Dysphagia is a common complication of ischemic stroke and is usually difficult to treat.The mainstay of standard therapy of post-stroke dysphagia(PSD)is effortful swallowing.Since its introduction in 2004,there is inc...Dysphagia is a common complication of ischemic stroke and is usually difficult to treat.The mainstay of standard therapy of post-stroke dysphagia(PSD)is effortful swallowing.Since its introduction in 2004,there is increasing evidence that sur-face electromyography-guided biofeedback training(EMGBT)can enhance the therapeutic effect of standard LE.In this editorial,we comment on the article by Meng et al published in the recent issue of the World Journal of Clinical Cases,which provided evidence that particularly extensive EMGBT with an increased number of sessions is definitively more effective than the standard speech therapy or or-dinary EMGBT.Among the 90 PSD patients with ischemic stroke or intracerebral bleeding,those who underwent EMGBT in more sessions than usual particularly benefited from the approach.It was concluded that EMGBT is more effective than traditional swallowing training in improving dysphagia and swallowing disor-ders as well as hyoid-laryngeal complex movement speed in PSD patients.展开更多
In a recent article Fu et al reported about a 52 years old female with a mitochondrial disorder due to the variant m.10158T>C in the mtDNA located gene MT-ND3.The study has a number of shortcomings.The study would ...In a recent article Fu et al reported about a 52 years old female with a mitochondrial disorder due to the variant m.10158T>C in the mtDNA located gene MT-ND3.The study has a number of shortcomings.The study would particularly profit from providing more data about multisystem disease,from providing the current medication,the cerebro-spinal fluid findings,the detailed phenotypic presentation,and the genotype of first-degree relatives.Since the index patient had experienced recurrent seizures it is crucial to know the current and previous anti-seizure medication as it may strongly determine the outcome.Some of them are mitochondrion-toxic and particularly valproic acid may exhibit fatal side effects.The outcome may also depend on the degree of multisystem involvement why it is crucial to prospectively investigate the patient for subclinical involvement of organs not obviously affected.Additionally,the outcome of the stroke-like lesions on imaging would be interesting to see.Strokelike lesions may completely disappear or may end up as white matter lesion,laminar cortical necrosis,focal atrophy,cyst,or as the so-called toenail sign.There is also a need of discussing more profoundly the imaging findings and their diagnostic significance and to investigate first degree relatives of the index patient clinically and genetically.Though highly interesting,the presentation of this case of a mitochondrial disorder lacks clinical and genetic data of the patient and his relatives.Outcome parameters,such as severity of disease,degree of progression,drugs,pathogenicity of the mutation,and multisystem involvement require a profound discussion.展开更多
Dear Editor,With interest we read the article by Teng et al[1]about a study of the retinal nerve and ganglion cell layers by means of optic coherence tomography(OCT)in 32 patients with a mitochondrial optic neuropathy...Dear Editor,With interest we read the article by Teng et al[1]about a study of the retinal nerve and ganglion cell layers by means of optic coherence tomography(OCT)in 32 patients with a mitochondrial optic neuropathy(MON).Included were 20 patients with hereditary MON[Leber’s hereditary optic neuropathy(LHON)],12 patients with acquired MON[ethambutol-induced optic neuropathy(EION)],and 41 healthy controls.Retinal nerve fiber layer(RNFL)thickness was reduced in the nasal,superior,temporal,and inferior quadrants in LHON patients but only in the temporal quadrant in the EION patients.Thickness of the retinal ganglion cell layer(RGCL)was similarly reduced in LHON and EION patients.We have the following comments and concerns.展开更多
