Spontaneous nonpulsatile aneurysm of the superficial temporal artery mimicking a subcutaneous mass lesion.

True superficial temporal artery (STA) aneurysms are extremely rare and usually atherosclerotic in origin. Here the authors report a 62-year-old man with a nonpulsatile mass lesion at the trace of the right STA that was surgically excised with a preoperative diagnosis of subcutaneous mass lesion, preoperatively and histopathologically found out to be a thrombosed true STA aneurysm. Preoperative evaluation, differential diagnosis, and management of such lesions are discussed.

Bilateral Temporal Bone Xanthomas in Type II Hypercholesterolemia.

We present a very rare case of intracranial xanthoma with bilateral temporal bone involvement. The lesion caused destruction and remodelling in mastoid air cells. On the right side, cerebellar compression was obvious. The patient was operated on the symptomatic side and the lesion was totally removed.

The effects of intravenous cilostazol and nimodipine on cerebral vasospasm after subarachnoid hemorrhage in an experimental rabbit model.

AIM: Our aim in this study was to investigate the efficacy of intravenous administration of cilostazol and compare these effects with intravenous usage of nimodipine in subarachnoid hemorrhage model. MATERIAL AND METHODS: Twenty-five male New Zealand White rabbits were assigned randomly to 1 of 5 groups. Animals in group 1 (n=5) served as controls, group 2 (n=5) was the SAH-only group, group 3 (n=5) was treated with intravenous 10 mg/kg cilostazol, group 4 (n=5) was treated with 0.05 mg/kg intravenous nimodipine, and group 5 (n=5) served as the vehicle group and treated with a mixture of dimethyl sulfoxide and phosphate buffer solution. Basilar arteries were removed from the brain stems and analyzed. The vessels were measured using computer-assisted morphometry (SPOT for Windows Version 4.1). Statistical comparisons were performed using the Kruskall-Wallis and Mann-Whitney U tests. RESULTS: Basilar artery wall thicknesses in group 3 and 4 were smaller than the group 2 and this was statistically significant at p < 0.05. The mean arterial cross-sectional areas in group 3 and 4 were higher than group 2 and this was also statistically significant at p < 0.05. CONCLUSION: Our results demonstrate that intravenous administration of both cilostazol and nimodipine significantly attenuates cerebral vasospasm after SAH.

Enlargement of postoperative aqueductal air due to elevated body temperature. Case report.

Pneumocephalus has been reported after posterior fossa surgery especially with procedures performed in the sitting position. The gravitational effect is the decisive factor in the development of pneumocephalus. The entrapped air in the aqueduct may enlarge due to several factors such as elevated body temperature and may cause to deterioration in neurological status. We report a rare case of tension pneumocephalus associated with the enlargement of massive air in aqueduct due to elevated body temperature, following removal of a cervicomedullary tumor. We believe her neurological deterioration was due to the compression of the reticular formation by dilatation of postoperative air in the aqueduct due to the elevation of her body temperature.

Existence of cotton granuloma after removal of a parasagittal meningioma: clinical and radiological evaluation -a case report-.

Hemostatic agents, routinely used in neurosurgery to achieve intraoperative hemostasis may cause foreign body reaction. These may produce clinically symptomatic and radiologically apparent mass lesions. It should be kept in mind that retained cotton or rayon materials may mimic the appearance of a tumor or an abscess on MRI scan, especially at sides of previous craniotomies. Here we report a case of intracranial foreign body granuloma which occurred due to remained cottonoid after removal of a parasagittal meningioma. This entity was also documented by MR imaging technics included diffusion weighted, flair and ADC mapping.

Spontaneous resolution of syringomyelia without Chiari malformation.

