Bedside detection of acute epidural hematoma by transcranial sonography in a head-injured patient

Transcranial sonography in the critical patient

Transcranial ultrasonography is a non-invasive, bedside technique that has become a widely implemented tool in the evaluation and management of neurocritically ill patients. It constitutes a technique in continuous growth whose fundamentals (and limitations) must be known by the intensivist. This review provides a practical approach for the intensivist, including the different sonographic windows and planes of insonation and its role in different conditions of the neurocritical patients and in critical care patients of other etiologies.

Establishing proof of concept for sonolucent cranioplasty and point of care ultrasound imaging after posterior fossa decompression for Chiari malformation

BACKGROUND

Evaluation after posterior fossa decompression for Chiari malformation can require repeated imaging, particularly with persistent symptoms. Typically, CT or MRI is used. However, CT carries radiation risk and MRI is costly. Ultrasound is an inexpensive, radiation-free, point-of-care modality that has, thus far, been limited by intact skull and traditional cranioplasty materials. Ultrasound also allows for imaging in different head positions and body postures, which may lend insight into cause for persistent symptoms despite adequate decompression on traditional neutral static CT or MRI. We evaluate safety and feasibility of ultrasound as a post-operative imaging modality in patients reconstructed with sonolucent cranioplasty during posterior fossa decompression for Chiari malformation.

METHODS

Outcomes were analyzed for 26 consecutive patients treated with a Chiari-specific sonolucent cranioplasty. This included infection, need for revision, CSF leak, and pseudomeningocele. Ultrasound was performed point-of-care in the outpatient clinic by the neurosurgery team to assess feasibility.

RESULTS

In eight months mean follow up, there were no surgical site infections or revisions with this novel sonolucent cranioplasty. Posterior fossa anatomy was discernable via transcutaneous ultrasound obtained point-of-care in the clinic setting at follow up visits.

CONCLUSION

We demonstrate proof of concept for ultrasound as a post-operative imaging modality after posterior fossa decompression for Chiari malformation. With further investigation, ultrasound may prove to serve as an alternative to CT and MRI in this patient population, or as an adjunct to provide positional and dynamic information. Use of sonolucent cranioplasty is safe. This technique deserves further study.

First Experience With Postoperative Transcranial Ultrasound Through Sonolucent Burr Hole Covers in Adult Hydrocephalus Patients

BACKGROUND

Managing patients with hydrocephalus and cerebrospinal fluid (CSF) disorders requires repeated head imaging. In adults, it is typically computed tomography (CT) or less commonly magnetic resonance imaging (MRI). However, CT poses cumulative radiation risks and MRI is costly. Ultrasound is a radiation-free, relatively inexpensive, and optionally point-of-care alternative, but is prohibited by very limited windows through an intact skull.

OBJECTIVE

To describe our initial experience with transcutaneous transcranial ultrasound through sonolucent burr hole covers in postoperative hydrocephalus and CSF disorder patients.

METHODS

Using cohort study design, infection and revision rates were compared between patients who underwent sonolucent burr hole cover placement during new ventriculoperitoneal shunt placement and endoscopic third ventriculostomy over the 1-year study time period and controls from the period 1 year before. Postoperatively, trans-burr hole ultrasound was performed in the clinic, at bedside inpatient, and in the radiology suite to assess ventricular anatomy.

RESULTS

Thirty-seven patients with sonolucent burr hole cover were compared with 57 historical control patients. There was no statistically significant difference in infection rates between the sonolucent burr hole cover group (1/37, 2.7%) and the control group (0/57, P = .394). Revision rates were 13.5% vs 15.8% (P = 1.000), but no revisions were related to the burr hole or cranial hardware.

CONCLUSION

Trans-burr hole ultrasound is feasible for gross evaluation of ventricular caliber postoperatively in patients with sonolucent burr hole covers. There was no increase in infection rate or revision rate. This imaging technique may serve as an alternative to CT and MRI in the management of select patients with hydrocephalus and CSF disorders.

Transcranial ultrasonography to detect intracranial pathology: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Transcranial ultrasonography (TCU) can be a useful diagnostic tool in evaluating intracranial pathology in patients with limited or delayed access to routine neuroimaging in critical care or austere settings. We reviewed available literature investigating the diagnostic utility of TCU for detecting pediatric and adult patient's intracranial pathology in patients with intact skulls and reported diagnostic accuracy measures.

