Epidemiological Characteristics of Field Tick-Borne Pathogens in Gwang-ju Metropolitan Area, South Korea, from 2014 to 2018

ObjectivesThe importance of tick-borne diseases is increasing because of climate change, with a lack of long-term studies on tick-borne pathogens in South Korea. To understand the epidemiological characteristics of tick-borne diseases, the monthly distribution of field ticks throughout the year was studied in South Korea between May 2014 and April 2018 in a cross sectional study.MethodsThe presence of various tick-borne pathogens (Rickettsia species, Borrelia species, Anaplasma phagocytophilum) was confirmed by using polymerase chain reaction, to provide information for a prevention strategy against tick-borne pathogenic infections, through increased understanding of the relationship between seasonal variation and risk of infection with Rickettsia species. This was performed using logistic regression analysis (SPSS 20, IBM, USA) of the data obtained from the study.ResultsDuring the study period there were 11,717 ticks collected and 4 species identified. Haemapysalis longicornis was the most common species (n = 10,904, 93.1%), followed by Haemapysalis flava (n = 656, 5.6%), Ixodes nipponensis (n = 151, 1.3%), and Amblyomma testudinarium (n = 6, 0.05%) The results of this cross-sectional study showed that Haemapysalis flava carried a higher risk of transmission of Rickettsia species than other tick species (p < 0.05).ConclusionIn conclusion, due attention should be paid to preventing tick-borne infections in humans whilst engaged in outdoor activities in Spring and Autumn, particularly in places where there is a high prevalence of ticks.

Epidemiological Characteristics of Rodents and Chiggers with Orientia Tsutsugamushi in the Republic of Korea

A survey of rodents and chiggers associated with Orientia tsutsugamushi was conducted in a rural region of the Republic of Korea (Korea) between 2014 and 2018. Overall Apodemus agrarius 15.2% had the highest seropisitive for O. tsutsugamushi, followed by Myodes regulus 11.4%. Monthly risk factors using logistic regression analysis were not associated with O. tsutsugamushi infections in rodents. The overall prevalence rate of O. tsutsugamushi among chiggers was 0.3%. The chigger (Leptotrombidium scutellare) and monthly (October) risk factors were associated with O. tsutsugamushi human infections (P<0.05). Orientia tsutsugamushi infections are endemic in rodents in Korea and people, for example, soldiers who are active outdoors, must employ preventive measures, especially during October (P<0.05). When there are many reports of O. tsutsugamushi infections in Korea. The Boryong strain 85.7% (2/14) was the most common strain detected in chiggers, followed by the Shimokoshi 7.1% (1/14) and Karp 7.1% strains.

Differences in Characteristics and Comorbidity of Cluster Headache According to the Presence of Migraine

BACKGROUND AND PURPOSE: Cluster headache (CH) can present with migrainous symptoms such as nausea, photophobia, and phonophobia. In addition, an overlap between CH and migraine has been reported. This study aimed to determine the differences in the characteristics of CH according to the presence of comorbid migraine. METHODS: This study was performed using data from a prospective multicenter registry study of CH involving 16 headache clinics. CH and migraine were diagnosed by headache specialists at each hospital based on third edition of the International Classification of Headache Disorders (ICHD-3). We interviewed patients with comorbid migraine to obtain detailed information about migraine. The characteristics and psychological comorbidities of CH were compared between patients with and without comorbid migraine. RESULTS: Thirty (15.6%) of 192 patients with CH had comorbid migraine, comprising 18 with migraine without aura, 1 with migraine with aura, 3 with chronic migraine, and 8 with probable migraine. Compared to patients with CH without migraine, patients with CH with comorbid migraine had a shorter duration of CH after the first episode [5.4±7.4 vs. 9.0±8.2 years (mean±standard deviation), p=0.008], a lower frequency of episodic CH (50.0% vs. 73.5%, p=0.010), and a higher frequency of chronic CH (13.3% vs. 3.7%, p=0.033). Psychiatric comorbidities did not differ between patients with and without comorbid migraine. The headaches experienced by patients could be distinguished based on their trigeminal autonomic symptoms, pulsating character, severity, and pain location. CONCLUSIONS: Distinct characteristics of CH remained unchanged in patients with comorbid migraine with the exception of an increased frequency of chronic CH. The most appropriate management of CH requires clinicians to check the history of preceding migraine, particularly in cases of chronic CH.

