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Liang-fu Zhou

Publications and source records attributed to Liang-fu Zhou.

At least 19 recordsLinked to original sources
PubMed2006

Keyhole approach surgery for petroclival meningioma.

BACKGROUND: In China, the feasibility of keyhole approach in surgical treatment of petroclival meningioma has not been well evaluated. This report summarized our experience in 25 patients with petroclival meningioma who had been treated with keyhole approach surgery. METHODS: From July 2000 to July 2005, 25 patients with petroclival meningioma were subjected to resection via subtemporal, retrosigmoid or combined keyhole approaches. The extent of tumor resection was evaluated by MRI 3 months after surgery, and postoperative complications were investigated. RESULTS: The maximum diameter of tumors ranged from 2 to 7 cm (mean, 4.5 cm). Gross total resection (GTR) was achieved in 14 patients, giving a GTR rate of 56%. Subtotal resection (STR) was carried out in 8 patients and partial resection in 3. Thirteen patients kept normal neurological status, whereas others suffered from cranial nerve deficits (VII, VII, III and lower CN). One patient died in the postoperative period. CONCLUSIONS: Keyhole approach surgery, especially the combined keyhole approach is suitable for the treatment of petroclival meningioma. It provides easy and quick access to the supra- and infratentorial juxta-clival region without drilling of the petrous bone. Complications related to the approach can be minimized.

Adult↗
PubMed2006

[Early-mid-phase microsurgery for ruptured cerebral anterior circulating aneurysm].

OBJECTIVE: To evaluate clinical strategy and effect of early-mid-phase microsurgery for ruptured cerebral anterior circulating aneurysm. METHODS: Seventy-five patients presenting with anterior circulating aneurysmal subarachnoid hemorrhage (SAH) underwent early-mid-phase (within 3 days or 3-10 days) microsurgical clipping at Huashan Hospital between January 2001 and August 2004. Glasgow outcome scale (GOS) was conducted to evaluate patients' outcomes. RESULTS: Of 81 intracranial aneurysms, 77 lesions were clipped successfully, and 4 were wrapped. Good outcome was achieved in 53 cases, mild disability in 9 cases, severe disability in 7 cases, persistent vegetative state in 3 cases, and 3 patients (4%) died after surgery. The difference of GOS was statistically significant between patients in Hunt and Hess Grade I-III and Grade IV-V. However, there was no significant difference between early surgery and metaphase surgery. CONCLUSIONS: Early-mid-phase microsurgery for ruptured cerebral anterior circulating aneurysm is considered the feasible opinion.

Acute Disease↗
PubMed2005

[High risk factors of upper gastrointestinal bleeding after neurosurgical procedures].

OBJECTIVE: To analyze high risk factors of postoperative upper gastrointestinal (GI) bleeding after neurosurgery so as to give guidance for prevention of GI bleeding. METHODS: A questionnaire was developed to investigate the medical records of 1500 patients who were hospitalized and underwent neurosurgical operations in 1997. Logistic regression analysis was made. RESULTS: 1430 valid questionnaires were obtained. Postoperative upper GI bleeding occurred in 75 patients (5.24%). The incidence of upper GI bleeding were 6.64% (54/813) in the male patients and 3.40% (21/617) in the female persons (P = 0.007); 9.88% (41/415) in those aged > 50 and 3.35% in those aged < or = 50 (P = 0.001). Glasgow Coma Score less than 10 pre- and post-operation, the incidence of upper GI bleeding was more than 17.5% (14/80, pre-operation GCS 7-10) and 20.9% (14/67, pre-operation GCS 3-6), and 20.25% (16/79, first day of post-operation GCS 7-10) and 23.75% (19/80, first day of post-operation GCS 3-6). The incidence of upper GI bleeding of the patients with intracerebral hematoma, intraventricular hemorrhage, subdural hematoma, and extradural hematoma were 15.7%, 10.0%, 6.00%, and 2.94% respectively (P = 0.02). The incidence of upper GI bleeding of the patients with tumors of fourth ventricle of cerebrum, brainstem, cerebral hemisphere, and sellar hypothalamus were 15.79% (3/19), 7.89%, 5.71%, and 3.74% respectively. In the emergent cases, the incidence of upper GI bleeding was higher in those with hypertension. The incidence of upper GI bleeding was 5.46% in the patients undergoing adrenocortical hormone treatment, significantly higher than that in those who did not receive such treatment (2.13%). CONCLUSION: Patients who are at high risk of developing postoperative upper GI bleeding including that: age greater than 50 years; male; Glasgow Coma Score less than 10 pre and post operation; The lesion was located in brain stem and forth ventricle; Hypertensive cerebral hemorrhage; Intracerebral and intraventricular hemorrhagic brain trauma; Postoperative pneumonia, brain edema, encephalic high pressure, pyogenic infection of the central nervous system and other postoperative complications. The mortality of patients with postoperative upper GI bleeding was evidently higher than that of the patients without postoperative upper GI bleeding.

