patient care. Einthoven's string galvanometer subsequently became the standard diagnostic tool for recognition and differentiation of heart conditions through the interpretation of cardiac waves, and has become standard practice in the field of resuscitation. In 1924, Einthoven received the Nobel Prize in Medicine for his development of the string galvanometer.