Falsely Elevated Postvoid Residual Urine Volume in Uterine Myoma

Precise measurement of postvoid residual (PVR) urine volume is a key factor in assessing patients with voiding dysfunction, including those with lower urinary tract problems. The safe and noninvasive ultrasound bladder scan is the preferred mode to measure PVR volume. However, this procedure has a false-positive rate up to 9%, in the presence of ovarian cysts, renal cysts, ascites, or uterine myoma with cystic degeneration. Until now, cystic lesions are known to cause false positivity in ultrasound bladder scanner. However, we encountered falsely-elevated PVR in two cases of non-cystic uterine myomas. We present these cases with detailed radiologic images and volume measurement data.

Seroepidemiological Survey of Zoonotic Diseases in Small Mammals with PCR Detection of Orientia tsutsugamushi in Chiggers, Gwangju, Korea

Serosurveillance for zoonotic diseases in small mammals and detection of chiggers, the vector of Orientia tsutsugamushi, were conducted from September 2014 to August 2015 in Gwangju Metropolitan Area. Apodemus agrarius was the most commonly collected small mammals (158; 91.8%), followed by Myodes regulus (8; 4.6%), and Crocidura lasiura (6; 3.5%). The highest seroprevalence of small mammals for O. tsutsugamushi (41; 26.3%) was followed by hantaviruses (24; 15.4%), Rickettsia spp. (22; 14.1%), and Leptospira (2; 1.3%). A total of 3,194 chiggers were collected from small mammals, and 1,236 of 3,194 chiggers were identified with 7 species of 3 genera: Leptotrombidium scutellare was the most commonly collected species (585; 47.3%), followed by L. orientale (422; 34.1%), Euchoengastia koreaensis (99; 8.0%), L. palpale (58; 4.7%), L. pallidum (36; 2.9%), Neotrombicula gardellai (28; 2.3%), and L. zetum (8; 0.6%). L. scutellare was the predominant species. Three of 1,236 chigger mites were positive for O. tsutsugamushi by PCR. As a result of phylogenetic analysis, the O. tsutsugamushi strain of chigger mites had sequence homology of 90.1-98.2% with Boryong. This study provides baseline data on the distribution of zoonotic diseases and potential vectors for the development of prevention strategies of vector borne diseases in Gwangju metropolitan area.

Phantom Study of a New Laser-Etched Needle for Improving Visibility During Ultrasonography-Guided Lumbar Medial Branch Access With Novices

OBJECTIVE: To compare the visibility and procedural parameters between a standard spinal needle and a new laser-etched needle (LEN) in real-time ultrasonography guided lumbar medial branch access in a phantom of the lumbosacral spine. METHODS: We conducted a prospective single-blinded observational study at a rehabilitation medicine center. A new model of LEN was manufactured with a standard 22-gauge spinal needle and a laser etching machine. Thirty-two inexperienced polyclinic medical students performed ultrasonography-guided lumbar medial branch access using both a standard spinal needle and a LEN with scanning protocol. The outcomes included needle visibility score, needle elapsed time, first-pass success rate, and number of needle sticks. RESULTS: The LEN received significantly better visibility scores and shorter needle elapsed time compared to the standard spinal needle. First-pass success rate and the number of needle sticks were not significantly different between needles. CONCLUSION: A new LEN is expected to offer better visibility and enable inexperienced users to perform an ultrasonography-guided lumbar medial branch block more quickly. However, further study of variables may be necessary for clinical application.

Molecular Epidemiology of Mumps Virus Circulated in Gwangju

The recent mumps epidemic in South Korea has generated a large amount of public concern. This study has attempted to analyze molecular epidemiological changes of mumps virus circulating in Gwangju metropolitan area, South Korea. 953 throat swab samples were collected from patients with parotitis from May 2013 to July 2014. The majority (71.5%) of these cases have occurred in middle or high school students aged from 15 to 19 years. All samples were tested using a reverse transcription polymerase chain reaction (RT-PCR) that targets the short hydrophobic (SH) gene of the virus. Mumps virus SH gene was detected in 39.2% (374/953) of samples. And 82 RT-PCR products were randomly selected for nucleotide sequencing analysis. All of these sequences were determined as genotype I by phylogenetic analysis and showed the highest nucleic acid similarity (99%) with Dg1062/Korea/98 (GenBank accession no. AY309060). These results suggested that appearance of new genotype or genetic variation at the nucleotide level could be ruled out to evaluate main cause of recent mumps outbreak in Gwangju metropolitan area.

