Three-dimensional linear and volumetric computed tomography analysis of the frontal sinus / 대한해부학회지

The frontal sinus is one of the four paranasal sinuses in humans, and knowledge of its anatomy is important when performing surgery involving the frontal bone or sinus. Although many studies have measured the frontal sinus using radiography and computed tomography (CT), few studies have evaluated by using three-dimensional (3D) analysis. The purpose of this study was to analyze the frontal sinus using 3D reconstruction analysis and determine the differences in linear and volumetric measurements between sexes, sides, and ages. The sample comprised 281 facial CT scans: 173 and 108 from males and females, respectively. The width, height, and length of each frontal sinus and total volume were all larger in males than in females. Almost all linear and volumetric measurements were larger in young adults than in older for both sexes, but not all of the differences were statistically significant. Linear and volumetric measurements were larger for males than females regardless of age group. There were no statistically significant differences between the right and left sides except the width in males. The size of the frontal sinus was strongly influenced by sex and age. The measurements reported here might be useful for improving surgical procedures involving the frontal sinus.

Two cases of 17α-hydroxylase/17,20-lyase deficiency caused by the CYP17A1 mutation

17α-hydroxylase/17,20-lyase deficiency, caused by mutations in the cytochrome P450 family 17 subfamily A member 1 gene (CYP17A1), is an extremely rare form of congenital adrenal hyperplasia that is characterized by diverse phenotypes resulting from specific mutations. Here, we report 2 phenotypic females with 17α-hydroxylase/17,20-lyase deficiency: one with the 46,XX karyotype presenting primary amenorrhea and sexual infantilism, and the other with the 46,XY karyotype presenting a disorder of sexual development. In both cases, the serum levels of adrenocorticotropic hormone, 11-deoxycorticosterone, and gonadotropin were elevated, whereas the levels of testosterone and dehydroepiandrosterone were reduced. Next-generation sequencing revealed one patient with compound heterozygosity for p.Trp17Ter (c.51G>A) and p.His373Leu (c.1118A>T), and the other with homozygosity for p.His373Leu (c.1118A>T). This report further describes 2 cases of 17α-hydroxylase/17,20-lyase deficiency in patients who harbored a p.His373Leu substitution, commonly found in Korean individuals, and presented diverse phenotypes.

Identification of a novel point mutation in DAX-1 gene in a patient with adrenal hypoplasia congenita

X-linked adrenal hypoplasia congenita caused by a mutation in NR0B1/DAX-1 is a rare inherited disorder. Patients with adrenal hypoplasia congenita are usually diagnosed with primary adrenal insufficiency in infancy or early childhood and present hypogonadotropic hypogonadism during adolescence. Our patient first presented with adrenal crisis at the age of 2 months, which was managed with glucocorticoids and mineralocorticoids. At the age of 17 years, testicular volumes of 5 mL each and a stretched penile length of 4 cm were noted. A combined pituitary function test showed a peak luteinizing hormone level of 2.68 mIU/mL, testosterone 13.5 ng/dL, confirming hypogonadotropic hypogonadism. After whole-exome sequencing, a new variant of DAX-1, c.881T>C (p.Leu294Pro), was found. He was diagnosed with X-linked adrenal hypoplasia congenita and then treated with human choriogonadotropin for the induction of spermatogenesis as well as with steroid replacement therapy.

Two cases of 17α-hydroxylase/17,20-lyase deficiency caused by the CYP17A1 mutation

17α-hydroxylase/17,20-lyase deficiency, caused by mutations in the cytochrome P450 family 17 subfamily A member 1 gene (CYP17A1), is an extremely rare form of congenital adrenal hyperplasia that is characterized by diverse phenotypes resulting from specific mutations. Here, we report 2 phenotypic females with 17α-hydroxylase/17,20-lyase deficiency: one with the 46,XX karyotype presenting primary amenorrhea and sexual infantilism, and the other with the 46,XY karyotype presenting a disorder of sexual development. In both cases, the serum levels of adrenocorticotropic hormone, 11-deoxycorticosterone, and gonadotropin were elevated, whereas the levels of testosterone and dehydroepiandrosterone were reduced. Next-generation sequencing revealed one patient with compound heterozygosity for p.Trp17Ter (c.51G>A) and p.His373Leu (c.1118A>T), and the other with homozygosity for p.His373Leu (c.1118A>T). This report further describes 2 cases of 17α-hydroxylase/17,20-lyase deficiency in patients who harbored a p.His373Leu substitution, commonly found in Korean individuals, and presented diverse phenotypes.