Age Distribution↗
PubMed2005

[Prospective comparison of functional magnetic resonance imaging and intraoperative motor evoked potential monitoring for cortical mapping of primary motor areas].

OBJECTIVE: To compare the relation between the preoperative functional magnetic resonance imaging (fMRI) with blood oxygen level dependent (BOLD) technique and intraoperative motor evoked potential (MEP) monitoring for cortical mapping of primary motor cortex in patients with tumors near the central area. And to determine whether non-invasive preoperative fMRI can provide results equivalent to those achieved with the invasive neurosurgical "gold standard". METHODS: A prospective study of 16 patients with various pathological tumors of the central area was conducted. Preoperative fMRI scans using the BOLD contrast technique in each patient were performed. An activation scan was achieved by using a motor task paradigm, which consisted of simple flexion-extension finger movements and finger-to-thumb touching in a repeating pattern. The anatomical structure was delineated by the T(1)-weighted three-dimensional fast spoiled gradient recalled sequence (3D/FSPGR) immediately afterward. The BOLD images were overlaid on the T(1)-weighted 3D/FSPGR images, and then co-registered to the neuronavigation system. The fMRI activations were documented by using a neuronavigation system in sequence, and compared to standardized intraoperative MEP monitoring, which included direct cortical electrical stimulation (DCES) or transcranial cortical electrical stimulation (TCES) or their combination. The compound muscle action potentials of forearm flexor and hand muscle responses were recorded during either TCES or DCES. Two techniques were compared to determine the accuracy for cortical mapping of primary motor areas with fMRI. RESULTS: Overall, the intraoperative MEP monitoring showed good correlation with fMRI activation in 92.3% of cases. The coincidence rate, however, was 100.0% between TCES and fMRI, and 66.7% between DCES and fMRI respectively. There was no statistically difference between two cortical mapping techniques, chi-square test of paired comparison of enumeration data, P < 0.01. CONCLUSION: BOLD fMRI was a high sensitive and reliable technique to locate the position of the primary motor areas and their spatial relation with adjacent tumor, especially for the presurgical planning in patients with central area brain tumor.

Adolescent↗
PubMed2005

[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.

Adolescent↗
PubMed2005

[Application and reliability of balloon occlusion test in treatment of cerebrovascular diseases].

OBJECTIVE: To study the reliability of applying balloon occlusion test (BOT) to evaluate the compensation capacity of cerebral collateral circulation, and investigate the validity of different criterion about BOT and techniques to improve the security of BOT. METHODS: A retrospective analysis was conducted on the results of 86 patients, 39 males and 47 females, aged 49.8 (13 - 72), 67 suffering from intracranial aneurysm and 19 from traumatic carotid cavernous fistula, who received BOT, and on the results of 38 of the 66 patients who accepted artery occlusion after the BOT. RESULTS: The positive rate of diagnosis was 10.47% and the negative rate was 89.53% by conventional BOT; whereas the positive rate of diagnosis was 36.05% and the negative rate was 63.95% with combined cross circulation and conventional test. The brain ischemia rate after cerebral artery occlusion therapy was 8.33%. The BOT-related complication rate was 3.49%. CONCLUSION: (1) The current BOT technique can basically provide reliable results. (2) The cross circulation test and hypotensive provocative test can effectively improve the specificity of BOT. (3) More perfect BOT criterion for the prediction of cerebral tolerance is still to be worked out. Combination of the conventional method and advanced imaging technique and search for an objective and quantificational criterion would be of reward.

Adolescent↗
PubMed2005

[Microsurgical treatment of nonmeningeal tumors of the cavernous sinus].

