Early Enhancement with Contrast-Enhanced Ultrasonography Relates to the Number of Small-Diameter Neovessels in the Carotid Plaque.

BACKGROUND AND PURPOSE: Intraplaque neovessels (INVs) have been recognized as a major cause of intraplaque hemorrhage and subsequent vulnerability of the carotid plaque. However, the exact mechanisms by which INVs cause intraplaque hemorrhage remain unclear. Various sizes of INVs coexist in carotid plaques pathologically, and we hypothesized that the size of INVs would be associated with carotid plaque histology, particularly in terms of intraplaque hemorrhage. Detection method of INV is important when determining whether carotid plaques are vulnerable, and contrast-enhanced ultrasonography (CEUS) is one of the most useful methods to detect them. The purpose of this study was to examine the relationship between findings from CEUS and vascular pathology obtained by carotid endarterectomy (CEA). We focused on associations between small and large INVs evaluated by CEUS and histologically defined intraplaque hemorrhage. METHODS: Participants comprised 115 patients (mean age, 73.0 ± 7.2 years; 96 men) who underwent preoperative CEUS and underwent CEA. CEUS findings were evaluated as vascular grade at 0 min (Vas-G0) and 10 min (Vas-G10) after contrast injection. Plaques were histologically evaluated quantitatively for the total area of intraplaque hemorrhage, cholesterol, and calcification and the thinnest fibrous cap. Immunohistochemical studies were conducted using anti-CD-34 antibody as a marker for endothelial cells. INVs were divided into two groups depending on diameter: small INVs, <50 µm; and large INVs, ≥50 µm. The numbers of small and large blood vessels in the plaque were quantified histologically. Associations of small and large INVs with CEUS, plaque histology, and clinical findings were assessed by uni- and multivariable analyses. RESULTS: Multivariable analyses indicated that CEUS Vas-G0 was associated with the 4th quartile of the number of small INVs compared with other quartiles, and Vas-G10 was associated with the 4th quartile of the number of large INVs. Histologically, the presence and area of intraplaque hemorrhage were associated with the number of small INVs, while the increased number of large INVs was associated with infrequent plaque disruption and thicker fibrous cap. CONCLUSIONS: Our study showed that early phase enhancement in the CEUS can help identify plaque vulnerability by predicting a larger number of small INVs. This information can also help determine treatment strategies for carotid plaque.

Case report: isolated trochlear nerve palsy associated with posterior cerebral artery aneurysm.

We describe a case of isolated trochlear nerve palsy caused by an unruptured posterior cerebral artery (PCA) aneurysm in an 82-year-old male who consulted an ophthalmologist after developing diplopia. Magnetic resonance angiography showed a left PCA aneurysm in the ambient cistern, and T2WI showed an aneurysm compressing the left trochlear nerve to the cerebellar tentorium. Digital subtraction angiography revealed that the lesion was located between the left P2a segment. We attributed this isolated trochlear palsy to left PCA unruptured aneurysm pressure. Thus, we performed stent-assisted coil embolization. The aneurysm was obliterated, and trochlear nerve palsy improved completely.

A case of pituitary adenoma with infiltration into the sphenoid sinus accompanied by melanocyte proliferation.

A 71-year-old woman presenting with headache and nausea was admitted to hospital. Magnetic resonance imaging revealed a tumorous lesion that surrounded the sella turcica and infiltrated the sphenoid sinus with bone destruction. The tumor was removed by nasal endoscopy. The histology was consistent with pituitary adenoma; immunohistochemistry indicated silent corticotroph adenoma with melanocyte proliferation. The possibility that melanocytes were incorporated into the tumor mass in the sphenoid sinus and underwent proliferation was evaluated by investigating the mechanisms of melanocyte proliferation associated with basic fibroblast growth factor (bFGF) and α melanocyte-stimulating hormone (αMSH). In the normal tissue, the pars intermedia and adrenocorticotropic hormone (ACTH)-producing cells were positive for αMSH. None of the control adenoma tissues were positive for bFGF or αMSH by immunostaining. In the present case, bFGF-positive cells and αMSHpositive cells were observed, suggesting that both may have been involved in melanocyte proliferation. The expression of bFGF has been linked to aggressive disease. Pituitary adenoma with melanocyte proliferation has not been previously reported. Careful follow-up is deemed necessary in the future.

Intracerebral hemorrhage due to vasculitis following COVID-19 vaccination: a case report.

