Clinical Validation of Non-Invasive Prenatal Testing for Fetal Common Aneuploidies in 1,055 Korean Pregnant Women: a Single Center Experience

BACKGROUND: Non-invasive prenatal testing (NIPT) using cell-free fetal DNA from maternal plasma for fetal aneuploidy identification is expanding worldwide. The objective of this study was to evaluate the clinical utility of NIPT for the detection of trisomies 21, 18, and 13 of high-risk fetus in a large Korean population. METHODS: This study was performed retrospectively, using stored maternal plasma from 1,055 pregnant women with singleton pregnancies who underwent invasive prenatal diagnosis because of a high-risk indication for chromosomal abnormalities. The NIPT results were confirmed by karyotype analysis. RESULTS: Among 1,055 cases, 108 cases of fetal aneuploidy, including trisomy 21 (n = 57), trisomy 18 (n = 42), and trisomy 13 (n = 9), were identified by NIPT. In this study, NIPT showed 100% sensitivity and 99.9% specificity for trisomy 21, and 92.9% sensitivity and 100% specificity for trisomy 18, and 100% sensitivity and 99.9% specificity for trisomy 13. The overall positive predictive value (PPV) was 98.1%. PPVs for trisomies 21, 18, and 13 ranged from 90.0% to 100%. CONCLUSION: This study demonstrates that our NIPT technology is reliable and accurate when applied to maternal DNA samples collected from pregnant women. Further large prospective studies are needed to adequately assess the performance of NIPT.

Brachial Plexus Injury after Deep Sleep

Lying on the side while falling asleep deeply after drinking or taking a sleeping pill can cause compressive neuropathy. We report a 70-year-old male patient of medial cord of left brachial plexus injury (BPI) after deep sleep. The mechanism of the injury might be compression and stretching of brachial plexus. The electrodiagnostic study was performed and the medial cord lesion of BPI was suggested. The ultrasonography image of compression site revealed the nerve swelling of medial cord of brachial plexus and median nerve at the mid-arm level. Pharmacologic treatment including oral prednisolone and exercise training were prescribed. On 6 months after initial visit, neurologic symptom and pain were improved but mild sequelae was remained.

Indirect Ultrasound Guidance Increased Accuracy of the Glenohumeral Injection Using the Superior Approach: A Cadaveric Study of Injection Accuracy

OBJECTIVE: To investigate whether or not indirect ultrasound guidance could increase the accuracy of the glenohumeral joint injection using the superior approach. METHODS: Twelve shoulders from 7 adult cadavers were anatomically dissected after a dye injection had been performed, while the cadavers were in the supine position. Before the injection, a clinician determined the injection point using the ultrasound and the more internal axial arm rotation was compared to how it was positioned in a previous study. Injection confidence scores and injection accuracy scores were rated. RESULTS: The clinician's confidence score was high in 92% (11 of 12 shoulders) and the injection accuracy scores were 100% (12 of 12 shoulders). The long heads of the biceps tendons were not penetrated. CONCLUSION: Indirect ultrasound guidance and positioning shoulder adducted at 10degrees and internally rotated at 60degrees-70degrees during the superior glenohumeral joint injection would be an effective method to avoid damage to the long head of biceps tendons and to produce a highly accurate injection.

Holmes Tremor After Brainstem Hemorrhage, Treated With Levodopa

Holmes tremor is a rare movement phenomenon, with atypical low-frequency tremor at rest and when changing postures, often related to brainstem pathology. We report a 70-year-old female patient who was presented with dystonic head and upper limb tremor after brainstem hemorrhage. The patient had experienced a sudden onset of left hemiparesis and right facial paralysis. Brain magnetic resonance imaging showed an acute hemorrhage from the brachium pontis through the dorsal midbrain on the right side. Several months later, the patient developed resting tremor of the head and left arm, which was exacerbated by a sitting posture and intentional movement. The tremor showed a regular low-frequency (1-2 Hz) for the bilateral sternocleidomastoid and cervical paraspinal muscles at rest. The patient's symptoms did not respond to propranolol or clonazepam, but gradually improved with levodopa administration. Although various remedies were attempted, overall, the results were poor. We suggest that levodopa might be a useful remedy for Holmes tremor. The curative or relieving effect of the dopaminergic agent in Holmes tremor needs more research.

Electrophysiologic Investigation During Facial Motor Neuron Suppression in Patients With Hemifacial Spasm: Possible Pathophysiology of Hemifacial Spasm: A Pilot Study

OBJECTIVE: To evaluate the pathophysiological mechanism of hemifacial spasm (HFS), we performed electrophysiological examinations, such as supraorbital nerve stimulation with orbicularis oris muscle recording and lateral spread tests, after suppressing the patient's central nervous system by administering intravenous diazepam. METHODS: Six patients with HFS were recruited. Supraorbital nerve stimulation with orbicularis oris muscle recording and the lateral spread test were performed, followed by intravenous application of 10 mg diazepam to achieve facial motor neuron suppression. Subsequently, we repeated the two electrophysiological experiments mentioned above at 10 and 20 minutes after the patients had received the diazepam intravenously. RESULTS: Orbicularis oris muscle responses were observed in all patients after supraorbital nerve stimulation and lateral spread tests. After the diazepam injection, no orbicularis oris muscle response to supraorbital nerve stimulation was observed in one patient, and the latencies of this response were evident as a slowing tendency with time in the remaining five patients. However, the latencies of the orbicularis oris muscle responses were observed consistently in all patients in the lateral spread test. CONCLUSION: Our results suggest that ectopic excitation/ephaptic transmission contributes to the pathophysiological mechanisms of HFS. This is because the latencies of the orbicularis oris muscle responses in the lateral spread test were observed consistently in the suppressed motor neuron in our patients.