Spinal magnetic resonance imaging artifacts in lumboperitoneal shunt surgery using adjustable valve implantation on the paravertebral spinal muscles.

BACKGROUND: Adjustable shunt valves that have been developed for managing hydrocephalus rely on intrinsically magnetic components ; thus, artifacts with these valves on magnetic resonance imaging (MRI) are inevitable. No studies on valve-induced artifacts in lumboperitoneal shunt (LPS) surgery have been published. Therefore, this study aimed to evaluate valve-induced artifacts in LPS. METHODS: We retrospectively reviewed all MRIs obtained between January 2023 and June 2023 in patients with an implanted Codman CERTAS Plus adjustable shunt valve (Integra Life Sciences, Princeton, New Jersey, USA). The valve was placed <1 cm subcutaneously on the paravertebral spinal muscle of the back, with its long axis perpendicular to the body axis. The scans were performed using a Toshiba Medical Systems 1.5 Tesla scanner. The in-plane artifact sizes were assessed as the maximum distance of the artifact from the expected region of the back. RESULTS: All spinal structures or spinal cords can be recognized, even with valve-induced artifacts. The median maximum valve-induced artifact distance on T1-weighted axial imaging was 25.63 mm (mean, 25.98 mm ; range, 22.24-30.94 mm). The median maximum valve-induced artifact distance on T2-weighted axial imaging was 25.56 mm (mean, 26.27 mm ; range, 21.83-29.53 mm). CONCLUSION: LPS surgery with adjustable valve implantation on paravertebral muscles did not cause valve-induced artifacts in the spine and spinal cord. We considered that LPS could simplify the postoperative care of these patients. J. Med. Invest. 71 : 154-157, February, 2024.

Rare complication of lumboperitoneal shunt with distal catheter migration into the inguinal hernia sac in two adults: A case report.

Background: Despite the proven benefits of lumboperitoneal shunt (LPS) for idiopathic normal-pressure hydrocephalus, complications such as catheter migration remain a problem. Inguinal complications of the distal catheter are rare in adults, and their management is uncertain. Herein, we present two cases of distal catheter migration into the inguinal hernia sac after LPS in adults and recommend their management. Case Description: An 86-year-old man presented with inguinal swelling. In another 82-year-old man who did not show any improvement after LPS, shunt angiography revealed LPS dysfunction due to lumbar catheter occlusion and distal LPS catheter in the right inguinal hernia sac, and lumbar catheter reconstruction was performed. Both patients did not have any symptoms, except inguinal swelling, and were followed up. After 2 weeks and 4 days, the distal catheter moved into the peritoneal cavity. Conclusion: Inguinal complications due to the migration of the distal catheter into the inguinal hernia sac are rare in LPS because frequent movements of the distal catheter due to trunk rotation dislodge it from the inguinal hernia sac for a short period. Urgent surgery was not recommended because the catheter was moved in a short period and the patients did not wish to undergo hernia repair.

A Case of Suspected Radiation-Induced Meningioma That Developed 36 Years after Radiotherapy for a Suprasellar Tumor.

Recently, the improvements in the prognosis of childhood brain tumors have made it necessary to consider the risk of radiation-induced brain tumor development in long-term survivors. In this report, we describe a case of radiation-induced meningioma (RIM) treated surgically 36 years after radiotherapy. A 46-year-old woman, who underwent craniotomy for suprasellar germ cell tumor at 10 years of age with additional postoperative radiotherapy, was admitted to the emergency room with consciousness disturbance and right hemiplegia. One year earlier, magnetic resonance imaging (MRI) revealed a 1-cm diameter tumor in the left middle cranial fossa. This MRI showed an enlarged brain tumor in same lesion with clearly enhanced by gadolinium. A RIM located on a left sphenoid ridge with a fast growth rate was diagnosed, and the gross total removal was achieved by a left frontotemporal craniotomy. Histological diagnosis of atypical meningioma (World Health Organization grade II) was made. RIMs are frequently atypical, anaplastic meningiomas that have already been treated with radiotherapy, making additional postoperative radiotherapy difficult; the removal rate must be increased to achieve a good prognosis. In the case of long-term survivors after childhood radiotherapy, a strict follow-up with the occurrence of RIM in mind is necessary.

Small vestibular schwannoma presented with trigeminal neuralgia: illustrative case.