METHODS

We performed a systematic review of PubMed^® , Cochrane Library, Embase^® , Scopus^® , Web of Science™, and Cumulative Index to Nursing and Allied Health Literature databases to identify articles evaluating ultrasound-based detection of intracranial pathology in comparison to routine imaging using broad Medical Subject Heading sets. Two independent reviewers reviewed the retrieved articles for bias using the Quality Assessment of Diagnostic Accuracy Studies tools and extracted measures of diagnostic accuracy and ultrasound parameters. Data were pooled using meta-analysis implementing a random-effects approach to examine the sensitivity, specificity, and accuracy of ultrasound-based diagnosis.

RESULTS

A total of 44 studies out of the 3432 articles screened met the eligibility criteria, totaling 2426 patients (Mean age: 60.1 ± 14.52 years). We found tumors, intracranial hemorrhage (ICH), and neurodegenerative diseases in the eligible studies. Sensitivity, specificity, and accuracy of TCU and their 95% confidence intervals were 0.80 (0.72, 0.89), 0.71 (0.59, 0.82), and 0.76 (0.71, 0.82) for neurodegenerative diseases; 0.88 (0.74, 1.02), 0.81 (0.50, 1.12), and 0.94 (0.92, 0.96) for ICH; and 0.97 (0.92, 1.03), 0.99 (0.96, 1.01), and 0.99 (0.97, 1.01) for intracranial masses. No studies reported ultrasound presets.

CONCLUSIONS

TCU has a reasonable sensitivity and specificity for detecting intracranial pathology involving ICH and tumors with clinical applications in remote locations or where standard imaging is unavailable. Future studies should investigate ultrasound parameters to enhance diagnostic accuracy in diagnosing intracranial pathology.

Head to toe ultrasound: a narrative review of experts’ recommendations of methodological approaches

Critical care ultrasonography (US) is widely used by intensivists managing critically ill patients to accurately and rapidly assess different clinical scenarios, which include pneumothorax, pleural effusion, pulmonary edema, hydronephrosis, hemoperitoneum, and deep vein thrombosis. Basic and advanced critical care ultrasonographic skills are routinely used to supplement physical examination of critically ill patients, to determine the etiology of critical illness and to guide subsequent therapy. European guidelines now recommend the use of US for a number of practical procedures commonly performed in critical care. Full training and competence acquisition are essential before significant therapeutic decisions are made based on the US assessment. However, there are no universally accepted learning pathways and methodological standards for the acquisition of these skills.

Therefore, in this review, we aim to provide a methodological approach of the head to toe ultrasonographic evaluation of critically ill patients considering different districts and clinical applications.

Intracranial hemorrhage detected through a craniotomy site with point of care ultrasound

A 60-year-old male presented to the emergency department with acute change in mental status while recovering from a recent hemicraniectomy. During evaluation by the emergency physician, a point-of-care ultrasound (POCUS) was performed using the patient's existing craniectomy site as a sonographic window. Multiple areas of intracranial hemorrhage were visualized on POCUS and head computed tomography scan ultimately requiring urgent neurosurgical intervention. Our case report demonstrates an innovative application of POCUS in the emergency department- setting that has potential to expedite diagnosis and management of life-threatening neurosurgical etiologies, such as hemorrhage and midline shift, in a unique patient population.

Applications of Transcranial Color-Coded Sonography in the Emergency Department

Transcranial color-coded Doppler sonography is a noninvasive bedside ultrasound application that combines both imaging of parenchymal structures and Doppler assessment of intracranial vessels. It may aid in rapid diagnoses and treatment decision making of patients with intracranial emergencies in point-of-care settings. This pictorial essay illustrates the technical aspects and emergency department applications of transcranial color-coded Doppler sonography, and provides some rationale for implementation of this technique into the emergency department practice.

Echography in brain imaging in intensive care unit: State of the art

Transcranial sonography (TCS) is an ultrasound-based imaging technique, which allows the identification of several structures within the brain parenchyma. In the past it has been applied for bedside assessment of different intracranial pathologies in children. Presently, TCS is also used on adult patients to diagnose intracranial space occupying lesions of various origins, intracranial hemorrhage, hydrocephalus, midline shift and neurodegenerative movement disorders, in both acute and chronic clinical settings. In comparison with conventional neuroimaging methods (such as computed tomography or magnetic resonance), TCS has the advantages of low costs, short investigation times, repeatability, and bedside availability. These noninvasive characteristics, together with the possibility of offering a continuous patient neuro-monitoring system, determine its applicability in the monitoring of multiple emergency and non-emergency settings. Currently, TCS is a still underestimated imaging modality that requires a wider diffusion and a qualified training process. In this review we focused on the main indications of TCS for the assessment of acute neurologic disorders in intensive care unit.

Ultrasound-based imaging in neurocritical care patients: a review of clinical applications

OBJECTIVE

To analyze the diagnostic, monitoring, and procedural applications of ultrasound (US) imaging in neurocritical care (NCC) patients.

