Stereotactic radiotherapy of radiation-induced meningioma previously irradiated retrobulbar for Graves' ophthalmopathy: A case report.

A 69-year-old woman was diagnosed with an asymptomatic intracranial tumor nine years ago and has been followed with annual MR imaging studies. Two years ago, the tumor had grown in size, requiring treatment. She experienced ophthalmopathy due to hyperthyroidism 27 years ago and was treated with 20 Gy in 10 fractions using parallel opposed beams to her bilateral posterior eyeballs, supplemented with steroid pulse therapy. The tumor originated in the medial aspect of the right sphenoid border and compressed the temporal lobe, while bone infiltration was observed, partially extending to the soft tissue outside the maxillary sinus. The tumor was removed by craniotomy. The pathological diagnosis was atypical meningioma (WHO grade II). Four months postsurgery, the resection cavity's tumor exhibited growth inclination, necessitating Gamma Knife radiosurgery. Radiation planning was executed at a marginal tumor dose of 30 Gy in 5 fractions. Since the optic nerve had been previously exposed to radiation, a plan was devised to minimize radiation exposure. The dose on the optic nerve was limited to 6.9 Gy in 5 fractions. She did not experience any visual or visual field disruptions postradiation. This is a case of radiation-induced meningioma resulting from radiation therapy for Graves' ophthalmopathy and is the first reported case of a grade II meningioma. The patient's condition calls for adjuvant radiation therapy following surgical removal. Accordingly, a radiation treatment plan that safeguards the optic nerve, which was previously exposed to radiation, was deemed indispensable.

Facial Nerve Neurolymphomatosis That Extends to Both the Brainstem and Extracranial Regions.

A 73-year-old female developed right facial paralysis of House-Brackmann (H-B) grade III and was diagnosed with Bell's palsy. After three months of steroid therapy, she developed progressive hearing loss, and an MRI revealed a tumor in the right internal auditory canal. Within a few months, the right facial nerve palsy recurred, and the patient was treated with Gamma Knife radiosurgery. The tumor in the irradiated region disappeared, but new dysphagia was observed, and a right parotid gland tumor was detected for the first time. Tumors of the right parotid gland and the digastric muscle of the jaw were surgically resected, and a diagnosis of diffuse large B-cell lymphoma was made. The tumor had invaded the cranial nerves and brainstem region, and the patient did not wish to undergo further medical therapy. This was a case of malignant lymphoma that started as facial paralysis and invaded the brainstem, and testing for possible lymphoma at an early stage prior to radiotherapy was desirable.

Long-term recurrence after surgery for schwannoma of the cauda equina.

Background: Cauda equina tumors are rare primary spinal tumors. Histologically, the most common tumor arising from the cauda equina is a schwannoma. However, little is known about the long-term postoperative outcomes of cauda equina schwannoma. Here, we reviewed the median-to-long-term postoperative outcomes of eight of our own patients with schwannomas of the cauda equina. Methods: Between 2007 and 2020, we, retrospectively, reviewed eight patients with cauda equina schwannomas (CESs) undergoing nine operations at our institution. There were five males and three females averaging 56.5 years of age who were followed for over 40 postoperative months. The study included assessment of the following variables: the modified McCormick scale, tumor size, location, extent of resection, treatment of the tumor involving nerve roots, and postoperative observational follow-up. Results: Gross-total resection was achieved in all eight patients; none received adjuvant therapy. The involved nerve roots were completely sacrificed in seven patients and partially resected in one. During a median follow-up of 108 months, only one patient sustained a tumor recurrence 164 months following the index surgery. Conclusion: CESs may recur more than 10 years after the original surgery. Radical resection of the tumor, including complete removal of the involved nerve root during the index surgery, and long-term postoperative follow-up is, therefore, essential.

Gamma knife radiosurgery cured hydrocephalus in non-hemorrhagic brain stem arteriovenous malformation.

A 13-year-old boy, with a history of intermittent headache and transient diplopia, was found to have non-hemorrhagic cerebral arteriovenous malformation in the midbrain tegmental region associated with hydrocephalus. Gamma knife radiosurgery was performed at 16 Gy with 75% marginal dose. Posttreatment course was uneventful. Follow-up MR imaging at one year after the treatment revealed complete disappearance of the abnormal vascular flow voids. The size of each ventricle at the treatment and at one year after treatment were as follows; 60.2 cc and 20.9 cc in the lateral ventricles, 3.7 cc and 2.7 cc in the third ventricle. The hydrocephalus might be caused by obstructive mechanism but mostly by high venous pressure due to the shunt blood flow. The goal of treatment for hydrocephalus should be nidus obstruction and normalizing the vascular flow.