BACKGROUND: A vestibular schwannoma (VS) presenting with paroxysmal facial electric shock pain, that is, trigeminal neuralgia (TN), is relatively rare. Furthermore, TN is extremely rare in small VSs. OBSERVATIONS: Herein, the authors report the case of a 52-year-old woman with a complaint of right TN. Magnetic resonance (MR) imaging revealed a right VS of 12-mm diameter that compressed the trigeminal nerve. Although she did not report any hearing impairment, audiometry revealed decreased high-frequency range on the right side. The tumor was excised using the right retrosigmoid approach, and TN was confirmed to be caused by direct compression of the trigeminal nerve by the VS. Sufficient decompression of trigeminal nerve was done. The proximity of the trigeminal nerve root to the vestibular nerve root was the cause of TN. TN disappeared immediately after surgery, and there was no worsening of hearing impairment and facial paralysis. LESSONS: It is important to remember that TN may occur with direct tumor compression, even in small VSs. A preoperative 3-dimensional MR cisternogram/angiogram fusion image clearly showed direct tumor compression of the trigeminal nerve and the absence of responsible vessels, which was useful for surgical planning.

Unruptured aneurysm at bifurcation of super short middle cerebral artery mimicking duplicated middle cerebral artery aneurysm.

Background: Duplicated middle cerebral artery (DMCA) is a normal variation of the middle cerebral artery (MCA), and distinguishing DMCA from other arteries based only on the angiographical findings is sometimes difficult. Case Description: Preoperative angiography of a 60-year-old woman revealed two MCAs originating near the top of the right internal carotid artery and a 6-mm-sized aneurysm located between these two MCAs. The ipsilateral A1 segment of the anterior cerebral artery was not visualized due to hypoplasia. The patient was diagnosed with an unruptured aneurysm at the bifurcation between MCA and DMCA, preoperatively. However, during clipping surgery, the hypoplastic A1 segment was observed at approximately 2 mm proximal to the bifurcation of the MCA, indicating that these two MCAs were not "true" MCA and DMCA, but rather two normal MCA trunks bifurcated from the very short prebifurcation segment of M1. This difference in interpretation was due to the fact that the hypoplastic A1 was not visualized on preoperative examinations. The patient was discharged following the surgery without any neurological deficits. Conclusion: The distinction between DMCA and MCA trunks from the very short prebifurcation segment of MCA might be difficult, especially when the ipsilateral A1 segment is hypoplastic. Such an M1 with a length of 2-3 mm might be named super short M1. Thus, it is necessary to confirm the anatomy during aneurysm surgery.

In vivo goat brain model for neurosurgical training.

Background: Novice neurosurgeons require neurosurgical technique training, but the current method is demanding and time consuming. Therefore, it is crucial to perform training using an appropriate and informative method. In this report, we describe our attempts to provide training in neurosurgical techniques using goat in vivo brain model and to demonstrate the effectiveness of this model. Methods: Under general anesthesia, the surgery was performed on a male goat in the prone position. A midline liner skin incision was made in the scalp, six burr holes were drilled, a craniectomy was performed, and the dura was incised in an arcuate fashion. We attempted the interhemispheric approach and a retrosigmoid approach. Results: It was confirmed that common neurosurgical approaches are achievable in this model. Furthermore, anatomical structures such as nerves and blood vessels were similar to those of humans. Moreover, the goat brain was similar in color and texture to that of humans. Conclusion: Unlike a cadaver brain, in vivo brain requires hemostasis and careful dissection, which provides the surgeons a realistic experience of actual neurosurgery.

Intermediate nerve neuralgia developed during hemifacial spasm follow-up: illustrative case.

BACKGROUND: Intermediate nerve neuralgia (INN) is a rare condition believed to be caused by vascular compression, with external auditory canal pain as the chief symptom. The authors reported a rare case of a 78-year-old woman who developed INN during follow-up for hemifacial spasm (HFS). OBSERVATIONS: The patient had been receiving Botox treatment for right HFS for 20 years when she developed paroxysmal electric shock pain in the right external auditory canal and tinnitus induced by opening her mouth. A three-dimensional magnetic resonance fusion image showed the cisternal portion of the facial-vestibulocochlear nerve complex to be compressed by the meatal loop of the anterior inferior cerebellar artery (AICA), which was pressed against by the posterior inferior cerebellar artery. The authors diagnosed INN, and microvascular decompression (MVD) was performed. Surgical findings were consistent with preoperative neuroimaging. In addition, the proximal portion of the meatal loop of the AICA had passed between the facial and vestibulocochlear nerves, compressing both. The AICA was moved and the nerve completely decompressed. All symptoms improved immediately following surgery. LESSONS: When INN occurs during HFS follow-up, aggressive MVD should be considered based on detailed neuroimaging. This treatment is a very effective single-stage cure for INN, HFS, and vestibulocochlear symptoms.

