Landmarks for the transverse sinus and torcular herophili.
Explore the source record for details and available documents.
Aged↗
Biomedical subjects
I M Ziyal
Publications and source records attributed to I M Ziyal.
Transtentorial approach to the posterior temporomedial structures.
The supracerebellar transtentorial (SCTT) approach, a modification of the infratentorial supracerebellar approach, facilitates simple and minimally invasive access to posterior temporomedial structures without requiring retraction of the temporal or occipital lobe. The SCTT approach was used in 16 patients over a 3-year period. Eleven patients harbored tumors confined to, or located mainly within, the posterior hippocampal formation, three patients harbored aneurysms (one ruptured posterior cerebral artery [PCA] aneurysm at the P2-P3 junction, one ruptured giant PCA [P2] aneurysm, and one giant basilar artery-superior cerebellar artery aneurysm), one patient had juvenile-type moyamoya disease, and one patient suffered from medically intractable epilepsy. In these patients, the SC
Hippocampus↗
Calvarial metastasis of a paraganglioma. Case report and review of the literature.
BACKGROUND: Metastasis of a paraganglioma (PRG) to the calvarium is very rare. In this paper, the case of a 25-year-old male with metastasis of a PRG to the frontoparietal bone is described. CASE DESCRIPTION: The patient presented with bulging on the left side of the head, headache, and weight loss. Magnetic resonance imaging (MRI) revealed a mass lesion in the left frontoparietal region that had destroyed both the external and internal table of the bone, extending under the skin and above the dura mater. After a frontoparietal craniotomy the tumor was removed totally. Histopathological examination revealed the "Zellballen," which are pathognomonic for a PRG. Systemic examination and radiological investigation revealed no primary tumor source. CONCLUSION: Metastasis of a PRG to the calvarium is possible; radical removal of the tumor will provide a cure.
Adult↗
Extradural posterior inferior cerebellar artery.
Explore the source record for details and available documents.
Arteries↗
Vertebral artery to common carotid artery bypass in Takayasu's disease with delayed cerebral ischemia.
UNLABELLED: Takayasu's Arteritis is a progressive occlusive disease of the aortic arch and its branches. It may need several bypass procedures along with or without endovascular techniques. CASE DESCRIPTIONS: A twenty-six year old woman who had a history of Takayasu's Arteritis, and had a Gore-Tex Dacron Y-graft from the ascending aorta to the right subclavian and right common carotid arteries 18 years before, is presented. She presented with recurrent hemispheric ischemia and transient ischemic attacks and severe long segment stenosis in the left common carotid artery. She was successfully treated with a saphenous vein graft bypass from the left vertebral artery to the common carotid artery. The stenosis of the brachiocephalic graft was successfully treated by angioplasty. Three months follow up showed stenosis of the left VA immediately proximal to the proximal anastomosis which was managed successfully with angioplasty. CONCLUSIONS: The surgical treatment of Takayasu's Arteritis with bypass procedures needs a complex overview and follow up. A regular follow up is mandatory for evaluation and planning of appropriate management, in view of the progressive nature of the disease process.
Adult↗
Surgical management of cavernous malformations of the brain stem.
Different surgical approaches to the brain stem with results of excision of brain stem cavernous malformations are reported. Nine patients with brain stem cavernous malformations were operated with six different approaches. The patients were evaluated neurologically, and by magnetic resonance imaging (MRI) examination. All patients had at least one and often more episodes of haemorrhage. Seven patients underwent the total removal of the malformation, without recurrence. One patient with a large medullary cavernoma had recurrence, but without further growth. One patient with a large pontomesencephalic malformation and partial resection, suffered rebleeding due to residual cavernoma. The mean follow-up period was 49 months (range 3-112). The results of surgery were excellent or good in eight patients, and poor (worsening) in one. It is concluded that surgical resection is recommended for the cavernous malformations of the brain stem which are symptomatic, have bled or are growing, and are approachable through one of the pial surfaces of the brain stem. Different skull base approaches are useful for this procedure. Radiosurgery is not recommended in such cases.
Adult↗
Subtonsillar-transcerebellomedullary approach to lesions involving the fourth ventricle, the cerebellomedullary fissure and the lateral brainstem.
