Incidence and Predictive Factors of Cerebral Hyperperfusion After Extracranial-Intracranial Bypass for Occlusive Cerebrovascular Diseases

BACKGROUND:

Although many studies of postoperative cerebral hyperperfusion syndrome (CHS) after carotid endarterectomy have been reported, there are few reports related to extracranial-intracranial (EC-IC) bypass for atherosclerotic occlusive cerebrovascular diseases.

OBJECTIVE:

To examine the incidence of cerebral hyperperfusion and CHS after EC-IC bypass and to investigate predictive factors.

METHODS:

Fifty consecutive patients undergoing EC-IC bypass for atherosclerotic occlusive cerebrovascular diseases were studied. Immediately after bypass surgery, resting regional cerebral blood flow was determined under continuous sedation, and postoperative hyperperfusion was evaluated according to the definitions as follows: > 50% increase in regional cerebral blood flow compared with the contralateral side (method 1) and > 100% increase in corrected regional cerebral blood flow compared with preoperative values (method 2). Logistic regression analysis was conducted to determine the effect of multiple variables on postoperative hyperperfusion.

RESULTS:

Transient symptoms of CHS were observed in 3 patients. Cerebral hyperperfusion was detected in 12 patients (24%) as defined by method 1 and in 9 patients (18%) by method 2. Postoperative hyperperfusion occurred significantly more frequently in patients with the steal phenomenon (regional cerebral vasoreactivity ≤ 0%; P = .001 by method 1 and P = .001 by method 2) and correlated with impaired preoperative regional cerebral vasoreactivity (P < .001). Logistic regression analysis revealed that the steal phenomenon was a significant risk factor for hyperperfusion as defined by both methods 1 (P = .009) and 2 (P = .03).

CONCLUSION:

The incidence of cerebral blood flow-assessed postoperative hyperperfusion after EC-IC bypass for atherosclerotic occlusive cerebrovascular diseases was not rare. Post EC-IC bypass CHS could be reduced by continuous, strict blood pressure control under sedation.

Contrast medium-induced seizures and prolonged motor weakness after cerebral angiography: case report

BACKGROUND AND IMPORTANCE

Neurological complications of cerebral angiography are usually embolic events resulting in stroke or seizure of vascular origin. Contrast media rarely induce neurological complications.

CLINICAL PRESENTATION

Repeated seizures and prolonged motor weakness developed in a 26-year-old woman after cerebral angiography. Neurological deficits remained the next day with slow recovery. Repeat magnetic resonance imaging did not demonstrate any cerebral ischemia even on diffusion-weighted images. The contrast medium was the most likely cause of the neurological deficits. She recovered completely after infusion of the osmotic diuretic.

CONCLUSION

Although rare, we should take into consideration that contrast media may induce neurological complications after cerebral angiography.

Clival inflammation with cavernous sinus thrombophlebitis and orbital subperiosteal abscess--case report

A 64-year-old woman presented with a very rare case of three infectious lesions, cavernous sinus thrombophlebitis, clival inflammation, and orbital subperiosteal abscess (SPA), manifesting as abducens palsy. An isolated non-specific mass in upper clivus was initially suspected to be derived from paranasal sinusitis. The clival lesion was approached by an endonasal transsphenoidal route and diagnosed as inflammation. However, progressive enlargement of an orbital mass was recognized, with eyelid erythema and swelling. Magnetic resonance imaging showed massive paranasal sinusitis and an intra-orbital mass, which was proved to be an orbital SPA by open surgery. Cavernous sinus thrombophlebitis might have been caused by primary paranasal sinusitis, and the origin of orbital cellulitis was suspected to be cavernous sinusitis based on the preoperative radiological findings. These unusual lesions should be kept in mind as one of the differential diagnoses.

Anterior interhemispheric approach for 100 tumors in and around the anterior third ventricle

OBJECTIVE

We report our experience with anterior interhemispheric approach for tumors in and around the anterior third ventricle, including surgical technique, instrumentation, pre- and postoperative hormonal disturbances, and resection rate.

