A Simple Procedure of Epidural Electrode Lead Replacement through a Tissue Sheath in Spinal Cord Stimulation.

Spinal cord stimulation (SCS) is widely performed to treat several types of intractable chronic pain. To maintain lasting SCS, epidural electrode leads must be replaced sometimes due to problems like lead breakage. However, in lead replacement, guiding the new lead to the original position may be difficult because granulation tissue sheath forms around the lead. We encountered a surgical case where we inserted new leads through tissue sheaths forming around the old leads from the epidural space to the thoracolumbar fascia; the lead was smoothly introduced to the original place. This procedure is simpler than previously reported techniques. Here, we report the detailed surgical procedure and review the relevant literature.

Long-term follow-up of task-specific tremor after thalamotomy: a retrospective observational study.

OBJECTIVE: This study aimed to report the long-term results of thalamotomy in 23 patients with task-specific tremor. METHODS: Data of 23 patients with task-specific tremor who underwent ventralis intermedius nucleus and posterior part of ventro-oral nucleus thalamotomy at the Tokyo Women's Medical University Hospital between 2010 and 2022 were retrospectively analyzed. To evaluate neurological conditions, the severity of task-specific tremor was divided into 0 (no tremor), 1 (slightly tremulous), 2 (moderately tremulous), 3 (accomplishing tasks with great difficulty), and 4 (unable to complete tasks). We also used the subscores "handwriting" (0-4) and "spiral drawing" (0-4) of the Clinical Rating Scales for Tremor. Evaluation scales were presented as medians and interquartile ranges. RESULTS: The severities of task-specific tremor were 3.0 (3.0-4.0) preoperatively and 0.0 (0.0-0.0, p < 0.0001) at the last available evaluation. The writing and spiral drawing of the Clinical Rating Scales for Tremor significantly improved from 3.0 (3.0-4.0) and 3.0 (2.0-3.0) preoperatively, respectively, to 0.0 (0.0-0.0, p < 0.0001) and 0.0 (0.0-0.0, p < 0.0001) at the last available evaluation, respectively. The mean clinical follow-up period was 62.7 ± 26.0 months. Seven (30.4%) patients had focal hand dystonia, which newly developed on the ipsilateral side of the tremor at 2-45 months after the surgery. No serious complications were observed. INTERPRETATION: Thalamotomy significantly improves task-specific tremor with high long-term efficacy, and long-term follow-up is important because focal hand dystonia can develop postoperatively.

Pistol Shooting Dystonia Treated with Thalamotomy.

Background: Neurosurgical treatment for pistol shooting dystonia has not been studied. Case report: The patient was a 41-year-old woman who participated in the Olympic Games four times as a shooting player. Five months after the final Tokyo Olympic trials, she developed dystonia of the right index finger when shooting. Stereotactic thalamotomy was performed, and a complete resolution of dystonia was achieved. She garnered her personal best score and placed fifth in the Tokyo Olympics. Discussion: Thalamotomy along with deep brain stimulation can be a surgical modality for patients with task-specific dystonia who fail oral medications or botulinum toxin therapy.

Jaw Claudication Caused by Atherothrombotic External Carotid Artery Occlusion: A Case Report.

Jaw claudication is a common symptom of giant cell arteritis (GCA), although atherothrombotic external carotid artery (ECA) occlusion is also known to cause jaw claudication. The patient was a 75-year-old male who experienced severe right jaw pain while chewing solid food. Magnetic resonance (MR) angiography showed right ECA occlusion. Based on laboratory tests and contrast-enhanced computed tomography (CT) angiography, atherothrombosis, not GCA, was suspected to be the cause of jaw claudication. Following conservative therapy with cilostazol, the pain was gradually alleviated in two months, and subsequent MR angiography after four months showed blood flow in the stenosed right ECA. The symptom completely disappeared in six months. Based on a previous report, we expected that jaw claudication will be ameliorated due to the development of collateral supply; however, spontaneous ECA recanalization caused improvement of symptoms in this case.

Gamma Knife Thalamotomy for Essential Tremor: A Retrospective Analysis.