A 30-year-old woman presented with a cervical syrinx manifesting as hemihypesthesia. Neuroimaging found no evidence of Chiari malformation or tight cisterna magna. Serial magnetic resonance imaging studies over a 6-year period demonstrated spontaneous and complete resolution of the syrinx accompanied by an asymptomatic clinical course. The natural history of syringomyelia is highly unpredictable. The outcome of surgical treatment for patients with syringomyelia is not always satisfactory, so the indications for surgery are controversial. Spontaneous resolution of syringomyelia unrelated with foramen magnum lesion has various causes. Close follow up of the patient is necessary to monitor for recurrence.

Abducens nerve palsy in a patient with a parasagittal meningioma--case report.

A 67-year-old female presented with isolated unilateral abducens nerve palsy progressing in 10 days. There were no signs of elevated intracranial pressure. Magnetic resonance imaging revealed a right parasagittal meningioma. The tumor was grossly totally removed and the patient's nerve palsy gradually improved within 3 weeks. The mechanism of the isolated abducens nerve palsy in this case is attributed to compression of the abducens nerve by entrapment of the cerebrospinal fluid just before entering Dorello's canal under the petrolingual ligament. Linear forces in the midsagittal plane due to the mass effect of the tumor may have temporarily increased the local cerebrospinal fluid pressure and caused 'pseudoentrapment' of the abducens nerve.

Epidermoid cyst of the brain stem symptomatic in childhood.

BACKGROUND: Epidermoid cysts may remain asymptomatic for a long period of time due to their slowly growing pattern corresponding with the normal human skin turnover time and due to soft and light cyst content. They do not cause compression of neural and vascular structures initially that is why almost all of the cases in the literature are diagnosed during adulthood. METHODS: We report here an epidermoid cyst in childhood, which was located in the medulla oblongata, unusually and atypically with liquefied cyst content. The liquefaction may occur due to an intrauterine or early childhood infection. The reported case also suffered previously a severe respiratory infection. Although the cyst is located in and around a highly eloquent neural area, plasticity of the brain stem prevented neurological deterioration due to this very slow growing extraaxial mass lesion. The ordinary cyst content found in the center of the cyst cavity during the operation suggested that the same ordinary material, which was previously at the periphery, ran to get liquefied in time. CONCLUSION: We suggest that the symptoms of this present case appeared very early due to liquefaction of the cyst content with compression and displacement of the brain stem caudally. The recent infection process may predispose the pathological condition.

Proposed classification of segments of the internal carotid artery: anatomical study with angiographical interpretation.

The nomenclature and borders of the segments of the internal carotid artery (ICA) remain confusing. A classification of segments of the ICA is proposed based on constant anatomical structures, such as the carotid foramen and canal, the petrous bone, the petrolingual ligament (PLL), and the proximal and distal dural rings. The bilateral ICAs were dissected in 15 cadaveric head specimens using different neurosurgical approaches. The bilateral lacerum foramina were studied in five dry skulls. The bilateral segments of the ICA were also examined on carotid angiograms of 10 normal patients and another with the ophthalmic artery originating from the intracavernous portion of the ICA. The present classification divides the ICA into five segments in the direction of the blood flow. The cervical segment is extradural and extracranial, the petrous segment is extradural and intraosseous, the cavernous segment is interdural and intracavernous, the clinoidal segment is interdural and paracavernous, and the cisternal segment is intradural and intracisternal. The ICA did not pass through the lacerum foramen in any specimen. In all specimens, 1/8 to 5/8 of the lacerum foramen was under the deep dural layer of the cavernous sinus. The term 'lacerum segment' as used previously and called the 'trigeminal segment' by us cannot be justified. The PLL is the posterolateral border of the cavernous sinus and the lacerum and trigeminal segments should be included in the cavernous and petrous segments. The ophthalmic artery may originate from the clinoidal ICA, from the cavernous ICA, or from the middle meningeal artery. Instead of using the term 'ophthalmic segment,' the term 'cisternal segment' should be used for the anatomically distinct ICA in the subarachnoid space. This classification should be minimally affected by anatomical variations.

Minimally invasive anterior contralateral approach for the treatment of cervical disc herniation.