Several vaccines have been approved worldwide for the prevention of morbidity and mortality against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the development of these vaccines has raised concerns regarding their adverse effects. Herein, we report the first case of intracerebral hemorrhage (ICH) due to vasculitis after the first dose of mRNA vaccine (BNT162b2, Pfizer/BioN-Tech). Although this case cannot demonstrate a direct relationship between COVID-19 vaccination and vasculitis, the clinical and histological features of this patient are highly consistent with the adverse effects of COVID-19 vaccine.

[Microneurosurgical Anatomy of the Posterior fossa and Craniocervical Junction].

The posterior fossa is a site where blood vessels and nerves are very dense, so surgery can be very difficult. Therefore, serious sequelae may occur due to complications. Surgeons should be familiar with the complex anatomy of the posterior fossa. This paper outlines the anatomy of the bone, brain, and nerves involved in the surgical approach from the lateral posterior to the cerebellar pontine angle and foramen magnum.

Optimal surgical indications of endoscopic surgery for traumatic acute subdural hematoma in elderly patients based on a single-institution experience.

Recently, treatment of acute subdural hematoma (ASDH) by minimally invasive surgery with endoscopy has been successfully demonstrated. However, few case series are available on this procedure for ASDH, and the surgical indication has not been established. We retrospectively analyzed the data of patients (n = 26) aged 65 years or older who underwent endoscopic surgery (ES) for ASDH at our institution between January 2011 and March 2019. We then evaluated the surgical outcomes and procedure-related complications in patients who underwent ES. The mean hematoma reduction rate was over 90%. Percentage of favorable outcomes at discharge was 69.2% in ES-treated patients. The presence of a skull fracture, subarachnoid hemorrhage, midline shift/subdural hematoma thickness ratio > 1.0, and early surgery were associated with postoperative IPHs in patients who underwent ES or conventional surgery for ASDH. The present study revealed that ES for elderly patients with ASDH is likely to be an efficient and safe procedure when patients are selected appropriately. However, ES is not recommended in patients with significant IPHs on initial CT scan. Additionally, ES should be carefully considered in cases with the factors, where IPHs may progress following surgery.

Detection and Differentiation of Dural Arteriovenous Fistulas in the Transverse Sinus/Sigmoid Sinus and Cavernous Sinus Using Carotid Ultrasound: Importance of Evaluation of the Occipital Artery.

OBJECTIVES: Dural arteriovenous fistula (DAVFs) in the transverse sinus (TS)/sigmoid sinus (SS) and cavernous sinus (CS) are observed frequently in the clinic. This study aimed to detect DAVFs with ultrasound and compare carotid ultrasound findings between these conditions. METHODS: We retrospectively reviewed 26 patients with either a TS/SS DAVF or a CS DAVF who were admitted to our hospital for evaluation of DAVFs from 2014 to 2018. The shunt site decision was made by neuroendovascular experts, whereas carotid ultrasound examinations were performed by ultrasound specialists. The flow velocity of the ipsilateral external carotid artery was reviewed in all 26 patients, whereas that of the occipital artery (OA) was examined in 20 patients. Blood flow velocities were compared between the TS/SS DAVF and CS DAVF groups. RESULTS: The study included 18 patients with a TS/SS DAVF (11 women and 7 men; mean age ± SD, 65.3 ± 18.6 years) and 8 patients with a CS DAVF (7 women and 1 man; mean age, 70.4 ± 9.3 years). Evaluations of feeder arteries on cerebral angiography showed that all patients had dural branches from the internal carotid and middle meningeal arteries as feeders of CS DAVFs, whereas the OA was the major feeder source of all TS/SS DAVF cases. The end-diastolic velocity (EDV) of the external carotid artery was significantly higher in patients with a TS/SS DAVF compared with those with a CS DAVF (P = .004). The EDV of the OA was significantly elevated in TS/SS DAVF cases compared with CS DAVF cases (P < .001). CONCLUSIONS: Duplex ultrasound parameters are significantly different between patients with TS/SS and CS DAVFs. An increased EDV of the OA can predict the presence of a TS/SS DAVF.

Clinical features of middle cluneal nerve entrapment neuropathy.