METHOD

US imaging has been extensively validated in various subset of critically ill patients, but not specifically in the NCC population. We reviewed the clinical applications of US imaging for heart, vascular, brain, and lung evaluation and for possible procedural uses in NCC patients. Major neurosurgical books, journals, testimonials, authors' personal experience, and scientific databases were analyzed.

RESULTS

Cardiac US imaging provides accurate information at NCC arrival to stratify risk factors, including presence of atrial septal defect/patent formen ovale, abnormal ventricular function, or pericardial effusion, and to monitor cardiac anatomy and function during the NCC stay for guiding goal-directed therapy. Vascular US in NCC patients has three especially relevant indications: to screen anatomy and flow in extracranial supra-aortic arteries, to diagnose deep vein thrombosis, and to optimize the safety of central venous catheterization. Brain US has important clinical applications in the NCC, including transcranial Doppler and emerging techniques for cerebral blood flow evaluation with contrast-enhanced US imaging. Lung US, as demonstrated in other intensive care unit patients, provides accurate diagnosis of anatomical and functional abnormalities and enables diagnosis of pleural effusion, pneumothorax, lung consolidation, pulmonary abscess and interstitial-alveolar syndrome, and lung recruitment/derecruitment. US imaging can effectively guide percutaneous tracheostomy.

CONCLUSION

In conclusion, US imaging is an important diagnostic tool that provides real-time information at the bedside to stratify risk, monitor for complications, and guide invasive procedures in NCC patients.

Preliminary Experience of Assessment of Intracranial Lesions by Ultrasound in Multiple Trauma Patients Undergoing Craniectomy

Objective

To explore the feasibility and reliability of B-mode ultrasound for assessment of intracranial lesions in multiple trauma patients who had undergone craniectomy.

Design

ingle-centre study.

Setting

A 16-bed emergency intensive care unit (ICU) in the emergency department of 2nd Affiliated Hospital of Zhejiang University School of Medicine from July 2006 to June 2010.

Methods

We retrospectively analysed 13 multiple trauma patients with severe head injury admitted to the emergency department of 2nd Affiliated Hospital of Zhejiang University School of Medicine. All 13 patients were admitted to the ICU after craniectomy and received mechanical ventilation. Computed tomography (CT) were conducted when patients' consciousness, pupillary size, light reflex changed apparently, or if the bone window tension and the intracranial pressure increased unexpectedly. Head ultrasonography was performed within 2 hours of CT scanning.

Results

Ultrasonography revealed 18 pathological changes in the 13 patients. CT and a second operation helped to identify 23 pathological changes. The results of B-mode ultrasound were compared with those of CT and the coincidence rate was 78.3%, with no significant difference in the diagnosis of delayed haematoma or midline shift (Kappa=0.898, p<0.05).

Conclusions

Transcranial ultrasonography may be a useful tool for monitoring post-operation intracranial lesions in multiple trauma patients with severe head injury. It is an effective supplement to CT.

Usefulness of transcranial echography in patients with decompressive craniectomy: a comparison with computed tomography scan

OBJECTIVE

To assess the agreement between computed tomography and transcranial sonography in patients after decompressive craniectomy.

DESIGN

Prospective study.

SETTING

The medical intensive care unit of a university-affiliated teaching hospital.

PATIENTS

Thirty head-injured patients consecutively admitted to the intensive care unit of "A. Gemelli" Hospital who underwent decompressive craniectomy were studied. Immediately before brain cranial tomography, transcranial ultrasonography was performed.

MEASUREMENTS AND MAIN RESULTS

The mean difference between computed tomography and echography in measuring the dislocation of midline structures was 0.3 ± 1.6 mm (95% confidence interval 0.2-0.9 mm; intraclass correlation coefficient, 0.979; p < .01). An excellent correlation was found between computed tomography and transcranial sonography in assessing volumes of hyperdense lesions (intraclass correlation coefficient, 0.993; p < .01). Lesions that appear hypodense on computed tomography scan were divided in ischemic and late hemorrhagic. No ischemic lesion was localized on echography; a poor correlation was found between computed tomography and echography in assessing the volume of late hemorrhagic lesions (intraclass correlation coefficient, 0.151; p = .53). A quite good correlation between transcranial ultrasonography and computed tomography was found in measuring lateral ventricles width (intraclass correlation coefficient, 0.967; p < .01). Sensitivity and specificity of transcranial ultrasonography in comparison with computed tomography to detect the position of intracranial pressure catheter was 100% and 78%.

CONCLUSIONS

Echography may be a valid option to computed tomography in patients with decompressive craniectomy to assess the size of acute hemorrhagic lesions, to measure midline structures and the width of lateral ventricles, and to visualize the tip of the ventricular catheter.