METHODS

One hundred patients with 46 craniopharyngiomas, 12 hypothalamic gliomas, 12 meningiomas, 6 hypothalamic hamartomas, and 24 other lesions were operated on using an anterior interhemispheric approach with or without opening of the lamina terminalis. This surgical approach involves no frontal sinus opening; a narrow (approximately 15-20 mm in width) access between the bridging veins, which is sufficient to remove the tumor totally; and sparing of the anterior communicating artery. Specially designed long bipolar forceps and scissors are necessary for this approach, and concomitant use of angled instruments (endoscope, aspirator, and microforceps) is required frequently. The postsurgical follow-up period varied from 4 months to 18 years.

RESULTS

Total removal of the neoplasm was accomplished in 37 of 46 patients with craniopharyngiomas (80.4%), whereas subtotal resection was performed in hypothalamic gliomas. No significant differences in pre- and postoperative hormonal disturbances were observed in 37 craniopharyngiomas and 10 hypothalamic gliomas. There was no operative mortality. Visual acuity was preserved or improved in 68 of 75 patients assessed. The Karnofsky Performance Scale score did not deteriorate in 72 of 75 patients tested.

CONCLUSION

The minimally invasive anterior interhemispheric approach, with or without opening of the lamina terminalis, is useful for removal of tumors in and around the anterior third ventricle, such as craniopharyngiomas and hypothalamic gliomas.

Individualized high-dose cabergoline therapy for hyperprolactinemic infertility in women with micro- and macroprolactinomas

CONTEXT

Cabergoline is effective for hyperprolactinemic hypogonadism. However, the rate of cabergoline-induced pregnancy in women with prolactinoma remains unknown. Also unknown is whether cabergoline can control tumor growth and thereby achieve successful pregnancy in patients with macroprolactinomas.

METHODS

Eighty-five women with macroprolactinomas (n = 29) or microprolactinomas (n = 56) received prospective, high-dose cabergoline therapy for infertility based on individual prolactin suppression and/or tumor shrinkage. The patients included 31 bromocriptine-resistant, 32 bromocriptine-intolerant, and 22 previously untreated women. Conception was withheld until three regular cycles returned in women with microadenoma and until tumors shrank below 1.0 cm in height in women with macroadenoma. Cabergoline was withdrawn at the fourth gestational week.

RESULTS

Cabergoline normalized hyperprolactinemia and recovered the ovulatory cycle in all patients. All adenomas contracted, and 11 macroadenomas and 29 microadenomas disappeared. Eighty patients (94%) conceived 95 pregnancies, two of which were cabergoline-free second pregnancies. The dose of cabergoline at the first pregnancy was 0.25-9 mg/wk overall and 2-9 mg/wk in the resistant patients. Of the 93 pregnancies achieved on cabergoline, 86 resulted in 83 single live births, one stillbirth, and two abortions; the remaining seven were ongoing. All babies were born healthy, without any malformations. No mothers experienced impaired vision or headache suggestive of abnormal tumor reexpansion throughout pregnancy.

CONCLUSION

Cabergoline achieved a high pregnancy rate with uneventful outcomes in infertile women with prolactinoma, independent of tumor size and bromocriptine resistance or intolerance. Cabergoline monotherapy could substitute for the conventional combination therapy of pregestational surgery or irradiation plus bromocriptine in macroprolactinomas.