Mitochondrial disorders(MIDs)are usually multisystem disorders(mitochondrial multiorgan disorder syndrome)either on from onset or starting at a point during the disease course.Most frequently affected tissues are thos...Mitochondrial disorders(MIDs)are usually multisystem disorders(mitochondrial multiorgan disorder syndrome)either on from onset or starting at a point during the disease course.Most frequently affected tissues are those with a high oxygen demand such as the central nervous system,the muscle,endocrine glands,or the myocardium.Recently,it has been shown that rarely alsothe arteries may be affected(mitochondrial arteriopathy).This review focuses on the type,diagnosis,and treat-ment of mitochondrial vasculopathy in MID patients.A literature search using appropriate search terms was carried out.Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy.Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy,migraine-like headache,stroke-like episodes,or peripheral retinopathy.Mitochondrial macroangiopathy manifests as atherosclerosis,ectasia of arteries,aneurysm formation,dissection,or spontan-eous rupture of arteries.The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes.Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes.Mitochondrial vasculopathy exists and manifests as micro-or macroangiopathy.Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications.展开更多
The interesting case report by Zhang et al on a 39 years-old male with Charcot-Marie-Tooth disease type 1X has several limitations.The causal relation between the two episodes of asyndesis,dysphagia,and dyspnea 37 d a...The interesting case report by Zhang et al on a 39 years-old male with Charcot-Marie-Tooth disease type 1X has several limitations.The causal relation between the two episodes of asyndesis,dysphagia,and dyspnea 37 d after the second dose of the inactivated severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2)vaccine(Beijing Institute of Biological Products Co.,Ltd.,Beijing,China)remains unproven.SARS-CoV-2 vaccination cannot trigger a genetic disorder.It also remains unsupported that the patient had a stroke-like episode(SLE).SLEs occur in mitochondrial disorders but not in hereditary neuropathies.Because of the episodic nature of the neurological symptoms,it is critical to rule out seizures.Overall,the causal relation between vaccination and the neurological complications remains unsupported and the interpretation of symmetric diffusionweighted imaging lesions on cerebral magnetic resonance imaging should be carefully revised.展开更多
With interest we read the case report of Budnik, et al. about the oldest patient with Takotsubo cardiomyopathy （TTC） so far reported. We have the following comments and questions： TTC is frequently triggered by emo...With interest we read the case report of Budnik, et al. about the oldest patient with Takotsubo cardiomyopathy （TTC） so far reported. We have the following comments and questions： TTC is frequently triggered by emotional or physical stress. Were there any emotional or physical triggers for TTC in the presented patient？ It is indicated that the patient felt chronic stress associated with her memories of World War II. Since the World War II ended more than 70 years ago, it would be interesting if any recent event exacerbated her memories.展开更多
Dear Editor,We read with interest the article by Liu et al[1]about an optical coherence tomography(OCT)study of five patients(10 eyes)with Leber’s hereditary optic neuropathy(LHON)due to the variant m.11778 G>A in...Dear Editor,We read with interest the article by Liu et al[1]about an optical coherence tomography(OCT)study of five patients(10 eyes)with Leber’s hereditary optic neuropathy(LHON)due to the variant m.11778 G>A in MT-ND4 which were compared with 11 clinically unaffected carriers(22 eyes)of the variant and with 20 healthy controls.展开更多
It is reported that neurodegeneration is a process that is implicated in both neuropharmacological disorders and brain aging [1].Research has shown that natural products have a wide range of pharmacological and biolog...It is reported that neurodegeneration is a process that is implicated in both neuropharmacological disorders and brain aging [1].Research has shown that natural products have a wide range of pharmacological and biological activities, some of which have the potential for use in the treatment of Parkinson’s disease (PD)[1].展开更多
Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical ev...Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical evidence that NAC truly prevents coronavirus disease 2019(COVID-19),reduces the severity of the disease,or improves the outcome.Appropriately designed clinical trials are warranted to prove or disprove a therapeutic effect of NAC for COVID-19 patients.展开更多
Summary Pain is not pain because people interpret symptoms differently.Neck pain is one of the most common pains and should not be missing from a study on the effects of pain.Depression does not arise solely from pain...Summary Pain is not pain because people interpret symptoms differently.Neck pain is one of the most common pains and should not be missing from a study on the effects of pain.Depression does not arise solely from pain but is multicausal and often caused by this cumulative effect.展开更多