Gluteal Compartment Syndrome and Lumbosacral Plexus Injury Associated with Rhabdomyolysis: A Case Report

Gluteal compartment syndrome is a rare disorder which often occurs in conjunction with prolonged immobility after an overdose of sedative. Signs of sciatic nerve compression frequently occur, and rhabdomyolysis may be associated with the syndrome. We recently encountered a patient with lumbosacral plexopathy, complicated by gluteal compartment syndrome. A 42-year-old man presented with weakness and swelling in the right lower extremity and gluteal area after an overdose of antipsychotic drug, accompanied by prolonged immobilization. Serum creatine phosphokinase and urinary myoglobin were markedly elevated, and a T2-weighted pelvis MRI showed hyperintensities and swelling in the gluteal muscles. An electrodiagnosis study showed incomplete lumbosacral plexopathy. The patient received medical treatment and rehabilitation. Six months later, his right lower limb weakness had improved and he could walk independently. Lumbosacral plexus injury with rhabdomyolysis is a rare but debilitating disorder. Therefore, early diagnosis and treatment are crucial for prevention of neurologic deterioration.

Gustatory Change after Sympathetic Ganglion Block in Complex Regional Pain Syndrome Type I Patient: A case report

Some reports provide conclusive evidence of close interactive regulation between the taste receptor and sympathetic nervous system. We report a middle-aged male patient with gustatory change after cervical sympathetic ganglion block (CSGB) who had been suffering from hypersensitivity to sour taste since developing complex regional pain syndrome (CRPS) type 1, diagnosed according to the revised CRPS criteria. Despite receiving two high doses of prednisolone therapy, he experienced the recurrence of CRPS symptoms. We attempted other therapy treatments, including pamidronate intravenous infusion, non-steroidal anti-inflammatory drugs, opioids, tricyclic antidepressants, and CSGB. Following each CSGB administration, the patient reported decreased hypersensitivity to sour-tasting foods, such as kimchi and oranges, with decreased pain and reduction of dysautonomic symptoms. This case demonstrates that overactivation of the sympathetic nervous system may influence sensitivity and regulation of gustatory receptors; therefore, a patient demonstrating CRPS symptoms, including taste alterations, may respond positively to CSGB therapy.

Assessment of Quality of Life in Parents of Childrenwith Cerebral Palsy

OBJECTIVE: To evaluate the quality of life and psychologic status in parents of children with cerebral palsy (CP). METHOD: We studied 94 parents of children with cerebral palsy (case) and 60 parents of normal children (control). The functional level of CP was determined based on the gross motor functional classification system (GMFCS), and type of CP was classified by clinical features. We collected the data through questionnaires obtained from the parents, which consisted of Short Form Health Survey-36 (SF-36), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and Family APGAR score. The data were statistically analyzed. RESULTS: The mean scores of SF-36 in parents of CP children was significantly lower than controls (60.09<67.38, p< 0.001). BDI (p<0.001) and BAI (p=0.002) scores of parents of CP children were significantly higher than control group, and familial APGAR score was lowered in the CP group compared to the control group. There were no differences in the scores of SF-36 in parents according to the severity of CP (p=0.844). CONCLUSION: The quality of life of parents of children with CP was significantly lower than that of control parents. Also psychologic status and familial function were poorer in parents of CP. It is necessary to evaluate and support for parent's psychologic status and quality of life in the comprehensive rehabilitation of CP.

Entrapping of Epidural Catheter after Postoperative Epidural Pain Control: A case report

The insertion of an epidural catheter into the epidural space to control postoperative pain is very common, as the technique is safe, effective and easy to perform. The numbers of documented problems are remarkably few, particularly those encountered during removal of the catheter. A 65-year-old man with stomach cancer was scheduled for a subtotal gastrectomy. The patient requested epidural analgesia for postoperative pain control. The patient was placed in the right decubitus position, and a 17-gauge Arrow Tuohy needle was inserted midline at the T12-L1 vertebral interspace, with the epidural space located using the loss-of-resistance technique. A 19-gauge Arrow Flextip PlusTM epidural catheter was inserted and advanced 5 cm into the epidural space, without difficulty or resistance. Two days after the administration of epidural analgesia, when the effects of local analgesics and opioid had worn off, an attempt was made to remove the catheter in the sitting position. Increased pressure was applied, but the catheter stretched and the wire reinforcement within the catheter began to uncoil. The removal of the epidural catheter was stopped at this point. After three hours, the patient was placed in the right lateral decubitus position, with his legs flexed to his chest, and another attempt to remove the catheter was successful. Herein, a case of difficulty in removing an obstinate epidural catheter is reported.