Optimal treatment strategy for craniopharyngiomas based on long-term functional outcomes of recent and past treatment modalities

Although many authors have described treatment strategies for craniopharyngiomas, the optimal treatment of craniopharyngiomas remains controversial. This study aimed to define an adequate surgical strategy for craniopharyngiomas by reviewing the long-term functional performance of patients treated by current and past treatment modalities. Fifty-five patients with longer than 5 years of follow-up were selected for the present long-term study. The duration of follow-up ranged from 5.5 to 33 years (median, 14.8 years). There were 28 adult patients (14 males; median age, 44.4 years) and 27 children younger than 16 years of age (15 males; median age, 8.1 years). The patients were divided into the following treatment groups: single surgery (group A; n=14 multiple surgeries (group B; n=8), surgery or surgeries followed by radiotherapy (group C; n=23), surgery or surgeries (partial removal) followed by radiotherapy + additional treatments (multiple surgeries and/or re-irradiation; group D; n=10). In addition to the routine assessments of neurological, endocrine, and visual outcomes, the level of daily functioning was analyzed using the Karnofsky Performance Scale (KPS). Statistical analysis of relationship between KPS score and treatment mode demonstrated that group D had a significantly lower KPS score (F=5.82, p=0.0017). Furthermore, mortality, cognitive function, and visual function were significantly better in groups A, B, and C than in group D. Multiple regression analysis demonstrated that cognitive dysfunction, visual disturbance, and treatment mode were independent covariates that significantly affected postoperative KPS score. Adequate primary treatment for craniopharyngiomas is important to avoid subsequent multiple treatments. Craniopharyngiomas should be removed surgically as far as possible but without further deteriorating cognitive and visual functions, either as total resection or subtotal resection with a small remnant that is controllable by radiation therapy.

Novel method for controlling cerebrospinal fluid flow and intracranial pressure by use of a tandem shunt valve system

OBJECTIVE

Programmable shunt valve systems have improved the management of patients with hydrocephalus. However, associated problems such as over-drainage and slit-like ventricles, even in patients with anti-siphon devices installed, still remain unresolved.

METHODS

We conceived a novel tandem shunt valve system to overcome the problems with existing shunt valve systems. Experiments were performed in vitro and a manometer was used to measure the results.

RESULTS

Manometric measurements in vitro with the tandem shunt valve system demonstrated that it effectively controlled the final pressure under varying flow rates. This novel system was applied to 2 intractable cases (over-drainage and slit-like ventricles) with good results.

INTERPRETATION

The tandem shunt valve system has therapeutic potential not only for over-drainage and slit-like ventricles, but also for uncontrollable hydrocephalus, by precisely controlling the cerebral spinal fluid flow rate.

Immunohistochemical detection of 13(R)-hydroxyoctadecadienoic acid in atherosclerotic plaques of human carotid arteries using a novel specific antibody

13-Hydroxyoctadecadienoic acid (13-HODE) is a major component of oxidized low density lipoprotein (OxLDL), which has been shown to have a crucial role in atherogenesis. Of the 13-HODE stereoisomers, 13(S)-HODE and 13(R)-HODE, little is known about the latter in contrast to the former. To detect 13(R)-HODE in atherosclerotic lesions, we prepared a mouse monoclonal antibody against 13(R)-HODE. Competitive enzyme-linked immunosorbent assay clarified the selective reaction of a clone mAb 13H1 with both free and bovine serum albumin-conjugated forms of 13(R)-HODE but not other oxidized lipids including 13(S)-HODE. Immunohistochemical analysis revealed the colocalization of 13(R)-HODE immunoreactivity with the OxLDL marker oxidized phophatidylcholine immunoreactivity in vascular endothelial cells, macrophages and migrating vascular smooth muscle cells in atherosclerotic plaques of human carotid arteries. The present results provide in vivo evidence for the formation of 13(R)-HODE in atherosclerotic lesions of carotid arteries.

Application of contrast-enhanced constructive interference in steady state magnetic resonance imaging to Leksell GammaPlan for localizing c2-c3 aneurysms: technical note

OBJECTIVE

We used gadolinium (Gd)-enhanced constructive interference in steady state (CISS) magnetic resonance imaging with the Leksell GammaPlan (LGP; Elekta AB, Stockholm, Sweden) system for accurate preoperative evaluation of the anatomic localization of intradural and/or extradural C2-C3 aneurysms.