To the Editor,We read with interest the article by Lehrer et al.on an in silico molecular docking and molecular dynamics simulation study with Cx43 channels,which investigated whether insulin or metformin can dock wit...To the Editor,We read with interest the article by Lehrer et al.on an in silico molecular docking and molecular dynamics simulation study with Cx43 channels,which investigated whether insulin or metformin can dock within the Cx43 channel and effectively block it,thereby reducing the risk of amyotrophic lateral sclerosis(ALS)[1].Based on data from the FDA Med Watch,it was found that the insulin heterodimer docks in the center of the Cx43 channel and effectively blocks it,and that this blockade is very stable,thereby achieving a protective effect on ALS[1].It has been found that metformin also docks in the Cx43 channel,but due to the small size of the molecule,it does not impede the passage of toxic waste products from astrocytes[1].The study is impressive,but some points should be discussed.展开更多
To the Editor: With interest, we read the article by Su et al[1] about the antiepileptic drug (AED) treatment of 17 patients with genetically confirmed myoclonic epilepsy with ragged-red fibers (MERRF) syndrome. It wa...To the Editor: With interest, we read the article by Su et al[1] about the antiepileptic drug (AED) treatment of 17 patients with genetically confirmed myoclonic epilepsy with ragged-red fibers (MERRF) syndrome. It was found that monotherapy with either levetiracetam (LEV), clonazepam (CZP), valproic acid (VPA).展开更多
We appreciated reading the article by Zhang et al[1] about a retrospective study of 102 mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) patients with epilepsy in which disability and...We appreciated reading the article by Zhang et al[1] about a retrospective study of 102 mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) patients with epilepsy in which disability and outcome were assessed (median follow-up: 4 years). Administration of levetirazetam (LEV) was associated with a better outcome compared to other antiepileptic drugs (AEDs).[1] The study has several shortcomings requiring discussion.展开更多
To the Editor： With interest we read the article by Wu et all on a 53-year male with agenesia of the right lung and left-ventricular hypertrabeculation / noncompaction （LVHT）. The paper raises the following concerns.
To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors c...To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.展开更多
To the Editor： With interest, we read the article by Kwon et al. about a single patient with Kearns-Sayre syndrome （KSS）, who successfully and without complications underwent peripheral nerve block for multiple mus...To the Editor： With interest, we read the article by Kwon et al. about a single patient with Kearns-Sayre syndrome （KSS）, who successfully and without complications underwent peripheral nerve block for multiple muscle biopsies. We have the following comments and concerns.展开更多
To the Editor:Hypophosphatasia(HPP)is a musculoskeletal inborn error-of-metabolism caused by variants in alkaline phosphatase(ALPL)with reduced activity of the serum tissue-non-specific alkaline phosphatase,[1]which i...To the Editor:Hypophosphatasia(HPP)is a musculoskeletal inborn error-of-metabolism caused by variants in alkaline phosphatase(ALPL)with reduced activity of the serum tissue-non-specific alkaline phosphatase,[1]which is predominantly expressed in brain,muscle,bones,liver,and kidneys.[2]Accordingly,HPP is a multi-system disorder affecting bones and more rarely extra-osseus organs.[2]Osseus features of HPP include decreased bone quality,osteoid accumulations,reduced bone-mineralization,increased incidence of fractures,premature closure of sutures,bone deformities,dwarfism,Bechterew disease,early loss of teeth,intracranial hypertension,and prolonged bone healing.[1]Extra-osseous features of HPP include seizures,[3]myopathy,[2]hepatopathy,and renal insufficiency.HPP responds favorably to enzyme replacement therapy with asfotase-α.[1]展开更多
To the Editor:With interest,we read the article by Xu et al[1]about a 54-year old man with a multisystem mitochondrial disorder(MID)affecting the brain,ears,and muscle.Clinical manifestations were attributed to the va...To the Editor:With interest,we read the article by Xu et al[1]about a 54-year old man with a multisystem mitochondrial disorder(MID)affecting the brain,ears,and muscle.Clinical manifestations were attributed to the variant m.8363G>A in tRNA(Lys).[1]We have the following comments and concerns.展开更多