A Case of Hemichorea of Unknown Cause in a Hemodialysis Patient / 대한신장학회잡지

Uremic patients undergoing hemodialysis (HD) therapy are prone to develop encephalopathy, but the cause is often unclear. Clinical signs of encephalopathy in the uremic patient often overlap with several other affections causing neurological disorders. Chorea or hemichorea occurs very rare, when basal ganglia are injured in HD patients. We hereby report a case of hemichorea of unknown cause in a hemodialysis patients. A 57-year-old diabetic HD patient was presented with sudden onset of right hemichorea. We could not find causes of hemichorea such as hyperglycemia, hepatic failure, drug, hyponatremia, and thiamine deficiency. T1-weighted MRI demonstrated hyperintense lesion limited to the left basal ganglion. Hemichorea disappeared completely 6 months after the onset with support care.

Safety of 'Isolated IVb (Inferior) Resection of the Liver' by Cadaver Dissection

PURPOSE: Healey divided segment IV of the live as the 'superior portion (IVa) ' and the 'inferior portion (IVb) '. On the contrary, Couinaud suggested that there was no useful purpose in dividing segment IV because of several reasons. Our goal is to evaluate the safety of the 'isolated IVb (inferior) resection of the liver' via performing the dissection of cadavers. METHODS: There were ten total cadavers. Cadaver dissection proceeded with respect to the Glissonian pedicle, the portal vein and the bile duct, respectively. The total number of Glissonian pedicles at segment IV was measured. The distance between the origins of the IVa and IVb branches was measured. Additional pedicles that were known to exist at segment IVa were also evaluated. RESULTS: The mean number of Glissonian pedicles in segment IV, IVa, and IVb was 5 (+/-1.3), 1.6 (+/-7), and 3.4 (+/-0.9), respectively. The mean distance between the origins of the IVa and IVb branches was 5.6 mm (+/-3.9 mm). Two of 10 cases had a very short distance between the origins that were considered as having common origin. Additional pedicles were identified at the Lt. main Glissonian pedicle in all the cases (8 cases: 1 each, 2 cases: 2 each). CONCLUSION: Considering the possible existence of a common origin of segment IVa and IVb Glissonian pedicles, there is the risk that the segment IVa will be injured during 'iso lated IVb resection'. Inevitable ligation of the additional pedicle of segment IVa from the Lt. main Glissonian pedicle can be made during the 'isolated IVb resection'. Therefore, we think that 'isolated IVb resection of the liver' can be safe only when the surgeon divides the branches of segment IVb with meticulous preservation of the IVa branches.

Hemodynamic and Preemptive Analgesic Effect of Preoperative Epidural Analgesia during Laparoscopic Hysterectomy / 대한마취과학회지

BACKGROUND: A laparoscopic hysterectomy is gaining popularity on account of its many benefits. The trendelenburg position and pneumoperitoneum necessary for a laparoscopy causes intraoperative hemodynamic fluctuations. The aim of this study was to evaluate the intraoperative hemodynamic and postoperative analgesic effects of preemptive epidural analgesia in a laparoscopic hysterectomy. METHODS: Fifty ASA 1 and 2 patients were randomized to two groups. Nothing was applied to the control group before inducing general anesthesia. In the epidural group, an epidural catheter was inserted through the L2-3 space and 1% lidocaine 10 ml was injected. The blood pressures, heart rates, cardiac outputs, stroke volumes and cardiac indexes were measured using NICO(TM) (Non-Invasive Cardiac Output using partial carbon dioxide rebreathing technique, fast mode, Novametrix Medical Systems Inc, USA) at time before induction (T1), post-intubation (T2), post-insufflation and in the trendelenburg position (T3), post-intubation 10 (T4), 20 (T5), 30 (T6) and 60 minutes (T7), post-exsufflation (T8) and post-neutral position (T9). The pain scores were assessed by the patients using a 100 mm visual analogue scale at 1, 3, 6, 12 and 24 hours postoperatively. RESULTS: There were important differences in the blood pressures, cardiac outputs, stroke volumes and cardiac indexes between the two groups. No significant changes in the heart rate were observed during surgery in either groups. The postoperative pain scores were significantly lower in the epidural group compared with the control group. CONCLUSIONS: Preemptive epidural analgesia produces a more stable hemodynamic state during a laparoscopic hysterectomy and reduces the level of postoperative pain.

