Blood supply to the corticospinal tract: A pictorial review with application to cranial surgery and stroke

Assessing informative tract segmentation and nTMS for pre-operative planning

BACKGROUND

Deep learning-based (DL) methods are the best-performing methods for white matter tract segmentation in anatomically healthy subjects. However, tract annotations are variable or absent in clinical data and manual annotations are especially difficult in patients with tumors where normal anatomy may be distorted. Direct cortical and subcortical stimulation is the gold standard ground truth to determine the cortical and sub-cortical lo- cation of motor-eloquent areas intra-operatively. Nonetheless, this technique is invasive, prolongs the surgical procedure, and may cause patient fatigue. Navigated Transcranial Magnetic Stimulation (nTMS) has a well-established correlation to direct cortical stimulation for motor mapping and the added advantage of being able to be acquired pre-operatively.

NEW METHOD

In this work, we evaluate the feasibility of using nTMS motor responses as a method to assess corticospinal tract (CST) binary masks and estimated uncertainty generated by a DL-based tract segmentation in patients with diffuse gliomas.

RESULTS

Our results show CST binary masks have a high overlap coefficient (OC) with nTMS response masks. A strong negative correlation is found between estimated uncertainty and nTMS response mask distance to the CST binary mask.

COMPARISON WITH EXISTING METHODS

We compare our approach (UncSeg) with the state-of-the-art TractSeg in terms of OC between the CST binary masks and nTMS response masks.

CONCLUSIONS

In this study, we demonstrate that estimated uncertainty from UncSeg is a good measure of the agreement between the CST binary masks and nTMS response masks distance to the CST binary mask boundary.

Acute aortic occlusion leading to spinal cord ischemia in a 73-year-old: A case report

Background

Cauda equina syndrome (CES) is typically caused by a compressive etiology from a herniated disk, tumor, or fracture of the spine compressing the thecal sac. Here, we report a CES mimic - acute aortic occlusion (AAO), a rare disease that is associated with high morbidity and mortality. AAO can compromise spinal cord blood supply and leads to spinal cord ischemia.

Case Description

Our patient presented with an acute onset of bilateral lower extremity pain and weakness with bowel/bladder incontinence, a constellation of symptoms concerning for CES. However, on initial imaging, there was no compression of his thecal sac to explain his symptomology. Further, investigation revealed an AAO. The patient underwent an emergent aortic thrombectomy with resolution of symptoms.

Conclusion

AAO can mimic CES and should be considered in one's differential diagnosis when imaging is negative for any spinal compressive etiologies.

The neutrophil-to-lymphocyte ratio is an important indicator correlated to early neurological deterioration in single subcortical infarct patients with diabetes

Background and purpose

This study aimed to investigate the relationship between neutrophil-to-lymphocyte ratio (NLR) and early neurological deterioration (END) among cases suffering from single subcortical infarction (SSI) and diabetes.

Methods

We collected the data of patients with SSI admitted to our hospital between January 2019 and December 2020 retrospectively. A score of ≥2 elevations in overall National Institutes of Health Stroke Scale (NIHSS) score or ≥1 increase in motor NIHSS score in 5-day post-admission was considered END. Furthermore, logistic regression was used to analyze the relationship between NLR and END among SSI cases.

Results

Altogether, we enrolled 235 consecutive SSI cases, of which 53 (22.5%) were diagnosed with END, while 93 (39.5%) were diabetic. In patients with diabetes, the value of NLR increased markedly among the patients with END (median, 3.59; IQR, 2.18–4.84) compared to patients without END (median, 2.64; IQR, 1.89–3.18; P = 0.032). Meanwhile, in patients without diabetes, NLR was not significantly associated with END. In the multivariate analysis, NLR values were positively related to END (adjusted odds ratio (OR), 1.768; 95% CI, 1.166–2.682, P = 0.007) upon adjusting age, SSI type, lesion diameter, initial NIHSS, fasting blood glucose (FBG), 2-h postprandial blood glucose (2hPBG), and estimated glomerular filtration rate (eGFR). The subgroup analysis showed that the relationship between NLR and END was more pronounced in the branch atheromatous disease (BAD) (adjusted OR, 1.819; 95% CI, 1.049–3.153, P = 0.033) and anterior SSI subgroups (adjusted OR, 2.102; 95% CI, 1.095–4.037, P = 0.026).

Conclusion

NLR value was significantly related to END among SSI patients with diabetes and was recognized as an independent factor in predicting the risk of END.