Retrograde endovascular revascularization for chronic total occlusion of the internal carotid artery: a case report.

Endovascular revascularization of a chronically occluded internal carotid artery (ICA) is challenging because the occlusive segment can be long and tortuous. A case is presented of a successful recanalization of a chronically occluded ICA by retrograde passing of a guidewire from the intracranial ICA to the cervical ICA via the posterior communicating artery. This case suggests that a retrograde approach for reopening an occluded artery may be useful during neurovascular interventions, similar to percutaneous coronary interventions. In this patient, daily transient ischemic attacks disappeared after successful recanalization of the ICA.

A complete thrombotic large aneurysm at the nonbranching segment of the distal anterior cerebral artery mimicking a cavernous malformation: illustrative case.

BACKGROUND: Thrombotic aneurysms at the nonbranching segment of the distal anterior cerebral artery (ACA) are extremely rare and difficult to differentiate from cavernous malformations by radiographic features alone. OBSERVATIONS: Computed tomography and magnetic resonance imaging of a 30-year-old female patient with a chronic headache complaint revealed a 22-mm frontal lobe mass. The mass showed heterogeneous mixed intensity and hemosiderin deposits on magnetic resonance images. It was not visualized by conventional angiography, indicating that the mass and ACA/other vessels were not connected. The patient was preoperatively diagnosed with a cavernous malformation. However, during resection, the mass surface was white and smooth, different from a cavernous malformation. Although the mass was adherent to the pericallosal artery branch, no luminal continuity was observed. After detachment, the mass was completely resected. Pathological and immunohistochemical findings indicated a vessel wall and interior thrombus. The patient was rediagnosed with a thrombotic aneurysm at the distal ACA nonbranching segment and discharged 10 days postsurgery without neurological deficits. LESSONS: Because radiographic findings of thrombotic aneurysm and cavernous malformation are similar, mass lesions in contact with major arteries should be differentiated as thrombotic aneurysms, even when the artery lumen appears disconnected from the mass.

A Case of Intravascular Treatment for Acute Ischemic Stroke with Internal Carotid Artery Stenosis That Developed While Driving.

Objective: We report a case of acute cerebral infarction that may have been associated with high-energy trauma due to onset while driving. Case Presentation: A 67-year-old man had a traffic accident. His neurological symptoms were left hemiplegia and contrast CT revealed right middle cerebral artery occlusion. Intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) and intravascular treatment were performed. Right carotid artery angiography demonstrated internal carotid artery stenosis. Middle cerebral artery (MCA) revascularization was performed only by percutaneous transluminal angioplasty (PTA) of the internal carotid artery. Thoracic hemorrhage was observed a few hours after surgery, and hemostasis was performed by thoracotomy. Carotid artery stenting (CAS) was performed 8 days after onset. The patient was transferred to a convalescent rehabilitation hospital. Conclusion: Rt-PA and acute CAS were not recommended for cerebral infarction due to traffic accident.

Optimal first coil selection to avoid aneurysmal recanalization in endovascular intracranial aneurysmal coiling.

BACKGROUND: Aneurysmal recanalization is a problem with endovascular coiling and one of its risk factors is the low volume embolization ratio (VER). The first coil VER (1st VER) is believed to be critical for obtaining a high VER. The main objective of this study was to evaluate factors potentially useful for selecting the optimal 1st VER for endovascular coiling. METHODS: 609 initial saccular aneurysmal treatments performed between January 2010 and December 2014 at our institution were included in this retrospective study. Attempted procedures, retreatment cases, intraoperative rupture cases, and stent-assisted coiling cases were excluded. Age, sex, aneurysm location, ruptured aneurysm, aneurysm shape, neck size, maximum aneurysm size, dome-to-neck ratio, aneurysm volume, procedure, immediate Raymond scale score, 1st VER, and VER between the recanalization groups and non-recanalization groups were compared. RESULTS: The factors related to recanalization were ruptured aneurysms, neck width, maximum aneurysm size, aneurysm volume, procedure, 1st VER, and VER. The cut-off values for aneurysm recanalization were a 1st VER of 10.0% and a VER of 33.0%. The maximum average VER of normal size aneurysms was found in the groups with a 1st VER of 17.5-20.0%. CONCLUSIONS: 1st VER was found to be a helpful index for estimating aneurysmal recanalization after coil embolization. The target 1st VER was 17.5-20.0% for obtaining a higher VER and avoiding recanalization.