BACKGROUND: Gamma knife (GK) thalamotomy has been used as a treatment option for essential tremor (ET). Numerous studies on GK use in ET treatment have reported more varied responses and complication rates. METHODS: Data from 27 patients with ET who underwent GK thalamotomy were retrospectively analyzed. The Fahn-Tolosa-Marin Clinical Rating Scale for Tremor, handwriting, and spiral drawing were evaluated. Postoperative adverse events and magnetic resonance imaging findings were also evaluated. RESULTS: The mean age at GK thalamotomy was 78.1 ± 4.2 years. The mean follow-up period was 32.5 ± 19.4 months. The preoperative postural tremor, handwriting, and spiral drawing scores were 3.4 ± 0.6, 3.3 ± 1.0, and 3.2 ± 0.8, respectively, all of which showed significant improvements to 1.5 ± 1.2 (55.9% improvement, P < 0.001), 1.4 ± 1.1 (57.6% improvement, P < 0.001), and 1.6 ± 1.3 (50% improvement, P < 0.001), respectively, at the available final follow-up evaluations. Three patients presented with no improvement in tremor. Six patients presented with adverse effects, including complete hemiparesis, foot weakness, dysarthria, dysphagia, lip numbness, and finger numbness, at the final follow-up period. Two patients presented with serious complications, including complete hemiparesis due to massive widespread edema and chronic encapsulated expanding hematoma. One patient died of aspiration pneumonia following severe dysphagia secondary to chronic encapsulated expanding hematoma. CONCLUSIONS: GK thalamotomy is an efficient procedure for treating ET. Careful treatment planning is necessary to reduce complication rates. The prediction of radiation complications will increase the safety and effectiveness of GK treatment.

Bilateral Radiofrequency Ventral Intermediate Thalamotomy for Essential Tremor.

INTRODUCTION: With the advent of MR-guided focused ultrasound, the importance of the efficacy and safety of bilateral ventral intermediate (Vim) thalamotomy for essential tremor (ET) has increased. However, reports on bilateral Vim thalamotomy for ET remain scarce. METHODS: To review the results and complications of bilateral Vim thalamotomy for the treatment of ET in the upper extremities, we retrospectively analyzed the patients with ET who underwent bilateral Vim thalamotomy with radiofrequency (RF) thermal coagulation. As bilateral simultaneous thalamotomy can cause surgical complications, thalamotomy was performed in stages. The interval between the first and second thalamotomies was 21.3 ± 14.7 months. We evaluated the efficacy using the Clinical Rating Scale for Tremor (CRST) before and after the first and second treatments, respectively. We also evaluated the complications before and after the first and second treatments, respectively. Moreover, we assessed the adverse events. RESULTS: Seventeen patients were included in the study. The mean follow-up period following the second thalamotomy was 29.3 ± 15.0 months. The CRST part A + B scores were 34.9 ± 9.7, 20.8 ± 7.0, and 7.4 ± 6.8 before, following the first (40.4% improvement, p < 0.0001) and second thalamotomies (78.6% improvement, p < 0.0001), respectively. Nine patients presented with prolonged adverse events, including dysarthria, dysgeusia, dysphagia, tongue numbness, unsteady gait, and postural instability at the last available evaluation. All adverse events were mild and did not interfere with the patient's daily activities. DISCUSSION/CONCLUSIONS: Bilateral Vim thalamotomy with RF thermal coagulation was an effective treatment for ET in both upper extremities. Despite most possible complications being mild, additional studies with a larger sample size are required to ensure patient safety.

An Experience With an Exoscope System (ORBEYE) for Surgery for Tarsal Tunnel Syndrome: A Case Report.

Surgery for peripheral entrapment neuropathy aims to decompress the affected nerve and optimize the visualization of anatomical details during surgery. This paper describes our experience using the ORBEYE exoscope (Olympus) during surgery for tarsal tunnel syndrome (TTS). The patient was a 70-year-old male with complaints of bilateral pain and numbness on the plantar surface of the bilateral soles and medial halves of both lower limbs. He was diagnosed with idiopathic TTS with the American Orthopedic Foot and Ankle Score (AOFAS) of 20/100. Surgery for the right foot was performed under local anesthesia with the patient's body in the lateral position. All procedures were performed using the ORBEYE exoscope view. The posterior tibial artery (PTA) was transposed, and the flexor retinaculum was reconstructed between the PTA and posterior tibial nerve. Indocyanine green (ICG) video angiography confirmed the absence of PTA flow disturbance. One month after the first operation, left foot surgery was performed. Three months later, the AOFAS had improved from 20/100 to 50/100. The ORBEYE exoscope is useful in TTS treatment and represents a feasible and comfortable technique for entrapment neuropathy surgery. In addition, ICG capability is an effective tool for confirming blood flow in PTA after transposition.

