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Biomedical subjects

S H Chen

Publications and source records attributed to S H Chen.

At least 73 records · Page 4Linked to original sources
PubMed2001

Quantitative detection of N(7)-(2-hydroxyethyl)guanine adducts in DNA using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry.

High-performance liquid chromatography (HPLC) was combined with electrospray ionization tandem mass spectrometry (ESI-MS/MS) to develop a sensitive and selective method for the quantitative measurement of N(7)-(2-hydroxyethyl)guanine (N(7)-HEG) adducts in DNA obtained from ethylene oxide-exposed biological samples. Selected reaction monitoring (SRM) was used as the detection mode while the fragmentation product ion at m/z 152 generated from the precursor protonated N(7)-HEG (m/z 196) was monitored. The detection limits for N(7)-HEG were estimated by twofold serial dilution and determined to be 4 fmol in neat standard solution and 16 fmol when a matrix effect is considered. When the mass spectrometer was operated in the selected ion monitoring mode using only the first quadrupole (without MS/MS function), the detection limits increased to 128 fmol and 1 pmol (when matrix effect is considered), respectively. A good linear correlation (R(2) = 0.999) was observed for signal intensities obtained by injecting 16 fmol--33 pmol of N(7)-HEG into the HPLC/ESI-MS/MS system. Hep G2 cells were incubated for 8 h with medium containing various concentrations of ethylene oxide (ranging from 0.05 to 5.0 mM). A dose-response relationship was established, indicating that the adduct formation increases with the exposure level. The method shows potential, although the detection limit needs to be lowered for practical applications, for use in monitoring N(7)-HEG formation in other biological systems.

Carcinoma, Hepatocellular↗
PubMed2001

Afferent synaptic contacts on glycine-immunoreactive neurons in the rat cuneate nucleus.

This study was aimed to clarify whether the primary afferent terminals (PATs), GABAergic terminals, and glutamatergic terminals made direct synaptic contacts with glycine-IR neurons in the cuneate nucleus of rats. In this connection, injection of the anterograde tracer WGA-HRP into brachial plexus, antiglycine preembedding immunoperoxidase, and anti-GABA, along with antiglutamate postembedding immunogold labeling, were used to identify the PATs, glycine-IR neurons, GABA-IR terminals, and glutamate-IR terminals, respectively. The present results showed that HRP-labeled PATs, immunoperoxidase-labeled glycine-IR terminals, immunogold-labeled GABA-IR, and glutamate-IR terminals made axodendritic synaptic contacts with immunoperoxidase-labeled glycine-IR neurons. The latter three presynaptic elements also formed axosomatic synapses with glycine-IR neurons. Statistical analysis has shown that the minimum diameter of the glycine-IR dendrites postsynaptic to the above-mentioned four presynaptic elements did not differ significantly. In addition, the synaptic ratio of the glutamate-IR terminals on the glycine-IR dendrites was higher than that of GABA-IR terminals. The synaptic ratio of the GABA-IR terminals on glycine-IR dendrite was in turn higher than that of the PATs and glycine-IR terminals. It is suggested that the PATs and glutamate-IR terminals on the glycine-IR neurons may be involved in subsequent postsynaptic inhibition for spatial precision of lateral inhibition. On the other hand, the GABA-IR and glycine-IR terminals which make synaptic contacts with the dendrites of glycine-IR neurons may provide a putative means for disinhibition or facilitation to maintain the baseline neuronal activity in the rat cuneate nucleus. The results of quantitative analysis suggest that glutamate act as the primary excitatory neurotransmitter, while GABA, when compared with glycine, may serve as a more powerful inhibitory neurotransmitter on glycine-IR neurons in the rat cuneate nucleus.

Animals↗
PubMed2001

Intratumoral adenovirus-mediated suicide gene transfer for hepatic metastases from colorectal adenocarcinoma: results of a phase I clinical trial.