To the Editor:With interest we read the article by Fu et al[1] about a 35-year-old male patient with late-onset myoclonic epilepsy with ragged red fibers syndrome (MERRF) plus syndrome being attributed to the MT-TN va...To the Editor:With interest we read the article by Fu et al[1] about a 35-year-old male patient with late-onset myoclonic epilepsy with ragged red fibers syndrome (MERRF) plus syndrome being attributed to the MT-TN variant m.5703G>A,We have the following comments and concerns.展开更多
To the Editor： With interest, we read the article reported by Liu et al. about the frequency of central and peripheral auditory system affection in 73 patients with a mitochondrial disorder （MID） due to mitochondri...To the Editor： With interest, we read the article reported by Liu et al. about the frequency of central and peripheral auditory system affection in 73 patients with a mitochondrial disorder （MID） due to mitochondrial DNA （rntDNA） point mutations or a single mtDNA deletion. We had the following comments and concerns.展开更多
文摘Dysphagia is a common complication of ischemic stroke and is usually difficult to treat.The mainstay of standard therapy of post-stroke dysphagia(PSD)is effortful swallowing.Since its introduction in 2004,there is increasing evidence that sur-face electromyography-guided biofeedback training(EMGBT)can enhance the therapeutic effect of standard LE.In this editorial,we comment on the article by Meng et al published in the recent issue of the World Journal of Clinical Cases,which provided evidence that particularly extensive EMGBT with an increased number of sessions is definitively more effective than the standard speech therapy or or-dinary EMGBT.Among the 90 PSD patients with ischemic stroke or intracerebral bleeding,those who underwent EMGBT in more sessions than usual particularly benefited from the approach.It was concluded that EMGBT is more effective than traditional swallowing training in improving dysphagia and swallowing disor-ders as well as hyoid-laryngeal complex movement speed in PSD patients.
文摘In a recent article Fu et al reported about a 52 years old female with a mitochondrial disorder due to the variant m.10158T>C in the mtDNA located gene MT-ND3.The study has a number of shortcomings.The study would particularly profit from providing more data about multisystem disease,from providing the current medication,the cerebro-spinal fluid findings,the detailed phenotypic presentation,and the genotype of first-degree relatives.Since the index patient had experienced recurrent seizures it is crucial to know the current and previous anti-seizure medication as it may strongly determine the outcome.Some of them are mitochondrion-toxic and particularly valproic acid may exhibit fatal side effects.The outcome may also depend on the degree of multisystem involvement why it is crucial to prospectively investigate the patient for subclinical involvement of organs not obviously affected.Additionally,the outcome of the stroke-like lesions on imaging would be interesting to see.Strokelike lesions may completely disappear or may end up as white matter lesion,laminar cortical necrosis,focal atrophy,cyst,or as the so-called toenail sign.There is also a need of discussing more profoundly the imaging findings and their diagnostic significance and to investigate first degree relatives of the index patient clinically and genetically.Though highly interesting,the presentation of this case of a mitochondrial disorder lacks clinical and genetic data of the patient and his relatives.Outcome parameters,such as severity of disease,degree of progression,drugs,pathogenicity of the mutation,and multisystem involvement require a profound discussion.
文摘Dear Editor,With interest we read the article by Teng et al[1]about a study of the retinal nerve and ganglion cell layers by means of optic coherence tomography(OCT)in 32 patients with a mitochondrial optic neuropathy(MON).Included were 20 patients with hereditary MON[Leber’s hereditary optic neuropathy(LHON)],12 patients with acquired MON[ethambutol-induced optic neuropathy(EION)],and 41 healthy controls.Retinal nerve fiber layer(RNFL)thickness was reduced in the nasal,superior,temporal,and inferior quadrants in LHON patients but only in the temporal quadrant in the EION patients.Thickness of the retinal ganglion cell layer(RGCL)was similarly reduced in LHON and EION patients.We have the following comments and concerns.
