[Study on photographing experiment of infrared detector].

Infrared detectors are widely used in multi spectral remote sensing systems, and in order to verify photographing principles of infrared time delay integration (TDI) detector, and make preparations for future research, a verification system for infrared TDI camera is proposed in the present paper. Experimental methods are explained thoroughly and two major factors which affect image quality are analyzed. First, the causes of image motion and their effects on the quality of image are studied, and a novel architecture using high precision DC-speed machine is presented, then the relationship between velocity of precision turntable and detectors line transfer frequency is determined by Kalman algorithm. Second, four focusing means are analyzed and compared, and video signal amplitude method is selected according to practical application. Finally, a genuine demo system is established in national supervision and test center for optics mechanics quality. 5.3, 6.4 and 9.2 mm drones are chosen for testing. Experimental results indicate that the obtained drone is vivid, and camera's resolution achieves 11.3 lines per mm, which satisfies preliminary aims.

[High speed transmission system for dual-spectral remote sensing system].

In order to realize dual-spectral aerial camera image data transmission, a novel optical transmission system is proposed, then transmission scheme, structure of data frame and timing recovery method are discussed thoroughly. First, valid data in one line are picked up from two detectors before transmitting, a timing recovery method which makes in-out data timing and format consistent, is proposed using line valid interrupt flag. Second, based on transmitting and receiving buffering mechanism, dual asynchronous detectors data are transmitted in a single fiber. Third, transmitting and receiving systems are implemented using large programmable devices which embeds high speed data interface. Finally, behavioral and system verification method is proposed as well. Experimental results indicate that the system could support full, median and base cameral link protocol, serial data transmitting speed could be 6.25 Gb x s(-1), and pixel data rate is 40 MHz at most for two detectors. It is very suitable for space and serial remote sensing equipment due to its compact and high reliable structure.

[Minimal invasive neurosurgical treatment of intervertebral foraminal lesions].

OBJECTIVE: To investigate the effectiveness of minimal invasive neurosurgery in treatment of intervertebral foraminal lesions. METHOD: Fifty-six patients with intervertebral foraminal lesions were divided into 2 groups: minimal invasive neurosurgery group (MG group, n=31) and traditional neurosurgery group (TG group, n=25). Their pre-operational clinical conditions, methods of surgery, duration and effectiveness of operation were analyzed retrospectively. Follow-up was conducted for 3-48 months. RESULTS: Twenty-three of the 25 patients in the TG group (92%) had their lesions resected completely and 2 of the 31 patients (8%) underwent subtotal resection. In the MG group 28 of the 31 patients (90.32%) had their lesions resected completely, 2 (6.45%) underwent subtotal resection, and 1 patient (3.23%) showed epidural remains and did not receive further treatment. There was no significant difference in the effective rate between these 2 groups. The operation time of the TG group was (188 +/- 35) minutes, significantly longer than that of the MG group [(140 +/- 26) minutes, P < 0.01]. Follow-up showed that all patients resumed their normal life except the patient with epidural remains in the MG group, and no recurrent patient was found. CONCLUSION: The minimal invasive neurosurgery is convenient, effective, and cheaper to treat intervertebral foraminal lesions. However, precise localization and intimate knowledge of the anatomy are important.

[Multianalysis of short-term prognostic factors in surgical practices for hypertensive intracerebral hemorrhage].

OBJECTIVE: To evaluate and compare the effectiveness of different types of surgical therapy for patients with hypertensive cerebral hemorrhage, and analyze the major risk factors of prognosis. METHODS: 2464 patients with hypertensive cerebral hemorrhage in 92 hospitals in different areas of China underwent different types of surgical treatment: Group I (n = 639), undergoing traditional craniotomy as control; Group II (n = 409), receiving minimally invasive hematoma evacuation; and Group III (n = 1416), receiving CT guided stereotaxic hematoma aspiration. The clinical data were collected and underwent multianalysis. RESULTS: The factors influencing the short-term prognosis were Glasgow coma scale (GCS) score before surgery and the incidence of postoperative complications in Group II; GCS score before surgery and the incidence of postoperative complications and volume of hemorrhage, duration between ictus and surgery, use of urokinase in Group III; and GCS score before surgery, muscle power before surgery, diastolic pressure at admission and postoperative complications in Group III. CONCLUSION: Analysis of prognosis related factors of cerebral hemorrhage plays a very important role in the selection of therapeutic strategy. It may be beneficial for standardizing surgical indications, further designing large scale clinical trial, helping the doctors select appropriate strategy of treatment, and serving the social population better.

