Chronic subdural hematoma(CDH) is collection of encapsulated ligified hematoma in subdural space and familiar with neurosurgens. 50 patients of CDH were treated using burr holes and closed-system drainage. The study is a retrospective clinical analysis and reviewed of the surgical method.

Between 1995 and 2001, 50 patients with CDH had surgical treatments, using burr holes and closed-system drainage technique at the department of neurosurgery, Ewha Uninversity Medical Center, Mok-Dong hospital. Mean age was 61 years with a range 35-82 years. The male/female ratio is 41/9. Diagnosis of CDH was confirmed by CT scans. The author divided into 2 groups ; traumatic group and atraumatic group. Retrospectively the author analysed the clinical data regarding age group, sex ratiso, etiology, neurologic grade at admission, post-operative outcomes and outcomes according to neurologic grade at admission. These clinical data compared the traumatic group with atraumatic group.

The number of patients were 27 in traumatic group and 23 in atraumatic groups. The mean age in traumatic and atraumatic groups was 60 years respectively. These lesions generally occur in elderly with the average 61 years. The male/female ratio 21/6 in traumatic group and 20/3 in atraumatic group. Generally it was predominent in male patients. The causes in atraumatic group were hypertension(2 patients), CVA(3 patients) and the others remain unknown. The neurologic grade at admission ; 0 grade 26(male/female=21/5, 1 grade) 7(m/f=6/1), 2 grade 14(m/f=11/3). The outcome scale according to glasgow scale ; 5 scale 31(m/f=24/7), 4 scale 15(m/f=13/2) and 3 scale 4(m/f=4/0). The outcome scale according to neurologic grade at admission was that the more neurologic grade is good, the more outcome is better.

The burr holed and closed system drainage technique is simple, mininal risk, and results in good recovery with short days of admision. This technique is considered as first choice for the evacuation of hematoma of CDH.

Chronic hydrocephalus is a frequent occurrence after aneurysmal subarachnoid hemorrhage. 14 patients with chronic hydrocephalus and treating with shunting procedure were retrospectively reviewed. Chronic hydrocephalus after aneurysmal subarachnoid hemorrhage was usually recognized when gradual deterioratsm of consciousnes, unexplanied aggrvation of occuring neurologic defists, especially urinary incontinence.

Two-hundred consecutive patients with aneurysmal SAH were admitted to the neuro-surgical department Ewha Womans university Mok-Dong Hospital between fanuary 1994 and fanuary 2001, in all the patients aneurysms clipping was carried out. Among then 14 patient to chronic hydrocephalus following aneurysmal SAH and treating with shunting procedure were reviewed according to consionsnes level(Hunt-Hess classification), amonts of SAH(grading system of Fisher), sites and incidence. The chronic hydrocephalus was diagnosed CT findings in the clinical findings ; deterioration of level of consiousness, aggravation of neurologic deficits and urinary incontinence.

The average age of patients was 51 and predominant in women(man : woman=4 : 10). The incidence of chronic hydrocephalus was 7% and the aneurysmal sites were followings : posterior communicating artery(7), anterior communicating artery(4), and internal carotid artery bifuncation, middle cerebral artery and superior cerebellar artery were 1 respectiviy. According Hunt-Hess Grades were following ; grade I, II, III and IV=1, 6, 3 and 4. The number of patients according to Fisher's grading system were following ; grade 2, 3, and 4=6, 7, and 1. The outcomes by Glasgow assessment were the followings ; Score 5 and 4=9 and 5.

The response to shunting procedure in symptomatic patients of Chronic hydrocephalus following aneurysmal SAH. good in all patients.

Lumbar disc herniations at the L1-L2, L2-L3, and L3-L4 level are rare. The purpose of this study is to observe the variable clinical finding of upper lumbar disc herniations and to provide proper treatment modality.

Between 1998 Jan. and 1999 Dec., seventeen patients with upper lumbar disc herniations who were undergone surgery in our institute were retrospectively evaluated. Patients were evaluated based on following factors : age, sex, aggravating factor, symptoms and signs type of disc herniation, type of surgery, and outcome of post-surgery.