文摘Mitochondrial disorders(MIDs)are usually multisystem disorders(mitochondrial multiorgan disorder syndrome)either on from onset or starting at a point during the disease course.Most frequently affected tissues are those with a high oxygen demand such as the central nervous system,the muscle,endocrine glands,or the myocardium.Recently,it has been shown that rarely alsothe arteries may be affected(mitochondrial arteriopathy).This review focuses on the type,diagnosis,and treat-ment of mitochondrial vasculopathy in MID patients.A literature search using appropriate search terms was carried out.Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy.Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy,migraine-like headache,stroke-like episodes,or peripheral retinopathy.Mitochondrial macroangiopathy manifests as atherosclerosis,ectasia of arteries,aneurysm formation,dissection,or spontan-eous rupture of arteries.The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes.Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes.Mitochondrial vasculopathy exists and manifests as micro-or macroangiopathy.Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications.
文摘The interesting case report by Zhang et al on a 39 years-old male with Charcot-Marie-Tooth disease type 1X has several limitations.The causal relation between the two episodes of asyndesis,dysphagia,and dyspnea 37 d after the second dose of the inactivated severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2)vaccine(Beijing Institute of Biological Products Co.,Ltd.,Beijing,China)remains unproven.SARS-CoV-2 vaccination cannot trigger a genetic disorder.It also remains unsupported that the patient had a stroke-like episode(SLE).SLEs occur in mitochondrial disorders but not in hereditary neuropathies.Because of the episodic nature of the neurological symptoms,it is critical to rule out seizures.Overall,the causal relation between vaccination and the neurological complications remains unsupported and the interpretation of symmetric diffusionweighted imaging lesions on cerebral magnetic resonance imaging should be carefully revised.
文摘With interest we read the case report of Budnik, et al. about the oldest patient with Takotsubo cardiomyopathy （TTC） so far reported. We have the following comments and questions： TTC is frequently triggered by emotional or physical stress. Were there any emotional or physical triggers for TTC in the presented patient？ It is indicated that the patient felt chronic stress associated with her memories of World War II. Since the World War II ended more than 70 years ago, it would be interesting if any recent event exacerbated her memories.
文摘Dear Editor,We read with interest the article by Liu et al[1]about an optical coherence tomography(OCT)study of five patients(10 eyes)with Leber’s hereditary optic neuropathy(LHON)due to the variant m.11778 G>A in MT-ND4 which were compared with 11 clinically unaffected carriers(22 eyes)of the variant and with 20 healthy controls.
基金supported by the following grants:FAPESP(Fundacao de AmparoàPesquisa do Estado de Sao Paulo)CNPq(Conselho Nacional de Desenvolvimento Científico e Tecnológico)+1 种基金CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nível Superior)FAPEMIG (Fundacao de AmparoàPesquisa do Estado de Minas Gerais)。
文摘It is reported that neurodegeneration is a process that is implicated in both neuropharmacological disorders and brain aging [1].Research has shown that natural products have a wide range of pharmacological and biological activities, some of which have the potential for use in the treatment of Parkinson’s disease (PD)[1].
文摘Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical evidence that NAC truly prevents coronavirus disease 2019(COVID-19),reduces the severity of the disease,or improves the outcome.Appropriately designed clinical trials are warranted to prove or disprove a therapeutic effect of NAC for COVID-19 patients.
文摘Summary Pain is not pain because people interpret symptoms differently.Neck pain is one of the most common pains and should not be missing from a study on the effects of pain.Depression does not arise solely from pain but is multicausal and often caused by this cumulative effect.
