Endotracheal Tube Obstruction Experienced during an Anterior Cervical Discectomy and Fusion.

During anterior cervical discectomy and fusion (ACDF), endotracheal tube difficulties are anticipated at the operative level but are unexpected elsewhere in the airway. We report the case of a 66-year-old woman who underwent C4/C5 ACDF to treat adjacent segment disease following a previous anterior cervical fixation surgery. Shortly after her lower jaw was elevated and the fusion cage was inserted, a rise in airway pressure was observed, indicating impaired breathing. Subsequent examination revealed a bent endotracheal tube in the oral cavity as the cause of the respiratory impairment. During anterior cervical surgery, elevating the lower jaw can cause the tongue root to press against the endotracheal tube. Reinforced endotracheal tubes, with a spiral-wound wire in the inner wall, would effectively prevent this issue. In the unlikely event of impaired breathing during such an operation, the oral cavity should be inspected for confirmation of an open airway.

Double Crush Syndrome of the Lower Limb in L5 Radiculopathy and Peroneal Neuropathy: A Case Report.

Double crush syndrome (DCS) is a clinical condition involving impingement of the spinal and peripheral nerves. DCS of the lower limbs has been recognized; however, no detailed reports have been published. Herein, we report a rare case of the coexistence of L5 radiculopathy and peroneal nerve entrapment neuropathy. The patient suffered from pain in the left lower leg and left foot combined with muscle weakness in the left leg without a Tinel-like sign in the peroneal tunnel area. MRI showed a deficit in the left L5 nerve root sleeve, and X-ray imaging revealed L5 spondylolysis. Lumbar fusion surgery was performed at L5-S1. Subsequently, the patient's symptoms were partially improved, but the pain and toe and ankle motor weakness persisted. In addition, a Tinel-like sign appeared at the entrapment point of the peroneal nerve. The entrapped peroneal nerve was decompressed, and the patient's symptoms improved. The patient had L5 radiculopathy owing to the improvement in his symptoms in the upper leg before and after lumbar surgery. It is unclear why no Tinel-like sign was detected before the first surgery, but we hypothesized that L5 nerve disorder may mask the symptoms triggered by compression of the peroneal nerve due to the complex pathology of DCS and dynamic factors. Distinguishing between radiculopathy and relative peripheral neuropathy should always be a consideration. DCS may mask characteristic symptoms, and it is important to carefully follow up the patient to detect changes in his or her condition.

Initial Clinical Experience of Using a Newly Designed Preshaped Microguidewire in Acute Endovascular Thrombectomy.

Mechanical thrombectomy has been widely used for the treatment of acute ischemic stroke. During this procedure, operators must navigate the microcatheter with a microguidewire (MGW) into vessels that cannot be visualized on fluoroscopy as rapidly as possible. In this study, we developed a modified pigtail-shaped MGW (MPMGW) for security and controllability. Moreover, the efficacy of the MPMGW for the treatment of acute ischemic stroke was assessed. The MPMGW was designed using 0.014 MGW. Because we created four MPMGWs during a clinical evaluation before the launch in the market, these wires were used in four consecutive patients with acute ischemic stroke in the single institution. The occluded arteries were the basilar artery (n = 1), middle cerebral arteries (M1 and M2, n = 2), and internal carotid artery (n = 1). All four procedures were conducted without any complications. The procedures included navigating the MGW and passing it through the clot. Complete recanalization was achieved in all cases. The average time between femoral artery puncture and recanalization was 15 min. The use of the preshaped MPMGW in acute thrombectomy was effective in terms of both security of procedure and reduction in recanalization time.

Spinal Epidural Hematoma Associated with Epidural Metastasis After Minor Trauma.

BACKGROUND: Spinal epidural hematoma associated with epidural metastasis is very rare. Epidural hematoma is unusual in itself, and metastatic epidural tumors do not commonly occur. CASE DESCRIPTION: A 76-year-old man with a medical history of untreated stage III rectal cancer and chronic obstructive pulmonary disease underwent emergency spine surgery for acute development of severe quadriplegia due to cervical epidural hematoma after minor indirect trauma. Hemorrhagic lesions, such as yellow ligaments, were accompanied by hematomas that adhered to the dura mater and were confirmed on pathology to be small cell carcinoma. Some nodules were detected in the right pulmonary hilar lesion and pleural lesion on computed tomography, and stage IV small cell carcinoma was diagnosed. CONCLUSIONS: To our knowledge, spinal epidural hematoma accompanied by epidural metastasis has not previously been reported. We hypothesized that tissue invasion of malignant neoplasms may cause hemorrhagic conditions. The presence of a tumor should therefore be considered in the differential diagnosis of cases of epidural hematoma.