We describe the use of the subtonsillar-transcerebellomedullary approach to laterally placed fourth ventricle and brain-stem lesions. The subtonsillar-transcerebellomedullary approach to the fourth ventricle and the lateral brainstem was used in six patients: three patients with tumours of the fourth ventricle and brainstem (two ependymomas and one papillary thyroid carcinoma metastasis), two patients with cavernous angiomas of the brainstem and one patient with a distal posterior inferior cerebellar artery (PICA) aneurysm. The microsurgical anatomy of this approach was studied in five cadaveric head specimens. The tumours and cavernous angiomas were removed and the distal PICA aneurysm was clipped successfully. In all patients the Karnofsky performance scale (KPS) was equal to or better than the preoperative status on follow-up examinations. The anatomical studies also revealed the extensive exposure provided with this approach. The subtonsillar-transcerebellomedullary approach is recommended for lesions occupying the cerebellomedullary fissure, and the lateral aspect of the fourth ventricle.
Brain Stem↗
Cerebral metastasis of a uterine leiomyosarcoma--case report.
A 38-year-old female presented with sudden neurological deterioration 6 years after an operation and chemotherapy for uterine leiomyosarcoma. An extremely rare metastasis of the uterine leiomyosarcoma to the brain was identified and totally resected. Whole brain irradiation (50 Gy) was given. A recurrence of the metastasis was resected 10 weeks later. She ultimately died of a second recurrence. Aggressive surgical management of cerebral metastasis of uterine leiomyosarcoma may achieve an improved outcome.
Adult↗
Bilateral vertebral artery occlusion following cervical spine trauma--case report.
A 41-year-old female presented with a rare case of bilateral vertebral artery occlusion following C5-6 cervical spine subluxation after a fall of 30 feet. Digital subtraction angiography showed occlusion of the bilateral vertebral arteries. Unlocking of the facet joint, posterior wiring with iliac crest grafting, and anterior fusion were performed. The patient died on the 3rd day after the operation. This type of injury has a grim prognosis with less than a third of the patients achieving a good outcome.
Adult↗
Migration of the abdominal catheter of a ventriculoperitoneal shunt into the scrotum--case report.
A 3-day-old male neonate presented with migration of the ventriculoperitoneal (VP) shunt tip through the patent processus vaginalis resulting in scrotal hydrocele. The association of myelomeningocele with hydrocephalus may have been a predisposing factor in this rare complication. Development of scrotal swelling or hydrocele in a child with VP shunt should be recognized as a possible shunt complication.
Catheters, Indwelling↗
Variations of the extreme-lateral craniocervical approach: anatomical study and clinical analysis of 69 patients.
OBJECT: The aim of this study was to describe six variations of the extreme-lateral craniocervical approach, their application, and treatment results. METHODS: During a 4-year period 69 patients underwent surgery in which six variations of the extreme-lateral craniocervical approach were performed. The variations included: the transfacetal approach (TFA), performed to treat four lesions in the upper cervical spine anterior or anterolateral to the spinal cord; the retrocondylar approach, to treat five intradural lesions located anterolateral to the medulla oblongata and six vascular lesions to expose the extradural segment of the vertebral artery (VA); the partial transcondylar approach (PTCA), to treat 18 intradural lesions located anterior to the medulla oblongata; the complete transcondylar approach (CTCA), to treat 13 extradural lesions that involved the lower clivus and anterior upper cervical spine; the extreme-lateral transjugular approach, to treat 14 jugular foramen tumors; and the transtubercular approach with or without division of the sigmoid sinus, to treat complex VA and vertebrobasilar junction aneurysms. An anatomical prosection was performed to study the surgical exposure of each of the six variations of the extreme-lateral craniocervical approach. Total removal was achieved in 35 (69%) of the patients with tumor; subtotal resection was achieved in 16 (31%) of those patients. In the 12 patients with VA aneurysms, seven underwent clipping, three underwent trapping and a vein graft bypass procedure, and two underwent trapping without the use of a bypass procedure. In five other patients, different cystic, inflammatory, and other vascular lesions were successfully treated. Fifty percent of the patients who underwent surgery via the TFA, 83% via the of the CTCA, and 11% via the PTCA required an occipitocervical fusion procedure. The mean Karnofsky Performance Scale score was 74.7 preoperatively and 76.4 postoperatively. Major complications were hydrocephalus (nine patients), cerebrospinal fluid leakage (seven patients), worsened cranial nerve function (seven patients), vertebrobasilar vasospasm (one patient), and sigmoid sinus thrombosis (one patient). CONCLUSIONS: To treat lesions in the region of the foramen magnum and surrounding areas, the approach should be tailored to each specific lesion to provide the needed exposure without unnecessary operative steps.