[Usefulness of Bilateral rSO2 Monitoring for Predicting Cerebral Hyperperfusion Syndrome after Carotid Artery Stenting].

OBJECTIVE: Cerebral hyperperfusion syndrome(CHS)and cerebral hyperperfusion phenomenon(CHP)induce intracranial hemorrhage and can become critical complications after carotid artery stenting(CAS). The purpose of the present study was to predict and avoid CHS after CAS using bilateral rSO2 intraoperative monitoring. METHODS: We retrospectively analyzed 100 consecutive patients who underwent CAS between January 2012 and May 2014 in our institution. We performed continuous bilateral rSO2 monitoring from anesthetic induction to the day following CAS. CHS was defined as the deterioration of neurological conditions post-CAS, no ischemic changes on post-CAS head CT or brain MRI, an increase in cerebral blood flow(CBF)and cerebral blood volume(CBV), and shortening of the mean transit time(MTT)or time to peak(TTP)on CT perfusion. To compare the CHS/CHP group and non-CHS/CHP group, we defined four parameters:rSO2 difference(rSO2 at the endpoint of the procedure-baseline rSO2), ΔrSO2 difference(affected side rSO2 difference-unaffected side rSO2 difference), rSO2 ratio(rSO2 at the endpoint of the procedure/baseline rSO2), and ΔrSO2 ratio(affected side rSO2 ratio/unaffected side rSO2 ratio). RESULTS: There were 2 CHS cases(2.2%)and 3 CHP cases(3.3%). In the CHS/CHP group, the ΔrSO2 difference and ΔrSO2 ratio were significantly higher than those in the non-CHS/CHP group(p value<0.05);however, no significant differences were found in the affected side rSO2 difference(p value=0.063)and affected side rSO2 ratio(p value=0.054)between the groups. CONCLUSION: We could promptly detect CHS and CHP in all cases by using continuous bilateral rSO2 monitoring and analysis of the ΔrSO2 difference and ΔrSO2 ratio.

The safety and efficacy of preoperative embolization of meningioma with N-butyl cyanoacrylate.

OBJECTIVE: Preoperative embolization of meningioma is commonly performed; however, there is no consensus on the best embolic material to reduce intraoperative blood loss and surgery time. METHOD: We retrospectively assessed the safety and efficacy of 56 cases of preoperative embolization of the middle meningeal artery with N-butyl cyanoacrylate (NBCA) in 105 cases of surgery for meningioma. We also defined a blood loss to tumor volume ratio to compensate for bias caused by tumor volume, and analyzed limited cases (the embolized group n = 52, the non-embolized group n = 21) of the convexity, the parasagittal region, the falx, and the sphenoidal ridge. RESULT: The blood loss to tumor volume ratio was significantly less in the embolized group (p < 0.007). Preoperative embolization could be useful for cases with the external carotid artery as the dominant feeder vessel (p < 0.02); however, the efficacy decreased for cases with an internal carotid artery feeder. Transient complications occurred in four cases (hemiparesis secondary to edema: two cases; intratumoral bleeding: one case; trigeminal nerve disorder: one case). The cases that showed a postoperative increase in edema or intratumoral bleeding were large tumors with the early filling of veins. For such cases, surgeons should pay close attention to slow injection speed and higher NBCA viscosity, not to cause the occlusion of draining vessels. CONCLUSION: Tumor embolization with NBCA can be safely performed, and the procedure significantly reduces intraoperative blood loss.

[Cognitive dysfunction in patients with pontine hemorrhage].

PURPOSE: Cognitive dysfunctions with stroke of the brain stem are rare. We focused on and examined cognitive dysfunction after pontine hemorrhages. OBJECT AND METHOD: After July 2008, we treated 23 patients with pontine hemorrhages. Only 10 patients were included, all other patients had old hemorrhages, venous anomalies, and disturbances of consciousness. The patients included six men and four women, aged 51 years to 86 years old. The volume of hematoma was 0.11-5.20mL(average:1.74mL);there were six right side, two left side, two bilateral, three ventral, and seven dorsal hematomas. We performed neuropsychological tests such as mini-mental state examination(MMSE), Raven's coloured progressive matrices(RCPM), and frontal assessment battery(FAB). RESULT: Eight cases had an abnormal score on the tests. The volume of hematoma showed a high negative correlation with MMSE scores(p=0.0194)and RCPM(p=0.0338). On the other hand, the volume of hematoma and FAB scores(p=0.0832)were uncorrelated, and the localization of the hematoma did not correlate with tests of cognitive function. CONCLUSION: Cognitive dysfunction is not rare after pontine hemorrhage. Therefore, for patients with infratentorial lesions, it is necessary to perform detailed cognitive functional tests.