A Novel Technique for Microcatheter Additional Shaping During Intracranial Aneurysmal Coil Embolization: Microcatheter Shaping Cast.

BACKGROUND: When a shaping mandrel is inserted into the tip of a preshaped microcatheter, the existing curve becomes uncertain because the tip is straightened by the inner mandrel. Therefore, we developed a way to perform microcatheter shaping by means of an external cast, which we named "microcatheter shaping cast." TECHNIQUES: A shaping mandrel attached to a microcatheter was used and coiled 4-5 times around a metallic introducer, which was attached using a microguidewire. Then, a stent-like handmade cast was prepared. After the microcatheter tip was inserted into the cast, it was manually bent according to the aneurysmal shape and size. The tip and cast were heated with a hot air gun. We evaluated the relationship between degrees of bending and heating time to achieve appropriate right-angled shaping memory. CONCLUSIONS: The presented microcatheter shaping method should be more useful than conventional internal shaping, especially in cases that require an additional microcatheter shaping or reshaping during aneurysmal coil embolization.

A novel approach involving a microcatheter tip during aneurysmal coil embolization: The Γ (gamma) tip method.

Complete and secure occlusion of the entire aneurysmal neck remains a problem despite major advances in the treatment of intracranial aneurysms using endovascular coil embolization. Here, we present our initial clinical experience using a novel strategy for endovascular coil embolization involving a microcatheter tip, known as the "Γ (gamma) tip method," and compare the in vitro results of this technique with those of conventional straight microcatheters. The microcatheters were bent at a right angle starting 1-2 mm from the length of the tip using a catheter-shaping mandrel and a hot air gun. The tiny right-angled tip is the "Γ tip." In aneurysm models, we assessed the efficacy of shaping during coil deployment. The Γ-tipped microcatheters demonstrated better movement and oscillation during insertion of the coil into the aneurysm compared with the straight-tipped catheters. Moreover, the Γ-tipped microcatheter provided less coil protrusion into the parent artery and less microcatheter kickback compared with the straight tip. With the Γ-tipped microcatheter, even if the first coil loop migrated into the parent artery, its subsequent dynamic movement routed it back into the aneurysm. The Γ tip method enabled smooth movement of the microcatheter into the aneurysm, demonstrating the safety and security of coil insertion using the Γ tip compared with the conventional straight tip.

Efficacy of three-dimensional rotational fluoroscopic unit guidance for lumbar cerebrospinal fluid drainage among patients with unsuccessful initial attempt at bedside.

Lumbar cerebrospinal fluid drainage has been widely performed in patients at the bedside; however, technical failure can occasionally occur as a result of blind maneuvering. Herein, we present the use of rotational fluoroscopic unit-guided lumbar drainage for patients with an unsuccessful initial attempt at bedside. In four of the 24 patients with aneurysmal subarachnoid hemorrhage, initial lumbar drainage could not be performed at bedside. Thus, a three-dimensional rotational technology guided by a high-quality fluoroscopic unit was used. After a cone-beam computed tomography scan was performed, an accurate puncture point and a target thecal sac were identified using the software. The fluoroscopic unit helped us to identify the puncture point and trajectory with a laser pointer on the patient. A needle was inserted along the tract until the cerebrospinal fluid was collected. The lumbar drainage tube was successfully inserted with a single puncture in all four patients. Rotational fluoroscopic technology helps to identify a suitable puncture point, trajectory and target site for lumbar spinal drainage. Our technique is considerably useful in an era wherein minimally invasive procedures are preferred.

Novel Operation Support Robot with Sensory-Motor Feedback System for Neuroendovascular Intervention.

