To describe the detailed microsurgical anatomy of the clinoid(C5)segment of the internal carotid artery(ICA) and surrounding structures and clarify the anatomical relationships of this region emphasizing their clinical relevance, authors examined in 70 specimens from 35 formalin fixed cadaveric heads. Removal of the anterior clinoid process exposes the C5 segment of the ICA which is encircled by the thin inner dural layer of the cavernous sinus wall. Opening this membrane enables entrance into a narrow space that communicates with cavernous sinus through the proximal dural ring. Unlike the dura of the distal dural ring that is tightly attached to the ICA, the proximal dural ring is always incompetent. The C5 segment of the ICA has been considered by the majority of authors to be extracavernous. This understanding developed because most investigators overlooked the thin inner dural layer encircling the clinoid ICA. The narrow space between the inner dural layer and the ICA communicates with cavernous sinus through an incompetent proximal dural ring. Therefore, the clinoid ICA should be considered to be the most rostral portion of the cavernous (C4)segment of the ICA. The proximal dural ring is a surgical landmark rather than a true dural ring.
Cadaver ; Carotid Artery, Internal* ; Cavernous Sinus ; Formaldehyde ; Head ; Humans ; Membranes ; Research Personnel

OBJECTIVE: Various lesions including tumors occupying in the presellar and suprasellar regions have been traditionally removed by the transcranial approach. The new modified transsphenoidal approaches(TSAs) have been proposed to avoid the craniotomy and to get better surgical view. MATERIALS AND PATIENTS: The sellar floor and presellar anterior cranial fossa were removed through the sublabial transseptal transsphenoidal technique in the "transsphenoidal supradiaphragmatic intradural approach". One tuberculum sella meningioma and a suprasellar Rathke's cleft cyst confined to the pituitary stalk were removed via this approach. RESULTS: The dissection of the anterior intercavernous sinus, diaphragma sella, and arachnoid membrane allowed a wide surgical field of pre- and suprasellar areas and facilitated a safe removal of lesions without significant surgical complications in our cases. CONCLUSION: From the authors' limited experience, the advantages of this technique are as follows: 1) it can be easily applicable through a minor modification of the standard TSA, 2) excellent anatomical exposure of the structures located in the supradiaphragmatic suprasellar cistern, and 3) might be suitable to remove small lesions located in the presellar and adjacent to the pituitary stalk region.
Arachnoid ; Cranial Fossa, Anterior ; Craniotomy ; Humans ; Membranes ; Meningioma ; Pituitary Gland

case of occult intrasacral meningocele associated with arachnoid cyst in a 35-year-male is reported. The patient presented with a history of severe sacrococcygeal pain, constipation, and urinary incontinence for several months. Myelography revealed delayed filling of a meningocele. Computed tomographic(CT) myelography and magnetic resonance(MR) imaging showed huge intrasacral mass without neural elements. A favorable outcome was achieved by decompression of the cyst, obliteration of the conduit to subarachnoid space, and fenestration of arachnoid cyst into subarachnoid space.
Arachnoid* ; Constipation ; Decompression ; Humans ; Meningocele* ; Myelography ; Sacrum ; Subarachnoid Space ; Urinary Incontinence

The authors report a case of far lateral disc herniation at L4-5 found one year after percutaneous laser lumbar discectomy. The patient was found to be suffering from new-onset right lumbar radiculopathy 6 months after his first operation, and post operative lumbar MRI confirmed a far lateral extraforaminal disc herniation at L4-5, with compression of the nerve. This corresponded to the nucleotomy site of the probe. The patient underwent surgery employng the combined paraspinal intertransverse and interlaminar approach, and his symptoms were relieved. This case emphasizes the importance of removing nuclear material, and shows that remaining material can herniate through a percutaneous discectomy window.
Diskectomy* ; Diskectomy, Percutaneous ; Humans ; Magnetic Resonance Imaging ; Radiculopathy

The authors report a case of rostral mesencephalic dysfunction due to obstructive hydrocephalus secondary to periaqueductal tumor who suffered multiple shunt failures and shunt revision. This patient presented with clinical syndromes, including akinetic mutism and diencephalic autonomic epilepsy. He had computed tomography(CT) and magnetic resonance(MR) findings of dilatation of ventricular system with periaqueductal tumor. The anatomical substrates of clinical findings are reviewed. A discussion of the probable mechanism proposes that dilatation of 3rd ventricle and rostral aqueduct sufficiently explains the entire syndrome.
Akinetic Mutism ; Dilatation ; Epilepsy ; Humans ; Hydrocephalus* ; Mesencephalon*