Lumbar Canal Stenosis Caused by Spondylolisthesis and Intraspinal Canal Calcifications Associated with Psoriatic Arthritis: A Case Report.

Soft tissue calcifications are common findings in patients with various diseases, such as malignant tumors, collagen diseases, trauma, and chronic kidney disease. The majority of these lesions are not clinically significant; however, they can cause specific disorders within a limited space, such as the spinal canal. Here, we report the case of a patient undergoing fusion surgery for lumbar canal stenosis due to degenerative spondylolisthesis and multiple intraspinal canal calcifications associated with psoriatic arthritis (PsA). A 55-year-old female patient presented with pain in the left leg and intermittent claudication for 1 month. One year ago, she was diagnosed with PsA and received outpatient treatment, including biological medication, at the Division of Rheumatology, Department of Internal Medicine of our institution. She was referred to our department, and radiological examination revealed lumbar canal stenosis caused by spondylolisthesis and multiple calcifications in the lumbar spinal canal. We performed posterior lumbar interbody fusion (PLIF) with percutaneous pedicle screw fixation concomitant with removal of the calcifications. The postoperative course was uneventful, and her neurological symptoms improved. Although several prior case reports have noted intraspinal canal calcifications due to collagen disease or chronic kidney disease, calcifications associated with PsA are rare. We discuss the diagnosis of PsA and its relationship with intraspinal canal calcifications by reviewing the previous relevant literature.

[Posterior Approach for Cervical Spondylotic Myelopathy in Patients Older than 80 Years of Age].

OBJECTIVE: We aimed to investigate the characteristics and operative results of elderly patients with cervical spondylotic myelopathy(aged ≧80 years)treated using the posterior approach. METHODS: Between April 2010 and December 2018, 21 patients aged ≧80 years(older group:8 men and 13 women;age range, 80-90 years)who underwent laminoplasty were reviewed and compared with 23 patients aged <80 years(younger group;13 men and 10 women;age range, 42-79 years)who underwent laminoplasty. The following data were obtained from chart reviews:age;sex;cervical canal stenosis level;time to operation;symptoms(e.g., gait disturbance);comorbidities(hypertension, diabetes mellitus, cancer, heart disease, ischemic cerebrovascular disease, and lumbar canal stenosis);antithrombotic drug use;cardiac, pulmonary, and renal functions;operative time;volume of blood loss during the operation;postoperative delirium;and follow-up period. Neurological deficits before and after the surgery were assessed using the neurosurgical cervical spine scale(NCSS). Data were statistically analyzed, and p-values <0.05 were considered statistically significant. RESULTS: The operative time, symptoms(hypertension), renal function, and preoperative NCSS score were significantly different between the older and younger groups. Meanwhile, most variables showed no significant differences between the groups. Although the preoperative NCSS score was lower in the older group, there was no significant difference in the degree of improvement in the NCSS score after surgery. CONCLUSIONS: The findings of this study suggest that we should not hesitate to perform surgery for cervical spondylotic myelopathy in elderly patients with favorable cardiorespiratory function.

[Surgical Results of Lumbar Degenerative Disease with Foot Drop].

Drop foot is associated with various diseases, such as peripheral nerve disease, lumbar degenerative disease, metabolic disease, and endocrine disease. Among lumbar degenerative diseases, lumbar disc herniation and lumbar canal stenosis are most commonly reported. We report the surgical outcomes of patients with drop foot caused by lumbar degenerative diseases. Between 2008 and 2018, we encountered 24 cases of drop foot in patients who underwent surgery of the lumbar lesion. The mean age was 69.5 years(49-88 years). Fourteen patients were male and ten were female. The mean time interval between the onset of drop foot and surgery was 51.5 days(from 7 days to 1 year). Drop foot, as a clinically significant muscle weakness, was defined at levels of manual muscle test(MMT)3 or lower. Responsible lesions for drop foot were canal stenosis at L4/5 in 8 cases, disc herniation at L4/5 in 10 cases, disc herniation at L5/S1 in 5 cases, and far-out syndrome in 1. One case involved drop foot bilaterally. Muscle weakness improved by surgery at levels of MMT 4 or greater in 16 cases(66.7%). Six cases of complete paresis or tibialis anterior muscle atrophy preoperatively resulted in no improvement;however, neuralgia was relieved in all. Twelve of 15 cases(80%)of lumbar disc herniation and 4 of 10 cases(40%)of lumbar canal stenosis resulted in improvement. Between disc herniation and canal stenosis, the surgical success rate was not statistically different. Age and the time interval between the onset and surgery were also not significant factors of the outcome. Surgical intervention seems to be beneficial even in cases of severe muscle weakness since pain relief can be expected, which leads to improvement in gait.

