Real-time laser speckle contrast imaging for intraoperative neurovascular blood flow assessment: animal experimental study

The use of various blood flow control methods in neurovascular interventions is crucial for reducing postoperative complications. Neurosurgeons worldwide use different methods, such as contact Dopplerography, intraoperative indocyanine videoangiography (ICG) video angiography, fluorescein angiography, flowmetry, intraoperative angiography, and direct angiography. However, there is no noninvasive method that can assess the presence of blood flow in the vessels of the brain without the introduction of fluorescent substances throughout the intervention. The real-time laser-speckle contrast imaging (LSCI) method was studied for its effectiveness in controlling blood flow in standard cerebrovascular surgery cases in rat common carotid arteries, such as proximal occlusion, trapping, reperfusion, anastomosis, and intraoperative vessel thrombosis. The real-time LSCI method is a promising method for use in neurosurgical practice. This approach allows timely diagnosis of intraoperative disturbance of blood flow in vessels in cases of clip occlusion or thrombosis. Additionally, LSCI allows us to reliably confirm the functioning of the anastomosis and reperfusion after removal of the clips and thrombolysis in real time. An unresolved limitation of the method is noise from movements, but this does not reduce the value of the method. Additional research is required to improve the quality of the data obtained.

"Unshaved Intradermal Running Suture for Elective Cranial Neurovascular Surgeries"

OBJECTIVE

In this paper, we analyze the experience and propose a method of incision and stitching of the postoperative scalp wound without shaving hair in elective neurosurgical interventions.

METHODS

Between January 2021 and May 2022, 44 patients with various neurovascular pathologies were included in the study. The age of the patients varied from 28 to 58 years. All patients underwent elective surgical interventions with intradermal cosmetic sutures without shaving hair. The results of published observational series of neurosurgical patients with unshaved hair were also analyzed.

RESULTS

Treatment of the surgical field, scalp, and incision were performed without shaving hair in 44 cases. The technique of intradermal suture without shaving hair was used in 31 cases of the classical pterional approach, in 11 cases of minipteronal, in 1 case of parasagittal, and in 1 case of retrosigmoid suboccipittal approaches. The mean age of the patients was 47.5 years (±8.82). The average length of stay in the clinic was 8.02 days (±2.04). The sutures were removed on the fifth-eighth day. All cases were operated on for elective neurovascular interventions: aneurysms without rupture (95.4%), arteriovenous malformations (2.3%), and cavernous angiomas (2.3%). All but one patient (2.3%) had no wound complications-the suture ruptured at the stage of its removal from the skin.

CONCLUSIONS

Our results also show that the use of a nonresorbable intradermal suture combined with hair preservation does not affect the risk of infection.

Laser Speckle Contrast Imaging in Neurosurgery: A Systematic Review

BACKGROUND

Intraoperative study of blood flow in the brain vessels is among the most critical topics of modern neurosurgery. One of the promising methods for intraoperative monitoring of blood flow is laser speckle contrast imaging (LSCI). This systematic review aims to analyze the experience of using intraoperative LSCI in neurosurgical interventions.

METHODS

The literature search was carried out in the PubMed and Web of Science databases using the keywords "Laser-Speckle," "Laser Speckle," "Laser speckle contrast imaging," and "LSCI." We allowed the search to include the following criteria: 1) publication in the English language, 2) full access to the article, 3) information about the method of treatment, and 4) the results presented for at least one patient.

RESULTS

The initial search resulted in the detection of 508 publications, of which 476 were eliminated during the initial assessment of titles and abstracts. Two more articles were excluded due to the lack of data in the English language. Twenty articles were found to be focused on nonhuman studies and therefore were excluded. In three more studies treatment of non-neurosurgical patients was reported. The final analysis included 8 articles with 102 patients overall.

CONCLUSIONS

LSCI is a promising intraoperative method for intraoperative cerebral blood flow assessing. This method offers several advantages over other modalities. The experience of use is limited to a small number of case series. Further investigation of the method and its implementation in clinical practice is needed.

Spinal dural cerebrospinal fluid fistula as a cause of spontaneous intracranial hypotension syndrome: Diagnosis and surgical treatment

Spontaneous intracranial hypotension (SIH) syndrome most often occurs following a cerebrospinal fluid (CSF) fistula that develops in the spinal space. Neurologists and neurosurgeons lack an understanding of the pathophysiology and diagnosis of this disease, which can make timely surgical care difficult. With the correct diagnostic algorithm, it is possible to identify the exact location of the liquor fistula in 90% of cases; subsequent microsurgical treatment can save the patient from the symptoms of intracranial hypotension and restore the ability to work. Female patient, 57 years old, was admitted with SIH syndrome. Magnetic resonance imaging (MRI) of the brain with contrast confirmed signs of intracranial hypotension. Computed tomography (CT) myelography was performed to pinpoint the location of the CSF fistula. The diagnostic algorithm and successful microsurgical treatment of a patient with spinal dural CSF fistula at the Th3-4 level using a posterolateral transdural approach. The patient was discharged on day 3 after the surgery when these complaints regressed completely. At the control examination of the patient 4 months postoperatively, there were no complaints. Identification of the cause and location of spinal the CSF fistula is a complex process that requires several stages of diagnosis. Examination of the entire back with MRI, CT myelography, or subtraction dynamic myelography is recommended. Microsurgical repair of a spinal fistula is an effective method for the treatment of SIH. The posterolateral transdural approach is effective in the repair of a spinal CSF fistula located ventrally in the thoracic spine.

The Prediction of Functional Outcome After Microsurgical Treatment of Unruptured Intracranial Aneurysm Based on Machine Learning

Our study aimed to create a machine learning model to predict patients' functional outcomes after microsurgical treatment of unruptured intracranial aneurysms (UIA). Data on 615 microsurgically treated patients with UIA were collected retrospectively from the Electronic Health Records at N.N. Burdenko Neurosurgery Center (Moscow, Russia). The dichotomized modified Rankin Scale (mRS) at the discharge was used as a target variable. Several machine learning models were utilized: a random forest upon decision trees (RF), logistic regression (LR), support vector machine (SVM). The best result with F1-score metric = 0.904 was produced by the SVM model with a label-encode method. The predictive modeling based on machine learning might be promising as a decision support tool in intracranial aneurysm surgery.