Immediate effects of electroacupuncture in oculomotor nerve palsy following brainstem infarction: A case report.

INTRODUCTION: Research has demonstrated that electroacupuncture (EA) stimulation of paralyzed muscles significantly improves nerve regeneration and functional recovery. DESCRIPTION: An 81-year-old man with no history of diabetes mellitus or hypertension presented with a history of brainstem infarction. Initially, the patient had medial rectus palsy in the left eye and diplopia to the right in both eyes, which almost returned to normal after six sessions of EA. METHODS: The CARE guidelines informed the case study report. The patient was diagnosed with oculomotor nerve palsy (ONP) and photographed to document ONP recovery after treatment. The selected acupuncture points and surgical methods are listed in the table. DISCUSSION: Pharmacological treatment of oculomotor palsy is not ideal, and its long-term use has side effects. Although acupuncture is a promising treatment for ONP, existing treatments involve many acupuncture points and long cycles, resulting in poor patient compliance. We chose an innovative modality, electrical stimulation of paralyzed muscles, which may be an effective and safe complementary alternative therapy for ONP.

Ischemic stroke secondary to self-inflicted carotid sinus massage: a case report.

BACKGROUND: The risk of stroke after carotid sinus massage is greater if there is preexisting carotid stenosis or carotid plaques. We present the case of a patient with underlying 40% carotid stenosis, who developed a watershed stroke after a self-neck massage in our stroke unit. We show a well-documented case with magnetic resonance images before and after the neck massage. We report a case of a watershed brain infarct after a self-massage of the carotid sinus, with preexisting carotid artery stenosis. Neck massage continues to be a significant cause of stroke and should therefore not be performed by patients. Clinicians must be aware of the implications of a carotid sinus massage in both the outpatient and inpatient settings. CASE PRESENTATION: We admitted a 58-year-old white male patient, with no relevant medical history, to our department with a brain stem infarct. During his stay at our stroke unit, the patient performed a self-neck massage with consecutive bradycardia and asystole, resulting in left-side hemiparesis. The underlying cause of the hemodynamic stroke is believed to be secondary to this intensive neck massage performed by the patient. The patient also suffered from unknown right internal carotid artery stenosis. CONCLUSION: Clinicians and patients must be aware that neck massage can lead to ischemic stroke. We postulate that repetitive impaired cardiac output can lead to a hemodynamic (watershed-type) stroke.

Stroke-Onset Seizures During Midbrain Infarction in a Patient With Top of the Basilar Syndrome.

Risk factors for early-onset seizures in acute ischemic stroke include anterior circulation stroke, infarction of the cerebral cortex, large infarct size, and ischemic-to-hemorrhagic transformation. We define stroke-onset seizures as seizures occurring within 2 hours of stroke onset. A 64-year-old woman presented with top of the basilar artery syndrome-thalamic infarction occurred first and midbrain infarction 12 days later. She manifested stroke-onset seizures during midbrain infarction, which was heralded by stupor. Within 2 hours of the onset of stupor, she had a clonic seizure of the lower extremities, electroencephalography (EEG) revealed nonconvulsive status epilepticus, and an episode of convulsive movements of all extremities was recorded on video and on EEG. Continuous EEG recording showed epileptiform discharges that would appear, disappear, and reappear over a 3-week period. It took 3 weeks and 4 antiepileptic drugs to fully suppress cortical hyperexcitability, perhaps because injury to some midbrain structures resulted in global lowering of the seizure threshold. The most important risk factor for stroke-onset seizures appears to be posterior circulation stroke, particularly brainstem infarction. The difference in risk profile between stroke-onset seizures and other forms of early-onset seizures suggest that their pathophysiology is not exactly the same. Focusing some of the research spotlight on stroke-onset seizures can help us better understand their unique clinical, electrographic, radiologic, and pathophysiologic features.

Seesaw nystagmus with internuclear ophthalmoplegia from bilateral dorsomedial pons and left thalamus infarction: a case report.

BACKGROUND: We describe for the first time the clinical features and mechanisms of a bilateral dorsomedial pons and left thalamus infarction with seesaw nystagmus and internuclear ophthalmoplegia. CASE PRESENTATION: A 62-year-old Chinese man was hospitalized for sudden-onset dizziness, diplopia, and gait disturbance. A neurological examination revealed seesaw nystagmus and internuclear ophthalmoplegia. Magnetic resonance imaging disclosed an acute infarction confined to the bilateral dorsomedial pons and left thalamus. Subsequently, 2 weeks of antithrombotic therapy led to an improvement in his symptoms. CONCLUSIONS: This case illustrates that the acute onset of seesaw nystagmus and internuclear ophthalmoplegia accompanied by risk factors for cerebrovascular diseases are highly suggestive of brainstem infarction.