METHODS

Anatomic localization of 8 unruptured aneurysms of the C2-C3 segment was evaluated using Gd-enhanced CISS imaging with LGP. Four patients diagnosed with intradural aneurysms, 1 with a combined intraextradural aneurysm, and 1 with an intracavernous aneurysm underwent operation. The aneurysmal localizations diagnosed preoperatively by Gd-enhanced CISS imaging with LGP were compared with intraoperative findings.

RESULTS

By use of Gd-enhanced CISS imaging with LGP, 3-dimensional visualization of the internal carotid artery, aneurysms at the C2-C3 segment, optic nerve, oculomotor nerve, cavernous sinus, and anterior clinoid process was possible in 8 patients. The localization of intradural or combined intra-extradural aneurysms was diagnosed on the basis of the oculomotor nerve and the cavernous sinus depicted in 3-dimensional images. The oculomotor nerve and the cavernous sinus serve as landmarks for the proximal ring on images of the carotico-oculomotor membrane. Intradural or intra-extradural localization of C2-C3 aneurysms with this novel technique was in complete agreement with intraoperative findings in 6 surgical cases.

CONCLUSION

This study demonstrated the utility of Gd-enhanced CISS imaging used with LGP for accurate preoperative localization of intradural and/or extradural aneurysms at the C2-C3 segments.

Pressure-controlled dual irrigation-suction system for microneurosurgery: technical note

OBJECTIVE

We designed a new irrigation-suction system consisting mainly of a pressure-resistant irrigation fluid container, dual irrigation and suction devices, and an intracontainer pressure regulator.

METHODS

The intracontainer pressure can be regulated from 0 to 0.02 MPa. This system is simple and can be operated simultaneously by both an operator and an assistant. It is powered by compressed air, which is available in regular operating rooms of any hospital.

RESULTS

No complications including blood clots in the brain and vascular injuries related to this system were observed.

CONCLUSION

The excellent and safe performance of this dual irrigation-suction system in clearing the operating field by an operator and/or an assistant has been proven in more than 300 neurosurgical operations.

Histological findings at the boundary of craniopharyngiomas

Although a craniopharyngioma is grossly well circumscribed, microscopically the borders are frequently irregular and may be associated with gliosis in the adjacent brain tissue. In the current study, we investigated the histology of the interface between craniopharyngiomas and surrounding normal structures such as the hypothalamus and pituitary gland. Histologically, we classified the findings at the boundary of craniopharyngiomas into three types. In type 1, a relatively thick capsule-like tissue was identified at the boundary between the craniopharyngioma and surrounding normal structure composed of tumor cells and inflammatory changes. In type 2, a craniopharyngioma had a relatively clear cleavage between the surrounding gliosis. In type 3, the boundary had some interdigitation of the tumor in the surrounding gliotic layer adjacent to the craniopharyngioma. In types 1 and 3, surgeons may fail to accomplish complete resection of the tumor. These histological features may result in recurrence of craniopharyngioma even after gross total resection.

Multiple primary cranial Ewing's sarcoma in adulthood: case report

OBJECTIVE

Ewing's sarcoma is a malignant bone tumor occurring most frequently in the long bones and flat bones as a solitary lesion during the first 2 decades of life. Ewing's sarcoma and peripheral primitive neuroectodermal tumor have recently been considered to be the same entity because of histological and molecular similarities.

CLINICAL PRESENTATION

A 25-year-old man presented with swelling in the right parietal region. Magnetic resonance imaging scans showed 2 mixed intense mass lesions in the right parietal and left frontal areas with heterogeneous gadolinium enhancement. A computed tomographic scan revealed osteolytic changes of the inner calvarial bone. Ga-67 citrate scintigraphy demonstrated abnormal uptake in the right parietal and the left frontal areas consistent with the findings on magnetic resonance imaging scans. There was no uptake lesion beyond the cranium. The patient underwent surgical excision of the right parietal lesion.