Local thrombus formation at the coil-parent artery interface during endovascular coil embolization of cerebral aneurysms.

BACKGROUND AND PURPOSE: Fresh thrombus formation at the coil-parent artery interface around the neck of aneurysms is sometimes observed during coil embolization of cerebral aneurysms. We retrospectively analyzed the factors associated with local acute thrombus formation from the data of patients treated over a period of 5 years at our institute. METHODS: Between November 2004 and March 2009, 242 patients harboring 250 aneurysms were treated with endovascular coil embolization at our institute. The patients were divided into two groups: Group A included 107 patients who were treated and followed up during the initial 29 months of the study, and group B included 135 patients who were treated and followed up during the later 24 months of the study. Clinical and angiographic variables of the procedures were statistically tested for correlation with thrombus formation in the parent arteries. RESULTS: Fresh thrombus formation occurred in six patients with unruptured aneurysms (15%) and 11 patients with ruptured aneurysms (14%) in group A. Among the patients with unruptured aneurysms, the dome-to-neck ratio and location of the aneurysms were independently associated with the risk of thrombus formation, whereas among patients with ruptured aneurysms, a higher World Federation of Neurological Surgeons (WFNS) grade and longer interventional duration were significantly associated with thrombus formation. However, fresh thrombus formation occurred in only two patients with unruptured aneurysms (2.9%) and three patients with ruptured aneurysms (4.4%) in group B. There were no factors that were significantly associated with thrombus formation in all Group B patients. CONCLUSIONS: With regard to coil embolization treatment, anatomical and morphological factors seem to be related to intraprocedural thrombus formation in patients with unruptured aneurysms, whereas duration of the intervention and preoperative status are associated factors in patients with ruptured aneurysms. Careful comparison of the thrombus with control angiograms is important to prevent thrombembolic complications. Moreover, the rate of fresh thrombus formation during coil embolization has decreased over the past 5 years at our institute, suggesting the possibility of lowering the incidence of these complications by early detection and treatment.

Embolization using endovascular technique in acute and chronic stages of traumatic ophthalmic artery aneurysm - case report - .

A 44-year-old man presented with traumatic aneurysm of the left ophthalmic artery. The first coil embolization intervention achieved relatively tight packing of the aneurysm and the parent artery. After 5 months, a second embolization procedure was required because of recurrence of the aneurysm with transition of the intraaneurysmal coil formation. No recurrence occurred after the second embolization. We thought that the first embolization might have prevented catastrophic rupture, whereas the second embolization resulted in complete obliteration of the aneurysm. No entity of the aneurysmal wall formation of the current traumatic aneurysm in the acute stage may have resulted in the recanalization of the aneurysm followed by the second intervention. The stability of the wall in the chronic stage may correlate with the complete obliteration.

[Percutaneous transluminal angioplasty for memory disturbance caused by stenosis of the innominate artery].

It is well known that significant narrowing of the subclavian or innominate artery may cause cerebrovascular ischemic symptoms. We report a case of a 62-year-old man who was suffering from progressive cognitive impairment and was treated by perctaneous transluminal angioplasty (PTA). The patient had undergone aorto-bifemoral bypass, left femoropopliteal bypass, and right femoral artery endoarterectomy. On admission, he was alert, but had memory impairment, especially delayed recall. He complained of dizziness and dysesthesia on his right upper extremity which got worse on exertion. The right radial pulse was diminished and the right brachial blood pressure was lower about 40 mmHg than the left. Angiography demonstrated severe stenosis of the innominate artery near its origin, hypoplasty of the left horizontal anterior cerebral artery segment (Al), and dilation of the left external carotid artery. Left vertebral arteriography revealed retrograde flow of the right vertebral artery in the late arterial phase. Single photon emission computed tomography (SPECT) revealed marked reduction in cerebral blood flow to the left frontal lobe. The patient underwent PTA of the innominate artery with satisfactory results. Cognitive impairment improved remarkably after the angioplasty. The right radial pulse was quite palpable, and the bilateral brachial blood pressures were the same. The cerebral blood flow was increased in SPECT. Memory disturbance can be generated by stenosis of the innominate artery. PTA is one of the effective methods to reverse such cognitive impairment.

