✓ Two autopsy cases of angiographically determined fusiform aneurysms of the vertebral arteries (VAs) are reported and the appropriate literature is reviewed to investigate the pathological characteristics of both fusiform and dissecting VA aneurysms and the pathogenesis of dissecting aneurysms. One patient had suffered a subarachnoid hemorrhage (SAH) due to dissection of a previously documented incidental fusiform aneurysm. The other patient had harbored incidental fusiform aneurysms coexistent with a ruptured aneurysm of the posterior inferior cerebellar artery. The location and pathological features of the aneurysms were similar in the two cases. The aneurysms in both cases displayed intimal thickening, disruption of the internal elastic lamina, and degeneration of the media. A mural hemorrhage and patchy calcification were also found in the case that included SAH. Based on their pathological investigation of these two cases and a review of reported cases, the authors propose that incidental fusiform aneurysms in the VAs are characterized by weakness in the internal elastic lamina and, therefore, have the potential to become dissecting aneurysms, resulting in a fatal prognosis. This suggests that long-term control of blood pressure is mandatory in patients with incidental fusiform aneurysms in the VAs.
Report of two autopsy cases and a review of the literature
Toshihiro Yasui, Masaki Komiyama, Misao Nishikawa, Hideki Nakajima, Yasutsugu Kobayashi, and Takeshi Inoue
Kuniaki Ogasawara, Keiko Yamadate, Masakazu Kobayashi, Hidehiko Endo, Takeshi Fukuda, Kenji Yoshida, Kazunori Terasaki, Takashi Inoue, and Akira Ogawa
Object. Cognitive impairment occurs in 20 to 30% of patients following carotid endarterectomy (CEA). The purpose of the present study was to determine whether postoperative cerebral hyperperfusion is associated with impairment of cognitive function in patients undergoing that procedure.
Methods. Cerebral blood flow (CBF) was measured using single-photon emission computerized tomography scanning before and immediately after CEA and on the 3rd postoperative day in 92 patients with ipsilateral internal carotid artery stenosis of 70% or greater. Hyperperfusion post-CEA was defined as a 100% increase or greater in CBF compared with preoperative values. Neuropsychological testing was also performed preoperatively and at the 1-, 3-, and 6-month follow-up examinations.
At the 1-month postoperative neuropsychological assessment, 11 patients (12%) displayed evidence of cognitive impairment. In addition, the incidence of postoperative cognitive impairment in patients with post-CEA hyperperfusion (seven [58%] of 12 patients) was significantly higher than that in patients without post-CEA hyperperfusion (four [5%] of 80 patients; p < 0.0001). A logistic regression analysis demonstrated that post-CEA hyperperfusion was the only significant independent predictor of postoperative cognitive impairment. Of the seven patients in whom post-CEA hyperperfusion and cognitive impairment were identified 1 month postoperatively, four (including three patients with hyperperfusion syndrome) remained cognitively impaired at the 3- and 6-month follow-up examinations.
Conclusions. Postoperative cerebral hyperperfusion is associated with impairment of cognitive function in patients undergoing CEA. Furthermore, the development of hyperperfusion syndrome is associated with the persistence of postoperative cognitive impairment.
Masaaki Chazono, Shigeru Soshi, Takeshi Inoue, Yoshikuni Kida, and Chikara Ushiku
The purpose of this study was to evaluate the linear and angular parameters of the vertebral body (VB) required for cervical pedicle screw (CPS) insertion by using multiplanar computerized tomography (CT) reconstructions.
Three hundred fifteen vertebrae from C-3 to C-7 in 63 patients were studied. Pedicle dimensions such as pedicle transverse angle (PTA), pedicle sagittal angle (PSA), and pedicle outer width (POW) were measured on axial CT reconstructions, as were linear parameters including the lateral mass thickness (LMT), the anteroposterior (AP) and mediolateral distances between spinal canal and transverse foramen, and spinal canal longitudinal and transverse diameter. In addition, the correlations between PTA and other parameters were calculated using univariate linear regression analysis.