BACKGROUND: Entrapment of the middle cluneal nerve (MCN), a peripheral nerve in the buttock, can elicit low back pain (LBP). We examined the epidemiology, clinical course, and treatment of MCN entrapment (MCN-EN). METHODS: Among 383 LBP patients who visited our institute, 105 were admitted for intractable LBP. They were 42 men and 63 women; their average age was 64 years. Based on clinical symptoms, palpation, and the effects of MCN block, we suspected MCN-EN in these 105 patients, 50 of whom are our study subjects. Their treatment outcomes were assessed at the time of discharge and at follow-up visits. RESULTS: MCN-EN was diagnosed in 50 of the 383 patients (13.1%) and they were hospitalized. In 43 (11.2%), MCN-EN was associated with other diseases (superior cluneal nerve entrapment, n = 21, sacroiliac joint pain, n = 9, other, n = 13). At the time of discharge, the symptoms of patients with LBP due to MCN-EN were significantly improved by repeat MCN blocks. In 7 of the 383 patients (1.8%), LBP was improved by only MCN blocks; 5 of them had reported leg symptoms in the dorsal part of the thigh. After discharge, 22 of the 50 hospitalized patients required no additional treatments after 2-5 blocks; 19 required only conservative treatment, and 9 underwent microsurgical release of the MCN. CONCLUSIONS: We confirmed MCN-EN in 50 of 105 patients admitted for intractable LBP. Repeat MCN blocks were effective in 22 patients; 19 required additional conservative treatment, and 9 underwent surgery. Buttock pain radiating to the posterior thigh was an MCN-EN symptom that has been diagnosed as pseudo-sciatica. Before subjecting patients with intractable LBP to surgery, the presence of MCN-EN must be ruled out.

High-frequency thermal coagulation to treat middle cluneal nerve entrapment neuropathy.

OBJECTIVE: Middle cluneal nerve entrapment (MCN-E) around the sacroiliac joint can elicit low back pain (LBP). Pain control can be obtained with anesthetic nerve blocks; however, when their effectiveness is transient, surgical release may be necessary. We investigated the efficacy of radiofrequency thermocoagulation (RFTC) in patients with MCN-E. METHODS: Between December 2018 and August 2019, 11 consecutive patients (4 men, 7 women; mean age 76.4 years) with intractable medial buttock pain due to MCN-E underwent MCN RFTC. The mean symptom duration was 49.5 months; pre-RFTC local MCN blocks provided pain relief for a mean of 7.7 days. The severity of pain in the medial buttock due to MCN-E was recorded before and 2, 6, 12, and 24 weeks after RFTC on the numerical rating scale (NRS) and the Roland-Morris Disability Questionnaire (RDQ). RESULTS: All patients reported pain alleviation; there were no complications. While there was a significant difference in the pre- and post-RFTC treatment NRS (p < 0.05), the RDQ scores were significantly lower only after 12 weeks. The duration of pain relief was significantly prolonged by RFTC (p < 0.05). Two patients suffered pain relapse 10 weeks post-RFTC; pain alleviation was obtained by re-RFTC performed 2 weeks after pain recurrence. Two other patients relapsed 20 and 21 weeks post-RFTC; their symptoms also disappeared by MCN block administered 24 weeks after they had undergone RFTC. CONCLUSION: RFTC may safely control intractable LBP due to MCN-E.

[Surgical Technique of Ventral Intermediate Thalamic Deep Brain Stimulation].

Deep brain stimulation(DBS)of ventral intermediate(Vim)thalamic nucleus is an established procedure for tremor disorders, however, there are technical variations among specialists. The most common indications of Vim DBS are essential tremor(ET)and tremor dominant Parkinson's disease(PD), and less commonly other tremor disorders including Holmes tremor are treated with the same procedure. The variations of the surgical technique exist in the preoperative imagings and planning of the DBS electrode trajectory. In this review, we explain about the basic concept of Vim DBS and our surgical method.

[A Case of Radiation Necrosis in the Right Occipital Lobe Accompanied with Massive Hemorrhage:Histopathological Analysis].

Radiation necrosis with massive hemorrhage is a rare complication of radiotherapy. We report the case of a male patient who had undergone radiotherapy therapy 18 years earlier and presently underwent gamma knife radiosurgery for a metastatic brain tumor in his right occipital lobe. The patient showed aberrant behavior with left homonymous hemianopsia and a gradual deterioration of cognitive function after radiotherapy. A CT scan showed the presence of an intracerebral hematoma over the right occipital lobe with mass effect, and small spotty enhancements on the lesion when enhanced on gadolinium contrast-enhanced MRI. Intraoperative findings revealed necrosis of the occipital surface and a hematoma in the occipital lobe. Pathological findings showed damage to the walls of the sinusoidal capillaries and vitreous degeneration of the inner membrane with a spongiform hemangioma. After surgery, the cerebral edema resolved, and the patient's clinical symptoms improved. The cause of the radiation necrosis and bleeding in this patient was assumed to be due to the breakdown of the congested walls of the sinusoidal capillary vessels.