Preoperative Glycemic Status Affects the Risk for Acid Aspiration Pneumonia in Elective Cesarean Delivery / 대한마취과학회지

BACKGROUND: Although there are many studies of hypo- or hyperglycemia on gastric function, no studies have been conducted to determine the effect of glycemic status on preoperative gastric contents especially in pregnant women. We investigated the effect of dextrose infusion on preoperative gastric contents and serum gastrin in overfasting pregnant patients. METHODS: After six hours of fasting, forty pregnant patients scheduled for elective cesarean section were randomly assigned to one of two groups to receive either 120 ml/h of 5% dextrose fluid (Dextrose group, n = 20) or same rate of normal saline (Control group) until the induction of anesthesia. Before the start of combined spinal-epidural anesthesia, gastric contents were gently aspirated using a 14-F multiorifice nasogastric tube (Levin tube, Yushin Medical, Shiheung, Korea). Blood samples for the serum gastrin and glucose concentrations were taken. RESULTS: Aspirated gastric pH (2.7 vs. 2.9) and volumes (28.5 vs. 26.5 ml) were similar in the two groups. However, significantly more patients (40%) in the control group were found to be at risk of aspiration syndrome, pH 25 ml, than in the dextrose group (20%). The serum gastrin concentrations of the two groups were not significantly different (32.8 vs. 27.1 pg/ml). Preoperative glucose concentration did not correlate with gastric pH or volumes, but with serum gastrin concentration (tau-b = -0.347, vs. -0.466, P = 0.02). CONCLUSIONS: Preoperative dextrose infusion can decrease the number of patients at risk for pulmonary acid aspiration in overfasting pregnant women undergoing cesarean delivery.

Gastric Volume and Acidity in Pregnant and Non-pregnant Women / 대한마취과학회지

BACKGROUND: Studies of gastric volume and pH during various stages of pregnancy have not confirmed a consistently evaluated volume or acidity, but point out that these patients may be at risk. The aim of this study was to evaluate the volume and acidity of gastric contents in pregnant and non-pregnant patients. METHODS: Thirty pregnant patients scheduled for elective cesarean section under spinal anesthesia (pregnant group) and thirty non-pregnant female patients that underwent gynecologic surgery with general anesthesia (non-pregnant group) were enrolled. Preoperative fasting times and anxiety score, using a visual analogue scale from 0 to 10, were obtained from all patients. After the induction of anesthesia, gastric contents were aspirated gently using a 14-F multiorifice nasogastric tube and syringe. Gastric volume and acidity were measured. RESULTS: The gastric volume (ml) in the pregnant group was 42.8 +/- 35.0 (mean +/- SD, range: 5-130), and in the non-pregnant group 15.8 +/- 11.9 (range: 3-50). The gastric pH in the pregnant group was 2.1 +/- 0.9 (range: 1.3-5.4), and in the non-pregnant group 2.8 +/- 1.7 (range: 1.3-6.5). CONCLUSIONS: We confirm that pregnant women have more acidic and greater gastric volumes than non-pregnant women.