BACKGROUND: Robotic technology is rapidly developing in the medical field, particularly contributing to support operative intervention using the da Vinci system during endoscopic surgery. Neuroendovascular intervention robot surgery is preferred when aiming to reduce radiation exposure among surgeons. METHODS: We developed a prototype of a support robot with 2 independent slaves manipulating both the microcatheter and microguidewire connected with the remote master driver with 2 joysticks. This design simulates usual catheterization with both hands. The slave manipulator has a sufficient output force >1 N to reproduce the exact master intervention without slip and delay. This machine has a unique function that indicates the reaction force of the resistance on wire stuck using the sensor system. We investigated the master-slave response, reliability of the force gauge, and degree of slippage of the slave motion on the table and checked the controllability, safety, and reproducibility of microcatheterization and insertion maneuver into the experimental aneurysm in the in vivo silicone vessel model. RESULTS: We realized the well master-slave response with a stable driving speed of the microguidewire at approximately 1 mm/s and with linear correlation between the output voltage and driving force. Also, we confirmed the well safety function to avoid the overloading to the vascular wall with the slippage of the slave roller on loading >1 N pushing force. Successful microcatheterization and insertion into the aneurysm model was performed in the wet vascular model corresponding to the 3-dimensional handling without excessive stress to the vascular or aneurysmal wall. CONCLUSIONS: Neuroendovascular intervention requires delicate power adjustment with fine finger control. Our support robot for neuroendovascular interventions demonstrated the accurate reproducibility of the operator's maneuver and safe operation in the vascular model using the sensor system. This system will realize the neurointervention without human operators in the AngioSuite and may facilitate telesurgery with remote control in the near future.

Endovascular Embolization of Sinus Pericranii Using Plastic Cup During Glue Injection.

BACKGROUND: Sinus pericranii (SP) is a rare abnormal connection between the intracranial and extracranial venous drainage pathways through the osseous channels. Herein we present the case of a patient with growing SP, which was successfully treated using endovascular transvenous embolization through external compression with a plastic cup for preventing glue migration into subcutaneous veins. CASE DESCRIPTION: A 9-month-old boy presented with a gradually growing mass on the midline cranial vertex after his birth, for which transvenous embolization was performed. A microcatheter was successfully navigated into the SP from the superior sagittal sinus. Because the subcutaneous drainages were confirmed to be multidirectional, we compressed the drainages through the skin using a plastic cup during the glue injection step for preventing glue migration. Subsequently, the SP was completely obliterated. The postoperative course was uneventful. CONCLUSIONS: Manual compression using a plastic cup was useful not only for embolization but also for reducing the physician's exposure to radiation as compared with that in the finger compression method. When a direct puncture is required, a plastic cylinder can also be used.

Reliability of an Intraoperative Radiographic Anteroposterior View of the Spinal Midline for Detection of Pedicle Screws Breaching the Medial Pedicle Wall in the Thoracic, Lumbar, and Sacral Spine.

OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity of using the spinal midline (M line) on a radiographic anteroposterior (AP) view for detecting pedicle screws (PSs) breaching the medial pedicle wall. METHODS: We retrospectively reviewed 145 patients who underwent fusion surgery using PSs between January 2006 and May 2017. We defined the M line as a line that connected the upper and lower spinous processes through the fixed vertebrae. The M line was positive if the tip of the PS crossed the M line. The reference standard was a computed tomography scan. The reliability of the M line was examined. RESULTS: The subjects included 145 patients (70 men and 75 women; mean age, 63.4 years). A total of 599 PSs were examined. Most cases were because of spondylolisthesis (66.9%). Most screws were inserted at a lower lumber level (77.6%). Analysis of the diagnostic accuracy of the M line yielded a sensitivity of 74.1% and a specificity of 95.3%. In addition, the positive predictive value of the M line was 42.6%, and the negative predictive value of the M line was 98.7%. CONCLUSIONS: Assessment of the M line via an intraoperative radiographic AP view is a simple, readily available, complementary method for detecting PSs that have breached the medial pedicle wall in the thoracic, lumbar, and sacral spine. In particular, the M line has a strong negative predictive value, which is much more meaningful.

A Novel Technique for Stent-Assisted Coil Embolization of Intracranial Aneurysms: The Wireless Trans-Cell Approach.

BACKGROUND: When inserting coils under stent deployment, a jailed microcatheter technique is typically applied as a first line approach. However, the trans cell approach might be required to achieve satisfactory complete occlusion. The trans cell approach occasionally ends in failure because the catheter cannot safely follow a proceeding guidewire into the aneurysm. Here, we report the new wireless trans cell approach (WTA), which allows feasible and safe catheter navigation through the stent strut into the aneurysm, without a proceeding guidewire. METHODS: A straight tip microcatheter was used, and the tip was shaped as a very small bend of approximately 45°. The side aspect of the catheter tip exhibited a right angled edge, while the front aspect showed a round curve in the advancing direction. We compared the 45° microcatheter with a straight tip microcatheter using a silicon vascular model and then applied the WTA in a case of an unruptured basilar apex aneurysm. RESULTS: Catheter navigation through the stent strut was smoother with the WTA than the conventional wire assisted approach. Our case of a basilar apex aneurysm was successfully treated with the dual catheter technique, which involved a jailed catheter and navigation using the WTA. After stent deployment from the right posterior cerebral artery to the basilar artery through the 45° microcatheter, the WTA was applied using the same catheter. No stress was detected during catheter navigation through the stent strut into the aneurysm. CONCLUSIONS: The WTA is associated with smoother catheter navigation compared with the conventional wire assisted approach in cases of a terminal type aneurysm.

