Power of the collective: A review of multimodal internet-based surgical education resources in the 21st century.

Electronic resources have changed surgical education in the 21st century. Resources spanning from digital textbooks to multiple choice question banks, online society meetings, and social media can facilitate surgical education. The COVID pandemic drastically changed the paradigm for education. The ramifications of Zoom lectures and online surgical society meetings will last into the future. Educators and learners can be empowered by the many available electronic resources to enhance surgical training and education.

Accuracy of cytopathology evaluation for resected benign and malignant pancreatic disease.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the preferred method for diagnosing pancreatic masses. While the diagnostic success of EUS-FNA is widely accepted, the actual performance of EUS-FNA is not known. This study sought to define the EUS-FNA accuracy compared with the gold standard, surgically resected specimens. The study was a single institution, retrospective, and chart review of patients with surgically resected pancreatic specimens from 2005 to 2015 with a preoperative EUS-FNA or biliary brushing. Cytological reports were organized from least concerning (i.e., low chance of malignancy) to most concerning (high chance of malignancy) into eight cytologic categories. We identified 741 cytologic cases: 530 EUS-FNA and 211 endoscopic brushings. For EUS-FNA samples, 62.5% of "benign" samples proved to be "benign" on surgical pathology. A cytologic diagnosis of "suspicious for malignancy" or "positive for malignancy" were concordant with a cancer diagnosis on surgical pathology 93.3% and 98.0% of cases, respectively. EUS-FNA proved to be highly reliable at diagnosing malignancy for cytologic samples that were "suspicious" or "positive" for malignancy. Paired with supportive clinical data, these interpretations may be used to justify cancer treatment.

Modulation of brain networks by sumatriptan-naproxen in the inflammatory soup migraine model.

Migraine is a debilitating condition; however, the pharmacological effects on central nervous system networks after successful therapy are poorly understood. Defining this neurocircuitry is critical to our understanding of the disorder and for the development of antimigraine drugs. Using an established inflammatory soup model of migraine-like pathophysiology (N = 12) compared with sham synthetic interstitial fluid migraine induction (N = 12), our aim was to evaluate changes in network-level functional connectivity after sumatriptan-naproxen infusion in awake, conscious rodents (Sprague-Dawley rats). Sumatriptan-naproxen infusion functional magnetic resonance imaging data were analyzed using an independent component analysis approach. Whole-brain analysis yielded significant between-group (inflammatory soup vs synthetic interstitial fluid) alterations in functional connectivity across the cerebellar, default mode, basal ganglia, autonomic, and salience networks. These results demonstrate the large-scale antimigraine effects of sumatriptan-naproxen co-administration after dural sensitization.

Brain network alterations in the inflammatory soup animal model of migraine.

Advances in our understanding of the human pain experience have shifted much of the focus of pain research from the periphery to the brain. Current hypotheses suggest that the progression of migraine depends on abnormal functioning of neurons in multiple brain regions. Accordingly, we sought to capture functional brain changes induced by the application of an inflammatory cocktail known as inflammatory soup (IS), to the dura mater across multiple brain networks. Specifically, we aimed to determine whether IS alters additional neural networks indirectly related to the primary nociceptive pathways via the spinal cord to the thalamus and cortex. IS comprises an acidic combination of bradykinin, serotonin, histamine and prostaglandin PGE2 and was introduced to basic pain research as a tool to activate and sensitize peripheral nociceptors when studying pathological pain conditions associated with allodynia and hyperalgesia. Using this model of intracranial pain, we found that dural application of IS in awake, fully conscious, rats enhanced thalamic, hypothalamic, hippocampal and somatosensory cortex responses to mechanical stimulation of the face (compared to sham synthetic interstitial fluid administration). Furthermore, resting state MRI data revealed altered functional connectivity in a number of networks previously identified in clinical chronic pain populations. These included the default mode, sensorimotor, interoceptive (Salience) and autonomic networks. The findings suggest that activation and sensitization of meningeal nociceptors by IS can enhance the extent to which the brain processes nociceptive signaling, define new level of modulation of affective and cognitive responses to pain; set new tone for hypothalamic regulation of autonomic outflow to the cranium; and change cerebellar functions.