The overall mean LMT ranged from 10.7 to 12.6 mm. The smallest mean AP spinal canal–transverse foramen distance was found at C-7 (1.1 mm),whereas the largest mean distance was at C-4 (3.1 mm). The smallest mean mediolateral spinal canal–transverse foramen distance was found at C-4 (1.2 mm), whereas the largest mean distance was at C-7 (4.7 mm). There were significant intergroup differences between male and female patients except for PTA and spinal canal longitudinal diameter. The PTA had a direct linear correlation with AP and mediolateral spinal canal–transverse foramen distances. The largest Pearson coefficient was 0.71 between the PTA and AP spinal canal–transverse foramen distance and the inverse one was −0.73 between the PTA and mediolateral spinal canal–transverse foramen distance.
Analysis of the data obtained in this study suggests that not only pedicle dimensions but also linear and angular parameters of the VB can be useful data when inserting a CPS.
Tadahiko Shiozaki, Yoshikazu Nakajima, Mamoru Taneda, Osamu Tasaki, Yoshiaki Inoue, Hitoshi Ikegawa, Asako Matsushima, Hiroshi Tanaka, Takeshi Shimazu, and Hisashi Sugimoto
Object. This study was performed to determine whether moderate hypothermia (31°C) improves clinical outcome in severely head injured patients whose intracranial hypertension cannot be controlled using mild hypothermia (34°C).
Methods. Twenty-two consecutive severely head injured patients who fulfilled the following criteria were included in this study: an intracranial pressure (ICP) that remained higher than 40 mm Hg despite the use of mild hypothermia combined with conventional therapies; and a Glasgow Coma Scale score of 8 or less on admission. After the failure of mild hypothermia in combination with conventional therapies; patients were exposed to moderate hypothermia as quickly as possible. As brain temperature was reduced from 34 to 31°C, the volume of intravenous fluid infusion was increased significantly from 1.9 ± 0.9 to 2.6 ± 1.2 mg/kg/hr (p < 0.01), and the dose of dopamine infusion increased significantly from 4.3 ± 3.1 to 8.2 ± 4.4 µg/kg/min (p < 0.01). Nevertheless, mean arterial blood pressure and heart rate decreased significantly from 97.1 ± 13.1 to 85.1 ± 10.5 mm Hg (p < 0.01) and from 92.2 ± 13.8 to 72.2 ± 14.3 beats/minute at (p < 0.01) at 34 and 31°C, respectively. Arterial base excess was significantly aggravated from −3.3 ± 4 at 34°C to −5.6 ± 5.4 mEq/L (at 31°C; p < 0.05). Likewise, serum potassium concentration, white blood cell counts, and platelet counts at 31°C decreased significantly compared with those at 34°C (p < 0.01).
In 19 (86%) of 22 patients, elevation of ICP could not be prevented using moderate hypothermia. In the remaining three patients, ICP was maintained below 40 mm Hg by inducing moderate hypothermia; however, these three patients died of multiple organ failure. These results clearly indicate that moderate hypothermia induces complications more severe than those induced by mild hypothermia without improving outcomes.
Conclusions. The authors concluded that moderate hypothermia is not effective in improving clinical outcomes in severely head injured patients whose ICP remains higher than 40 mm Hg after treatment with mild hypothermia combined with conventional therapies.
Takehiro Uda, Ichiro Kuki, Takeshi Inoue, Noritsugu Kunihiro, Hiroharu Suzuki, Hiroshi Uda, Toshiyuki Kawashima, Kosuke Nakajo, Yoko Nakanishi, Shinsuke Maruyama, Takashi Shibata, Hiroshi Ogawa, Shin Okazaki, Hisashi Kawawaki, Kenji Ohata, Takeo Goto, and Hiroshi Otsubo
Epileptic spasms (ESs) are classified as focal, generalized, or unknown onset ESs. The classification of ESs and surgery in patients without lesions apparent on MRI is challenging. Total corpus callosotomy (TCC) is a surgical option for diagnosis of the lateralization and possible treatment for ESs. This study investigated phase-amplitude coupling (PAC) of fast activity modulated by slow waves on scalp electroencephalography (EEG) to evaluate the strength of the modulation index (MI) before and after disconnection surgery in children with intractable nonlesional ESs. The authors hypothesize that a decreased MI due to surgery correlates with good seizure outcomes.