OBJECTIVE: To analyze the differential diagnosis of and effectiveness of surgical treatment on nonmeningeal tumors of cavernous sinus. METHODS: The clinical data, including clinical manifestations, diagnosis and differential diagnosis, operative procedure, and treatment results of 67 cases of nonmeningeal tumors of cavernous sinus, 32 males and 35 females, aged 41 +/- 16, who underwent microsurgical treatment were analyzed respectively. RESULTS: The main clinical presentation included cranial nerve paralysis (47 cases, 70.1%), neuroendocrine symptoms (11 cases, 16.4%), eye pain (9 cases, 13.6%), proptosis (7 cases, 10.6%), limb weakness (5 cases, 7.5%), headache, dizziness, lethargy, and temporal lobe epilepsy (4 cases each), and epistaxis (1 case). All patients had CT and/or MRI scanning before operation. Twenty-six patients had DSA examination and balloon occlusion test (BOT). All patients underwent orbito-zygomatico-pterional craniotomy. Twenty cases were operated on via intradural approach, 33 cases via epidural approach, and 14 cases via epidural/intradural combination approach most of which suffered from invasive pituitary adenoma and dumbbell type trigeminal neurinoma. Pathological examination revealed that hemangioma (24 cases), trigeminal schwannoma (18 cases), and invasive pituitary adenomas (11 cases) comprised the majority of tumors; the remaining tumor types were chordoma, chondroma, chondromyosarcoma, chondrofibroma, dermoid tumor, malignant nerve sheath tumor, metastatic tumor, and lymphoma. In the intradural approach group, total tumor removal was achieved in 8 cases (40%), and 7 (35%) cases and 5 (25%) cases had subtotal and partial resection respectively. In the epidural approach group, 27 cases (81.8%) had total tumor removal, while 1 case (3.0%) had subtotal and 5 cases had partial excision of the tumor. In the epiduro-transdural approach group 10 cases (71.4%) achieved total resection and 4 cases (28.6%) had subtotal resection. Postoperative follow-up lasting 6 months to 10 years showed that the pre-operative central nervous system symptoms recovered in 39 cases (58.2%). The aggressive or new symptoms mainly included paralysis of oculomotor nerve (13 cases, 19.4%), trigeminal nerve (9 cases, 13.4%), and abduct nerve (9 cases, 13.4%). CONCLUSION: Depending on pathologic type and growth pattern of the tumor, extended middle skull base epidural or epidural-transdural approach is selected. Such techniques can offer satisfactory outcome, protecting the cranial nerve functions and removing the tumor to the maximum extent.

Adolescent↗
PubMed2005

[Gamma knife radiosurgery for large trigeminal schwannomas].

OBJECTIVE: To evaluate the role of gamma knife (GK) radiosurgery in controlling large trigeminal schwannoma. METHODS: The clinical data of 30 patients suffering from large trigeminal schwannoma with a maximum diameter of 39.0 mm (31.0 to 53.0 mm), who underwent GK radiosurgery, used as the primary treatment modality in 20 patients and used to cure the residuals of tumor after microsurgery in 10 patients, with the maximum irradiation dose to tumor of 25.8 Gy (20.0 to 33.0 Gy) and a tumor margin dose of 12.2 Gy (9.0 to 14.0 Gy), were analyzed respectively. RESULTS: The 30 patients had been followed up for 78 months (24 to 136 months). Twenty-nine of the 30 patients were alive, and one patient with malignant trigeminal schwannoma died of tumor progression 36 months after the GK radiosurgery. Neurological deficits were improved in 24 patients and 3 patients' condition remained stable. Two patients' symptoms worsened 5 and 30 months after the GK radiosurgery respectively because of tumor swelling and tumor cyst enlarging. Then these two patients underwent microsurgery and their tumors were subtotally removed. Disappearance of tumor occurred in 4 patients, a marked decrease in tumor volume was observed in 20 patients, three tumors kept unchanged or slightly regressed in volume, and 3 tumors, including that of the patient who died, progressed. The tumor-growth control rate was 90% (27/30). Two patients underwent craniotomy after GK radiosurgery and one of these 2 resected specimens underwent histopathological examination. The histopathological findings of this tumor resected 30 months after GK radiosurgery revealed that most of the tumor tissue necrosed and was full of microcysts, the residual tumor cells in peripheral areas underwent hyaline degeneration, and the nuclei showed pyknosis. CONCLUSION: GK may be a good alternative treatment for selective patients suffering from large trigeminal schwannoma with a maximum diameter <or= 40 mm.

Adult↗
PubMed2005

[Diagnosis and treatment of tentorial dural arteriovenous fistulae].