文摘To the Editor,We read with interest the article by Lehrer et al.on an in silico molecular docking and molecular dynamics simulation study with Cx43 channels,which investigated whether insulin or metformin can dock within the Cx43 channel and effectively block it,thereby reducing the risk of amyotrophic lateral sclerosis(ALS)[1].Based on data from the FDA Med Watch,it was found that the insulin heterodimer docks in the center of the Cx43 channel and effectively blocks it,and that this blockade is very stable,thereby achieving a protective effect on ALS[1].It has been found that metformin also docks in the Cx43 channel,but due to the small size of the molecule,it does not impede the passage of toxic waste products from astrocytes[1].The study is impressive,but some points should be discussed.
文摘To the Editor: With interest, we read the article by Su et al[1] about the antiepileptic drug (AED) treatment of 17 patients with genetically confirmed myoclonic epilepsy with ragged-red fibers (MERRF) syndrome. It was found that monotherapy with either levetiracetam (LEV), clonazepam (CZP), valproic acid (VPA).
文摘We appreciated reading the article by Zhang et al[1] about a retrospective study of 102 mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) patients with epilepsy in which disability and outcome were assessed (median follow-up: 4 years). Administration of levetirazetam (LEV) was associated with a better outcome compared to other antiepileptic drugs (AEDs).[1] The study has several shortcomings requiring discussion.
文摘To the Editor： With interest we read the article by Wu et all on a 53-year male with agenesia of the right lung and left-ventricular hypertrabeculation / noncompaction （LVHT）. The paper raises the following concerns.
文摘To the Editor: With interest we read the article by Yu et al[1] about a retrospective study of 13 pediatric patients with Leigh syndrome from a single center in China collected over a period of 17 years. The authors concluded that patients with ophthalmoplegia, muscle weakness, ataxia, and respiratory insufficiency should be screened for mutations in genes located on the mtDNA.[1] Patients with suspected Leigh syndrome are recommended to undergo determination of cerebrospinal fluid (CSF) lactate and cerebral imaging.[1] We have the following comment and concerns.
文摘To the Editor： With interest, we read the article by Kwon et al. about a single patient with Kearns-Sayre syndrome （KSS）, who successfully and without complications underwent peripheral nerve block for multiple muscle biopsies. We have the following comments and concerns.
文摘To the Editor:Hypophosphatasia(HPP)is a musculoskeletal inborn error-of-metabolism caused by variants in alkaline phosphatase(ALPL)with reduced activity of the serum tissue-non-specific alkaline phosphatase,[1]which is predominantly expressed in brain,muscle,bones,liver,and kidneys.[2]Accordingly,HPP is a multi-system disorder affecting bones and more rarely extra-osseus organs.[2]Osseus features of HPP include decreased bone quality,osteoid accumulations,reduced bone-mineralization,increased incidence of fractures,premature closure of sutures,bone deformities,dwarfism,Bechterew disease,early loss of teeth,intracranial hypertension,and prolonged bone healing.[1]Extra-osseous features of HPP include seizures,[3]myopathy,[2]hepatopathy,and renal insufficiency.HPP responds favorably to enzyme replacement therapy with asfotase-α.[1]
文摘To the Editor:With interest,we read the article by Xu et al[1]about a 54-year old man with a multisystem mitochondrial disorder(MID)affecting the brain,ears,and muscle.Clinical manifestations were attributed to the variant m.8363G>A in tRNA(Lys).[1]We have the following comments and concerns.
文摘To the Editor:With interest we read the article by Fu et al[1] about a 35-year-old male patient with late-onset myoclonic epilepsy with ragged red fibers syndrome (MERRF) plus syndrome being attributed to the MT-TN variant m.5703G>A,We have the following comments and concerns.
文摘To the Editor： With interest, we read the article reported by Liu et al. about the frequency of central and peripheral auditory system affection in 73 patients with a mitochondrial disorder （MID） due to mitochondrial DNA （rntDNA） point mutations or a single mtDNA deletion. We had the following comments and concerns.