Animal studies have shown that direct injection of an adenoviral vector (Adv.RSV-tk) expressing the herpes thymidine kinase gene into established tumors in the liver, followed by systemic ganciclovir administration, was effective in inducing tumor necrosis. Toxicities were minimal at therapeutically effective vector doses, although severe hepatic necroinflammation was seen at much higher supratherapeutic doses. We conducted a clinical phase I trial in patients with metastatic colorectal adenocarcinoma in the liver to assess the safety of intratumoral Adv.RSV-tk injection (escalating doses) followed by intravenous ganciclovir (fixed dose). The vector was injected into a metastatic tumor in the liver under local anesthesia by percutaneous needle placement with concurrent ultrasonographic monitoring to prevent injection or leakage into adjacent normal liver structures. We treated 16 patients in five dose level cohorts of Adv.RSV-tk, from 1.0x10(10) to 1.0x10(13) virus particles per patient. Hepatic toxicities were low, with transient grade 1 elevations in serum aminotransferase levels in 3 of 16 patients. Other toxicities were also transient: grade 2-3 fevers in 5 of 16 patients, grade 3 thrombocytopenia in 1 of 16 patients, and grade 2 leucopenia in 3 of 16 patients. These results indicate that Adv.RSV-tk can be safely administered by percutaneous intratumoral injection in patients with hepatic metastases at doses up to 1.0x10(13) virus particles per patient, and can provide the basis for future clinical trials involving intratumoral adenoviral vector injection.

Adenocarcinoma↗
PubMed2001

Immunopathogenesis of dengue virus infection.

Dengue virus infection causes dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS), whose pathogeneses are not clearly understood. Current hypotheses of antibody-dependent enhancement, virus virulence, and IFN-gamma/TNFalpha-mediated immunopathogenesis are insufficient to explain clinical manifestations of DHF/DSS such as thrombocytopenia and hemoconcentration. Dengue virus infection induces transient immune aberrant activation of CD4/CD8 ratio inversion and cytokine overproduction, and infection of endothelial cells and hepatocytes causes apoptosis and dysfunction of these cells. The coagulation and fibrinolysis systems are also activated after dengue virus infection. We propose a new hypothesis for the immunopathogenesis for dengue virus infection. The aberrant immune responses not only impair the immune response to clear the virus, but also result in overproduction of cytokines that affect monocytes, endothelial cells, and hepatocytes. Platelets are destroyed by crossreactive anti-platelet autoantibodies. Dengue-virus-induced vasculopathy and coagulopathy must be involved in the pathogenesis of hemorrhage, and the unbalance between coagulation and fibrinolysis activation increases the likelihood of severe hemorrhage in DHF/DSS. Hemostasis is maintained unless the dysregulation of coagulation and fibrinolysis persists. The overproduced IL-6 might play a crucial role in the enhanced production of anti-platelet or anti-endothelial cell autoantibodies, elevated levels of tPA, as well as a deficiency in coagulation. Capillary leakage is triggered by the dengue virus itself or by antibodies to its antigens. This immunopathogenesis of DHF/DSS can account for specific characteristics of clinical, pathologic, and epidemiological observations in dengue virus infection.

Animals↗
PubMed2001

Early colonic carcinoma with extensive lymph node metastases: case report and review of literature.

An 81-year-old woman had an early carcinoma invading focally into the upper submucosa of the middle-transverse colon, which was accompanied by extensive lymph node metastases and resulted in a poor prognosis. Although her tumor was small and flat, a rim of pale yellow-speckled mucosa adjacent to the tumor enabled its earlier detection. To further study the exceptional lymph node metastases we studied the expression of intestinal trefoil factor and sialyl Tn antigen immunohistochemically on the resected specimen. Their simultaneous expression in lymph node metastasis further supports the aggressive nature of this tumor.

Adenocarcinoma↗
PubMed2001

A novel genetic island of meningitic Escherichia coli K1 containing the ibeA invasion gene (GimA): functional annotation and carbon-source-regulated invasion of human brain microvascular endothelial cells.

The IbeA (ibe10) gene is an invasion determinant contributing to E. coli K1 invasion of the blood-brain barrier. This gene has been cloned and characterized from the chromosome of an invasive cerebrospinal fluid isolate of E. coli K1, strain RS218 (018:K1: H7). In the present study, a genetic island of meningitic E. coli containing ibeA (GimA) has been identified. A 20.3-kb genomic DNA island unique to E. coli K1 strains has been cloned and sequenced from an RS218 E. coli K1 genomic DNA library. Fourteen new genes have been identified in addition to the ibeA. The DNA sequence analysis indicated that the ibeA gene cluster was localized to the 98 min region and consisted of four operons, ptnIPKC, cglDTEC, gcxKRCI and ibeRAT. The G+C content (46.2%) of unique regions of the island is substantially different from that (50.8%) of the rest of the E. coli chromosome. By computer-assisted analysis of the sequences with DNA and protein databases (GenBank and PROSITE databases), the functions of the gene products could be anticipated, and were assigned to the functional categories of proteins relating to carbon source metabolism and substrate transportation. Glucose was shown to enhance E. coli penetration of human brain microvascular endothelial cells and exogenous cAMP was able to block the stimulating effect of glucose, suggesting that catabolic regulation may play a role in control of E. coli K1 invasion gene expression. Our data suggest that this genetic island may contribute to E. coli invasion of the blood-brain barrier through a carbon-source-regulated process.