[Catheter balloon dilation combined with acupuncture for cricopharyngeal achalasia after brain stem infarction: a randomized controlled trial].

OBJECTIVE: To screen the optimal acupuncture regimen for cricopharyngeal achalasia (CPA) after brain stem infarction and compare the therapeutic effect between the combined therapy of catheter balloon dilation and acupuncture and the simple application of catheter balloon dilation. METHODS: The patients suffering from neuropathic dysphagia in CPA after brain stem infarction were selected as the subjects. After confirmed in the diagnosis with video fluoroscopic swallowing study (VFSS), they were randomized into 6 groups, 15 cases in each one, named group A (routine treatment), group B (catheter balloon dilation), group C1 (treated with acupuncture in local area), group C2 (treated with acupuncture based on zangfu differentiation), group C3 (treated with acupuncture at the local area and the acupoints based on zangfu differentiation) and group D (catheter balloon dilation combined with the optimal acupuncture). Two phases were included in the study. In the first phase of study, the therapeutic effect was compared among the three acupuncture groups, named C1, C2 and C3 group, so as to screen the optimal acupuncture regimen. In the group C1, the main acupoints included Fengchi (GB 20), Wangu (GB 12), Yifeng (TE 17) and three-tongue points (Extra). In the group C2, the main acupoints were Neiguan (PC 6), Tongli (HT 5), Zusanli (ST 36) and Sanyinjiao (SP 6) as well as the supplementary acupoints in accordance with the syndrome differentiation. In the group C1 and group C2, after deqi, the electroacupuncture was used, with continuous dense wave, 5 to 8 Hz in frequency. The needles were retained for 30 min. Acupuncture was given once a day, 5 treatments a week. Before treatment, in 6 weeks of treatment or after removal of gastric tube, the rehabilitation was evaluated. In the group C3, the acupoints, manipulation and treating course were same as the group C1 and group C2. In the 2nd phase of study, theresults of rehabilitation treatment were compared among the group A, group B and group D. The treatment was given once a day, 5 times a week. Before treatment, after gastric tube removal or in 6 weeks of treatment, the evaluation was conducted. The feeding-swallowing function grade and VFSS were adopted in the evaluation among the above 6 groups. RESULTS: ① In the VFSS comparison at 1st phase of study after treatment, the food transporting ability at oral dysphagia, the results in the group C3 and group C1 were better obviously than the group C2 (both P<0.05). For the improvement in aspiration, the result in the group C3 was better obviously than the group C2 (P<0.05). In comparison of the three acupuncture groups with the group A, the difference was not significant statisticallys in the extubation rate among the four groups (P>0.05). The severity of dysphagia in the group C3 was milder than the group C2 and group A (both P<0.05). ② In the VFSS comparison at the 2nd phase of study, for the food transporting ability, the results in the group D and the group B were obviously better than the group A (both P<0.05). Regarding the function at the pharyngeal dysphagia and aspiration, the results in the group D were better than the group B and group A, those in the group B were better than the group A (all P<0.05). The difference in the extubation rate among the group A, group B and group D after treatment was significant statistically (P<0.01), of which, the extubation rate in the group D was the highest and the rate in the group A was the lowest. The dysphagia degree in the group D was milder than the group B and group A and that in the group B was milder than the group A (all P<0.05). CONCLUSION: In the study of the different acupuncture methods, the acupuncture at the local acupoints and the acupoints selected based on zangfu differentiation is the optimal acupuncture regimen for cricopharyngeal achalasia after brain stem infarction. The catheter balloon dilation combined with acupuncture present the synergistc effect on cricopharyngeal achalasia after brain stem infarction, obviously relieve dysphagia and reduce aspiration.

Effect of Transcutaneous Vagus Nerve Stimulation in Dysphagia After Lateral Medullary Infarction: A Case Report.