[Pseudoaneurysm of Neck External Carotid Artery Related to Chiropractic Manipulation].

A 55-year-old man presented with progressive pain and expanding swelling in his right neck. He had no history of trauma or infectious disease. The patient had undergone chiropractic manipulations once in a month and the last manipulation was done one day before the admission to our hospital. On examination by laryngeal endoscopy, a swelling was found on the posterior wall of the pharynx on the right side. The right piriform fossa was invisible. CT revealed hematoma in the posterior wall of the right oropharynx compressing the airway tract. Aneurysm-like enhanced lesion was also seen near the right common carotid artery. Ultrasound imaging revealed a fistula of approximately 1.2 mm at the posterior wall of the external carotid artery and inflow image of blood to the aneurysm of a diameter of approximately 12 mm. No dissection or stenosis of the artery was found. Jet inflow of blood into the aneurysm was confirmed by angiography. T1-weighted MR imaging revealed presence of hematoma on the posterior wall of the pharynx and the aneurysm was recognized by gadolinium-enhancement. We performed emergency surgery to remove the aneurysm while preserving the patency of the external carotid artery. The pin-hole fistula was sutured and the wall of the aneurysm was removed. Histopathological assessment of the rissue revealed pseudoaneurysm. The patient was discharged after 12 days without deficit. Progressively growing aneurysm of the external carotid artery is caused by various factors and early intervention is recommended. Although, currently, intravascular surgery is commonly indicated, direct surgery is also feasible and has advantages with regard to pathological diagnosis and complete repair of the parent artery.

[Implementation of Penumbra-assisted Half-Stent Thrombectomy for Patients with Acute M2 Occlusion:Results of Initial Experiences].

The benefits of mechanical thrombectomy(MT)for acute M2 occlusion have remained unclear because of unavoidable device-related complications due to vascular morphological characteristics. We developed a Penumbra-assisted half-stent thrombectomy for achieving secure retrieval of thrombus with minimal damage to the small-caliber vessel. In total, 6 patients were treated with MT for acute M2 occlusion using this technique between November 2016 and May 2017, including 3 men and 3 women, mean age 74.8(51-98)years. The mean baseline National Institutes of Health Stroke Scale score was 17.5(6-32), and Alberta Stroke Program Early Computed Tomography Score-Diffusion-Weighted Imaging was 7.5(6-9). After navigation of the microcatheter through the thrombus in M2 supported by a Penumbra 4MAX as a distal access catheter, the stent retriever(SR)was partially deployed to cover the entire thrombus. The 4MAX was then advanced towards the caudal end of the thrombus, and the SR was pulled back into the 4MAX with simultaneous aspiration of the 4MAX. We used the Trevo XP3 in 5 patients and Revive SE in 1 patient. The mean procedure time from groin puncture to recanalization was 60(54-66)min. Successful recanalization(Thrombolysis in Cerebral Infarction score 2b or 3)was achieved in 5(83%)patients. There were no cases of symptomatic intracranial hemorrhage. Good outcome(modified Rankin Scale score 0 to 2)at 3 months was achieved in 3(50%)patients. Penumbra-assisted half-stent thrombectomy appears to be an effective alternative strategy in MT for acute M2 occlusion.

[Two Cases of Bilateral Orbital Metastases of Breast Cancer].