Amino Acid Sequence↗
PubMed2001

Correlation analyses on binding behavior of heavy metals with sediment matrices.

This article presents the amounts of heavy metals bound to the sediment matrices (carbonates, Fe-oxides, Mn-oxides, and organic matter), the correlations between any two heavy-metal binding fractions, and the correlations between sediment matrices and their heavy-metal binding fractions. Data consisted of 313 sets obtained from five main rivers (located in southern Taiwan) were analyzed by statistical methods. Among six heavy metals analyzed (Zn, Cu. Pb, Ni, Cr, and Co), the statistical results show that Zn is primarily bound to organic matter, and Cr is primarily bound to Fe-oxides. Principal component analysis (PCA) and correlation analysis (CA) result in significant correlations between carbonates bound Ni and carbonates bound Cr, Fe-oxides bound Ni and Fe-oxides bound Cr, and Mn-oxides bound Cu and Mn-oxides bound Cr. From linear regression results, the levels of the six heavy metals bound to either organic matter or Fe-oxides is moderately dependent on the contents of organic matter or Fe-oxides, especially true for Cr and Pb. According to slope values of linear regression, Cu and Cr have the highest specific binding amounts (SBA) to organic matter and Fe-oxides, respectively. A significant correlation between organic matter and organically bound heavy metals implied that organic matter contained in the sediments of the Potzu river and the Yenshui river can be adequately used as a normalizing agent. However, the six heavy metals bound to either carbonates or Mn-oxides do not correlate with carbonates or Mn-oxides. The obtained results also imply that competitions of various sediment phases in association with heavy metals occur, and organic matter and Fe-oxides are more accessible to heavy metals than other sediment phases.

Binding Sites↗
PubMed2001

Chemical binding of heavy metals in anoxic river sediments.

Acid volatile sulfides (AVS) in sediments are available for binding with divalent cationic metals through the formation of insoluble metal-sulfide complexes, thereby controlling the metal bioavailability and subsequent toxicity to benthic biocommunities. However, when the molar concentrations of simultaneously extracted metals (SEM) were greater than AVS, the unexpectedly low or nondetectable levels of metal in pore water could also be found. Thus, except AVS, additional binding phases in sediments were supposed to provide the binding sites for SEM. The aims of this study are to realize the spatial distribution of AVS, SEM, and other binding phases of heavy metals in anoxic sediments of the Ell-Ren river and to elucidate what may be the main additional binding phases except AVS in the anoxic river sediments. By comparing the spatial distributions of SEM/ AVS ratio with various binding phases in extremely anoxic sediments (redox potential was between -115 and -208 mV), both organic matter and carbonates could be considered to be the main additional binding phases of SEM other than AVS. In addition, AVS appeared to have the priority to bind with SEM. By comparing the binding phases of heavy metals before and after AVS extraction, it could be found that Fe-oxides could also be considered to be the main additional binding phase associated with Zn in slightly anoxic sediments (redox potential was between -50 and -130mV), while organic matter with Cu being the next.

Geologic Sediments↗
PubMed2001

Response of amoeboid and differentiating ramified microglia to glucocorticoids in postnatal rats: a lectin histochemical and ultrastructural study.

After glucocorticoid injection(s), the number of amoeboid microglial cells (AMC) in the corpus callosum labelled by lectin was markedly reduced when compared with the corresponding control rats. In rats killed at the age of 7 days, all the labeled cells differentiated to become ramified microglia. Ultrastructurally, the AMC in glucocorticoid-injected rats were extremely vacuolated and showed increased lipid droplets. Furthermore, the cells displayed varied lectin labelling patterns especially at both the trans saccules of the Golgi apparatus and lysosomes. In differentiating ramified microglia, massive cellular debris and lectin-stained vesicles or vacuoles were observed; some of the latter appeared to fuse with the plasma membrane. The most striking feature after glucocorticoid (GCC) treatment was the complete diminution of lectin labelling at the Golgi saccules in some differentiating ramified microglia. The present results have demonstrated different effects of glucocorticoids on AMC and differentiating ramified microglia. The differential response of AMC and differentiating ramified microglia to the immunosuppressive drugs may be attributed to the fact that these cells in the postnatal brains subserve different functions or that they are at different differentiation stages. In other words, the sensitivity of microglial cells to the immunosuppressive drugs is dependent upon the stage of cell maturation/differentiation.