Purpose Severe dysphagia with weak pharyngeal peristalsis after dorsal lateral medullary infarction (LMI) requires long-term tube feeding. However, no study is currently available on therapeutic effectiveness in severe dysphagia caused by nuclear damage of vagus nerve after dorsal LMI. The purpose of the present investigation was to explore the potential of transcutaneous vagus nerve stimulation (tVNS) to improve severe dysphagia with weak pharyngeal peristalsis after dorsal LMI. Method We assessed the efficacy of 6-week tVNS in a 28-year-old woman presented with persisting severe dysphagia after dorsal LMI who had been on nasogastric feeding for 6 months. tVNS was applied for 20 min twice a day, 5 days a week, for 6 weeks. The outcome measures included saliva spitted, Swallow Function Scoring System, Functional Oral Intake Scale, Clinical Assessment of Dysphagia With Wallenberg Syndrome, Yale Pharyngeal Residue Severity Rating Scale, and upper esophagus X-ray examination. Results After tVNS, the patient was advanced to a full oral diet without head rotation or spitting. No saliva residue was found in the valleculae and pyriform sinuses. Contrast medium freely passed through the upper esophageal sphincter. Conclusion Our findings suggest that tVNS might provide a useful means for recovery of severe dysphagia with weak pharyngeal peristalsis after dorsal LMI. Supplemental Material https://doi.org/10.23641/asha.9755438.

Treatment of Medial Medullary Infarction Using a Novel iNems Training: A Case Report and Literature Review.

Objective. We describe the case of a 66-year-old Japanese male patient who developed medial medullary infarction along with severe motor paralysis and intense numbness of the left arm, pain catastrophizing, and abnormal physical sensation. We further describe his recovery using a new imagery neurofeedback-based multisensory systems (iNems) training method. Clinical Course and Intervention. The patient underwent physical therapy for the rehabilitation of motor paralysis and numbness of the paralyzed upper limbs; in addition, we implemented iNems training using EEG activity, which aims to synchronize movement intent (motor imagery) with sensory information (feedback visual information). Results. Considerable improvement in motor function, pain catastrophizing, representation of the body in the brain, and abnormal physical sensations was accomplished with iNems training. Furthermore, iNems training improved the neural activity of the default mode network at rest and the sensorimotor region when the movement was intended. Conclusions. The newly developed iNems could prove a novel, useful tool for neurorehabilitation considering that both behavioral and neurophysiological changes were observed in our case.

Adolphe Gubler (1821-1879) or Parisian neurology outside La Salpêtrière in the age of Jean-Martin Charcot.

Adolphe Gubler (1821-1879) is a typical example of a 19th century hospital physician in Paris. Head of a medical unit at Beaujon hospital in 1855, he was nominated to the treatment and pharmacognosia Chair in 1868. He trained many students who became his disciples and remained very close to him. Gubler published prolifically in all areas of medicine. His most well-known work is clearly his contribution to the study of vascular accidents affecting the brain stem, which Auguste Millard worked on simultaneously; hence the eponymous Millard-Gubler syndrome, an example of crossed hemiplegia. Following a brief biography, we will present Gubler's main publications in the area of neurology: on migraine, neurological damage during acute rheumatic fever, aphasia, and the autonomic nervous system. Much of this work was carried out through student theses that Gubler directed. The fame of his contemporary Jean-Martin Charcot (1825-1893) eclipsed that of Gubler, even though the latter was well known and respected among Parisian professors. By tying together the diverse threads of his work, we hope to renew interest in this 19th century neurologist.

Catheter balloon dilation combined with acupuncture for cricopharyngeal achalasia after brain stem infarction: a randomized controlled trial / 中国针灸