[Microvascular Decompression to Treat Abducens Nerve Paralysis Caused by Compression of the Anterior Inferior Cerebellar Artery:A Case Report].

Microvascular decompression(MVD)is an effective treatment for hemifacial spasm and trigeminal neuralgia. However, there are few reports regarding its use with abducens nerve palsy. Here, we report the case of a 77-year-old male who presented with diplopia and was admitted to our facility for right abducens nerve palsy. MRI constructive interference in steady-state(CISS)showed that the right anterior inferior cerebellar artery(AICA)was curved in a posterior-superior direction at the beginning of the region of origin, causing compression of the root exit zone of the right abducens nerve. In addition, MRI showed an unruptured fusiform aneurysm(5.3mm×7.1mm)of the vertebral artery(VA)involving the posterior inferior cerebellar artery(PICA). However it was not related to abducens nerve paralysis. The aneurysm was successfully treated with an occipital artery-posterior inferior cerebellar artery(OA-PICA)bypass and clipping of the proximal VA and PICA origin. The position of the offending artery was moved using a Teflon® felt fibrin glue and the retrosigmoid transcondylar fossa approach. The patient recovered from abducens nerve paralysis with no new neurological deficit. We emphasize the importance of choosing an appropriate approach as this increases the possibility of treating abducens nerve paralysis in a timely manner.

Three-dimensional spin-echo-based black-blood MRA in the detection of vasospasm following subarachnoid hemorrhage.

BACKGROUND: Black-blood MR angiography (BBMRA), which utilizes a non-T1 contrast spin-echo type technique, has been expected to overcome several issues associated with time-of-flight (TOF) MRA. PURPOSE: To investigate the efficacy of BBMRA to detect vasospasms following subarachnoid hemorrhage (SAH). STUDY TYPE: Retrospective. SUBJECTS: Seventeen patients with SAH in their early posttreatment period. FIELD STRENGTH/SEQUENCE: BBMRA, which uses a volumetric isotropic turbo spin-echo acquisition (VISTA), and TOF-MRA on 1.5T scanners. ASSESSMENT: Visualization of supratentorial arteries and veins in BBMRA was rated on a 4-point scale by two neuroradiologists. Another neuroradiologist independently assessed TOF-MRA. The degree of the vasospasm was then evaluated using a 3-point scale by the same readers. The diagnostic performance of the MRAs was evaluated using computed tomography angiography (CTA) or digital subtraction angiography (DSA) as the standard of reference. STATISTICAL TESTS: Wilcoxon signed rank test, McNemar test, and Cohen's kappa coefficient. RESULTS: BBMRA provided superior visualization of the anterior and middle cerebral arteries than TOF-MRA (P < 0.05). The depiction of the veins was more pronounced on BBMRA (P < 0.01). Of the 166 arterial segments evaluated by CTA or DSA, 23 (13.9%) could not be assessed using TOF-MRA because of high signal hemorrhage, whereas BBMRA enabled visualization of all the segments. Vasospasm was confirmed in 30 segments by CTA or DSA. The sensitivity, specificity, and positive and negative predictive values were 73, 96, 76, and 95 for TOF-MRA and 91, 100, 100, and 98 for BBMRA, respectively (P = 0.13 for sensitivity, P = 0.06 for specificity). The agreement of the degree of vasospasm between MRA and the standard of reference, as indicated by kappa value, was 0.71 (95% confidence interval [CI], 0.55-0.87) for TOF-MRA and 0.91 (95% CI, 0.82-0.99) for BBMRA. DATA CONCLUSION: BBMRA, owing to its contrast properties, may be superior to TOF-MRA for the evaluation of intracranial arteries after SAH. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:800-807.

The Comparison of Clinical Findings and Treatment Between Unilateral and Bilateral Vertebral Artery Dissection.