Animals↗
PubMed2001

Protective effect of excitatory amino acids on cold-restraint stress-induced gastric ulcers in mice: role of cyclic nucleotides.

Previous studies have shown that excitatory amino acids (EAAs) and their receptors may play important roles in the mammalian enteric system. In this study, we investigated whether EEAs, including L-glutamate (L-Glu) and subtypes N-methyl-D-aspartate (NMDA), kainic acid (KA), and quisqualic acid (QA), reduce cyclic AMP (cAMP) levels and play a role in protecting gastric lesions in cold-restraint stress (CRS) mice. First, we found that dose-dependent administration of four selected EAAs significantly attenuated the increase of cAMP content and exhibited a protective effect on the development of gastric lesions induced by CRS. Second, CRS treatment exhibited a decrease of cGMP content and an increase of cAMP content with marked time-dependent changes, and a high cAMP/cGMP ratio in mice gastric mucosa. Third, pretreatment with 0.25 microg/kg or 0.5 microg/kg dibutyryl cGMP (db-cGMP) exhibited protective effects on CRS-induced gastric lesions, with preventive ratios of 24.61% and 35.32%, respectively. Moreover, db-cGMP at 0.5 microgg/kg significantly attenuated the increase in both cAMP content and the cAMP/cGMP ratio in CRS-treated gastric mucosa. In contrast, db-cAMP exhibited no protective effect, and significantly decreased cGMP content and increased the cAMP/cGMP ratio. These results suggest that EAAs significantly reduce CRS-induced gastric ulcers in mice. The possible mechanism of the antiulcer activity of EAAs may be related to a decrease in the cAMP content in the gastric mucosa of mice. In addition, an increase of the cAMP/cGMP ratio significantly involved in CRS-induced gastric ulcer formation in mice.

Animals↗
PubMed2001

Olfactory-evoked regional cerebral blood flow in Alzheimer's disease.

Olfaction is impaired in Alzheimer's disease (AD). It was hypothesized that AD would reduce olfactory-evoked perfusion in mesial temporal olfactory (piriform) cortex, where neuropathology begins. Seven AD patients and 8 elderly controls (ECs) underwent olfactory threshold and identification tests and olfactory stimulation during positron emission tomography. Odor identification was impaired in AD, but threshold was not. Olfactory stimulation in ECs activated right and left piriform areas and right anterior ventral temporal cortex. AD patients had less activation in right piriform and anterior ventral temporal cortex but not in the left piriform area. Although orbital cortex did not activate in ECs, there was a significant between-groups difference in this area. Right piriform activation correlated with odor identification. Impaired odor identification likely reflects sensory cortex dysfunction rather than cognitive impairment. Given olfactory bulb projections to the mesial temporal lobe, olfactory stimulation during functional imaging might detect early dysfunction in this region.

Aged↗
PubMed2001

Investigation of the extent of gastric metaplasia in the duodenal bulb by using methylene blue staining.

BACKGROUND AND AIMS: The existence of gastric metaplasia (GM) of the duodenal mucosa has been considered to be highly related to the recurrence of duodenal ulcers (DU). The aims of this study are to evaluate the usefulness of methylene blue staining in the detection of GM, and to clarify the relationship between GM and the deformity of the duodenal bulb. METHODS: Fifteen patients with healed DU and four patients with symptoms of dyspepsia without evidence of ulcers were enrolled into this endoscopic study. During each endoscopy, methylene blue was sprayed evenly on the duodenal bulb, and biopsies were taken from blue-stained and unstained areas. The existence and extent of GM were assessed histologically and grossly. The correlation between duodenal bulb deformity and the extent of GM was also studied. RESULTS: The mean score of methylene blue non-staining (MBNS) was 0, 1.30 +/- 0.15, and 3.00 +/- 0.00 in group A (non-ulcer patients), group B (patients with healed DU and with normal-shaped bulb) and C (patients with healed DU and with deformed duodenal bulb), respectively; showing significant differences among the groups (P < 0.05 in each). Both the existence and the grading of GM were higher in unstained specimens than in blue-stained specimens (100 vs 16.6%, P < 0.0001 and 3.62 +/- 0.09 vs 0.19 +/- 0.06, P < 0.001, respectively). CONCLUSIONS: Methylene blue non-staining can be applied to investigate the existence and extent of GM in the duodenal bulb accurately. The incidence of GM in the duodenal bulb was higher in patients with healed ulcers than in non-ulcer patients. Patients with deformed duodenal bulbs have a higher extent of GM than those without deformed duodenal bulbs.