OBJECTIVE@#To screen the optimal acupuncture regimen for cricopharyngeal achalasia (CPA) after brain stem infarction and compare the therapeutic effect between the combined therapy of catheter balloon dilation and acupuncture and the simple application of catheter balloon dilation.@*METHODS@#The patients suffering from neuropathic dysphagia in CPA after brain stem infarction were selected as the subjects. After confirmed in the diagnosis with video fluoroscopic swallowing study (VFSS), they were randomized into 6 groups, 15 cases in each one, named group A (routine treatment), group B (catheter balloon dilation), group C1 (treated with acupuncture in local area), group C2 (treated with acupuncture based on differentiation), group C3 (treated with acupuncture at the local area and the acupoints based on differentiation) and group D (catheter balloon dilation combined with the optimal acupuncture). Two phases were included in the study. In the first phase of study, the therapeutic effect was compared among the three acupuncture groups, named C1, C2 and C3 group, so as to screen the optimal acupuncture regimen. In the group C1, the main acupoints included Fengchi (GB 20), Wangu (GB 12), Yifeng (TE 17) and three-tongue points (Extra). In the group C2, the main acupoints were Neiguan (PC 6), Tongli (HT 5), Zusanli (ST 36) and Sanyinjiao (SP 6) as well as the supplementary acupoints in accordance with the syndrome differentiation. In the group C1 and group C2, after , the electroacupuncture was used, with continuous dense wave, 5 to 8 Hz in frequency. The needles were retained for 30 min. Acupuncture was given once a day, 5 treatments a week. Before treatment, in 6 weeks of treatment or after removal of gastric tube, the rehabilitation was evaluated. In the group C3, the acupoints, manipulation and treating course were same as the group C1 and group C2. In the 2nd phase of study, theresults of rehabilitation treatment were compared among the group A, group B and group D. The treatment was given once a day, 5 times a week. Before treatment, after gastric tube removal or in 6 weeks of treatment, the evaluation was conducted. The feedingswallowing function grade and VFSS were adopted in the evaluation among the above 6 groups.@*RESULTS@#① In the VFSS comparison at 1st phase of study after treatment, the food transporting ability at oral dysphagia, the results in the group C3 and group C1 were better obviously than the group C2 (both 0.05). The severity of dysphagia in the group C3 was milder than the group C2 and group A (both <0.05). ② In the VFSS comparison at the 2nd phase of study, for the food transporting ability, the results in the group D and the group B were obviously better than the group A (both <0.05). Regarding the function at the pharyngeal dysphagia and aspiration, the results in the group D were better than the group B and group A, those in the group B were better than the group A (all <0.05). The difference in the extubation rate among the group A, group B and group D after treatment was significant statistically (<0.01), of which, the extubation rate in the group D was the highest and the rate in the group A was the lowest. The dysphagia degree in the group D was milder than the group B and group A and that in the group B was milder than the group A (all <0.05).@*CONCLUSION@#In the study of the different acupuncture methods, the acupuncture at the local acupoints and the acupoints selected based on differentiation is the optimal acupuncture regimen for cricopharyngeal achalasia after brain stem infarction. The catheter balloon dilation combined with acupuncture present the synergistc effect on cricopharyngeal achalasia after brain stem infarction, obviously relieve dysphagia and reduce aspiration.

Top of the Basilar Syndrome after 2nd Cervical Spine Fracture

Top of the basilar (TOB) syndrome occurs with occlusion of the rostral portion of the basilar artery that supplies blood to the midbrain, thalamus, and temporal and occipital lobes. Symptoms associated with TOB include decreased alertness, abnormal eye movement, dysarthria, and disorders of cerebellar function. A 47-year-old man was transferred to our hospital to manage C2 vertebral fracture sustained in a traffic accident. He was alert on arrival; however, he lapsed into semicoma. He was diagnosed with TOB. Thrombolytic agents could not be administered due to a contraindication in cervical spine fracture. Brain magnetic resonance imaging showed acute infarction of the pons, cerebellum, and posterior cerebral artery territory. This rare case demonstrates that C2 vertebral fracture can result in TOB.

Teaching mindfulness meditation to adults with severe speech and physical impairments: An exploratory study.

People with severe speech and physical impairments may benefit from mindfulness meditation training because it has the potential to enhance their ability to cope with anxiety, depression and pain and improve their attentional capacity to use brain-computer interface systems. Seven adults with severe speech and physical impairments (SSPI) - defined as speech that is understood less than 25% of the time and/or severely reduced hand function for writing/typing - participated in this exploratory, uncontrolled intervention study. The objectives were to describe the development and implementation of a six-week mindfulness meditation intervention and to identify feasible outcome measures in this population. The weekly intervention was delivered by an instructor in the participant's home, and participants were encouraged to practise daily using audio recordings. The objective adherence to home practice was 10.2 minutes per day. Exploratory outcome measures were an n-back working memory task, the Attention Process Training-II Attention Questionnaire, the Pittsburgh Sleep Quality Index, the Perceived Stress Scale, the Positive and Negative Affect Schedule, and a qualitative feedback survey. There were no statistically significant pre-post results in this small sample, yet administration of the measures proved feasible, and qualitative reports were overall positive. Obstacles to teaching mindfulness meditation to persons with SSPI are reported, and solutions are proposed.

[Clinical observation on medulla oblongata palsy after brainstem infarction treated with electroacupuncture at eight-neck-occiput points].