[Development of Medical Materials and Infection].

Surgery has the possibility to cause infections. Surgical site infection(SSI)is a common complication of various surgical procedures. On the other hand, allogeneic tissue-derived material-induced infections, such as transfusion-related hepatitis and Creutzfeldt-Jakob disease, are rare but occur. The risk of surgery-related infections needs to be reduced because such infections not only affect morbidity and mortality but also lead to increased medical costs and longer hospitalization. Recently, various allogeneic and synthetic medical materials have been developed, and many types of materials have been used in daily neurosurgical procedures. Some synthetic materials have been advertised to have an SSI-preventive effect. Technology has also been developed to minimize the infectivity of allogeneic materials. In this paper, we introduce some information focused on the infectivity of fibrin glue and DuraGen® and the SSI-preventive effect of Surgicel® and antimicrobial sutures.

Efficacy and Safety of Zolpidem for Focal Dystonia After Neurosurgical Treatments: A Retrospective Cohort Study.

Although there are several reports of the significant efficacy of zolpidem for treating dystonia, zolpidem is still considered an anecdotal treatment. Here, we evaluated the efficacy and safety of zolpidem for treating residual dystonia in patients who previously received various neurosurgical treatments majorly including deep brain stimulation and radiofrequency ablation. We retrospectively reviewed medical records from January 2021 to September 2021 to identify patients with dystonia who had been prescribed zolpidem after undergoing neurosurgery. Twenty patients were enrolled in this study, including those with blepharospasm (two), tongue dystonia (four), mouth dystonia (one), spasmodic dysphonia (two), cervical dystonia (six), focal hand dystonia (three), hemidystonia (two), blepharospasm with cervical dystonia (one), and mouth dystonia with cervical dystonia (one). Single doses of zolpidem ranged between 2.5 and 10 mg, while daily dosages ranged from 10 to 30 mg. The zolpidem dose prescribed was 5-10 mg, with single and daily doses of 7 ± 2.9 and 14.5 ± 6.0 mg, respectively. With zolpidem administration, the participants' Burke-Fahn-Marsden Dystonia Rating Scale-Movement Scale score significantly improved from 8.1 ± 6.7 to 3.7 ± 2.5 (50.6% improvement, p < 0.0001). Improvements in arm dystonia, blepharospasm, and spasmodic dysphonia were observed using the Arm Dystonia Disability Scale, Jankovic Rating Scale, and Voice Handicap Index, respectively. No improvements were observed in cervical dystonia on the Toronto Western Spasmodic Torticollis Rating Scale. Drowsiness, including three cases each of mild and moderate drowsiness, was the most frequent adverse effect (30%), which persisted for 2-3 h. Transient amnesia and rapid eye movement sleep behavior disorder occurred in two patients and one patient, respectively. Although our findings suggest that zolpidem can be a valuable treatment option for patients with residual dystonia after neurosurgical treatments, the beneficial effects for cervical dystonia were limited.

Unilateral pallidothalamic tractotomy at Forel's field H1 for cervical dystonia.

BACKGROUND: Neurosurgical ablation of Forel's field H1 for cervical dystonia, which is currently abandoned, was formerly used in the 1960s-1970s. Regardless of the lack of neuroimaging modalities and objective evaluation scales, the reported efficacy was significant. Although recent studies have reappraised the ablation of the pallidothalamic tract at Forel's field H1 for Parkinson's disease, the efficacy for cervical dystonia has not been investigated well. METHODS: Data of 35 patients with cervical dystonia who underwent unilateral pallidothalamic tractotomy at Forel's field H1 were retrospectively analyzed. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores, the neck score of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), and adverse events were evaluated preoperatively and at the last available follow-up period. RESULTS: The mean clinical follow-up period was 13.9 ± 6.5 months. The mean TWSTRS total scores were 34.3 ± 14.0 preoperatively and 18.4 ± 16.5 at the last available follow-up period (46.4% improvement, p < 0.0001). The BFMDRS neck score also improved significantly from 6.2 ± 2.9 preoperatively to 2.8 ± 2.8 at the last available follow-up period (55.0% improvement on the neck score, p < 0.0001). Reduced hand dexterity in seven patients, hypophonia in five patients, dysarthria in four patients, and executive dysfunction in one patient were confirmed as adverse events at the last available follow-up evaluation. One patient had postoperative hemorrhage. CONCLUSION: The current study confirmed significant improvement in TWSTRS total scores and BFMDRS neck scores at the 13.9-month follow-up after unilateral pallidothalamic tractotomy. The pallidothalamic tract in Forel's field H1 is expected to be an alternative treatment target for cervical dystonia.