[Different types of aphasia caused by cerebral hemorrhage in the left frontal lobe: Broca's aphasia and Broca area's aphasia].

We reported two cases of aphasia that exhibited different characteristics of aphasia following cerebral hemorrhage in the left frontal lobe involving the Broca's area. Case 1 is a 74-year-old right-handed woman. She was hospitalized with speech disturbance. Spontanoues speech was fluent and articulation was normal, but she showed verbal paraphasia and speech perseveration. She demonstrated a preserved ability to repeat short sentences and was able to read words aloud. This type of aphasia is called "Broca area's aphasia". MRI and CT showed hematoma involving the left inferior frontal lobe, operculum and insula cortex. Single-photon emission computed tomography (SPECT) showed low perfusion in the frontal lobe without involvement of the postcentral gyrus. Case 2 is a 76-year-old right-handed man. He was also hospitalized with speech disturbance. Spontanoues speech was non-fluent and articulation was poor. He sometimes showed phonemic paraphasia with anarthria, but he demonstrated a preserved ability to repeat short sentences. He was able to read words aloud in a manner comparatively similar to. This type of aphasia is called "Broca's aphasia". MRI and CT showed hematoma involving the left inferior frontal lobe, operculum and precentral cortex. SPECT revealed low perfusion in the frontal lobe extending to the postcentral gyrus. We supposed that the different characteristics of aphasia in those cases were due to extended lesion in the frontal lobe.

Role of proton magnetic resonance spectroscopy in preoperative evaluation of patients with mesial temporal lobe epilepsy.

A retrospective study was conducted for evaluation of the role of single-voxel proton magnetic resonance spectroscopy (1H-MRS) in preoperative investigation of patients with mesial temporal lobe epilepsy (MTLE). Eighteen cases, including both non-lesional and lesional MTLE, were analyzed. Selective amygdalohippocampectomy was performed in 8 cases, selective amygdalohippocampectomy combined with lesionectomy in 6 cases, lesionectomy in 3 cases, and anterior temporal lobe resection in one case. The length of follow-up varied from 24 to 71 months (median, 35 months). Before surgery, (1)H-MRS disclosed decrease of N-acetylaspartate (NAA) content (P=0.01) and more frequent (P=0.07) presence of lactate (Lac) on the side of the epileptogenic zone. Decrease of NAA content below 0.75 and/or unilateral presence of Lac provided 86% (95% CI: 68%-100%) lateralization accuracy. Metabolic parameters did not differ in subgroups with hippocampal sclerosis and brain tumors. On the long-term follow-up 12 patients (67%) were free of disabling seizures. There was a trend (P=0.05) for worse seizure outcome in cases with significant bilateral metabolic alterations characterized by predominance of choline-containing compounds' peak on 1H-MR spectra on both sides. In conclusion, 1H-MRS-detected reduction of NAA content and unilateral presence of Lac in the mesial temporal lobe structures may serve as additional diagnostic clues for lateralization of the epileptogenic zone in MTLE. Metabolic imaging has limited usefulness for differentiation of the hippocampal sclerosis and low-grade intraaxial brain tumor. Presence of significant bilateral metabolic alterations in the mesial temporal lobe structures is associated with worse postoperative seizure control.

[Embolic complications by ink clots removed from syringes during cerebral angiography].

UNLABELLED: We noted, during cerebral angiography, that the contrast medium was contaminated with numerous small black ink clots from gradation marks on syringes. In this report, we show that ink can be removed from syringes in solid form, and that they may result in embolic complications during cerebral angiography. MATERIALS AND METHODS: To demonstrate that the ink from gradation marks on syringes can come off in a solid form and attach itself to the gloves during cerebral angiography, syringes were gripped many times (just as in an angiographic procedure) after immersion in contrast medium or 0.9% saline for 10 minutes. To see if difference of contrast medium and syringes could affect the removing of ink, five types of nonangiographic syringes and one type of angiographic syringe were rubbed with gauze after certain time periods after immersing them in four kinds of contrast medium or 0.9% saline. RESULTS: Ink attached itself to the gloves in a solid form by repeated gripping due to adherence of contrast medium. Ink was removed from all nonangiographic syringes by rubbing after immersion in any type of contrast medium for two hours. Gradation marks on angiographic syringes were stable with all types of contrast medium. CONCLUSIONS: Thus, ink for gradation marks on nonangiographic syringes, which is easily removed in a solid form due to contrast medium, can be the source of embolic complication during cerebral angiography.