INTERVENTION

Histological examinations showed densely packed, small round cells with rosette formation. The cells had scanty clear cytoplasm, and regular vesicular and hyperchromatic nuclei. Electron microscopy showed little differentiation to neuronal tissue, indicating Ewing's sarcoma. After surgical treatment, conventional whole cranial irradiation of 40 Gy and chemotherapy were conducted. The tumor in the left frontal region disappeared. Follow-up examinations showed no evidence of recurrence 1 year after the surgery.

CONCLUSION

Although quite rare, Ewing's sarcoma should be taken into consideration as a differential diagnosis of multiple cranial mass lesions in adulthood.

POSTCAROTID ENDARTERECTOMY CEREBRAL HYPERPERFUSION CAN BE PREVENTED BY MINIMIZING INTRAOPERATIVE CEREBRAL ISCHEMIA AND STRICT POSTOPERATIVE BLOOD PRESSURE CONTROL UNDER CONTINUOUS SEDATION

OBJECTIVE

Cerebral hyperperfusion syndrome is a major complication after carotid endarterectomy (CEA). We investigated whether our strategy of minimizing intraoperative cerebral ischemia and strict postoperative blood pressure control under continuous sedation prevented postoperative hyperperfusion.

METHODS

Eighty consecutive patients undergoing CEA were studied. A shunt was used in all patients during CEA. All patients were managed postoperatively under continuous sedation for as long as 48 hours on the basis of the regional cerebral blood flow (rCBF) measured immediately after CEA. Postoperative hyperperfusion was assessed, on the basis of the cerebral blood flow study under sedation (propofol) after CEA, either as a greater than 30% increase in rCBF compared with the contralateral side, or a greater than 100% increase in the corrected rCBF (calculated from percentage reduction of the contralateral rCBF induced by propofol) compared with preoperative values.

RESULTS

No patient developed cerebral hyperperfusion syndrome. Postoperative hyperperfusion was found at very low rates (2.5% in the middle cerebral artery territory and 1.3% in the anterior cerebral artery territory by definition 1, and 0% in both territories by definition 2). Ratios of regional oxygen saturation after internal carotid artery clamping to preclamp baseline values were greater than 0.9 in 78 of 80 patients, indicating very mild intraoperative cerebral ischemia. Parameters related to cerebral ischemia during CEA, such as regional oxygen saturation, internal carotid artery cross-clamping duration, and stump pressure (index), did not affect the incidence of postoperative hyperperfusion.

CONCLUSION

The present study suggests that minimizing intraoperative cerebral ischemia using a shunt, followed by strict postoperative blood pressure control under continuous sedation, can prevent post-CEA hyperperfusion.

Prospective study of high-dose cabergoline treatment of prolactinomas in 150 patients

CONTEXT

Cabergoline fails to normalize hyperprolactinemia in a considerable proportion of prolactinomas, especially macroadenomas.

OBJECTIVE

We examined the effect of individualized high-dose cabergoline treatment on hyperprolactinemia in prolactinomas.

PATIENTS

The study included 122 women and 28 men (93 microadenomas and 57 macroadenomas). Forty-seven had undergone transsphenoidal surgery. According to the preceding medical treatment, the participants were separated into untreated (group U; n = 60), intolerant (group I; n = 64), and resistant (group R; n = 26) groups.

INTERVENTIONS

We promptly increased cabergoline dose on the basis of individual prolactin levels. Length of treatment was 1 yr.

RESULTS

Cabergoline normalized hyperprolactinemia in all patients except one. The proportion of prolactin normalization in both groups U and I was 83% at 3 months and 95% at 6 months. By contrast, that in group R was 35% at 3 months and 58% at 6 months. Mean cabergoline dose in milligrams per week at the time of prolactin normalization was 2.0 +/- 0.3 in group U, 0.9 +/- 0.1 in group I, and 5.2 +/- 0.6 in group R. Prolactin normalization rate at the 3 mg/wk dose was 84% overall but only 35% in group R. Serum progesterone or testosterone levels, diminished in 122 women or 16 men, respectively, were recovered in all except one resistant and four postmenopausal or panhypopituitary patients.