Adult↗
PubMed2001

Adjuvant sclerotherapy after ligation for the treatment of esophageal varices: a prospective, randomized long-term study.

BACKGROUND: To assess the efficacy of adjuvant sclerotherapy after banding for the treatment of esophageal varices, a randomized trial was carried out of endoscopic variceal ligation (EVL) alone with sequential sclerotherapy versus sequential ligation-sclerotherapy (SLS) after banding with respect to variceal eradication, associated complications, and recurrence of varices. METHODS: One hundred patients qualified for this study. Fourteen patients were not included for the following reasons: 6 chose not to participate, 4 had fundal varices, and 4 had some form of cancer. Of the remaining 86 patients in the study, 42 underwent EVL alone and the other 44 SLS. Variceal ligation was begun in the region of the gastroesophageal junction, with subsequent ligatures applied cephalad 3 to 5 cm; ligation was repeated every 2 weeks until variceal obliteration. For SLS, ligation was also begun in the region of the gastroesophageal junction and repeated until varices were reduced to F1 size. Subsequently, these patients underwent sclerotherapy with between 6 and 8 mL of sodium tetradecyl sulfate (free hand technique). RESULTS: No significant differences were found between EVL alone and SLS with regard to variceal eradication, development of associated complications, and recurrent bleeding during a follow-up of 2 years. The probability of variceal recurrence requiring further treatment after 1 year was 14% for the SLS group and 26% for EVL group patients. Another year later, the probability of variceal recurrence was 24% and 45%, respectively, for the SLS and EVL groups. CONCLUSIONS: Because a significantly lower rate of variceal recurrence was found for SLS patients, sequential sclerotherapy followed by ligation to eradicate those varices too small to easily band may be a better procedure.

Combined Modality Therapy↗
PubMed2001

The synergistic effect of thrombopoietin in erythropoiesis with erythropoietin and/or IL-3 and myelopoiesis with G-CSF or IL-3 from umbilical cord blood cells of full-term neonates.

The authors sought to determine whether recombinant human thrombopoietin (TPO) acts synergistically with other cytokines on burst-forming unit-erythroid (BFU-E)-derived and colony-forming unit-granulocyte/macrophage (CFU-GM)-derived colony formations from cord blood. Cord blood nonadherent mononuclear cells (MNC) from normal full-term neonates were cultured in a methylcellulose system. When cultured with 5 x 10(4) MNC/mL, erythropoietin (EPO) 2 U/mL, interleukin-3 (IL-3) 50 ng/mL, and/or TPO 400 ng/mL (experiment 1), the addition of TPO to EPO gave rise to more BFU-E-derived colonies (p = .002). The addition of TPO to EPO + IL-3 gave rise to more BFU-E-derived colonies (p = .006) also. TPO synergizes erythropoiesis from cord blood. When cultured with IL-3 50 ng/mL, granulocyte colony-stimulating factor (G-CSF) 25 ng/mL, and/or TPO 400 ng/mL, the addition of TPO to IL-3 gave rise to more CFU-GM-derived colonies (p = .002). The addition of TPO to G-CSF gave rise to more CFU-GM-derived colonies (p = .002) also. TPO synergizes myelopoiesis from cord blood. Thus, TPO has synergistic effects on both erythropoiesis and myelopoiesis from cord blood. In the identical conditions of culture, cord blood had significantly greater BFU-E-derived or CFU-GM-derived colony formation than bone marrow (in a previous report by the authors) did. When cultured under conditions similar to those of experiment 1, but with 1 x 10(4) cord blood MNC/mL and TPO 100 ng/mL (experiment 2), results similar to those in the experiment 1 also revealed that TPO has synergistic effects on erythropoiesis and myelopoiesis from cord blood. In every individual assay, the numbers of BFU-E-derived or CFU-GM-derived colonies in experiment 1 were significantly higher than those in experiment 2.

Cell Count↗
PubMed2001

Multivariate correlations of geochemical binding phases of heavy metals in contaminated river sediment.