Female migraineurs show lack of insular thinning with age.

Gray matter loss in cortical regions is a normal ageing process for the healthy brain. There have been few studies on the process of ageing of the brain in chronic neurological disorders. In this study, we evaluated changes in the cortical thickness by age in 92 female subjects (46 patients with migraine and 46 healthy controls) using high-field magnetic resonance imaging. The results indicate that in contrast to healthy subjects, migraineurs show a lack of thinning in the insula by age. The functional significance of the lack of thinning is unknown, but it may contribute to the overall cortical hyperexcitability of the migraine brain because the region is tightly involved in a number of major brain networks involved in interoception, salience, nociception, and autonomic function, including the default mode network.

A new electronic diary tool for mapping and tracking spatial and temporal head pain patterns in migraine.

AIM: We present an electronic tool for collecting data on the patterns of migraine headache onset and progression. METHODS: A digitized map consisting of 44 color-coded segments was defined based on previous reports of migraine pain and the distribution of nerves in the face, head and neck. The map was overlaid on a schematic map of the face, head and neck nerves. Thirty-six patients (N = 36, 28 female/eight male), who met ICDH-II criteria for episodic migraine and had headaches for at least three years, identified all regions where pain typically started and how pain spread and subsequently progressed. RESULTS: Consistent with previous findings, throbbing was the most prevalent quality of migraine pain, always present in 70% of patients surveyed. For the 70% of the patients with throbbing pain, the temple was the onset site of throbbing pain, with no significant difference in the laterality of onset site (58.3% on the right vs. 55.6% on the left hemisphere). The tool was able to capture patterns of pain distribution for throbbing and pressure headache pain and also may be used to assess the change in the pattern of the pain distribution as the disease progresses. DISCUSSION: The pain map survey may be a useful tool for recording and tracking the temporal pattern of migraine onset both for clinical and research purposes. The tool could be used to create maps of pain locations on a large population scale and thus will be a very useful tool in correlating the temporal nature of headache symptoms with potential mechanisms of disease evolution.

Pain response measured with arterial spin labeling.

The majority of functional MRI studies of pain processing in the brain use the blood oxygenation level-dependent (BOLD) imaging approach. However, the BOLD signal is complex as it depends on simultaneous changes in blood flow, vascular volume and oxygen metabolism. Arterial spin labeling (ASL) perfusion imaging is another imaging approach in which the magnetically labeled arterial water is used as an endogenous tracer that allows for direct measurement of cerebral blood flow. In this study, we assessed the pain response in the brain using a pulsed-continuous arterial spin labeling (pCASL) approach and a thermal stimulation paradigm. Using pCASL, response to noxious stimulation was detected in somatosensory cortex, anterior cingulate cortex, anterior insula, hippocampus, amygdala, thalamus and precuneus, consistent with the pain response activation patterns detected using the BOLD imaging approach. We suggest that pCASL is a reliable alternative for functional MRI pain studies in conditions in which blood flow, volume or oxygen extraction are altered or compromised.

Neuroimaging of the periaqueductal gray: state of the field.

This review and meta-analysis aims at summarizing and integrating the human neuroimaging studies that report periaqueductal gray (PAG) involvement; 250 original manuscripts on human neuroimaging of the PAG were identified. A narrative review and meta-analysis using activation likelihood estimates is included. Behaviors covered include pain and pain modulation, anxiety, bladder and bowel function and autonomic regulation. Methods include structural and functional magnetic resonance imaging, functional connectivity measures, diffusion weighted imaging and positron emission tomography. Human neuroimaging studies in healthy and clinical populations largely confirm the animal literature indicating that the PAG is involved in homeostatic regulation of salient functions such as pain, anxiety and autonomic function. Methodological concerns in the current literature, including resolution constraints, imaging artifacts and imprecise neuroanatomical labeling are discussed, and future directions are proposed. A general conclusion is that PAG neuroimaging is a field with enormous potential to translate animal data onto human behaviors, but with some growing pains that can and need to be addressed in order to add to our understanding of the neurobiology of this key region.