CONCLUSION

Individualized high-dose cabergoline treatment can normalize hyperprolactinemia and hypogonadism in nearly all prolactinomas irrespective of tumor size or preceding treatments. Hyperprolactinemia could be controlled in poor responders within 1 yr with doses higher than 3 mg/wk.

Possible role of single-voxel (1)H-MRS in differential diagnosis of suprasellar tumors

The objective of the present study was investigation of the possible role of proton magnetic resonance spectroscopy ((1)H-MRS) for differential diagnosis of suprasellar tumors. Forty patients (23 men and 17 women; median age, 45 years) with suprasellar, hypothalamic, and third ventricle neoplasms underwent long-echo (TR: 2000 ms, TE: 136 ms, 128-256 acquisitions) single-voxel (1)H-MRS before surgical treatment. The volume of the voxel was either 3.4 cc or 8 cc. Spectroscopic data were analyzed by calculation of the various metabolite ratios as well as by determination of the type of the pathological (1)H-MR spectra. There were 19 pituitary adenomas, 7 gliomas, 5 craniopharyngiomas, 3 chordomas, meningioma, hemangiopericytoma, malignant lymphoma, germinoma, Rathke cleft cyst, and hypothalamic hamartoma (one of each). Six tumors were recurrent after initial surgical resection with or without irradiation. Comparison of the individual metabolite ratios revealed only few subtle differences among neoplasms. In the same time, pattern analysis with determination of the type of the pathological (1)H-MR spectra disclosed certain specific characteristics, which seemingly can be used for tumor typing. Meanwhile, metabolic imaging was less effective for characterization of recurrent neoplasms. In conclusion, in cases of initially diagnosed suprasellar tumors with involvement of the hypothalamus and extension into the third ventricle pattern analysis of the single-voxel (1)H-MRS can provide valuable information, which, in addition to structural MRI, can be effectively used for diagnostic purposes.

Endoscopic trans-sphenoidal surgery for pituitary tumors

Trans-sphenoidal surgery, which is the most widely used technique for the treatment of pituitary tumors, has continued to evolve by introducing new approaches and technologies, such as the direct endonasal route and the endoscope. The endonasal approach is a minimally invasive route to the sella turcica with the advantages of using a simpler and more rapid nasal dissection and eliminating the nasal and lip complications. Restricted exposure provided by the endonasal approach is overcome by combined use of an endoscope that provides a more panoramic view of the surgical field beyond the area covered by the operating microscope. An operating microscope permits binocular vision and bimanual technique, which are familiar to neurosurgeons. Neurosurgeons should exploit the advantages of both modalities for the benefit of patients. This review describes the advances in trans-sphenoidal surgery focusing on the endoscopic approach.

External carotid endarterectomy followed by superficial temporal artery to middle cerebral artery anastomosis for internal carotid artery occlusion with advanced ipsilateral external carotid stenosis

OBJECTIVE

For patients with internal carotid artery occlusion with advanced narrowing of the ipsilateral external carotid artery (ECA), we performed preventive carotid endarterectomy (CEA) for the ECA stenosis before superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis for internal carotid artery occlusion.

METHODS

Between August 2002 and July 2005, we treated seven patients with such lesions, six men and one woman, ranging in age from 52 to 66 years (median, 60 yr). Before STA-MCA anastomosis, we performed preventive CEA for advanced ECA stenosis (>70%) to ensure sufficient blood flow to the STA. STA-MCA double anastomoses were performed more than 1 month after the CEA. Postoperative cerebrovascular complications and carotid restenosis were investigated.

RESULTS

All patients in the present series had an excellent postoperative course without cerebrovascular complications during either the CEA or STA-MCA anastomosis phase. Furthermore, no postoperative carotid restenosis occurred, and all STA-MCA anastomoses were patent during a mean follow-up period of 35.6 months.

CONCLUSION

The present study suggests that surgical management by external CEA followed by STA-MCA anastomosis is safe and effective for patients with internal carotid artery occlusion and advanced stenosis of the ipsilateral ECA.