OBJECTIVE: Tentorial dural arteriovenous fistulae are uncommon but life-threatened lesions. We present our experience of 5 cases with tentorial dural arteriovenous fistulae, review the relevant literature and present the rationale of our current management strategy. METHODS: The data of five patients with tentorial DAVF treated in Huashan Hospital between June 2002 and May 2003 were reviewed retrospectively, including their ill history, neuroimagings, operation records and follow-up data. RESULTS: There were 3 females and 2 males with age from 25 to 52 years (average, 42.6 years). Clinical manifestations were acute subarachnoid hemorrhage in 2 cases, progressing neurological deficits in 3 cases. MRI and DSA were major diagnostic and follow-up modalities. Borden classification type II was in 1 case, type III in 4 cases. According to DAVF location, tentorial marginal type were in 3 cases, tentorial lateral type 1 case, tentorial medial type 1 case. Two patients had transarterial embolization preoperatively. All patients underwent craniotomy with the coagulation of the nidus and tentorium, disconnection of leptomeningeal venous drainage. The surgical approaches were via trans-anterior-petrous approach in 3 cases, transpterional subdural approach 1 case, transoccipital and transtentorial approach 1 case. All patients had clinical improvement, there was no surgical mortality and morbidity. Postoperative DSA confirmed obliteration of DAVF in 3 cases, MRI demonstrated the thrombosis of venous aneurysm and the disappearance of previous brainstem edema, partial thrombosis of venous aneurysm in 1 case. Follow-up study ranging from 1 to 2 year showed no recurrence and all patients resume their full activities. CONCLUSIONS: Tentorial DAVF is an aggressive vascular lesion, causing subarachnoid hemorrhage and progressive neurological deficits. Prompt diagnosis and definite treatment for tentorial DAVF are mandatory. Obliteration of the nidus and/or leptomeningeal venous drainage should be the goal of treatment. Microsurgical procedures with/without endovascular intervention are the best choice of treatment.

Adult↗
PubMed2005

Treatment of pituitary adenomas with a transsphenoidal approach.

OBJECTIVE: To evaluate the overall therapeutic effectiveness of transsphenoidal microsurgery for pituitary adenomas and explore the surgical technique, application of new technology, and postoperative follow-up. METHODS: The clinical presentation, imaging features, endocrine examination, pathological types, conditions of operation, postoperative complications, and follow-up of 4050 patients with pituitary adenomas who had undergone transsphenoidal microsurgery from December 1981 to January 2004 were analyzed retrospectively. RESULTS: During the past 6 years, total tumor resection (under microscope) has been achieved in 97.3% of the patients with Hardy Grade I adenomas, 95.2% of Hardy Grade II, 90.4% of Hardy Grade III, and 47.4% of Hardy Grade IV. The percentages of total and subtotal resection achieved extended from 87.6% before 1987 to 96.9% in 2003. CONCLUSION: With the improvement of microsurgical technique and application of novel technology, the indications for transsphenoidal microsurgery for pituitary adenomas were increasingly extended. We believe that more than 90% of pituitary adenomas could be treated by the transsphenoidal approach and totally removed through the microscope. The transnasal perpendicular plate-sphenoid sinus approach will be the dominant mode. Routine postoperative radiotherapy is not required for patients with total resection.

Adenoma↗
PubMed2005

Upregulated gene expression of local brain-derived neurotrophic factor and nerve growth factor after intracisternal administration of marrow stromal cells in rats with traumatic brain injury.

OBJECTIVE: To examine the effects of rat marrow stromal cells (rMSCs) on gene expression of local brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) after injection of rMSCs into Cistern Magnum of adult rats subjected to traumatic brain injury (TBI). METHODS: A modified Feeney's TBI model was created in 48 adult rats. rMSCs were harvested from 3-month-old rats, and injected into Cistern Magnum in 24 rats subjected to TBI (Group cell transplantation). Saline was given through Cistern Magnum to another 24 rats subjected to TBI (Group saline control). Animals were sacrificed 1, 2 and 3 weeks after intervention, and special brain tissue blocks were dissected for total RNA extraction from each block. BDNF and NGF mRNA were reverse-transcribed into cDNA and further expanded by polymerase chain reaction (PCR). The expression of target genes was evaluated using semi-quantitative methods. RESULTS: Group cell transplantation had higher BDNF and NGF gene expressions than Group saline control during a period of less than 3 weeks (P<0.05). CONCLUSIONS: rMSCs transplantation via Cistern Magnum in rats subjected to traumatic brain injury can enhance expressions of local brain NGF and BDNF to a certain extent.