Two cases of breast cancer with bilateral orbital metastases associated with intracranial metastases are presented. Case 1:A 61-year-old woman who was diagnosed with breast cancer 14 years earlier presented with rapid deterioration of visual acuity, eye pain, and limitation of left-sided extraocular motility. Magnetic resonance(MR)images showed an enhanced lesion in the left orbital apex, ethmoid sinus, and right middle fossa. The first gamma knife radiotherapy(35 Gy, 5 Fr)was performed successfully, but was followed by recurrence 18 months later in the right intraorbital, where newly formed iso-intensity masses in the extraconal compartment were found. The second gamma knife radiosurgery was performed for three masses(20 Gy). Case 2:A 35-year-old woman with breast cancer who was diagnosed 22 months earlier was treated for meningeal carcinomatosis by whole-brain radiation(30 Gy, 10 Fr)and intrathecal chemotherapy. Eight months later, swelling in both eyelids and limitation of extraocular motility developed rapidly. MR imaging revealed an infiltrating lesion in the cone with heterogenous signal that was encasing, but not infiltrating the optic nerves. The extraconal lesion extended into the soft tissue of the lower eye lid. She expired one week after diagnosis. With the increasing number of long-term survivors with breast cancer, intraorbital metastases may be found during the course of treatment for intracranial lesions. Understanding the unique clinical presentation and characteristic MR findings of this rare entity are emphasized.

Myoarchitectonic spinolaminoplasty: efficacy in reconstituting the cervical musculature and preserving biomechanical function.

OBJECT: Laminoplasty has been used to expand the cervical spinal canal, based on the belief that reconstruction of the laminae preserves musculoskeletal function. The true efficacy of laminoplasty for maintaining spinal alignment, stability, and flexibility, however, remains to be proven. The authors have developed a new method, myoarchitectonic spinolaminoplasty (MSLP), which preserves all of the nuchal muscles and reconstitutes all of the musculoskeletal couplings to the posterior elements of the vertebrae. The details of this technique are described, and the efficacy of the technique in conserving muscle volume, alignment, and motion, as well as in preventing postoperative musculoskeletal discomfort, is assessed. METHODS: The authors' previous midline-splitting laminoplasty procedure, which utilized a hydroxyapatite (HA) implant as a substitute for the spinous process, was improved. Detachment of the muscles is avoided with this new technique by cutting inside the spinous process. The bone-muscle flaps are affixed to the HA spinous process. Radiographs, computed tomography scans, and neurological evaluations obtained at the 1-year follow-up in the groups of consecutive patients assessed immediately prior to and after the modification of the previous technique (the control and the MSLP groups, respectively) were analyzed and compared. RESULTS: The HA bone constructs became integrated due to osteoconduction. The cross-sectional area of the semispinalis capitis, semispinalis cervicis, and multifidus muscles remained significantly larger in the MSLP group. Slight attenuation in lordosis was observed in the control group, but was prevented in the MSLP group. Range of motion was somewhat restricted in the MSLP group, but the incidence of neck pain and shoulder strain was significantly reduced. CONCLUSIONS: The new MSLP method was effective in preserving the volume and functions of the nuchal musculature and helping to minimize postoperative musculoskeletal complaints.

Cadaveric and clinical study of endoscope-assisted microneurosurgery for cerebral aneurysms using angle-type rigid endoscope.

Highly advanced optical equipment enables endoscopic surgery to be performed in neurosurgery. We developed an angle-type rigid endoscope having an angled shaft, and has performed endoscope-assisted surgery in neck clipping of 50 cerebral aneurysms. Anatomical study concerning the perforating branch was made through a pterional approach using 3 cadavers. By using endoscope, we can observe the posterior communicating artery and anterior choroidal artery behind the internal carotid artery without retract the internal carotid artery and the surrounding structures. Furthermore IIIrd~VIIIth cranial nerve in opposite side and basilar artery in the posterior fossa can be observed. As the clinical study, we used endoscope in 50 clipping of cerebral aneurysms (29 Internal carotid artery aneurysms, 6 anterior communicating artery aneurysms, 2 anterior cerebral artery aneurysms, 7 middle cerebral artery aneurysms, 5 vertebral artery-posterior inferior cerebellar artery aneurysm, and basilar bifurcation aneurysms). The endoscopic image showed in incomplete clipping in 2 cases, where additional clipping was then performed. In all subject, complete clipping was performed using both microscopic and endoscopic view. Use of the angle-type rigid endoscope together with Doppler ultrasound, should increase the feasibility of complete clipping procedure, resulting in reduced complication rate.