The incidence of lumbar disc herniation at the level of L1-2, L2-3 and L3-4 is 6.1% with declining frequency as the level ascends. The peak age incidence is 6th decade in both sex. Preoperative symptomes and signs are variabe. In sixteen cases, posterior approach was done. In these cases, twelve cases were performed microscopic partial hemilaminectomy, and four cases with spinal stenosis were performed total laminectomy and posterior screw fixation with bone fusion. In one case, lateral extracavitary approach was done. In results of operation, fourteen cases showed more than good grade(82%).

The age incidence of lumbar disc herniations at the level of L1-2, L2-3 and L3-4 older than lumbar disc herniations at the lower level of L4-5 and L5-S1. The signs and symptoms are variable. In our cases, most of the patients were performed posterior approach with microscopic partial hemilaminectomy except the patients combined spinal stenosis. One case was performed a lateral extracavitary approach because the risk of the cord and cauda equina injuries. The prognosis of upper lumbar disc herniations after treatment with only microscopic partial hemilaminectomy and diskectomy is comparable with the prognosis of lumbar disc herniations at the lower level.

Despite of recent advances in pharmacological treatment and improvement surgical and anesthetic techniques, subarachnoid hemorrhage(SHA) from ruptured intracranial aneurysms with poor clinical grades still carries unacceptably high morbidity and mortality rates. Recently surgery for aneurysmal SAH with poor clinical grade has increased interest.

The authors experienced 57 patients with poor clinical grade (Hunt and Hess grade IV-V) after ancurysmal SAH. Among them 25 patients were treated with immediate CSF drainage via ventriculostomy, blood pressure control, early angiography(except 3 patients) and surgery within 12 hour of admission.

The outcomes of patients were categorized using a four-tiered scale :

1) independent and working

2) impaired but independent

3) severly impaired and dependent

4) dead

The average age was 48(13-75) and the male to female ratio was 7:18 in surgical group. The average time to admission and surgery was 12 hours or less among the 25 patients. Among them 9 cases were dead, 2 cases were severly impaired and dependent, 3 cases were impaired but dependent, and 11 cases were independent and working. In this patient all cases, exception one could be ligated with a clip.

The above results suggest that the acute aggressive surgery based on appropriate selection in poor aneurysmal SAH patients can reduce of the mortality.

Arterovenous malformations(AVVMs) represent the most commonly encountered symptomatic vascular malformations in the field of vascular neurosurgery. Surgically accessible AVMs that present with hemorrhage should be removed to reduce the risk of subsequent hemorrhage. The advance of surgery is based on the size, location and pattern of venous drainage and these anatomic features influence the treatment risk. The author studied the above features for predictor of the surgical resection of AVMs.

Nineteen patients(8 male and 11 female patients) with intracranial AVMs were treated at the Ewha Womans Medical Center between March 1989 and Dec. 1996. The mean age, and sexual ratio, of the pts as will as symptoms, location, feeding arteries, pattern of venous drainage and size of the nidus were studied. AVMs were graded according to the Spetzler and martin grade system. Overall outcome and postoperative results in eighteen patients were evaluated according to Glasgow Outcome SCale(GOS).

The average age at the time of treatment was 30.8 years old(range 4-55 years old). The hemorrhage was the most common symptom, occurring in 15(80%) patients, and 2(10%) patients presented with headache, 195%) patient with seizure, 1(5%) patient with neurological deficit. The feeding arteries were as the followings ; middle cerebral artery 8(42%), anterior cerebral artery 2(10%), posterior cerebral artery 1(5%), The pattern of draining veins were described into superficial and deep ; superficial 9(47%), deep 10(53%), The size of the nidus were as the followings ; small(<3cm) 9(47.5%), medium(3-6cm) 9(47.5%), large(>6cm) 1(5%), The Spetzler-Martin's grade and the outcome according to the grade were as follows ; grade I;3(17%) resulted GOS-5 3 patients, grade II ;5(26%) did GOS-5 6 patients, grade III; 5(26%) did GOS-5 4 patients and GOS-4 1 patient, grade IV;4(21%) did GOS-5 3 patients and GOS-4 1 patient, grade V;1(5%0 did GOS-1 1 patient. Overall, there were no death in surgical treatment, patients, the morbidity value was 2(10%) patients, the remainder were completely cured.