Animals↗
PubMed2005

[Cerebral revascularization in treatment of intractable aneurysms].

OBJECTIVE: To evaluate the effectiveness of cerebral revascularization in the treatment of intractable aneurysms and to discuss the indications, surgical techniques, and the outcome of the revascularization. METHODS: During the recent 4-year period, 9 radical artery grafts were performed in patients with intractable or giant internal carotid artery (ICA) aneurysms. The indications for cerebral revascularization included parent vessel occlusion during the treatment of the intractable aneurysms with poor collateral circulation or the young patients. Modified techniques were taken to use the main trunk of superficial temporal artery (STA) as donor, while M3 branches near the bifurcation of the M2 segment of the middle cerebral artery (MCA) were chosen as the recipient arteries. STA-Radial artery (RA)-MCA bypass was followed by parent vessel occlusion via chronic cervical ICA ligation or balloon occlusion. RESULTS: Postoperative angiography demonstrated the patency of the grafts in eight cases. The procedure of the parent vessels occlusion was uneventful in these patients. Follow-up showed the patients were in excellent conditions after successful treatment of aneurysms. Significantly delayed filling of the graft was revealed in one patient, who could not tolerate balloon occlusion test and occlusion of parent artery failed. CONCLUSIONS: Extracranial-to-intracranial bypass followed by parent vessel occlusion is a safe and effective method to treat intractable ICA aneurysms. Radical artery as graft can offer high-flow revascularization with less complications. Combined surgical and endovascular treatment might be the future direction for the treatment of the difficult aneurysms.

Adolescent↗
PubMed2004

[Jugular foramen schwannomas: a review of 17 cases].

OBJECTIVE: To analysis the clinical presentation, radiological findings, surgical techniques and outcomes of jugular foramen (JF) schwannomas. METHODS: We reviewed our 10-year experience in the surgical treatment of 17 patients suffered from JF schwannomas in Hua Shan Hospital, Shanghai. A total of 8 males and 9 females with a mean age of 42 years underwent surgical procedures. A relative long period of 53-month symptomatic history was shown before surgery. The main clinical presentation are vertigo and hearing difficulty in 10 cases, atrophy of unilateral muscles of tongue in 9 cases, involvement of lower cranial nerve in 8 cases. The classification of tumors was type A (at cerebellopontine angle with minimal enlargement of the JF) in five cases, type B (JF with intracranial extension) in 3 cases, type C (extracranial tumors with JF extension) in 2 cases and type D (dumbbell-shaped with both intra-and extracranial components) in 7 cases. RESULTS: Far lateral approaches were used in 10 cases, retrosigmoid suboccipital approaches were used in 5 cases. Submandibular approaches were selected in other 2 cases. Gross total removal was achieved in 12 cases, and subtotal removal in 5 cases. Follow-up revealed marked improvement from preoperative symptoms in 9 cases and no additional deficits in 3 cases. 5 cases suffered from additional neurological deficits. There were two cases of temporary hoarseness and gradually improved within follow-up. Two patients suffered from swallowing problems as a new deficit. One patient had facial palsy. CONCLUSIONS: JF schwannomas can be surgically treated with relative good outcomes. Surgical approaches should be tailored according to the tumor extension.

Accessory Nerve Diseases↗
PubMed2004

[Transplantation of gene-transfected neural stem cells for transient cerebral ischemia in rats].