The authors describe a case with an uneventful outcome following prolonged temporary arterial occlusion during surgery for an aneurysm of the dorsal internal carotid artery(ICA). It has been shown that in various situations arising during aneurysm surgery, temporary arterial occlusion effectively prevents a premature rupture. It is not possible, however, to predict beforehand what the permissible occlusion time for any individual patient might be. During dissection of a blister aneurysm of the ICA, premature rupture developed, and intermittent temporary occlusion of the ICA, which lasted for about 150 minutes, was then undertaken. In addition, intraoperative neuroprotection was effected in several ways, including intermittent reperfusion and the administration of mannitol, thiopental sodium and steroid. There were no significant postoperative neurological deficits. To the authors' knowledge, this report is unusual in that it documents prolonged temporary occlusion without major neurological sequelae in intracranial aneurysm surgery. Permissible temporary occlusion time and neuroprotective methods are also discussed.
Aneurysm* ; Blister ; Carotid Artery, Internal* ; Humans ; Intracranial Aneurysm ; Mannitol ; Reperfusion ; Rupture ; Thiopental

Glomus jugulare tumors are usually slow growing, but highly vascularized tumor. The authors report the case of huge glomus jugulare tumor treated by surgical resection with preoperative embolization. A 32-year old male patient presented with a history of right-sided facial palsy and hearing disturbance. Magnetic resonance imaging demonstrated an irregular large mass with multiple signal voids in the right temporal area. Prior to surgical excision of tumor, the patient underwent superselective embolization. Embolization of the tumor and its dominant feeding arteries were achieved. Six days later, the patient underwent an infratemporal fossa approach to remove the tumor. The patient did well postoperatively except CSF leakage that was treated successfully by dura repair. We discuss the usefulness of preoperative embolization and infratemporal approach for the huge glomus jugulare tumor.
Adult ; Arteries ; Facial Paralysis ; Glomus Jugulare Tumor* ; Glomus Jugulare* ; Hearing ; Humans ; Magnetic Resonance Imaging ; Male

A new technique of endoscope assisted anterior cervical foraminotomy was developed to improve the conventional microsurgical anterior cervical foraminotomy. Microsurgical anterior cervical foraminotomy provides direct anatomical decompression of the compressed nerve root by removing the spondylotic spur or disc fragment while preserving the functioning segment of the disc. The authors modified the anterior cervical foraminotomy using the MED TM(Microendoscopic discectomy) system to minimize the skin incision, and to achieve safe drilling and easy retraction. The uncinate process was drilled under endoscopic visualization through a tubular retractor. This technique has been applied to 13 patients with single level radiculopathy due to posterolateral osteophyte or soft disc herniation. The nerve roots were decompressed successfully under endoscopic control as in conventional microsurgical foraminotomy through a 2cm skin incision. Postoperatively, all patients showed improvements in their radiculopathic symptomatologies. Corresponding CT scans confirmed satisfactory anatomical decompression in all patients. This surgical technique has shown good clinical outcomes with fast recovery.
Decompression ; Endoscopes* ; Foraminotomy* ; Humans ; Osteophyte ; Radiculopathy ; Skin ; Tomography, X-Ray Computed

The authors analysed 140 cases of subdural hygroma developed after head injury and various neurosurgical operations and was treated at Hanyang university hospital from 1983 to 1989. The results were analysed and summarized as follows. 1) The peak incidence was the age over 50 and under 10. 2) 104 cases(74.4%) were bilateral frontotemporoparietal lesions. 3) Causes were head injury(121 cases), operation for intracranial aneurysms(5 cases), ventriculoperitoneal shunt(5 cases), traumatic(2 cases), external ventricular drainage(1 case). 4) Change in mental status without focal sign of brain damage was presenting symptom. 5) Operation was underwent if 63 cases and the reaccumulation rate was high (26.8%) after trephination but outcome was favorable. 6) Mortality rate in traumatic subdural hygroma was low(5.8%) because brain CT could detect subdural hygroma easily in early stage.
Brain ; Craniocerebral Trauma ; Head ; Incidence ; Mortality ; Subdural Effusion* ; Trephining

Fibrous dysplasia is a benign disorder of bone primarily affecting young people from childhood through the third decade. It usually manifests as an enlargement of bones in and about the orbits or the the cranial vault. Whether localized or diffuse, it rarely involves the cervical spine. We report a case of fibrous dysplasia involving axis combined with atlantoaxial instability which was caused by odontoid process fracture. Transfacetal screw fixation augmented with Halifax interlaminar clamp technique was applied to obtain atlantoaxial stability. Postoperative course was unevenful and postoperative radiologic findings revealed favorable fixation of atlantoaxial joint. The pertinent literature on fibrous dysplasia and atlantoaxial instability is reviewed and discussed.
Atlanto-Axial Joint ; Axis, Cervical Vertebra ; Odontoid Process ; Orbit ; Spine*