BACKGROUND: There are limited clinical studies of bilateral vertebral artery dissection (VAD). OBJECTIVE: To compare the characteristics, imaging findings, and treatments between patients with bilateral and unilateral VAD. METHODS: Between February 2007 and May 2017, 31 (mean age: 53.0 years; 23 men, 8 women) out of 171 VAD patients were hospitalized because of bilateral VAD. Onset type, dissection site, dominant side of the VA, imaging features, treatments, and outcomes were investigated based on medical records. The dominant side of the VA was determined by basi-parallel anatomical scanning. RESULTS: Twenty (64.5%) of 31 patients exhibited bilateral VAD on both sides of V4. The dominant side of the VA was right in 16 patients and left in 15 patients. The pearl and string sign (an angiographical finding with both dilatation and stenosis) was frequently observed on the dominant VAD side, while a tapered occlusion and string sign were most common on the nondominant side. For clinical subtype of VAD, 6 (19.4%) patients had subarachnoid hemorrhage, 10 (32.3%) ischemic stroke, 3 (9.7%) infarction plus subarachnoid hemorrhage, and 12 (38.7%) only headache. The frequency of infarction was increased in bilateral VAD compared with unilateral (P < .05). Surgical intervention was performed in 3 cases, while 14 patients received endovascular intervention. CONCLUSIONS: Infarction occurred frequently in bilateral VAD patients, and 17 patients required an intervention (mainly endovascular) for VA. The treatment strategy varied depending on the clinical subtype, imaging findings of VAD, and morphology of the dominant VAD side.

[Cervical Myelopathy Caused by Chronic and Intermittent Cord Compression by Tumors upon Neck Rotation:A Case Report].

A 35-year-old man with neurofibromatosis type I presented with right arm weakness and gait disturbance that had developed gradually. MR imaging revealed bilateral intra-and extradural tumors at the C1-2 level. Although the adjacent spinal cord was narrowed, there was no evident contact between the tumors and the spinal cord. Computed tomography myelography revealed that the tumors compressed the cord only during neck rotation. The tumors were resected to make an abundant subdural space around the affected cord. The patient's neurological symptoms improved postoperatively. Because contact between the masses and spinal cord only occurred upon neck rotation, we believe it is important to consider the possibility of intermittent compression, termed dynamic rotational canal stenosis, in patients with masses at the C1-2 level, even when such masses are not seen to be in contact with the cervical cord on routine radiological examination.

[A Case of Meningeal Solitary Fibrous Tumour/Haemangiopericytoma WHO Grade III Metastasized to the Spleen Shortly After Tumor Resection].

Revision of WHO guidelines in 2016 led to the classification of solitary fibrous tumours(SFTs)and haemangiopericytomas(HPCs)as a single tumor entity characterized by NAB2-STAT6 fusion. Standard-of-care treatment involves surgery, but local recurrence and distant metastasis sometimes occur. The average latency to metastasis after surgery is 99 months. A 38-year-old female patient presented with a complaint of headache. An 8×5×2cm lesion showing Gd-T1 enhancement was detected near the superior sagittal sinus. Pathological assessment following resection revealed proliferating, polymorphic, atypical tumor cells with distinct nucleoli in a "patternless pattern." Cellularity was moderate to high, and mitotic figures were observed in 15/10 high power fields. Immunohistochemically, tumor cells tested positive for STAT6, and RT-PCR revealed a NAB2-STAT6 fusion gene(exons 6 and 17, respectively), supporting a diagnosis of SFT/HPC WHO grade III. Despite postoperative radiotherapy, multiple metastases to the spleen were detected 8 months after surgery, and distal pancreatectomy with splenectomy was performed. The pathology of the splenic tumor was similar to that of the intracranial tumor. Recurrent disease in a lymph node was detected 1 month later, and local radiation therapy was administered. The patient died of cancerous peritonitis 5 months later. In this case, exceedingly rapid metastasis to the spleen occurred, despite the administration of vigorous treatment. Here, we review SFT/HPC incidence, treatment, and outcomes to better understand this rare malignancy.

Intra-Plaque Vessels on Contrast-Enhanced Ultrasound Sonography Predict Carotid Plaque Histology.