Adult↗
The petrolingual ligament: the anatomy and surgical exposure of the posterolateral landmark of the cavernous sinus.
The petrolingual ligament is the posteroinferior attachment of the lateral wall of the cavernous sinus, where the internal carotid artery enters the cavernous sinus. The petrous segment of the internal carotid artery finishes and the cavernous segment begins at the superior margin of this ligament. The ligament is surgically important due to its identification as a landmark for dissection of the internal carotid artery during the approaches to posterolateral intracavernous and extracavernous lesions. It can be well exposed after mobilization of the gasserian ganglion, or after the trigeminal root and ganglion have been split along the junction of V2 and V3 (the transtrigeminal approach). The petrolingual ligament was studied in five cadaveric head specimens from ten sides. The size of the ligament was measured, and its anatomical, clinical and surgical importance is discussed.
Carotid Artery, Internal↗
The natural history of late diagnosed or untreated growing skull fractures: report on two cases.
Growing skull fractures (GSF) are rare complications of head trauma. Cases after childhood are extremely rare and demonstrate complicated pathological conditions which necessitate extensive treatment. We report on two rare cases of intracranial cysts related to growing skull fractures which are secondary to trauma sustained during childhood, and have been discovered in adolescence.
Adolescent↗
Extradural origin of the posteroinferior cerebellar artery: an anatomic study with histological and radiographic correlation.
OBJECTIVE: The posteroinferior cerebellar artery (PICA) usually arises from the intradural segment of the vertebral artery (VA). The extradural origin of the PICA is infrequent. Its preoperatory identification is important in surgical strategy during the exposure of the VA. METHODS: During an anatomic prosection, the VA was exposed at the craniocervical junction in cadaveric adult specimens. The extradural origin of the PICA was encountered bilaterally in one specimen and on one side in a second specimen. An anatomic study with histological and radiographic correlation was performed. RESULTS: Perforating branches originate from the PICA. They supply the middle and inferior third of the olive and the lateral aspect of the medulla. The PICA has cortical branches that lead to the cerebellum. Injury to the PICA can produce an infarction of these neural structures that can be asymptomatic or cause major neurological deficits. Radiographic results obtained using a lateral projection provided the most reliable delineation of the extradural origin of the PICA. When this artery originates at, or posterior to, the posterior aspect of the occipital condyle, an extradural origin is likely. CONCLUSION: Bilateral selective vertebral angiography should be performed with special attention to the relationships of PICA origins before any surgical exposure of the VA at the craniocervical junction, unless magnetic resonance angiography provides this information without question. A thorough understanding of the relative dominance of the VAs and PICAs, the location of the PICA origin, and the collateral circulation of the posterior fossa are prerequisites to surgery in this region. The preoperative identification of an extradural PICA is important in planning surgical strategy and in avoiding complications during operations near the foramen magnum.
Aged↗
Persistent trigeminal artery: an anatomic study.
INTRODUCTION: The most frequent embryonic communication between the vertebrobasilar and carotid systems is a persistent trigeminal artery (PTA). It has been observed in 0.1 to 0.2% of cerebral angiograms. We found this variation in an anatomic specimen, and after microscopic dissection, we performed an analysis of the course of the PTA and its relationship with the abducens nerve and the meningohypophyseal trunk. METHOD: A PTA was incidentally encountered in an injected cadaver specimen during a transpetrosal approach. This embryonic variation and its anatomic relationship are discussed. RESULTS: The PTA can take either a lateral or medial course regarding its relationship with the abducens nerve. When the PTA originates from the posterolateral aspect of the posterior bend of the cavernous carotid artery (C4 segment), it crosses underneath and distorts the abducens nerve, continuing between the abducens and trigeminal nerves. When taking a medial course, the PTA arises from the posteromedial aspect of the posterior bend of the cavernous carotid at the same segment and pierces the clival dura at the dorsum sellae. Cranial nerve displacement or distortion is less likely in this variation. In an analysis of carefully described anatomic studies, the PTA and meningohypophyseal trunk were found arising from either common or separated origins. CONCLUSION: The most frequent embryological anastomosis between the carotid and vertebrobasilar system is the PTA. Its course and relationship with the cranial nerves may determine its clinical presentation.