The authors studied 10 children with ESs without lesions on MRI who underwent disconnection surgeries. Scalp EEG was obtained before and after surgery. The authors collected 20 epochs of 3 minutes each during non–rapid eye movement sleep. The MI of the gamma (30–70 Hz) amplitude and delta (0.5–4 Hz) phase was obtained in each electrode. MIs for each electrode were averaged in 4 brain areas (left/right, anterior/posterior quadrants) and evaluated to determine the correlation with seizure outcomes.
The median age at first surgery was 2.3 years (range 10 months–9.1 years). Two patients with focal onset ESs underwent anterior quadrant disconnection (AQD). TCC alone was performed in 5 patients with generalized or unknown onset ESs. Two patients achieved seizure freedom. Three patients had residual generalized onset ESs. Disconnection surgeries in addition to TCC consisted of TCC + posterior quadrant disconnection (PQD) (1 patient); TCC + AQD + PQD (1 patient); and TCC + AQD + hemispherotomy (1 patient). Seven patients became seizure free with a mean follow-up period of 28 months (range 5–54 months). After TCC, MIs in 4 quadrants were significantly lower in the 2 seizure-free patients than in the 6 patients with residual ESs (p < 0.001). After all 15 disconnection surgeries in 10 patients, MIs in the 13 target quadrants for each disconnection surgery that resulted in freedom from seizures were significantly lower than in the 26 target quadrants in patients with residual ESs (p < 0.001).
In children with nonlesional ESs, PAC for scalp EEG before and after disconnection surgery may be a surrogate marker for control of ESs. The MI may indicate epileptogenic neuronal modulation of the interhemispheric corpus callosum and intrahemispheric subcortical network for ESs. TCC may be a therapeutic option to disconnect the interhemispheric modulation of epileptic networks.
Toshinori Hasegawa, Takenori Kato, Yoshihisa Kida, Ayaka Sasaki, Yoshiyasu Iwai, Takeshi Kondoh, Takahiko Tsugawa, Manabu Sato, Mitsuya Sato, Osamu Nagano, Kotaro Nakaya, Kiyoshi Nakazaki, Tadashige Kano, Koichi Hasui, Yasushi Nagatomo, Soichiro Yasuda, Akihito Moriki, Toru Serizawa, Seiki Osano, and Akira Inoue
This study aimed to explore the efficacy and safety of stereotactic radiosurgery in patients with jugular foramen schwannomas (JFSs).
This study was a multiinstitutional retrospective analysis of 117 patients with JFSs who were treated with Gamma Knife surgery (GKS) at 18 medical centers of the Japan Leksell Gamma Knife Society. The median age of the patients was 53 years. Fifty-six patients underwent GKS as their initial treatment, while 61 patients had previously undergone resection. At the time of GKS, 46 patients (39%) had hoarseness, 45 (38%) had hearing disturbances, and 43 (36%) had swallowing disturbances. Eighty-five tumors (73%) were solid, and 32 (27%) had cystic components. The median tumor volume was 4.9 cm3, and the median prescription dose administered to the tumor margin was 12 Gy. Five patients were treated with fractionated GKS and maximum and marginal doses of 42 and 21 Gy, respectively, using a 3-fraction schedule.
