Elective paratracheal neck dissection for lateral metastases from papillary carcinoma of the thyroid: Is it indicated?

BACKGROUND: Therapeutic paratracheal neck dissection for patients with papillary carcinoma of the thyroid is standard treatment. Its use as an elective procedure is controversial. METHODS: Thirty-seven patients with papillary carcinoma of the thyroid and evidence of positive adenopathy at levels II-V underwent selective neck dissection and elective/therapeutic paratracheal neck dissection. Results of preoperative ultrasonography of the neck were compared with the dissection specimens. RESULTS: Morbidity of the surgical procedure was minimal (1 permanent hypocalcemia). All specimens showed metastases from papillary thyroid carcinoma: 100% (37/37) in the jugular chain of lymphatics and 83.7% (31/37) in the paratracheal region. The rate of occult (negative physical examination and ultrasonography) metastases in the paratracheal region in the presence of metastases in the ipsilateral jugular chain was 83.3% (20/24). CONCLUSION: The high rate of occult metastases in the paratracheal region and the low rate of surgical morbidity speak in favor of elective paratracheal neck dissection in patients with metastatic papillary carcinoma of the thyroid.     

Development of the Korea-Polyenvironmental Risk Score for Psychosis

Objective Comprehensive understanding of polyenvironmental risk factors for the development of psychosis is important. Based on a review of related evidence, we developed the Korea Polyenvironmental Risk Score (K-PERS) for psychosis. We investigated whether the K-PERS can differentiate patients with schizophrenia spectrum disorders (SSDs) from healthy controls (HCs). Methods We reviewed existing tools for measuring polyenvironmental risk factors for psychosis, including the Maudsley Environmental Risk Score (ERS), polyenviromic risk score (PERS), and Psychosis Polyrisk Score (PPS). Using odds ratios and relative risks for Western studies and the “population proportion” (PP) of risk factors for Korean data, we developed the K-PERS, and compared the scores thereon between patients with SSDs and HCs. In addition, correlation was performed between the K-PERS and Positive and Negative Syndrome Scale (PANSS). Results We first constructed the “K-PERS-I,” comprising five factors based on the PPS, and then the “K-PERS-II” comprising six factors based on the ERS. The instruments accurately predicted participants’ status (case vs. control). In addition, the K-PERS-I and -II scores exhibited significant negative correlations with the negative symptom factor score of the PANSS. Conclusion The K-PERS is the first comprehensive tool developed based on PP data obtained from Korean studies that measures polyenvironmental risk factors for psychosis. Using pilot data, the K-PERS predicted patient status (SSD vs. HC). Further research is warranted to examine the relationship of K-PERS scores with clinical outcomes of psychosis and schizophrenia.     

Disruption of communication between peripheral and central trigeminovascular neurons mediates the antimigraine action of 5HT 1B/1D receptor agonists

Triptans are 5HT(1B/1D) receptor agonists commonly prescribed for migraine headache. Although originally designed to constrict dilated intracranial blood vessels, the mechanism and site of action by which triptans abort the migraine pain remain unknown. We showed recently that sensitization of peripheral and central trigeminovascular neurons plays an important role in the pathophysiology of migraine pain. Here we examined whether the drug sumatriptan can prevent and/or suppress peripheral and central sensitization by using single-unit recording in our animal model of intracranial pain. We found that sumatriptan effectively prevented the induction of sensitization (i.e., increased spontaneous firing; increased neuronal sensitivity to intracranial mechanical stimuli) in central trigeminovascular neurons (recorded in the dorsal horn), but not in peripheral trigeminovascular neurons (recorded in the trigeminal ganglion). After sensitization was established in both types of neuron, sumatriptan effectively normalized intracranial mechanical sensitivity of central neurons, but failed to reverse such hypersensitivity in peripheral neurons. In both the peripheral and central neurons, the drug failed to attenuate the increased spontaneous activity established during sensitization. These results suggest that neither peripheral nor central trigeminovascular neurons are directly inhibited by sumatriptan. Rather, triptan action appears to be exerted through presynaptic 5HT(1B/1D) receptors in the dorsal horn to block synaptic transmission between axon terminals of the peripheral trigeminovascular neurons and cell bodies of their central counterparts. We therefore suggest that the analgesic action of triptan can be attained specifically in the absence, but not in the presence, of central sensitization.