Identification of a novel point mutation in DAX-1 gene in a patient with adrenal hypoplasia congenita

X-linked adrenal hypoplasia congenita caused by a mutation in NR0B1/DAX-1 is a rare inherited disorder. Patients with adrenal hypoplasia congenita are usually diagnosed with primary adrenal insufficiency in infancy or early childhood and present hypogonadotropic hypogonadism during adolescence. Our patient first presented with adrenal crisis at the age of 2 months, which was managed with glucocorticoids and mineralocorticoids. At the age of 17 years, testicular volumes of 5 mL each and a stretched penile length of 4 cm were noted. A combined pituitary function test showed a peak luteinizing hormone level of 2.68 mIU/mL, testosterone 13.5 ng/dL, confirming hypogonadotropic hypogonadism. After whole-exome sequencing, a new variant of DAX-1, c.881T>C (p.Leu294Pro), was found. He was diagnosed with X-linked adrenal hypoplasia congenita and then treated with human choriogonadotropin for the induction of spermatogenesis as well as with steroid replacement therapy.

Three-dimensional microstructures of the intracortical canals in the animal model of osteoporosis / 대한해부학회지

Osteoporosis is a major disease in aged women, increasing the risk for fractures accompanied by changes in the microarchitecture. The aim of this study was to investigate the three-dimensional (3D) histomorphology of femur diaphysis in the animal model for postmenopausal osteoporosis. The cortical bone of femur diaphysis of the rat was serially sectioned at a thickness of 5 μm and evaluated age-associated changes of the intracortical (osteonal) canal networks three-dimensionally. Cortical microstructures of 10-month old rats were not affected by ovariectomy. Intracortical canal networks were radial toward endosteal aspect and frequently interconnected across the neighboring canals with short arciform and irregular canals reminiscent for resorption spaces in ovarectomized 16-month old rats, contrary to intact canals in 16-month old control rat. Increased proportion of the periosteal circumference lamella and deformed endosteal regions with rare cortical canals hampered reconstructive histomorphology in ovarectomized rats of 26 month age. We have shown that 3D reconstruction of rat femur of the aged model over 16-month old is suitable methods that evaluate and microstructural change of the intracortical canals and cortical bone porosity by estrogen depletion.

Three-dimensional microstructures of the intracortical canals in the animal model of osteoporosis / 대한해부학회지

Osteoporosis is a major disease in aged women, increasing the risk for fractures accompanied by changes in the microarchitecture. The aim of this study was to investigate the three-dimensional (3D) histomorphology of femur diaphysis in the animal model for postmenopausal osteoporosis. The cortical bone of femur diaphysis of the rat was serially sectioned at a thickness of 5 μm and evaluated age-associated changes of the intracortical (osteonal) canal networks three-dimensionally. Cortical microstructures of 10-month old rats were not affected by ovariectomy. Intracortical canal networks were radial toward endosteal aspect and frequently interconnected across the neighboring canals with short arciform and irregular canals reminiscent for resorption spaces in ovarectomized 16-month old rats, contrary to intact canals in 16-month old control rat. Increased proportion of the periosteal circumference lamella and deformed endosteal regions with rare cortical canals hampered reconstructive histomorphology in ovarectomized rats of 26 month age. We have shown that 3D reconstruction of rat femur of the aged model over 16-month old is suitable methods that evaluate and microstructural change of the intracortical canals and cortical bone porosity by estrogen depletion.

Use of the orbito-occipital line as an alternative to the Frankfort line / 대한해부학회지

Frankfort horizontal line, the line passing through the orbitale and porion, is one of the most widely used intracranial landmarks in cephalometric analysis. This study investigated the use of the orbito-occipital line extending from the orbitale to the external occipital protuberance as a novel horizontal line of the skull for substituting the Frankfort horizontal line. We evaluated the reproducibility of the new landmark and measured the angle between the orbito-occipital line and the Frankfort line. This study was conducted on 170 facial computed tomography (CT) scans of living adults from the Department of Plastic Surgery. After three-dimensionally reconstructed images were obtained from facial CT, the porion, orbitale, and external occipital protuberance were indicated by two observers twice. The angles between the orbito-meatal line (inferior orbital rim to porion; the Frankfort line) and the orbito-occipital line (inferior orbital rim to external occipital protuberance) were measured. There was no significant intraobserver or interobserver bias. The overall angle between the Frankfort line and orbito-occipital line was –0.5°±2.2° (mean±standard deviation). There was no statistically significant difference among side and sex. This study demonstrated good reproducibility of a new landmark—the external occipital protuberance—tested to replace the porion. The orbito-occipital line is a reliable, reproducible, and easily identifiable line, and has potential as a novel standard horizontal line to replace or at least supplement the Frankfort line in anthropological studies and certain clinical applications.