The median follow-up period was 52 months. The last follow-up images showed partial remission in 62 patients (53%), stable tumors in 42 patients (36%), and tumor progression in 13 patients (11%). The actuarial 3- and 5-year progression-free survival (PFS) rates were 91% and 89%, respectively. The multivariate analysis showed that pre-GKS brainstem edema and dumbbell-shaped tumors significantly affected PFS. During the follow-up period, 20 patients (17%) developed some degree of symptomatic deterioration. This condition was transient in 12 (10%) of these patients and persistent in 8 patients (7%). The cause of the persistent deterioration was tumor progression in 4 patients (3%) and adverse radiation effects in 4 patients (3%), including 2 patients with hearing deterioration, 1 patient with swallowing disturbance, and 1 patient with hearing deterioration and hypoglossal nerve palsy. However, the preexisting hoarseness and swallowing disturbances improved in 66% and 63% of the patients, respectively.
GKS resulted in good tumor control in patients with either primary or residual JFSs. Although some patients experienced some degree of symptomatic deterioration after treatment, persistent adverse radiation effects were seen in only 3% of the entire series at the last follow-up. Lower cranial nerve deficits were extremely rare adverse radiation effects, and preexisting hoarseness and swallowing disturbances improved in two-thirds of patients. These results indicated that GKS was a safe and reasonable alternative to surgical resection in selected patients with JFSs.
Toru Serizawa, Yoshinori Higuchi, Masaaki Yamamoto, Shigeo Matsunaga, Osamu Nagano, Yasunori Sato, Kyoko Aoyagi, Shoji Yomo, Takao Koiso, Toshinori Hasegawa, Kiyoshi Nakazaki, Akihito Moriki, Takeshi Kondoh, Yasushi Nagatomo, Hisayo Okamoto, Yukihiko Kohda, Hideya Kawai, Satoka Shidoh, Toru Shibazaki, Shinji Onoue, Hiroyuki Kenai, Akira Inoue, and Hisae Mori
In order to obtain better local tumor control for large (i.e., > 3 cm in diameter or > 10 cm3 in volume) brain metastases (BMs), 3-stage and 2-stage Gamma Knife surgery (GKS) procedures, rather than a palliative dose of stereotactic radiosurgery, have been proposed. Here, authors conducted a retrospective multi-institutional study to compare treatment results between 3-stage and 2-stage GKS for large BMs.
This retrospective multi-institutional study involved 335 patients from 19 Gamma Knife facilities in Japan. Major inclusion criteria were 1) newly diagnosed BMs, 2) largest tumor volume of 10.0–33.5 cm3, 3) cumulative intracranial tumor volume ≤ 50 cm3, 4) no leptomeningeal dissemination, 5) no more than 10 tumors, and 6) Karnofsky Performance Status 70% or better. Prescription doses were restricted to between 9.0 and 11.0 Gy in 3-stage GKS and between 11.8 and 14.2 Gy in 2-stage GKS. The total treatment interval had to be within 6 weeks, with at least 12 days between procedures. There were 114 cases in the 3-stage group and 221 in the 2-stage group. Because of the disproportion in patient numbers and the pre-GKS clinical factors between these two GKS groups, a case-matched study was performed using the propensity score matching method. Ultimately, 212 patients (106 from each group) were selected for the case-matched study. Overall survival, tumor progression, neurological death, and radiation-related adverse events were analyzed.
In the case-matched cohort, post-GKS median survival time tended to be longer in the 3-stage group (15.9 months) than in the 2-stage group (11.7 months), but the difference was not statistically significant (p = 0.65). The cumulative incidences of tumor progression (21.6% vs 16.7% at 1 year, p = 0.31), neurological death (5.1% vs 6.0% at 1 year, p = 0.58), or serious radiation-related adverse events (3.0% vs 4.0% at 1 year, p = 0.49) did not differ significantly.
This retrospective multi-institutional study showed no differences between 3-stage and 2-stage GKS in terms of overall survival, tumor progression, neurological death, and radiation-related adverse events. Both 3-stage and 2-stage GKS performed according to the aforementioned protocols are good treatment options in selected patients with large BMs.