BACKGROUND: During the practice of ipsilateral approach to the offending lesion in anterior simple discectomy, the authors realized that it achieves better surgical exposure of the opposite foraminal area. In addition, it was also realized that routine procedures for better visualization of the foraminal area, such as stripping longus colli muscles, further excising of the anterior longitudinal ligament, or using a spreader, which cause more invasive surgery during the standard anterior approach, are not necessary because the contralateral approach already achieves sufficient exposure of the target foraminal area. OBJECTIVE: Evaluation of the results and effectiveness of this minimal invasive technique in patients with either soft or hard disc herniations. METHODS: Between January 1994 and April 2002, 216 patients underwent anterior contralateral microdiscectomy without fusion for cervical disc herniation at 1 or 2 adjacent levels. Anterior contralateral microdiscectomy is a less invasive technique than standard anterior simple discectomy in which longus colli muscles are not stripped, and the lateral part of annulus fibrosis at the side of intervention and ventrolateral part of it at the opposite side are not removed. In addition, a mini Zenker handheld retractor is used for retraction of paravertebral soft tissues and a spreader is not used during the discectomy procedure. There were 182 patients diagnosed with radiculopathy and 34 patients with myelopathy. Assessments of the neurological status of patients with radiculopathy were done by physical examinations, and of those with myelopathy according to the modified Japanese Orthopaedic Association cervical spine functional assessment scale. These neurological assessments were repeated in the 18th month after surgery. In the follow-up period, the outcomes of surgery were also assessed for all patients in 4 categories, from failure to excellent. RESULTS: Surgery outcomes generally have been good to excellent and none of the patients were made worse by the procedure. The outcomes were significantly better in the radiculopathy and soft disc herniation groups. Other positive outcome factors were short duration and sudden onset of symptoms, normal cervical curvature, and single-level disease. Follow-up radiological studies revealed fibrous healing with normal or slight loss of disc height in 199 (92.1%) patients and total obliteration of the involved disc space representing radiological fusion signs in 13 (6%) patients. The overall complications observed in this study were 2 spontaneous and 2 postinfection collapses of disc level, 1 excessive fibrosis of disc level, and 2 adjacent-level diseases. CONCLUSION: Anterior contralateral microdiscectomy without fusion achieves better exposure for resection of the offending foraminal or far lateral lesions, ventral osteophytes, or a disc fragment under direct microscopic visualization. Collapse and instability of the involved disc level can also be avoided via this less invasive technique.

The trigeminal nerve and ganglion: an anatomical, histological, and radiological study addressing the transtrigeminal approach.

BACKGROUND: The transtrigeminal route with splitting of the trigeminal ganglion (TG) is a skull base approach used to expose the posteromedial part of the cavernous sinus (CS), the base of the TG, and the petrolingual ligament (PLL). METHODS: To verify the transtrigeminal approach (TTA), the 3 divisions of the trigeminal nerve (TN), the so-called TG, and the trigeminal root were analyzed anatomically, histologically, and radiologically. The anatomic study was performed bilaterally in 5 cadaveric head specimens. For the histologic study, 6 TN specimens removed from cadavers were used. In addition, the radiologic demonstration of the TN and its so-called ganglion was performed on 5 cases by magnetic resonance imaging (MRI) scan. RESULTS: The TN is composed of linear, crossing, and connecting rootlets. These 3 types of rootlets indicate a plexiform constitution rather than a ganglion even though there are ganglionic cells. Consequently, the term "trigeminal plexus" may be preferred to describe this network. In our new proposed classification, the segments of the TN can be divided into 6 portions according to their relationship with the brainstem, the cisterns, and the bone structures. The first 3 segments before separating into 3 divisions are (1) pontine, (2) cisternal (preganglionic or preplexal), (3) gasserian (ganglionic or plexal). The last 3 segments after the division are (4) preforamino-fissural (postganglionic or postplexal), (5) foramino-fissural, and (6) extracranial (postforamino-fissural). A loose connective tissue along the rootlets of the maxillary and the mandibular divisions of the TN at the gasserian (ganglionic or plexal) segment enabled us to split the so-called "trigeminal ganglion" or "gasserian ganglion" to perform the TTA. CONCLUSION: The TTA is possible, useful, and necessary in selected cases with invasion of the posteromedial part of the CS.