Use of the orbito-occipital line as an alternative to the Frankfort line / 대한해부학회지

Frankfort horizontal line, the line passing through the orbitale and porion, is one of the most widely used intracranial landmarks in cephalometric analysis. This study investigated the use of the orbito-occipital line extending from the orbitale to the external occipital protuberance as a novel horizontal line of the skull for substituting the Frankfort horizontal line. We evaluated the reproducibility of the new landmark and measured the angle between the orbito-occipital line and the Frankfort line. This study was conducted on 170 facial computed tomography (CT) scans of living adults from the Department of Plastic Surgery. After three-dimensionally reconstructed images were obtained from facial CT, the porion, orbitale, and external occipital protuberance were indicated by two observers twice. The angles between the orbito-meatal line (inferior orbital rim to porion; the Frankfort line) and the orbito-occipital line (inferior orbital rim to external occipital protuberance) were measured. There was no significant intraobserver or interobserver bias. The overall angle between the Frankfort line and orbito-occipital line was –0.5°±2.2° (mean±standard deviation). There was no statistically significant difference among side and sex. This study demonstrated good reproducibility of a new landmark—the external occipital protuberance—tested to replace the porion. The orbito-occipital line is a reliable, reproducible, and easily identifiable line, and has potential as a novel standard horizontal line to replace or at least supplement the Frankfort line in anthropological studies and certain clinical applications.

Effect of polishing methods on color change by water absorption in several composite resins

PURPOSE: The aim of this study was to evaluate the influence of polishing methods on the color stability of composite resins. MATERIALS AND METHODS: Two bulk-fill and four conventional resin composites were filled in cylindrical molds (6 mm diameter, 4 mm height) and light-cured. The specimens were stored in 34℃ distilled water for 24 h. Spectrophotometer was used to determine the color value according to the CIE L(*)a(*)b(*) color space. Each group was divided into three groups according to polishing methods (n = 5). Group 1 was control group (Mylar strip group), group 2 was polished with PoGo, and group 3 was polished with Sof-Lex Spiral wheels. Color evaluation was performed weekly for 4 weeks after immersion in 34℃ distilled water. The results were analyzed by generalized least squares method (P < 0.05). RESULTS: Generalized least squares analysis revealed that Sof-Lex Spiral wheels group showed the significantly lower ΔE values compared to PoGo and control group (P < 0.05). The ΔE values of polished group showed the significantly lower than the ΔE values of unpolished group (P < 0.05). Regarding color changes of composite resins, there was no significant difference between the ΔE values of Filtek Z250 and Filtek Z350 XT Universal restorative in all time intervals (P < 0.05). Tetric N-Ceram Bulk Fill showed the significantly lower ΔE values compared to other composite resins in 1, 2, 3 weeks (P < 0.05). CONCLUSION: Within the limitations of this study, polishing methods influence the color stabilities of composite resins. The group polished with Sof-Lex Spiral Wheels showed more resistance to discoloration than group polished with PoGo.