BACKGROUND AND PURPOSE: Although the echogenicity of carotid plaques on carotid enhanced ultrasound (CEUS) was reported to correlate with the historological density of intra-plaque neovessels, it is unclear whether the intra-plaque vessel size is associated with carotid plaque vulnerability. We evaluated the relationship of size of intra-plaque vessels on CEUS with carotid plaque histology. METHODS: We prospectively registered patients with carotid stenosis who were hospitalized to receive carotid endarterectomy between 2012 and 2016. CEUS was performed by ultrasound specialists using a 7-MHz linear transducer (GE LOGIQ7; GE Healthcare, Milwaukee, WN, USA). Sonazoid® was used for conducting CEUS. The sizes of microbubbles inside the plaques were scored at 0, 1, 3, and 5 min after the injection of contrast agent, and were categorized according to our defined vascular score (Vas-S; 0: the effect of contrast was not recognized; 1: the microbubbles were visible, but so blurred and vague that their shape could not be recognized; 2: dot or string-like microbubbles with movement, localized in part or the whole site of the plaque). At histological examination, we simplified the modified American Heart Association classification and defined as an atherosclerotic category (Ath-cat; 1: unruptured plaque; 2: ruptured plaque; 3: healed plaque). We then assessed the correlation of Vas-S with Ath-cat, which describes the process of rupture and restoration of carotid plaques. RESULTS: A total of 97 patients were included in this study. A higher Ath-cat was significantly associated with higher Vas-S at any time. Spearman signed-rank test indicated that Vas-S at 1 min was most strongly correlated with Ath-cat (ρ = 0.43, p = 0.001). Receiver operating curve analysis indicated that a Vas-S of 0 at 1 min was significantly associated with an unruptured plaque (area under curve [AUC] 0.72, p = 0.006), while a Vas-S of 2 at 1 min was significantly associated with a healed plaque (AUC 0.72, p = 0.001). CONCLUSION: Vas-S values of 0 and 2 at 1 min indicated unruptured and healed plaques respectively. Thus, a Vas-S of 1 at 1 min is an indicator of a ruptured plaque. The intra-plaque vessel size on CEUS was significantly associated with carotid plaque histology, and may predict the process of plaque rupture and restoration.

Potential of Hybrid Assistive Limb Treatment for Ataxic Gait Due to Cerebellar Disorders Including Hemorrhage, Infarction, and Tumor.

Cerebellar hemorrhage (CH) is a severe life-threatening disorder, and surgical treatment is often required in an emergency situation. Even in cases in which the surgical procedure is successful, functional recovery is likely to be delayed because of cerebellar symptoms such as ataxia and gait disturbance. Here, we briefly review the efficacy of hybrid assistive limb (HAL) treatment in neurosurgical practice and propose a new comprehensive treatment strategy for CH to facilitate early neurological recovery. We have experienced cases of ataxic gait due to various etiologies, treated with rehabilitation using the HAL, and our data showed that HAL treatment potentially improves ataxic gait and balance problems. HAL treatment seems to be an effective and promising treatment modality for selected cases. Future studies should evaluate gait appearance and balance, in addition to walking speed, to assess improvement in cerebellar symptoms.

Cerebral and spinal cavernomas associated with Klippel-Trenaunay syndrome: case report and literature review.

Klippel-Trenaunay-Weber syndrome (KTWS) involves a triad of conditions, including cutaneous hemangiomas, venous varicosities, and osseous and soft-tissue hypertrophy of the affected limb. We describe a rare case of multiple cavernomas in the central nervous system in a patient with KTWS. A-64-year-old man with KTWS and a previous brain hemorrhage presented with sudden onset of gait and vesicorectal disturbance. The magnetic resonance imaging scan showed a cavernoma associated with hemorrhage in his lumbosacral spinal cord. Moreover, numerous cavernomas were identified in his brain. He was treated conservatively with no adverse events. Gait disturbance improved, but vesicorectal disturbance did not improve.

Safety and Feasibility of Carotid Artery Stenting with Dual-Echo Technique to Minimize Iodinated Contrast Dose.

BACKGROUND: The aim of this study was to evaluate the safety and feasibility of carotid artery stenting (CAS) employing dual-ultrasound technique and administering a minimal contrast agent in patients with renal insufficiency. METHODS: Between September 2009 and July 2013, 63 consecutive patients underwent CAS at our institution: dual-echo carotid artery stenting (DECAS) in 7 patients with renal insufficiency and standard carotid artery stenting (STCAS) in the remaining 56 patients. Periprocedural adverse events and outcomes were compared between the 2 groups. RESULTS: Technical success was achieved in all cases. The 3 procedure-related complications were 1 case of transient hemiparesis in the DECAS group and 1 transient and 1 permanent case of hemiparesis in the STCAS group. The rate of positive diffusion-weighted-imaging lesions did not differ significantly between the 2 groups (28.6% versus 12.5%, P = .26). A significantly smaller volume of contrast was used in DECAS (15 versus 163 mL, P < .01). The change in creatinine level remained stable after CAS and did not differ between the 2 groups (.02 versus .03 mg/dL, P = .96). CONCLUSIONS: DECAS is safe and feasible for patients with pre-existing renal insufficiency and can provide an alternative for patients with carotid stenosis and renal insufficiency.