Multilevel acute spinal epidural hematoma in a patient with chronic renal failure--case report.

A 47-year-old female with diabetic nephropathy presented with acute onset of severe back pain and progressive weakness in both lower extremities. Neuroimaging revealed a spinal epidural hematoma extending from the T-3 vertebra to the sacrum. Removal of all or every other lamina on levels with epidural hematoma and emergent evacuation of the hematoma were planned. T-9 and T-10 laminectomies were performed, but excessive bleeding during the operation prompted us to abandon the procedure. Plasma and desmopressin administration controlled the bleeding from the drain 8 hours after the operation. Follow-up neuroimaging one month later revealed total resolution of the hematoma with improved neurological status. Acute spinal epidural hematomas extending over more than 15 segments are extremely rare and the surgical treatment is still challenging. Coexisting hemorrhagic diathesis creates more problems. Conservative treatment may be the best option.

The effects on prognosis of surgical treatment of hypertensive putaminal hematomas through transsylvian transinsular approach.

OBJECTIVE: Hypertensive putaminal hematoma (HPH) is a devastating type of stroke that mostly results in death or severe neurologic deficit. There seems to be no general agreement on the selection of treatment modality for individual patients. In this study a comparison has been made between conservative treatment and the results of surgical treatment through the transsylvian transinsular approach of HPH with 30 cc or more. METHODS: Sixty-six patients with 30 cc volume or over of HPH, who were admitted within 36 hours after ictus, have been included in this study. Selection of the patients was made primarily according to the computerized tomography scan (CT) findings on admission. Out of the 66 patients, 47 were operated for hematoma evacuation through transsylvian transinsular approach, and the remaining 19 were accepted as a control group to be treated conservatively after their relatives declined authorization for surgery. All patients' neurologic grades and CT findings on admission were classified according to the hypertensive intracerebral hemorrhage grading system, as proposed by the cooperative study in Japan. After 6 months the outcomes of both groups were assessed according to the Glasgow outcome scale (GOS). RESULTS: The statistical difference between the mortality rates was considerable (p < 0.05) with ratios of 34% and 63.1% in the surgically and conservatively treated groups, respectively. Good recovery, that is GOS score 5, was not observed in either group. In the group of surgically treated patients, 27.7% was eventually moderately disabled (GOS score 4); whereas this ratio was 5.3% among the conservatively treated group, giving a statistically significant difference (p < 0.05). Our results indicate that neurologic grades and CT findings on admission are good predictors of outcome, as the grades increase the outcome worsens. Furthermore, ventricular spread of hematoma is not a good prognostic factor. CONCLUSIONS: Surgical treatment via transsylvian transinsular approach of HPH with a volume of 30 cc or more results in improved outcome as compared to conservative treatment. Operation time within the first 36 hours after ictus did not affect the outcome.

Spontaneous subfalcial transcallosal migration of a missile to the contralateral hemisphere causing deterioration in neurological status--case report.

A 26-year-old man sustained a gunshot injury. Computed tomography (CT) demonstrated the missile in the right parietal region. Twenty-four hours later, the missile had moved towards the midline. Following slight deterioration in his neurological condition one week later, follow-up CT revealed that the missile had crossed the midline through the corpus callosum and was located in the left parietal region. CT during the second week demonstrated that the missile had stopped close to the left parietal bone. Spontaneous migration of a missile to the contralateral side via a subfalcial-transcallosal route with deterioration in neurological status is unusual. The missile may have moved under the influence of the intracranial pressure and pulsatile effect of the cerebrospinal fluid.