Intraparenchymal Symptomatic Cyst Formation Around the Deep Cerebellar Stimulation Electrode.

Intraparenchymal cyst formation around a deep brain stimulation electrode is a rare complication. This is the first report of intraparenchymal cyst formation along a deep cerebellar stimulation electrode in the posterior cranial fossa. The patient was a 27-year-old man with DYT-1 early-onset isolated dystonia who received bilateral deep cerebellar stimulation. He developed dizziness, nausea, and dysarthria 1 month following the deep cerebellar stimulation surgery. Head computed tomography revealed multiple cysts along the left electrode. The contrast medium of computed tomography did not enhance the appearance of the cystic lesions. We confirmed the absence of fever and sterile cerebrospinal fluid. Steroid therapy for 3 weeks was not radiologically and symptomatically useful. He underwent aspiration surgery. The cyst fluid was light yellow, sterile, and rich in protein. Despite substantial improvement in nausea and dysarthria within 1 week postoperatively, dizziness required 1 month to recover. Cystic formations gradually decreased with time.

Deep Brain Stimulation of the Forel's Field for Dystonia: Preliminary Results.

The field of Forel (FF) is a subthalamic area through which the pallidothalamic tracts originating from the globus pallidus internus (GPi) traverse. The FF was used as a stereotactic surgical target (ablation and stimulation) to treat cervical dystonia in the 1960s and 1970s. Although recent studies have reappraised the ablation and stimulation of the pallidothalamic tract at FF for Parkinson's disease, the efficacy of deep brain stimulation of FF (FF-DBS) for dystonia has not been well investigated. To confirm the efficacy and stimulation-induced adverse effects of FF-DBS, three consecutive patients with medically refractory dystonia who underwent FF-DBS were analyzed (tongue protrusion dystonia, cranio-cervico-axial dystonia, and hemidystonia). Compared to the Burke-Fahn-Marsden Dystonia Rating Scale-Movement Scale scores before surgery (23.3 ± 12.7), improvements were observed at 1 week (8.3 ± 5.9), 3 months (5.3 ± 5.9), and 6 months (4.7 ± 4.7, p = 0.0282) after surgery. Two patients had stimulation-induced complications, including bradykinesia and postural instability, all well controlled by stimulation adjustments.

[Functional Neurosurgery for Anorexia Nervosa].

Anorexia nervosa (AN) is a serious psychiatric disorder characterized by disturbances in body- and self-perception and excessive weight loss. AN is sometimes refractory to conventional treatments such as medication and psychological therapy. Therefore, the neurosurgery for psychiatric disorders (NPD) has been studied. While the efficacy of NPD has previously been reported and is currently being studied, it is not performed in Japan. We introduce the results of representative studies that investigated functional neurosurgery for AN. (Received May 22, 2020; Accepted November 20, 2020; Published April 1, 2021).

Case Report: Deep Cerebellar Stimulation for Tremor and Dystonia.