Nail Abnormalities in Alopecia Areata / 대한피부과학회지

BACKGROUND: Nail abnormalities may be associated with alopecia areata and nail abnormalities in alopecia areata are reported to range from 10%-66%. OBJECTIVES: This study investigates the clinical characteristics of nail abnormalities in alopecia areata, such as prevalence depending on sex, age and severities of hair loss. METHODS: Prospective analysis was undertaken by examining the finger nails of 424 alopecia areata patients and the nails of 465 non-alopecic patients were examined as controls. RESULTS: The number of the patients was 424(214 males, 210 females) and their mean age was 28.6 years (range 1-69). Nail abnormalities were noted in 98 (23.1%) out of 424 patients and in 24 (5.1%) out of 465 controls. According to age group, the prevalence of nail abnormalities was high at age under 9(31.7%) and at age of 10-19 (31.6%). The incidence according to severity of hair loss was 20.8% in below 50% of hair loss on scalp, 27.8% in 51%-100% of hair loss on scalp and 41.5% in 51%-100% of hair loss on the scalp and also involving body hair. The Frequent nail abnormalities were leukonychia punctata (8.5%) and pitting nail(8.0%). The other minor nail abnormalities were onychorrhexis, transverse ridging, trachyonychia, melanonychia, abnormality of lunula, onycholysis and koilonychia. CONCLUSIONS: The incidence of nail abnormalities in alopecia areata was significantly higher than in controls and the nail abnormalities were more common in children. The more severe was the degree of alopecia, the higher was the prevalence of nail abnormalities. Leukonychia punctata and pitting nail were frequently found in alopeica areata in Korea. The examination of nail in alopecia areata patients may be helpful in expectation of prognosis.

Comparison of the Effects of Propofol and Isoflurane Anesthesia on Respiratory Gas Exchange during Laparoscopic Cholecystectomy / 대한마취과학회지

BACKGROUND: Introduction of a pneumoperitoneum using CO2 is accompanied by significant alterations in respiratory function and pulmonary gas exchange during laparoscopic cholecystectomy. Previous studies have shown differing results concerning pulmonary gas exchange: a significant decrease of PaO2 was induced with isoflurane. In contrast, no significant changes were observed with propofol. The purpose of the present study was to compare the effects of propofol vs isoflurane on pulmonary gas exchange during general anesthesia for laparoscopic cholecystectomy. METHODS: Forty patients were divided randomly between isoflurane and propofol groups. After induction of anesthesia, ventilation was controlled and intra-abdominal pressure was maintained automatically at 12 mmHg by a CO2 insufflator. After the measuring of baseline values of blood pressure, heart rate, PaO2, PaCO2 and PetCO2 before CO2 insufflation, measurements were also made immediately, 30min after CO2 insufflation and 5 min after CO2 exsufflation. RESULTS: In the isoflurane group, PaCO2, PetCO2, PaO2, and P(a-et)CO2 changed significantly 30 min after CO2 insufflation and 5 min after CO2 exsufflation (P < 0.05). In the propofol group, PaCO2 and PetCO2 increased significantly 30 min after CO2 insufflation and 5 min after CO2 exsufflation (P < 0.05), but PaO2 and P(a-et)CO2 remained constant. When the two groups were compared, there were significant differences in PaO2, PaCO2, PetCO2 and P(a-et)CO2 at 30min after CO2 insufflation and 5 min after CO2 exsufflation (P < 0.05). CONCLUSIONS: These results indicate that during laparoscopic cholecystectomy the PaO2 was significantly lower and PaCO2 and P(a-et)CO2 were significantly higher in the isoflurane group compared with the propofol group.

Metabolic Abnormalities in Patients with Mitochondrial Myopathy Evaluated by In Vivo 31P Magnetic Resonance Spectroscopy

PURPOSE: To investigate the phosphorus metabolic abnormalities in skeletal muscle of patients with mitochondrial myopathy using in vivo 31P magnetic resonance spectroscopy(MRS). MATERIAL AND METHODS: Patients with mitochondrial myopathy(N=10) and normal control subjects (N=10) participated. All in vivo 31P MRS examinations were performed on 1.5T whole-body MRI/MRS system by using an image selected in vivo spectroscopy (ISIS) pulse sequence that provided a 4 X 4 X 4 cm3 volume of interest (VOI) in the right thigh muscle tissue. Peak areas for each phophorus methabolite were measured using a Marquart algorithm. RESULTS: The specific features in patients with mitochondrial myopathy were a significant increase of Pi/PCr ratio (p=0.003) and a significant decrease of ATP/PCr ratio (p=0.004) as compared with normal controls. In particular, the beta-ATP/PCr ratio between controls and patients with mitochondrial myopathy was predominantly altered. CONCLUSIONS: In vivo 31P MRS may be a useful modality in the clinical evaluation of patients with mitochondrial myopathy based on ATP/PCr and Pi/PCr ratios in skeletal muscle tissue and provides a valuable information in further understanding disorders of muscle metabolism.