OBJECTIVE: To detect the expression and the role of vascular endothelial growth factor (VEGF)-transfected neural stem cells (NSCs) in rat brain subjected to ischemia. METHODS: Fetal NSCs were cultured from E14 days SD rats and transfected with VEGF121 gene by using lipofectAMINE technique. The gene expression of transfected cells was detected by RT-PCR and immunofluorescent staining in vitro. Temporary middle cerebral artery occlusion (tMCAO) model was established in 40 SD rats and then rate were randomly divided into (1) control group (n = 10), (2) PBS transplantation group (n = 10), (3) neural stem cells transplantation group (n = 10), and (4) VEGF-secreting neural stem cells transplantation group (n = 10). BrdU-labelled NSCs and VEGF-secreting NSCs were transplanted into the penumbra zones respectively 3 days after the tMCAO model was established. Neurological Severity Score (NSS) was checked in all groups 2, 4, 6, 8, 10, 12 weeks respectively after transplantation. One and 12 weeks after the transplantation, 10 rats in the group (4) were killed and then brains taken out respectively. By using immunofluorescent staining, the VEGF expression of transplanted cells 1 week after transplantation, differentiation and migration of transplanted neural stem cells 12 week after transplantation were detected respectively. RESULTS: VEGF-transfected neural stem cells could continuously express gene products during the first 2 weeks. Both transfected NSCs and their progeny expressed VEGF gene products, which was demonstrated by fluorescence study. There were no significant differences in NSS in groups 4 when tMCAO models were just established. However, the values of NSS in (4) group were 5.8 +/- 1.5, 5.0 +/- 1.0, 4.6 +/- 1.0, 4.0 +/- 0.7, 4.0 +/- 1.0, 3.8 +/- 0.4 from 2 approximately 12 weeks after transplantation, significantly lower than those in groups (1) and (2) 8 weeks (P = 0.008) and those in groups (1), (2) and (3) 12 weeks (P = 0.000) after transplantation. NSS in group (3) was also lower than that in groups (1) and (2) 8 and 12 weeks after transplantation. One week after transplantation, immunofluorescent staining showed that VEGF-transfected NSCs migrated and expressed VEGF into hosts' brains. Twelve weeks after transplantation, transplanted NSCs survived and migrated, some of them differentiated to neurons and integrated well with hosts' cytoarchitectural components. CONCLUSION: VEGF-transfected NSCs express gene products during the early time after transplantation, which reduce brain injury through protecting the vascular system against ischemia and reperfusion injury. Transplantation of VEGF-transfected NSCs might be a novel method for treatment of cerebral ischemia.

Animals↗
PubMed2004

[Analysis of the results of gamma knife radiosurgery for hemangioblastomas of the brain and the factors related to the tumor recurrence].

OBJECTIVE: To assess the 5-year-result of leksell gamma knife (LGK) in controlling hemangioblastomas of the brain (HB) and to analyze the factors related to tumor recurrence or development of new tumors. METHODS: From November 1993 to September 2001, 35 patients, 28 males and 7 females, aged 36 (16 approximately 61), 18 with multiple tumors and 17 with solitary tumor, the number of tumors being 93 in total, were treated by LGK. Twenty-one patients with HBs were associated with von Hippel-Lindau disease (VHLD). The tumor size ranged 5 approximately 55 mm with a mean size of 13 mm. The mean maximum irradiation dose was 35.6 Gy (20.0 approximately 50.0 Gy) at tumor center and the mean minimum dose was 17.2 Gy (12.0 approximately 24.0 Gy) at tumor periphery. Fisher exact test, independent T test and Wilcoxon rank sum W test were used to analyze the results of LGK on solitary and multiple HBs, the recurrent time of the HBs, and the relation between minimum irradiation dose and tumor control. RESULTS: 35 patients had been followed for 24 - 114 months with a mean value of 66 months. 29 patients were alive and 6 died. Of the 29 patients 21 achieved satisfying tumor control, and 8 patients underwent open surgery because of tumor-associated cysts enlarging or development of new tumors after LGK. 21 patients had improvement or remained stable in neurological status. Of the 8 reopened patients, 2 had deteriorated symptoms and the other 6 remained neurologically stable. Of the 35 patients, 7 developed new tumor during the follow-up period, and 5 had second LGK. Tumor control: Of the 29 cases, solitary or multiple tumors in 23 patients decreased in volume or remained the same, although two developed new tumors. The result of LGK in controlling HBs showed no significant difference between the solitary and multiple HBs (P > 0.05), but the dose of long-term tumor control was significantly higher than that of uncontrolled tumors (W = 98, P < 0.01). The tumor control rate was 94% 1 year after; 85% 2 years after; 82% 3 years after; 79% 4 years after; and 71% 5 years after. For the patients with solitary tumor, the mean time of development of new tumor was 63 months, but for the patients with multiple HBs, the time was 25 months. There was a significant difference between the two groups (t = 3.987, P < 0.001). With margin dose of 18 Gy, histopathology showed that no tumor cell was found and there were coagulation necrosis, hyaline degeneration and fibrosis tissues in the tumor nodule 48 months after LGK. CONCLUSION: LGK is a good choice for small- or medium-sized, solid HB in long term, especially when tumor margin dose is 16 - 20 Gy. Although LGK can treat multiple tumors in one single treatment session, for HB in patients associated with VHLD, LGK faces the problem of tumor recurrence or development of new tumor.

Adolescent↗