Posttraumatic Embitterment Disorder in Patients with Chronic Kidney Disease

OBJECTIVE: Posttraumatic embitterment disorder (PTED), a subgroup of an adjustment disorder, is a feeling with anger and helplessness. Hemodialysis may be a trigger event leading to PTED. We investigated the prevalence of PTED in patients with each categorized stages of chronic kidney disease (CKD) and the association between PTED and depression and functional impairment. METHODS: Patients were categorized into three groups according to the stages of CKD (stage I–II, III–IV, and V). CKD (I–II) group was defined as estimated glomerular filtration rate (eGFR) >60 ml/min/1.73 m², CKD (III–IV) group as eGFR <60 ml/min/1.73 m², and CKD (V) group as CKD stage V including patients ongoing hemodialysis. Patients were assessed for the prevalence of PTED, depression, and decreased quality of life by using the scale of PTED, Patient Health Questionnaire-9 (PHQ-9), and EuroQol Five Dimensional Questionnaires, Visual Analogue Scale (EQ-5D-VAS), respectively. RESULTS: A total of 445 patients were analyzed. The number of patients in CKD (I–II) was 166, CKD (III–IV) was 172, and CKD (V) was 107. Multivariate analysis by binomial logistic regression demonstrated that CKD (V) was significantly associated with the prevalence of PTED (odds ratio, 4.13; 95% confidence interval, 1.56–15.6; p=0.006) after adjustment for age, gender, and diabetes mellitus. Also, a significant correlation existed between PTED and EQ-5D-VAS in all stages, but the correlation was nonsignificant between PTED and PHQ-9 score in group CKD (V). CONCLUSION: The findings suggest that PTED is underdiagnosed in CKD patients. Acknowledgment and diagnosis of PTED in CKD patients may lead to a better quality of life.

Position and size of the sphenoid door jamb in the lateral orbital wall for the orbital decompression / 대한해부학회지

The aim of this study was to identify the three-dimensional topography of the sphenoid door jamb (SDJ) in the lateral orbital wall and to propose navigational guidelines for safe deep lateral decompression using surgical landmarks. The 120 orbits and SDJs of 60 subjects were three-dimensionally reconstructed using Mimics software. The mean volumes of the orbit and SDJ were 24.3 mm³ and 2.0 mm³, respectively. The mean distances from the lateral orbital margin (LOM) to the anterior and posterior margins of the SDJ were 13.2 and 36.3 mm, respectively. The mean distances from the superior orbital fissure to the LOM and to the posterior margin of the SDJ were 40.2 mm and 4.6 mm, respectively. The mean distances from the inferior orbital fissure (IOF) to the anterior and posterior margins of the SDJ were 3.8 mm and 20.5 mm, respectively. In the superior approach of the orbit, it can be predicted that the area up to 3 cm posterior from the LOM is safe, while 1 cm posterior from the safe zone could be a dangerous zone. In the inferior approach of the orbit, the safe area will be about 1 cm posterior from the anterior tip of the IOF, and the area up to 1 cm posterior from the safe zone should be approached with extreme care.

Three-dimensional and topographic relationships between the orbital margins with reference to assessment of eyeball protrusion / 대한해부학회지

This study investigated the topographic relationships among the eyeball and four orbital margins with the aim of identifying the correlation between orbital geometry and eyeball protrusion in Koreans. Three-dimensional (3D) volume rendering of the face was performed using serial computed-tomography images of 141 Koreans, and several landmarks on the bony orbit and the cornea were directly marked on the 3D volumes. The anterior-posterior distances from the apex of the cornea to each orbital margin and between the orbital margins were measured in both eyes. The distances from the apex of the cornea to the superior, medial, inferior, and lateral orbital margins were 5.8, 5.8, 12.0, and 17.9 mm, respectively. Differences between sides were observed in all of the orbital margins, and the distances from the apex of the cornea to the superior and inferior orbital margins were significantly greater in females than in males. The anterior-posterior distance between the superior and inferior orbital margins did not differ significantly between males (6.3 mm) and females (6.2 mm). The data obtained in this study will be useful when developing practical guidelines applicable to forensic facial reconstruction and orbitofacial surgeries.

High-Set or Low-Set of Korean Face / 체질인류학회지

The face is the most important for individual identification, which showed racial and regional differences. The aim of the present study was to investigate that how much highly locate the facial structures in the face. In total, 551 Korean young adult volunteers with no deformity or surgical history of the face (218 males and 333 females) were selected. Subjects were photographed while sitting and assuming a standard head position, such that the porion and inferior orbital margin were in the same horizontal plane (Frankfurt plane), and they were gazing forward. The total face height was measured vertically from trichion to gnathion. And total face height was divided three heights such as upper, mid, and lower face height. Total face height of male was larger about 6% than female. The ratio of lower face height about upper face height was calculated, it showed 55.7% in male and 50.3 in female. The face was classified into three sets including high-set, mid-set, and low-set according the ratio. The male face showed relatively high-set face, while female face showed relatively low-set face. The present study is the first study to investigate about high- or low-set face, and the result is useful data to identify characteristics of the east Asian population including Korean.