Novel Technique for Rapid and Accurate Insertion of a Microguidewire Tail Into Low-Profile Devices During Endovascular Procedures: The Paper Rail Method.

PURPOSE: To report a novel technique ("paper rail") to facilitate inserting the tail of a microguidewire into the tip of a low-profile device during endovascular procedures. TECHNIQUE: A sterilized nonwoven fabric tape with a smooth glossy paper backing is used. The tape has several linear folds ideal for a paper rail. Holding each piece of equipment about 5 cm from its respective tip, both the tail of the guidewire and the tip of the catheter are navigated at a 30° angle toward each other in the crease until the guidewire enters the catheter. The paper rail technique was compared with the conventional freehand method under varying luminosities found in an operating room. The paper rail technique was most effective in suboptimal lighting, where the mean time was reduced from 83 seconds with the conventional method to 20 seconds with the paper rail maneuver. The times required to insert the wire with the paper rail method were comparable (~22 seconds) at all light levels. CONCLUSION: The paper rail method may help improve the speed and accurate insertion of the tail of a microguidewire into the tip of low-profile devices during endovascular procedures. It may be particularly useful for physicians in a low-light environment or trainees.

Neonatal Intracranial Pial Arteriovenous Fistula Treated with Endovascular Embolization: A Case Report.

BACKGROUND: Pial arteriovenous fistulas (PAVFs) are rare vascular malformations, especially in neonates. The purpose of this report is to discuss the treatment strategy and its associated challenges. We present a case of prenatal intracranial PAVF treated by endovascular embolization in the neonatal period. CASE DESCRIPTION: The patient was born through Cesarean delivery and then treated twice using transarterial embolization with detachable platinum coils and n-butyl cyanoacrylate due to intractable heart failure. Even though angiography findings showed dramatical reduction in the shunt, the patient did not recover from heart failure and died at day 49 after birth. CONCLUSIONS: Despite current developments in medical technology and therapies, the effective treatment of critical PAVFs still poses a challenge. Therefore, more indications and effective alternative treatments must be discussed.

Novel Vertebral Artery Flow Reversal Method for Preventing Ischemic Complication during Endovascular Intervention.

BACKGROUND AND PURPOSE: We report a secure endovascular approach for the treatment of vascular lesions of the posterior circulation. Even if a large profile guide catheter is wedged in the unilateral vertebral artery (VA), our VA flow reversal method can prevent ischemic complications, including the spinal cord infarction. CASE PRESENTATION: The patient was a 64-year-old woman who had been followed up for arteriovenous malformation (AVM) and an unruptured aneurysm of the basilar artery-superior cerebellar artery bifurcation. Endovascular treatment was performed because minor bleeding occurred from the AVM. When a 6-French guide catheter was navigated into the right VA, the guide catheter became completely wedged, and blood flow between the tip of the catheter and the VA union was fully stagnated. Because ischemia of the anterior spinal artery and right posterior inferior cerebellar artery could persist for a few hours during the endovascular procedure, we built a continuous reversal circulation from the guiding catheter tip to the femoral vein. The flow stagnation disappeared immediately. There was no complication during embolization of both the AVM and aneurysm. CONCLUSIONS: The VA flow reversal method was secure in this case in which the tip of the guide catheter became wedged in the VA during the endovascular procedure.

Efficacy of the proximal balloon flow control method for endovascular coil embolisation as a novel adjunctive technique: A retrospective analysis.

Background and purpose In our previous study, we established the utility of 8-F balloon guide catheters for anterior circulation aneurysms. This study aims to assess the efficacy of the proximal flow control method using 8-F balloon guide catheters for coil deployment into the aneurysms as a novel adjunctive technique for aneurysmal coil embolisation along with local balloon neck remodeling, stent assist and double catheter techniques. Materials and methods We retrospectively analysed patients who underwent endovascular coiling of anterior circulation aneurysms between August 2013 and December 2017. Results Of 206 patients enrolled in this study, the balloon of the guiding catheter was inflated to assist coil deployment in 43 patients (20.9%). In addition, the proximal flow control method found utility in cases with small aneurysms and relatively narrow-necked internal carotid artery. We observed no intraprocedural complications in this study. Conclusion This technique enabled secure coil deployment without navigating another microcatheter or balloon catheter around the aneurysms.