Background: The cerebellum plays an important role in the pathogenesis and pathophysiology of movement disorders, including tremor and dystonia. To date, there have been few reports on deep cerebellar stimulation. Case Report: The patient was a 35-year-old previously healthy man with no history of movement disorders. He developed a tremor and stiffness in his left hand at the age of 27 years, which was diagnosed as a dystonic tremor. We performed right thalamotomy, which resulted in a complete resolution of the tremor; however, the dystonia persisted. Subsequently, the patient developed left foot dystonia with inversion and a newly developed tremor in the right hand and foot. The patient underwent left ventralis intermedius (VIM) deep brain stimulation (VIM-DBS) and left pallidothalamic tract DBS (PTT-DBS). Left VIM-DBS completely resolved the right hand and foot tremor, and PTT-DBS significantly improved the left hand and foot dystonia. Three months postoperatively, the patient developed an infection and wound disruption at the surgical site. We performed palliative surgery for deep cerebellar stimulation via the posterior cranial region, which was not infected. The surgery was performed under general anesthesia with the patient lying in the prone position. Eight contact DBS electrodes were used. The placement of electrodes extended from the superior cerebellar peduncle to the dentate nucleus. Both the right hand and foot tremor improved with right cerebellar stimulation. Further, both the left hand and foot dystonia improved with left cerebellar stimulation. Right and left cerebellar stimulation led to no improvement in the left hand and foot dystonia and right hand and foot tremor, respectively. Stimulation-induced complications observed in the patient included dizziness, dysphagia, and dysarthria. After the surgery, the patient developed hypersalivation and hyperhidrosis in the left side of the body, both of which did not improve with adjustments of stimulation parameters. At the 6-month follow-up, the tremor and dystonia had almost completely resolved. Conclusion: Deep cerebellar stimulation deserves consideration as a potential treatment for tremor and dystonia.

Comorbid seizure reduction after pallidothalamic tractotomy for movement disorders: Revival of Jinnai's Forel-H-tomy.

Forel-H-tomy for intractable epilepsy was introduced by Dennosuke Jinnai in the 1960s. Recently, Forel-H-tomy was renamed to "pallidothalamic tractotomy" and revived for the treatment of Parkinson's disease and dystonia. Two of our patients with movement disorders and comorbid epilepsy experienced significant seizure reduction after pallidothalamic tractotomy, demonstrating the efficacy of this method. The first was a 29-year-old woman who had temporal lobe epilepsy with focal impaired awareness seizure once every three months and an aura 10-20 times daily, even with four antiseizure medicines. For the treatment of hand dyskinesia, she underwent left pallidothalamic tractotomy and her right-hand dyskinesia significantly improved. Fourteen months later, she had experienced no focal impaired awareness seizure and the aura decreased to one to three times per month. The second case was that of a 15-year-old boy diagnosed with progressive myoclonic epilepsy, who developed generalized tonic-clonic seizure, which manifested once every month, despite treatment with five antiseizure medicines. After surgery, myoclonic movements in his right hand slightly improved. A one-year follow-up revealed that he had not experienced a generalized tonic-clonic seizure. The lesion locations in the two cases were close to the vicinity of Jinnai's Forel-H-tomy. Forel's field H deserves reconsideration as a treatment target for intractable epilepsy.

Successful Treatment of Auricular Dystonia by Unilateral Pallidothalamic Tractotomy.

Background: Ear movement disorders are rarely reported. Although some patients may respond to botulinum toxin injections, reports on surgical treatment options remain limited. Case Report: A 57-year-old woman was diagnosed with auricular dystonia, which was refractory to botulinum toxin injections. Since involuntary movement and pain were predominantly present on the right side and the patient rejected the implantation of a mechanical device, we decided to perform left pallidothalamic tractotomy. Immediately following lesioning, bilateral ear movements and right auricular pain ceased with no complications. Discussion: Stereotactic neurosurgical treatment can be an alternative for auricular dystonia. Highlights: Ear movement disorders, such as auricular myoclonus or dystonia, are rarely reported.The present case was refractory to repetitive botulinum toxin injections and oral medications.To the best of our knowledge, this is the first case of auricular dystonia that successfully improved with stereotactic neurosurgical treatment (pallidothalamic tractotomy).

Unilateral pallidotomy in the treatment of cervical dystonia: a retrospective observational study.

OBJECTIVE: The objective of this study was to assess the efficacy of unilateral pallidotomy in patients with asymmetrical cervical dystonia. METHODS: This study retrospectively included 25 consecutive patients with asymmetrical cervical dystonia refractory to botulinum toxin injections, who underwent unilateral pallidotomy between January 2015 and April 2017. Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores were evaluated preoperatively and 1 week, 3 months, and 6 months postoperatively. The clinical responses were defined as good responders, exhibiting > 50% improvement in the TWSTRS score at 6 months postsurgery, or poor responders, exhibiting < 50% improvement in TWSTRS scores at 6 months postsurgery. RESULTS: Twelve and 9 patients showed right- and left-side rotation, respectively; 1 and 3 patients had right- and left-side laterocollis, respectively. The mean age of onset and duration of the disease were 40.2 ± 13.9 and 8.9 ± 10.9 years, respectively. Mean TWSTRS scores were 38.4 ± 12.6 (p < 0.001), 17.3 ± 12.4 (p < 0.001), 19.5 ± 13.4 (p < 0.001), and 20.0 ± 14.7 (p < 0.001), preoperatively and 1 week, 3 months, and 6 months postoperatively, respectively. Fourteen patients (56%) demonstrated > 50% improvement in their TWSTRS total score (mean improvement of TWSTRS total score = 70.5%) 6 months postsurgically. Furthermore, preoperative TWSTRS severity score was a prognostic factor (odds ratio 1.37, 95% confidence interval 1.06-1.78, p = 0.003). CONCLUSIONS: These results suggest that unilateral pallidotomy is an acceptable treatment option for asymmetrical cervical dystonia. Further investigations with a larger number of cases and longer follow-up period are required to confirm these data.