The Spetzler-Martin grade I-IV AVMs were associated with low rates of surgical morbidity and mortality, Therefore, surgery is the best treatment in the these grades.

Tumors of the basal posterior fossa, especially the clivus or petrous apex area, are embarrasing lesions because surgical access to these areas remains a formidable challenge.

Numerous approaches for lesions at this deep-seated and vital location, have been utiliged, but disappointed in resuts. The author consider that the petrosal approach is the most suitable for tumors located at these areas. The surgical technique of this approach is described and reviewed its advantages.

The author review the 14 harboring benign nature via the petrosal approach form September 1992 to February 1994.

There was no mortalily in this series. Total removal was achieved in 8 patients. Morbidity included hemiparsis(4 patients), cerebeller sings(3 patients), 7th cranial nerve deficit(1 patient) and persistent CSF leakage(1 patient).

The petrosal approach for the following advantages : the cerebellum and temporal lobes are minimally retracted, the operative distance to the clivus is shortened, the surgeon has a direct line of sight to the lesion and the anterior and lateral aspects of the brain stem, the neural and otological structures including the cochlea, the labyrinth and the facial nerves are preserved, the transveres and sigmoid sinuses as well as the vein of Labbe and the basal occipital veins are preserved, the tumour's blood supply is intercepted early in the procedure, multiple axes for dissection are provided, and dissection is performed along alongitudinal axis.

It is suggested that the petrosal approach is the most suitable for tumors of the basal posterior fossa(at the petrous apex or clivus).

The timing of aneurysm surgery has been a topic of major neurosurgical controversy.

Aneurysmal rebleeding is the most cataclysmic and disabling event following initial subarachnoid hemorrhage. Thus, early surgical obliteration of aneurysm eliminates the potential for rebleeding during the highest risk period.

The results of operation for the twenty-three patients who had admitted to neurosurgical departments, Mokdong hospital and undergone surgery within the 24-72 hours after initial rupture of these aneurysms from October, 1993 to August, 1996, were reviewed.

Twenty-three patients underwent craniotomy for clipping and intracranial clot evacuation, and postoperative hypertensive, hypervolemic, and hemodilution therapy. The outcome was excellent in 10(43%), good in 3(13%), poor in 5(22%) and death in 5(22%). The mean age was 57.7 and the ratio of male to female was 13:10. The outcome according to Hunt-Hess(H-H) grade was followings. H-H grade 1 was 2(%) and all excellent outcome, H-H grade 2 24(61%) and the outcome were excellent in 8(35%), good in 1(4%), poor in 2(9%), death in 3(13%), H-H grade 3 was 6(26%) and good in 2(9%), poor in 2(9%), death in 2(9%), and H-H grade 4 was 1(4%) and the outcome was poor in 1(4%). The outcome according to grading system of Fisher was followings. Grade 2 was 6(26%), and the outcome was excellent in 5(22%) and death in 1(4%). The grade 3 was 14(61%) and excellent in 5(22%), good in 2(9%), poor in 3(13%), and death in 1(4%). The grade 4 was 3(31%) and good in (4%) and poor in 2(9%). The variations in anterior communicating complex were followings. The both A₁ equal in 6(26%), left A₁ dominancy was 1(4%), right A₁ atresia was 13(57%) and left atresia was 3(13%).

The most favorable outcomes and lowest mortality rate were patients of H-H grade 1 group. The surgical results of alert patients with early surgery should even further improve as compared to delay surgery. However, patients who present in poor medical condition at the time of operation were still indicated delay surgery.