Clinical differences between early‐ and late‐onset social anxiety disorders

Aim: The aim of this study was to elucidate the clinical differences between early‐ and late‐onset social anxiety disorder (SAD) in the Korean population. Methods: Three hundred and eighty‐seven outpatients diagnosed with SAD participated in this study. Confirmation of SAD diagnosis was based on the Mini International Neuropsychiatric Interview. All subjects completed the Liebowitz Social Anxiety Scale and anxiety‐trait‐related scales such as the Anxiety Sensitivity Index, Retrospective Self‐Report of Inhibition, Trait Form of the State‐Trait Anxiety Inventory, and Beck Depression Inventory. Results: The early‐onset group (n = 209) consisted of subjects aged up to 18 years at the time of onset, whereas the late‐onset group (n = 178) consisted of subjects older than 18 years at the time of onset. Early‐onset SAD patients were more likely to have the generalized subtype and to visit clinics with chief complaints other than social anxiety symptoms. They exhibited more severe symptoms and higher behavioural inhibitions. After adjusting for age and symptom severity, behavioural inhibition was the only significant difference between the two groups. The degree of behavioural inhibitions was associated with earlier onset age. Conclusion: Symptom severity and behavioural inhibitions, especially in social/school situations, were clinical characteristics that differentiated between early‐ and late‐onset SAD.     

Reverse Engineering of Biochemical Reaction Networks Using Co-evolution with Eng-Genes

A major challenge when attempting to model biochemical reaction networks within the cell is that the dimensionality can become huge, where a large number of molecular species can be involved even in relatively small networks. This investigation attempts to infer models of these networks using a co-evolutionary algorithm that reverse engineers differential equation models of the target system from time-series data. The algorithm not only estimates the system parameters, but also the symbolic structure of the network. To reduce the problem of dimensionality, the algorithm uses a partitioning method while integrating candidate models in order to decouple system equations. In addition, the conventional evolutionary algorithm has been modified and extended to include a technique called ‘eng-genes’, where candidate models are built up from fundamental mathematical terms derived from knowledge about the target system a priori. This technique essentially focuses the search on more biologically plausible models. The approach is demonstrated on several example reaction networks. The results show that the eng-genes method of limiting the term pool using a priori knowledge improves the convergence of the reverse engineering process compared with the conventional method, resulting in more accurate and transparent models.     

Delayed Unilateral Soft Palate Palsy without Vocal Cord Involvement after Microvascular Decompression for Hemifacial Spasm

Microvascular decompression is a very effective and relatively safe surgical modality in the treatment of hemifacial spasm. But rare debilitating complications have been reported such as cranial nerve dysfunctions. We have experienced a very rare case of unilateral soft palate palsy without the involvement of vocal cord following microvascular decompression. A 33-year-old female presented to our out-patient clinic with a history of left hemifacial spasm for 5 years. On postoperative 5th day, patient started to exhibit hoarsness with swallowing difficulty. Symptoms persisted despite rehabilitation. Various laboratory work up with magnetic resonance image showed no abnormal lesions. Two years after surgery patient showed complete recovery of unitaleral soft palate palsy. Various etiologies of unilateral soft palate palsy are reviewed as the treatment and prognosis differs greatly on the cause. Although rare, it is important to keep in mind that such complication could occur after microvascular decompression.     

Surgical Outcomes and Complications after Occipito-Cervical Fusion Using the Screw-Rod System in Craniocervical Instability

Objective

Although there is no consensus on the ideal treatment of the craniocervical instability, biomechanical stabilization and bone fusion can be induced through occipito-cervical fusion (OCF). The authors conducted this study to evaluate efficacy of OCF, as well as to explore methods in reducing complications.

Methods

A total of 16 cases with craniocervical instability underwent OCF since the year 2002. The mean age of the patients was 51.5 years with a mean follow-up period of 34.9 months. The subjects were compared using lateral X-ray taken before the operation, after the operation, and during last follow-up. The Nurick score was used to assess neurological function pre and postoperatively.

Results

All patients showed improvements in myelopathic symptoms after the operation. The mean preoperative Nurick score was 3.1. At the end of follow-up after surgery, the mean Nurick score was 2.0. After surgery, most patients'' posterior occipito-cervical angle entered the normal range as the pre operation angle decresed from 121 to 114 degree. There were three cases with complications, such as, vertebral artery injury, occipital screw failure and wound infection. In two cases with cerebral palsy, occipital screw failures occurred. But, reoperation was performed in one case.

Conclusion

OCF is an effective method in treating craniocervical instability. However, the complication rate can be quite high when performing OCF in patients with cerebral palsy, rheumatoid arthritis. Much precaution should be taken when performing this procedure on high risk patients.     

Effect of Pulsed Radiofrequency Neuromodulation on Clinical Improvements in the Patients of Chronic Intractable Shoulder Pain

Objective

The aim of this study was to evaluate effect of pulsed radiofrequency (PRF) neuromodulation of suprascpaular nerve (SSN) in patients with chronic shoulder pain due to adhesive capsulitis and/or rotator cuff tear.

Methods

The study included 11 patients suffering from chronic shoulder pain for at least 6 months who were diagnosed with adhesive capsulitis (n=4), rotator cuff tear (n=5), or adhesive capsulitis+rotator cuff tear (n=2) using shoulder magnetic resonance imaging or extremity ultrasonography. After a favorable response to a diagnostic suprascapular nerve block twice a week (pain improvement >50%), PRF neuromodulation was performed. Shoulder pain and quality of life were assessed using a Visual Analogue Scale (VAS) and the Oxford Shoulder Score (OSS) before the diagnostic block and every month after PRF neuromodulation over a 9-month period.

Results

The mean VAS score of 11 patients before PRF was 6.4±1.49, and the scores at 6-month and 9 month follow-up were 1.0±0.73 and 1.5±1.23, respectively. A significant pain reduction (p<0.001) was observed. The mean OSS score of 11 patients before PRF was 22.7±8.1, and the scores at 6-month and 9 month follow-up were 41.5±6.65 and 41.0±6.67, respectively. A significant OSS improvement (p<0.001) was observed.

Conclusion

PRF neuromodulation of the suprascapular nerve is an effective treatment for chronic shoulder pain, and the effect was sustained over a relatively long period in patients with medically intractable shoulder pain.     

Prolonged Corrected QT Interval in Patients with Myotonic Dystrophy Type 1

Background and Purpose

Sudden cardiac death is one of the leading causes of death in patients with myotonic dystrophy type 1 (DM1). It has been proposed that a prolonged QT interval is associated with sudden cardiac death in several neurological diseases, including multiple system atrophy, idiopathic Parkinson''s disease, and diabetic autonomic neuropathy. However, analyses of the corrected QT (QTc) interval in DM1 patients are rare in the literature. The purposes of this study were to determine the association between the QT interval and DM1, and the affecting factors.

Methods

Thirty-nine patients diagnosed with DM1 through genetic testing were enrolled. The QTc interval (calculated using Bazett''s formula: QTc=QT/√RR) was compared between these patients and 39 normal healthy controls. The clinical and laboratory factors affecting QTc interval in the patient group were investigated.

Results

The QTc interval was significantly longer in the DM1 group (411.2±44.7 msec, mean±SD) than in the normal control group (355.6±20.6 msec). Intragroup analysis revealed that a prolonged QTc interval in DM1 patients was associated with being female and older, having a longer disease duration, and exhibiting abnormal electrocardiography findings.

Conclusions

The higher incidence of sudden cardiac death in the DM1 population is associated with the observed prolonged QTc interval in those patients.