Interaction of Hydroxyethylidene bisphosphonate (HEBP) with other endodontic irrigants on tissue dissolving capacity and antimicrobial effect

PURPOSE: The purpose of this study was to evaluate tissue dissolving capacity, antimicrobial effect of Hydroxyethylidene bisphosphonate (HEBP) interacting with sodium hypochlorite (NaOCl), Ethylenediaminetetraacetic acid (EDTA) as conventional endodontic irrigants and to determine tissue dissolving efficacy depended on temperature. MATERIALS AND METHODS: A total of 80 bovine muscles were randomly distributed into 8 groups (n = 10). After their initial weights determined on a precision scale, the specimens in each group were immersed in the solutions for 5, 10 and 15 min and reweighted at each time period. Agar diffusion test inoculated with Enterococcus faecalis was performed for antimicrobial effect of each endodontic irrigants. RESULTS: The ability to dissolve organic matter was greater in NaOCl group following NaOCl and HEBP mixture. Heated NaOCl (40℃) and NaOCl/HEBP mixture was greater tissue dissolving efficacy than room temperature (25℃). Antimicrobial effect was greater and significant in the following order EDTA > EDTA + 1% NaOCl > 1% NaOCl ≥ 1% NaOCl + HEBP. CONCLUSION: HEBP as soft chelating agent does not disturb antimicrobial effect and less affected tissue dissolving efficacy as inherent properties of NaOCl. In the heated NaOCl/HEBP mixture analyzed, it dissolved more the organic matter than room temperature.

Development of atrial flutter after induction of general anesthesia and conversion to atrial fibrillation: A case report

The most frequent perioperative cardiovascular event is cardiac dysrhythmia, defined as an abnormality of cardiac rate, rhythm or conduction. Although the occurrence of arrhythmia during the perioperative period is not uncommon, a case of newly developed perioperative atrial flutter which spontaneously converts to atrial fibrillation is rare. We report a case of atrial flutter that developed immediately after induction of general anesthesia, in a 70-year-old male patient who previously had a normal sinus rhythm. Atrial flutter changed spontaneously to atrial fibrillation after discharge to the recovery room. Dysrhythmia was unresponsive to drug therapy, and the atrial fibrillation disappeared after electric cardioversion.

The impact of high serum bicarbonate levels on mortality in hemodialysis patients

BACKGROUND/AIMS: The optimal serum bicarbonate level is controversial for patients who are undergoing hemodialysis (HD). In this study, we analyzed the impact of serum bicarbonate levels on mortality among HD patients. METHODS: Prevalent HD patients were selected from the Clinical Research Center registry for End Stage Renal Disease cohort in Korea. Patients were categorized into quartiles according to their total carbon dioxide (tCO₂) levels: quartile 1, a tCO₂ of < 19.4 mEq/L; quartile 2, a tCO₂ of 19.4 to 21.5 mEq/L; quartile 3, a tCO₂ of 21.6 to 23.9 mEq/L; and quartile 4, a tCO₂ of ≥ 24 mEq/L. Cox regression analysis was used to calculate the adjusted hazard ratio (HR) and confidence interval (CI) for mortality. RESULTS: We included 1,159 prevalent HD patients, with a median follow-up period of 37 months. Kaplan-Meier analysis revealed that the all-cause mortality was significantly higher in patients from quartile 4, compared to those from the other quartiles (p = 0.009, log-rank test). The multivariate Cox proportional hazard model revealed that patients from quartile 4 had significantly higher risk of mortality than those from quartile 1, 2 and 3, after adjusting for the clinical variables in model 1 (HR, 1.99; 95% CI, 1.15 to 3.45; p = 0.01) and model 2 (HR, 1.82; 95% CI, 1.03 to 3.22; p = 0.04). CONCLUSIONS: Our data indicate that high serum bicarbonate levels (a tCO₂ of ≥ 24 mEq/L) were associated with increased mortality among prevalent HD patients. Further effort might be necessary in finding the cause and correcting metabolic alkalosis in the chronic HD patients with high serum bicarbonate levels.