Lumbar Ganglioneuroma from the Paravertebral Body Presenting in Continuity Between Intradural and Extradural Spaces.

BACKGROUND: Ganglioneuroma is a well-differentiated benign tumor that develops from the ganglion cells of the posterior mediastinum, retroperitoneum, cervical spine, and adrenal glands. The paravertebral body, in which the sympathetic trunk exists, is a common tumor site, and tumor sometimes invades the spinal canal through the intervertebral foramen. There have been no reports regarding tumors with intradural and extradural continuity. We report a paravertebral ganglioneuroma extending between the intradural and extradural spaces and its surgical treatment. CASE DESCRIPTION: A 33-year-old man was admitted to the hospital with progressive left lower limb numbness. A dumbbell-type tumor progressing to the spinal canal via the left intervertebral foramen from the paravertebral body at L1-2 was detected, and intradural calcified lesions were found. Pathologic examination of a computed tomography-guided biopsy sample revealed a ganglioglioma. The extradural tumor was removed; however, the left lower limb pain gradually worsened. As complete block was observed on myelography, the intradural tumor was removed 8 months later. Intraoperative findings revealed that the intradural and extradural tumors were continuous through the L1 nerve root. CONCLUSIONS: This is the first known reported case of paravertebral ganglioneuroma presenting in continuity between the intradural and extradural spaces.

Staged bilateral pallidotomy for dystonic camptocormia: case report.

Camptocormia is a rare, involuntary movement disorder, presenting as truncal flexion while standing or walking, and is mainly observed as a feature of Parkinson's disease (PD) and primary dystonia. Deep brain stimulation (DBS) of the globus pallidus internus is effective for refractory camptocormia observed with PD or dystonia. However, the effectiveness of pallidotomy for camptocormia has not been investigated. The authors report the case of a 38-year-old man with anterior truncal bending that developed when he was 36 years old. Prior to the onset of the symptom, he had been taking antipsychotic drugs for schizophrenia. There were no features of PD; the symptom severely interfered with his walking and daily life. He was given anticholinergics, clonazepam, and botulinum toxin injections, which did not result in much success. Because of the patient's unwillingness to undergo implantation of a hardware device, he underwent staged bilateral pallidotomy with complete resolution for a diagnosis of tardive dystonic camptocormia. The Burke-Fahn-Marsden dystonia rating scale subscore for the trunk before and after bilateral pallidotomy was 3 and 0, respectively. No perioperative adverse events were observed. Effects have persisted for 18 months. Bilateral pallidotomy can be a treatment option for medically refractory dystonic camptocormia without the need for device implantation.

Retinal artery occlusion during carotid artery stenting with distal embolic protection device.

Retinal artery occlusion associated with carotid artery stenosis is well known. Although it can also occur at the time of carotid artery stenting, retinal artery occlusion via the collateral circulation of the external carotid artery is rare. We encountered two cases of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. A 71-year-old man presented with central retinal artery occlusion after carotid artery stenting using the Carotid Guardwire PS and a 77-year-old man presented with branch retinal artery occlusion after carotid artery stenting using the FilterWire EZ. Because additional new cerebral ischaemic lesions were not detected in either case by postoperative diffusion-weighted magnetic resonance imaging, it was highly likely that the debris that caused retinal artery occlusion passed through not the internal carotid artery but collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device. It is suggested that a distal protection device for the internal carotid artery alone cannot prevent retinal artery embolisation during carotid artery stenting and protection of the external carotid artery is important to avoid retinal artery occlusion.