Distributions of geochemical binding phases of seven heavy metals (Cr, Cu, Co, Zn, Ni, Pb, and Cd) in sediment cores taken from six heavily polluted sites of the Ell-Ren River in Southern Taiwan were studied. Sequential extraction procedures (SEP) were used to determine the variations of heavy metal binding phases (exchangeable, bound to carbonates, bound to manganese-oxides, bound to iron-oxides, and bound to organic matter) in different sediment depths. Multivariate analyses were used to explore the correlations among these geochemical binding phases of heavy metals. Results showed that the total amounts of various binding phases of heavy metals significantly varied with sediment depth, but their binding behaviors in various phases did not significantly change with depth. The organic matter content in the sediments increased with increasing Fe-oxide content. In addition, the binding affinities of carbonates with Zn, Pb, and Ni were higher than the affinities of carbonates with the other heavy metals. The binding affinity of Fe-oxides with Cr was higher than the affinities of Fe-oxides with the other heavy metals. Both correlation matrixes and principal component analyses demonstrated that distributions of Cu, Zn, Ni, and Cd had significant correlations with each other in both different depth horizons and various geochemical binding phases. The results indicate that these heavy metals might be discharged from the same pollution sources in the past, and also showed stable geochemical binding behaviors with the high silt sediment. However, Co had a poor correlation with the other six heavy metals in various binding phases, except with organic matter. Binding behaviors of Pb in the phases of bound to carbonates and exchangeable were different from the other six heavy metals. Cu was inversly correlated with the other six heavy metals in its binding behavior with reducible phases (Fe-/Mn-oxides).

Carbonates↗
PubMed2001

Concomitant ipsilateral pedicled fibular transfer and free muscle flap for compound tibial defect reconstruction.

Three patients with compound injuries of the lower extremities were treated with pedicle fibular grafts and a free muscle flap concomitantly. There were 1 female and 2 male patients, all of whom sustained high-energy trauma in a motor vehicle accident. The bone defect of the tibia ranged from 8 to 12 cm. The size of the soft-tissue defect ranged from 24 x 15 cm to 28 x 15 cm. All patients underwent preoperative angiography to ensure the patency of the peroneal artery and to avoid its use by risking viability of the leg. All patients were treated with an antegrade-flow pedicle fibular graft. The fibular graft was inserted as a single strut in 2 patients and as a double-barrel strut in 1 patient. The pedicle of the free muscle flap was anastomosed to the distal runoff of the fibular bone flap. All free muscle flap transfers succeeded without complication. Bone scans performed on postoperative day 7 showed viability of transferred bone. The average time to radiological union was 9 months, and the average time to full weight bearing was 12 months. Screw loosening occurred in 2 patients and osteomyelitis was noted in another patient who was treated successfully with sequestrectomy and antibiotics. Indications for this technique are a large segmental bone defect with a huge soft-tissue defect, and patency of the peroneal artery and at least one other major artery. This method provides the advantages of one-stage reconstruction, avoidance of contralateral donor site morbidity, easy control of infection, and chance for early weight bearing. When selected carefully, this technique can be considered when one wants to avoid a two-stage, two free flap transfer.

Accidents, Traffic↗
PubMed2001

Minimal access surgery in managing anterior lumbar disorders.

Traditional anterior lumbar surgery usually requires a long and sometimes painful skin incision. The current study evaluated the feasibility and safety of minimal access surgery for anterior lumbar disorders, emphasizing indications, operative technique, and the minimum 2-year followup results. From May 1996 to December 1997, the authors used this technique on 25 patients whose indications for surgery included syndromes of failed back surgery, selected cases of lumbar disc herniations, tuberculous or pyogenic spondylitis, selected spondylolisthesis, and vertebral tumors. In 23 of 25 patients, the site of interest was approached through a left flank incision, regardless of the laterality of the lesion. The mean length of the main incision was 5 cm. There were no injuries to great vessels or any neurologic deterioration after the procedures. Solid interbody fusion could be identified radiographically between 3 and 6 months after surgery. At a mean followup of 39.6 months, nine patients had excellent clinical outcomes, 11 patients had good outcomes, two patients had fair outcomes, and one patient had a poor outcome. The authors think such minimal access surgery is simple, effective, and safe for anterior lumbar disorders. The merits of the current technique include no need for endoscopic, microscopic, or complex surgical instruments, a lower amount of radiation exposure during surgery, and a shortened learning curve because the approach is similar to the anterior open lumbar technique, although the skin incision is only 5 cm in length.

Adult↗