[The efficacy of three different approaches in treatment of hypertensive intracerebral hemorrhage: a multi-center single-blind study of 2464 patients].

OBJECTIVE: To compare the efficacy and indications of the 3 approaches: conventional open craniotomy (COC), computed-tomography guided aspiration (CTGA), and key-hole approach (KHA) in neurosurgical management for hypertensive intracerebral hemorrhage (HICH). METHODS: The clinical data of HICH 2464 patients, aged 14 - 75, operated on within 24 hours after stroke, with a Glasgow coma score >or= 5, hospitalized in 135 hospitals all over the mainland of China, were collected and underwent single-blind study. RESULTS: Among the 2464 patients 639 underwent COC, 1416 underwent CTGA, and 409 were operated on via KHA. The overall mortality rates within one and three months after operation were 19.3% and 21.1% respectively. The mortality rate within 3 months after operation (M3m) of the patient with a GCS or= 8. The M3m of the patients with complications was 4.4 times as much as that of the patients without complications. The M3m of the patients with hemorrhage in thalamus was 2.4 times as much as that of the patients with cortical hemorrhage. The M3m of the COC group was 24.6%, higher than those of the KHA group (17.6%) and CTGA group (20,6%). The postoperative complication rate of the COC group was 29.9%, significantly higher than that of the CTGA group (24.8%, P = 0.015). There were no significant differences in postoperative complication rate between the COC and KHA groups and between the CTGA and KHA groups (both P > 0.05). CONCLUSION: KHA and CTGA are both better than COC in treatment of HICH with more favorable outcome and less postoperative mortality and morbidity.

[Application of computer-assistant neuronavigation in spinal operation].

OBJECTIVE: To discuss the efficacy, accuracy, and safety of computer-assistant neuronavigation in operation of vertebrae and spinal cord. METHODS: The data of computer-assistant neuronavigation used in the operation for 41 cases, including 9 cases of neurinoma, 10 cases of ependymoma, 5 cases of angioreticuloma, 7 cases of spinal meningioma, 4 cases of astrocytoma, and 1 case of cysticercosis, and 1 case of osteoblastoma. from March 2001 to December 2003 were reviewed. RESULTS: Twenty-six screws were fixed in 4 patients. Total removal was succeeded in 33 of the 37 cases of 37 spinal tumors and all patients survived after operation. CONCLUSION: Image-guided navigation for spinal surgery is able to save time and reduce operational lesion. More importantly, it improves neurosurgeon's comprehension of spinal anatomy.

[Application of the neuro-endoscope to the intracranial aneurismal surgery].

OBJECTIVE: To study the role of neuro-endoscope in the intracranial aneurismal surgery, analyzing its benefits, and disadvantages. METHODS: Endoscopy was used as an adjunct in the microsurgical treatment of clipping aneurysms on 88 patients with 89 aneurysms, of which 82 aneurysms in 81 patients were located in the anterior circulation and 7 were located in the posterior circulation. Keyhole approach was performed on all patients, and micro-Doppler ultrasound technique was used before and after clipping. In 84 aneurysms, endoscope-assisted microneurosurgery (EAM) was used in addition to microsurgical dissection and clipping so as to observe the neck anatomic features and perforators and to verify the optimal clipping position. Endoscope-controlled microneurosurgery was used for 5 aneurysms to observe the anatomy around aneurysm, such as the posterior communicating artery and the opposite anterior communicating artery behind the internal carotid artery. RESULTS: Postoperative angiography performed on 86 patients showed satisfactory aneurysm clipping. Operative mortality was 0. There were 7 cases of postoperative complications, with an incidence rate of 7.95%, and none case was directly related to endoscopy. CONCLUSION: Improving observation of regional anatomy because of its ability in magnification, illumination, and looking around dead angle, neuro-endoscopy is very useful for complex aneurysms.