The impact of blood flow rate during hemodialysis on all-cause mortality

BACKGROUND/AIMS: Inadequacy of dialysis is associated with morbidity and mortality in chronic hemodialysis (HD) patients. Blood flow rate (BFR) during HD is one of the important determinants of increasing dialysis dose. However, the optimal BFR is unclear. In this study, we investigated the impact of the BFR on all-cause mortality in chronic HD patients. METHODS: Prevalent HD patients were selected from Clinical Research Center registry for end-stage renal disease cohort in Korea. We categorized patients into two groups by BFR < 250 and ≥ 250 mL/min according to the median value of BFR 250 mL/min in this study. The primary outcome was all-cause mortality. RESULTS: A total of 1,129 prevalent HD patients were included. The number of patients in the BFR < 250 mL/min was 271 (24%) and in the BFR ≥ 250 mL/min was 858 (76%). The median follow-up period was 30 months. Kaplan-Meier analysis showed that the mortality rate was significantly higher in patients with BFR < 250 mL/min than those with BFR ≥ 250 mL/min (p = 0.042, log-rank). In the multivariate Cox regression analyses, patients with BFR < 250 mL/min had higher all-cause mortality than those with BFR ≥ 250 mL/min (hazard ratio, 1.66; 95% confidence interval, 1.00 to 2.73; p = 0.048). CONCLUSIONS: Our data showed that BFR < 250 mL/min during HD was associated with higher all-cause mortality in chronic HD patients.

Comparison of uremic pruritus between patients undergoing hemodialysis and peritoneal dialysis

BACKGROUND: Uremic pruritus is a common, but unpleasant, complication of end-stage renal disease. The uremic burden may differ between hemodialysis (HD) and peritoneal dialysis (PD) patients. This difference may also change the clinical characteristics of uremic pruritus between the 2 modalities. In this study, we investigated the uremic pruritus between patients on HD and PD. METHODS: A total of 425 HD and 223 PD patients from the Clinical Research Center registry in Korea were included. Patients were assessed for pruritus intensity, scratching activity, pruritus distribution, and frequency of pruritus-related sleep disturbance using the visual analog scale and questionnaire. RESULTS: The prevalence of uremic pruritus was higher in PD patients than that in HD patients (62.6% vs. 48.3%, P = 0.001). In the multivariable logistic analysis, PD treatment was significantly associated with the prevalence of uremic pruritus (odds ratio, 1.76; 95% confidence interval, 1.20-2.57, P = 0.004) after adjustment for clinical variables. The visual analog scale score, representing a subjective intensity of itchiness, was significantly higher in PD patients (PD 2.11 ± 2.32 vs. HD 1.65 ± 2.28, P = 0.013) compared with HD patients. The intensity of uremic pruritus was independently related with serum albumin levels (β = -0.143, P = 0.006) in HD patients and total weekly Kt/V (β = -0.176, P = 0.028) in PD patients. CONCLUSION: Our data demonstrate the difference in prevalence, intensity, and risk factors of uremic pruritus between HD and PD patients. These findings suggest that careful consideration for uremic pruritus might be needed in end-stage renal disease patients according to the dialysis modality.

Three-Years Outcome of Microdiscectomy via Paramedian Approach for Lumbar Foraminal or Extraforaminal Disc Herniations in Elderly Patients over 65 Years Old

OBJECTIVE: Lumbar foraminal or extraforaminal disc herniations (FEFDH) have unusual clinical features and higher incidence in elderly patients compared to usual intraspinal canal disc herniations. We evaluated the efficacy of microdiscectomy via paramedian approach for lumbar FEFDH in elderly patients over the age of 65. METHODS: Retrospective study was performed in 68 patients over the age of 65 (23 male and 45 female patients; 71.46±3.87 years) who underwent microdiscectomy via paramedian approach for unilateral lumbar FEFDH causing sciatica. The radiological factors including degree of slippage, presence of instability, disc height, and degree of disc degeneration; pain and functional status by the means of visual analogue scale score, Oswestry Disability Index score, and Macnab classification were analyzed preoperatively and during the postoperative follow-up period of 3 years to evaluate the efficacy of the surgical treatment. RESULTS: Pain and functional status improved according to short- and long-term follow-up evaluations after surgery. Radiological changes following surgery, which can be understood as structural deteriorations and deformations, did not represent patient condition. Nine patients underwent additional surgery due to sustained or recurring leg pain of aggravation of back pain, and fusion surgery was required for 3 patients. Degree of preoperative slippage was the only statistically significant factor related to additional surgery (p<0.05). CONCLUSION: Microdiscectomy via paramedian approach for FEFDH may be a good surgical alternative in elderly patients. Radiological changes after surgery did not show a concordance with patients' actual functional status. The excessive preoperative slippage tended to lead to unfavorable result after surgery and was associated with additional surgery.