膠芽腫周辺の造影効果を伴わない拡散強調画像高信号域 : 診断と特異的予後因子としての所見

内容の要旨 , 審査の要旨広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

A Case of Foraminal Disc Herniation Successfully Treated via Paraspinal Transpars Approach

A 61-year-old man presented with an excruciating pain in the right lower extremity. The pain was aggravated by a short distance walk and lateral bending to the right. These symptoms implied right L4 radicular pain. Magnetic resonance images revealed foraminal disc herniation at the right L4-5 level. After failure of conservative treatment, the patient underwent surgery via the paraspinal transpars approach. Following exposure of the right lateral edge of the L4 lamina, we partially resected a part of the pars interarticularis in accordance with the preoperative simulation using a 3-dimensional printed bone model. Fragmented discs compressing the dorsal root ganglion of L4 nerve root were totally removed. Postoperative computed tomography showed complete preservation of the facet. The patient showed remarkable relief from the pain and returned to his job a week after the surgery. Foraminal disc herniations cause fierce leg pain and are often intractable to conservative treatment. Selection of the surgical approach is often a matter of debate. The paraspinal transpars approach was effective and a less invasive surgical method in that it can preserve the facet joint. A three-dimensional printed bone model was useful in determining the minimal resection range of the pars interarticularis

A Case of Holocord Leptomeningeal Dissemination from Cerebellar Hemangioblastoma without von Hippel-Lindau Disease

Hemangioblastoma disseminated along leptomeninges from the solitary cranial lesion without von Hippel-Lindau (VHL) disease is a quite rare instance with 23 cases reported in 40 years. We add a new case and discuss these rare instances. A 55-year-old female underwent surgery for total removal of cerebellar hemangioblastoma. Twenty months later, magnetic resonance (MR) images of the spinal cord revealed a tumor compressing the thoracic cord at T3-4 level which was removed en bloc by emergent spinal surgery. However, paraplegia and bowel bladder dysfunction recurred 5 months after the spinal surgery. Spine MR images showed diffuse enhancement of subarachnoid space. Exploratory surgery disclosed that the enhanced lesion was disseminated hemangioblastoma. After whole spinal irradiation, she was transferred to a palliative care hospital. Even after complete removal, possibility of leptomeningeal dissemination demands continuous follow-up. The mechanism of seeding of hemangioblastoma remains unclear, but attention must be paid to avoid spreading tumor cells during surgery because all the disseminated cases had precedent cranial surgery

A Case of Cutaneous Meningioma in the Rudimentary Meningocele

We report a rare case of neonatal cutaneous meningioma derived from a rudimentary meningocele. This neonate had a congenital skin-covered hump in the thoracolumbar region. Computed tomography showed bifid laminae of T12 and L1 underneath the mass lesion. Magnetic resonance images showed the mass to have no cerebrospinal fluid space and that it had a stalk connecting to the spinal canal. Split cord malformation was also observed under the bifid laminae. Because of the increasing size of the lump and cosmetic reasons, the parents opted for surgical treatment. We operated on the patient 9 months after birth. Operative findings showed that the cutaneous mass was connected to intraspinal contents by a vascular stalk and it was totally removed. The split spinal cord was untouched. The histopathological findings of the mass showed components of meningioma with a collagenous matrix. We concluded that this patient had a meningioma derived from rudimentary meningocele

Posterior Ring Apophysis Separation (PRAS) : A relatively rare clinical entity in adolescents & young adults

Herniated Lumbar Disc (HLD) may be associated with separation of the posterior ring apophysis of the adjacent vertebral body. It is often diffi cult to diagnose radiologically and may be confused with calcifi cation of the posterior vertebral structures. We report a 32 years old male, presenting with a history of low back pain radiating to the left lower limb and associated with tingling sensation and paresthesia. Magnetic Resonance Imaging (MRI) of lumbosacral (LS) spine revealed left L5-S1 lateral disc herniation compressing the exiting nerve root. CT scan with sagittal reconstruction of LS spine revealed PRAS of upper lip of S1 vertebra. L5 partial laminectomy and microdiscectomy with removal of the loose bony fragment was done. Post-operative MRI demonstrated decompression of the spinal canal and the neural foramen. We report this case to familiarize the clinicians with this clinical entity as it requires strong clinical suspicion coupled with sagittal reconstruction CT scan for diagnosis and extensive exposure with removal of loose fragments together with discectomy for adequate relief of the symptoms

Effect of bevacizumab against cystic components of brain tumors

Abstract Background Bevacizumab improves symptoms via reducing the peritumoral edema and/or normalizing blood brain barrier, and occasionally via reducing the tumor size. However, the effect against active cystic components has not been documented yet. Materials and Methods Between 2008 and 2018, 139 patients with primary or metastatic brain tumors were treated with bevacizumab (BEV) in our institution. The images and symptoms before and after administration of BEV were examined, and changes in size of cysts were evaluated as follows: CR (complete disappearance), PR (reduction by ≥50%), MR (reduction by ≥25%), SD (size change <25%), PD (increase by ≥25%). The effect of BEV on tumor itself was determined according to Response Assessment in Neuro‐Oncology criteria. Results Of the 139 patients, 21 (15.1%) had cystic components. The best responses of cysts to BEV treatment were as follows: CR 6, PR 7, MR 4, SD 4. The group of patients with progressively increasing cysts prior to BEV treatment had significant cyst size reduction compared to stable cyst size groups, at initial imaging after BEV (mean 62.6% vs 22.5%, P = .0055) and at best response timing (mean 76.3% vs 32.8%, P = .0050). Patients with cysts showed significant improvement in symptoms after the treatment with BEV compared to patients without cysts (P = .0033). However, response rate was not different between patients with or without cysts. Overall survival after starting BEV was not different between glioblastoma patients with or without cysts. Conclusion Bevacizumab is effective against progressively increasing cysts. Although cysts reduction effect and tumor response and/or overall survival are independent, BEV may be effective in patients who are symptomatic due to cyst enlargement