Background
Resistance training for leg muscles is recommended for patients with postural tachycardia syndrome (POTS). However, no study has characterized the relationships between orthostatic symptoms, heart rate (HR) increase, and the mass of the lower leg muscle in patients with POTS. We sought to determine the relationships between the mass of the lower leg muscle, HR increase during the head-up tilt (HUT) test, and orthostatic symptoms in patients with POTS.
Methods
We prospectively enrolled 42 patients with POTS who were older than 16 years. The muscle mass was estimated using bioelectrical impedance analysis. We used the International Physical Activity Questionnaire-Short Form to measure self-reported physical activity. All patients were asked to complete the Korean version of the Orthostatic Grading Scale (KOGS).
Results
The HR increased during the HUT test by 38.7±7.88 beats/minutes. Both the HR increase during the HUT test and the total KOGS score were negatively correlated with the total metabolic equivalent of the task. The leg circumference and muscle mass were not correlated with the HR increase during the HUT test or the KOGS score.
Conclusions
The leg circumference and muscle mass were not related to orthostatic symptoms in patients with POTS. Cardiac remodeling or blood volume increase may be responsible for improvement in POTS after physical activity.

Muscle and nerve biopsy may be vital diagnostic tools in various neuromuscular disorders. Since these procedures are invasive, it matters to decide when to perform a biopsy, which muscle or nerve to be selected, and how to interpret the pathologies. This review addresses the indications, methods of biopsies, and also significant pathological findings frequently encountered in muscle and nerve pathology.

Idiopathic orbital myositis is considered as a subgroup of idiopathic orbital inflammatory disease. It is a non-infectious inflammatory disorder primarily affecting the extraocular muscles and causes various eye symptoms including pain, diplopia and limitation of extraocular movement. Cases of isolated ptosis by idiopathic orbital myositis have been very rarely described in the literature. We report a patient who developed unilateral painless ptosis caused by idiopathic orbital myositis. A 52-year-old man presented with drooping of the right eyelid for 3 days. There was no history of headache, double vision or any other complaints. Neurological examination revealed right ptosis without pupil and extraocular muscles involvement. Repetitive nerve stimulation test was normal. Ptosis did not improve after the neostigmine injection. Magnetic resonance imaging scan showed asymmetric enlargement of right superior rectus/levator palpebrae superioris muscle complex and medial rectus muscle. Ptosis resolved dramatically after oral corticosteroid therapy. Isolated unilateral ptosis can be caused by various etiologies. Idiopathic orbital myositis should be considered in the differential diagnosis of ptosis.

Citations

• Isolated Unilateral Ptosis Caused by Orbital Myositis Involving the Superior Rectus-Levator Muscle
  Woonghee Kim, Eun Hye Jung
  Annals of Optometry and Contact Lens.2022; 21(2): 75.     CrossRef