OBJECTIVE: To compare the differences in the efficacy on speech and swallowing dysfunction of medulla oblongata palsy (MOP) after brainstem infarction between electroacupuncture at eight-neck-occiput points and routine acupoints. METHODS: Seventy-two patients were randomized into a neck-occiput points group and a meridian points group, 36 cases in each one. In the neck-occiput points group, the eight-neck-occiput points (Neck 1-4 points, Occiput 1-4 points) were selected. In the meridian points group, Lianquan (CV 23), Futu (LI 18), Tongli (HT 5), Hegu (LI 4) and the others were selected. Electroacupuncture was used in the two groups, dense-dispersion wave, retaining for 30 min. The treatment was given once a day, 5 treatments a week. Totally, 4 weeks were required. The symptom scores of speech and swallowing dysfunction were observed before and after treatment in the two groups. The efficacy was compared between the two groups. RESULTS: The scores of speech and swallowing dysfunction were improved significantly after treatment in the two groups (P < 0.05, P < 0.01). The results in the neck-occiput points group were better than those in the meridian points group (both P < 0.01). The curative rate of speech dysfunction was 30.6% (11/36) and that of swallowing dysfunction was 22.2% (8/ 36) in the neck-occiput points group, which were better than 11.1% (4/36) and 5.6% (2/36) in the meridian points group, respectively. The differences were significant in comparison of the two groups (P < 0.01, P < 0.05). CONCLUSION: Electroacupuncture at eight-neck-occiput points achieves a better efficacy on speech and swallowing dysfunction of MOP after brainstem infarction as compared with the routine acupoints. This therapy is characterized as more accurate point localization and safer operation.

Clinical observation on medulla oblongata palsy after brainstem infarction treated with electroacupuncture at eight-neck-occiput points / 中国针灸

<p><b>OBJECTIVE</b>To compare the differences in the efficacy on speech and swallowing dysfunction of medulla oblongata palsy (MOP) after brainstem infarction between electroacupuncture at eight-neck-occiput points and routine acupoints.</p><p><b>METHODS</b>Seventy-two patients were randomized into a neck-occiput points group and a meridian points group, 36 cases in each one. In the neck-occiput points group, the eight-neck-occiput points (Neck 1-4 points, Occiput 1-4 points) were selected. In the meridian points group, Lianquan (CV 23), Futu (LI 18), Tongli (HT 5), Hegu (LI 4) and the others were selected. Electroacupuncture was used in the two groups, dense-dispersion wave, retaining for 30 min. The treatment was given once a day, 5 treatments a week. Totally, 4 weeks were required. The symptom scores of speech and swallowing dysfunction were observed before and after treatment in the two groups. The efficacy was compared between the two groups.</p><p><b>RESULTS</b>The scores of speech and swallowing dysfunction were improved significantly after treatment in the two groups (P < 0.05, P < 0.01). The results in the neck-occiput points group were better than those in the meridian points group (both P < 0.01). The curative rate of speech dysfunction was 30.6% (11/36) and that of swallowing dysfunction was 22.2% (8/ 36) in the neck-occiput points group, which were better than 11.1% (4/36) and 5.6% (2/36) in the meridian points group, respectively. The differences were significant in comparison of the two groups (P < 0.01, P < 0.05).</p><p><b>CONCLUSION</b>Electroacupuncture at eight-neck-occiput points achieves a better efficacy on speech and swallowing dysfunction of MOP after brainstem infarction as compared with the routine acupoints. This therapy is characterized as more accurate point localization and safer operation.</p>

Occlusion of the artery of Percheron: an unusual cause of bilateral stroke.

The artery of Percheron is a rare anatomical variant whereby a single vessel arising from the proximal segment of one posterior cerebral artery supplies both medial thalami. This is a rare example of a single arterial supply to brain structures on both sides of the midline. Occlusion of the artery of Percheron results in bilateral medial thalamic infarction, which is manifest clinically as gaze paresis, cognitive disturbance and altered consciousness. The presentation can mimic subarachnoid haemorrhage, drug intoxication, encephalitis and other inflammatory or infective conditions. The presentation is similar to the 'top of the basilar syndrome' and early recognition should prompt further investigation for underlying stroke aetiologies and consideration can be given to thrombolysis if vascular occlusion can be confirmed.

Vertical one-and-a-half syndrome with contralesional pseudo-abducens palsy in a patient with thalamomesencephalic stroke.