Aged↗
Anatomy of the frontotemporal branch of the facial nerve and indications for interfascial dissection.
INTRODUCTION: Many studies have been conducted of the surgical anatomy of the frontotemporal branch of the facial nerve (FTBFN). However, very few have addressed the indications for interfascial dissection. When the zygomatic arch needs to be exposed, the interfascial approach is recommended to protect the FTBFN. With the transbasal or subfrontal approaches, however, when a bicoronal skin incision is used, the need for the interfascial approach is not clear. METHODS: We studied 10 temporal regions (5 cadaveric heads). We dissected the recognized fascial layers of the temporal region and the FTBFN. We performed a histological study in a sixth specimen. RESULTS: We observed the following. 1) The galea and the superficial layer of the deep temporal fascia become fused in a curved line from the lateral orbital border 2.8 cm above the zygomatic arch to a point 3 cm posterior to the inferolateral angle of the orbit. 2) After this transitional area of adherence, the subgaleal loose cellular layer is lost and is replaced by a fibrofatty tissue. 3) The FTBFN in its course above the zygomatic arch runs in this tissue layer without being protected by the galea. 4) Over the superolateral angle of the orbital rim, the galea protects FTBFN, and there are no subgaleal adhesions in that area. CONCLUSION: Ahove the zygomatic arch, the FTBFN is not protected by the galea. During bicoronal approaches, if only the superolateral angle of the orbital rim needs to be exposed and not the zygomatic arch, there is no need to protect the FTBFN using an interfascial approach.
Anatomy, Artistic↗
Combined supra/infratentorial-transsinus approach to large pineal region tumors.
OBJECT: The authors sought to confirm that the combined supra/infratentorial-transsinus approach offers a safer means of resecting large pineal region tumors than other approaches currently being used. The aforementioned method provides a wider exposure of the pineal region with less brain retraction than the infratentorial-supracerebellar or the occipital-transtentorial approach alone and is applicable to some large and giant tumors of this area. This combined approach was used in six patients to remove large pineal region tumors including four tentorial meningiomas, one pineocytoma, and one epidermoid cyst. METHODS: The transverse sinus and tentorium were sectioned after review of preoperative angiographic studies, after taking intraoperative measurements of the venous pressure in the nondominant transverse sinus before and after clipping and while monitoring the somatosensory evoked potentials. The occipital lobe cortex and cerebellum were retracted slightly along the tentorium. Deep veins of the galenic system, the quadrigeminal area, and the tumor were well exposed. Before it was used for tumor resection the approach was studied in five cadaveric head specimens, and the projection of different approaches was compared radiologically. The tumors were removed in a gross-total manner in all patients, and none of the major veins of the galenic system was injured. Resuturing of the nondominant transverse sinus was performed postoperatively in one patient. One of the six patients experienced transient visual loss, and another suffered mild right sixth cranial nerve paresis; however, both recovered in 3 weeks. The wide exposure of the combined approach was also confirmed on radiological and anatomical studies. CONCLUSIONS: The combined supra/infratentorial-transsinus approach is preferred for the resection of certain large pineal region tumors.
Abducens Nerve↗
Multiple meningiomas and intracranial aneurysms: a case report and review of the literature.
An extremely rare case with multiple meningiomas and multiple aneurysms is reported. This 48 year-old female had her meningiomas at the convexity and along the sphenoid wing, and intracranial aneurysms at the basilar tip, left middle cerebral artery bifurcation, and left pericallosal artery. All of them were shown by preoperative radiological evaluation. During the operation, two more meningiomas, again at the sphenoid wing and at the tentorium, were found. There was no evidence of either a connective tissue disease or neurofibromatosis.
Female↗