We report a unique neuroophthalmological syndrome consisting of vertical one-and-a-half syndrome-resulting from a combination of supranuclear conjugate upgaze palsy associated with left infranuclear (fascicular) third nerve involvement (Weber syndrome)-with concomitant contralesional pseudo-abducens palsy. Magnetic resonance imaging confirmed that this unusual clinical combination was the result of two infarcts one in the left thalamomesencephalic junction and another affecting the left infrategmental paramedian area of the rostral midbrain. We discuss the clinical topography of both neuroophthalmological findings. This unusual neuroophthalmological finding has not been reported.

Stuttering after right cerebellar infarction: a case study.

UNLABELLED: We report a male patient with neurogenic stuttering after cerebellar infarction. He had suffered from frontal and thalamus damage and he had exhibited aphasia, but his speech had been fluent until onset of the cerebellar infarction. Results of analysis of speech samples included the following: (1) the patient showed very frequent syllable repetition and part-word repetition. (2) The stuttering occurrence rate at the second test was much higher than at the first test. (3) Almost all stuttering occurred on initial word sounds; stuttering on the medial and final word was less frequent. (4) Adaptation effect was absent. (5) Secondary behaviors such as closing of the eyes and grimacing were observed. The internal model related to cerebellar functions can be modified using feedback-error information. Results suggest that internal model dysfunction caused this patient's stuttering. EDUCATIONAL OBJECTIVES: After reading this text, the reader will be able to: (1) provide characteristics of neurogenic stuttering after the cerebellum infarction; (2) discuss the relationship between neurogenic stuttering and functions of the cerebellum.

Phrenic nerve stimulation: the Australian experience.

Phrenic nerve stimulation is a technique whereby a nerve stimulator provides electrical stimulation of the phrenic nerve to cause diaphragmatic contraction. The most common indications for this procedure are central alveolar hypoventilation and high quadriplegia. This paper reviews the available data on the 19 patients treated with phrenic nerve stimulation in Australia to date. Of the 19 patients, 14 required pacing due to quadriplegia, one had congenital central hypoventilation syndrome and one had brainstem encephalitis. Information was unavailable for the remaining three patients. Currently, 11 of the pacers are known to be actively implanted, with the total pacing duration ranging from 1 to 21 years (mean 13 years). Eight of the 19 patients had revision surgeries. Four of these were to replace the original I-107 system (which had a 3-5-year life expectancy) with the current I-110 system, which is expected to perform electrically for the patient's lifetime. Three patients had revisions due to mechanical failure. The remaining patients' notes were incomplete. These data suggest that phrenic nerve stimulation can be used instead of mechanical ventilators for long-term ongoing respiratory support.

Weber's syndrome with vertical gaze palsy.

Weber's syndrome with vertical gaze palsy is rarely reported in literature. We present a case of a 47-year-old female who developed sudden onset of left exotropia, right sided hemiplegia and vertical gaze palsy. Magnetic resonance imaging (MRI) showed multiple infarcts involving both thalami and extending caudally into the midbrain. This case presents the diverse clinical picture following midbrain infarcts.

Impairment of perinatal hypoxia-ischemia to the preterm brainstem.

Hypoxia-ischemia is a major perinatal problem that results in severe damage to the newborn brain. This study assessed functional integrity of the brainstem at term in preterm infants after perinatal hypoxia-ischemia to shed light on the influence of hypoxia-ischemia on the preterm brainstem. We recruited sixty-eight preterm infants after perinatal hypoxia-ischemia, ranging in gestation 28-35 weeks. Brainstem evoked response was studied at term age (37-42 weeks postconceptional age) with 91-910/s clicks using the maximum length sequence technique. Compared with healthy preterm infants, the preterm infants after perinatal hypoxia-ischemia showed a significant increase in I-V interval at very high rates 455 and 910/s of clicks (P<0.05, 0.05). III-V interval and III-V/I-III interval ratio also increased significantly at 455 and 910/s (P<0.05-0.01). The slope of III-V interval-rate function was significantly steeper than in the healthy preterm infants (P<0.05). Compared with normal term controls, the preterm infants after hypoxia-ischemia showed similar, but slightly more significant, abnormalities. The differences between the preterm infants after hypoxia-ischemia and the healthy preterm and term infants generally increased with increasing click rate. These results demonstrated that central components of brainstem auditory evoked response were abnormal at very high click rates in the preterm infants after perinatal hypoxia-ischemia. Click rate-dependent change in the more central part of the brainstem is also abnormal. Apparently, functional integrity of the brainstem, mainly in the more central part, is impaired. Hypoxic-ischemic damage to the preterm brainstem is unlikely to completely recover within a relatively short period after the insult, which is of clinical importance.