The Usefulness of a Simplified Navigation-Based Instrumentation for a Novice Surgeon in Primary Total Knee Arthroplasty: A Retrospective Analysis of a Randomized Controlled Trial

Background@#A novel simplified navigation-based instrumentation system has been developed. It simplifies the existing navigation system and facilitates convenient bone cutting by positioning the tracker on an existing cutting block without additional pin fixation. This study aimed to compare the outcomes of this newly developed simplified navigation-based instrumentation system in primary total knee arthroplasty (TKA) performed by a novice surgeon with those of conventional surgical techniques. @*Methods@#From January 2020 to July 2020, 67 knees that underwent primary TKA using the ExactechGPS TKA Plus (group A) were compared to 68 knees that underwent primary TKA using a conventional technique (group B). All patients had a minimum follow-up of 24 months. The operative details such as tourniquet time were investigated. Postoperative hip-knee-ankle (HKA) angle and component position angles in the coronal and sagittal planes (α, β, γ, and δ angles) were evaluated. The outlier rates were compared between the groups as those lying outside ± 3°. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, the Western Ontario and McMaster Universities Osteoarthritis Index for pain and function, and range of motion were compared. @*Results@#There was no statistically significant difference in average tourniquet time between the groups (74.3 vs. 70.3 minutes, p = 0.061). Outlier rates for HKA angle (7.5% vs. 23.5%, p = 0.010) and β angle (1.5% vs. 22.1%, p < 0.001) in group A were significantly lower than those in group B. There were no significant differences in clinical outcomes between the groups. @*Conclusions@#Primary TKA performed by a novice surgeon using a simplified navigation-based instrumentation system did not significantly increase the operation time, and more accurate lower extremity mechanical alignment and tibial component alignment in the coronal plane could be obtained.

Comparison of 18F FDG-PET and CT/MRI for the Diagnosis of Cervical Lymph Node Metastasis in Head and Neck Cancer: A Level-by-Level Based Study / 대한핵의학회잡지

PURPOSE: Cervical lymph node metastasis is the most important factor of the prognosis and therapeutic planning in head and neck cancer. With increasing interest of minimally invasive neck surgery, more accurate preoperative assessment of cervical lymph node becomes more essential. We evaluated the diagnostic accuracy of 18F FDG-PET in the assessment of lymph node metastasis in patients with primary head and neck cancer and compared the results with those of CT/MRI. MATERIALS AND METHODS: Thirty-two patients (M/F=27/5, 56 +/- 10yr) with biopsy proven head and neck cancer (16 supraglottic cancer, 9 tongue cancer, 7 others) underwent FDG-PET and CT/MRI (25/7) within 1 month before neck dissection. Based on lymph node level, the diagnostic sensitivity and specificity of FDG PET and CT/MRI for the metastasis of cervical lymph node were compared. RESULTS: Of 153 lymph node levels dissected in 32 patients, 32 lymph node levels of 19 patients were positive for metastasis by histopatholologic examination. The overall sensitivity and specificity of FDG-PET were 88% (28/32) and 93% (113/121), whereas those of CT/MRI were 56% (18/32) (p=0.002) and 92% (112/121), respectively. The diagnostic sensitivity and specificity of FDG-PET were different according to location of lymph node levels, and those of ipsilateral level II were lower than those of other levels. CONCLUSION: FDG-PET is more sensitive in detecting metastatic cervical lymph node in head and neck cancer than CT/MRI. FDG-PET might be useful in guiding the extent of neck dissection.

Event-Related Functional Magnetic Resonance Imaging in Post-Traumatic Stress Disorder / 신경정신의학

OBJECTIVE: Symptom provocation paradigms using event-related functional magnetic resonance imaging(fMRI) can be an important tool to visualize neuroanatomic correlates of PTSD symptoms. The purpose of this study is to measure regional changes of brain upon exposure to fear stimulus and elucidate the probable relation between signal changes and fear response in PTSD. METHOD: Event-related fMRI was performed during a task where traffic accident-related photos and checkerboards were presented in 9 women with PTSD and 9 woman normal controls in unpredictable order. MRI data were acquired on a 1.5 T GE vision system with a head volume coil. Stimuli were presented on a mirror mounted on the head coil. A total of 200 functional images were taken during a 10-minute scanning session. TR was 3 seconds and inter-stimulus time was varing 4.5 to 11.5 seconds. Data was analyzed using SPM99. RESULTS: In PTSD group, the fear conditions versus the neutral conditions showed activations in both occipital cortex, both fusiform gyrus, left parietal lobule, both insula, right cerebellar tonsil, right putamen, right claustrum, but deactivations in both prefrontal gyrus(p<0.001). In normal control group, activation were found for the fear conditions as compared with the neutral conditions in left fusiform gyrus, both occipital cortex, left parietal lobule, right frontal lobule(p<0.001). CONCLUSIONS: Emotion provocation paradigm using event-related functional magnetic resonance imaging can be applied to illustrate fear response mechanism in PTSD. The result suggests that insula, limbic lobe, cerebellum may play a role in mediating fear response in PTSD.

Endocrinological Results of the Transsphenoidal Microsurgery for Cushing's Disease

OBJECTIVE: We analyzed the clinical and endocrinological results of the transsphenoidal microsurgery for ACTH secreting pituitary adenomas. MATERIALS AND METHODS: From October 1995 to August 2000, 18 patients underwent transsphenoidal microsurgery for Cushing's disease. We analyzed the surgical results of 17 patients, one patient who was previously operated from other hospital was excluded. Age of the patients were 18 to 61 years old(mean 37.7), male to female ratio was 1: 3.3, and follow-up period was 3 to 50 months(mean 20.3). The selection of candidates for transsphenoidal exploration was based on endocrinologic criteria. Magnetic resonance imaging was the preferred radiologic test. Selective inferior petrosal sinus sampling of adrenocorticotropic hormone futher refined the diagnosis when endocrinologic and radiologic procedures were not definitive. RESULTS: Results of the preoperative endocrinological test were: level of serum ACTH 29.4 to 225ng/dL(mean 93.88ng/dL); serum cortisol 11.9 to 47.5ng/dL(mean 27.49ng/dL); 24-hour urine free cortisol 235 to 1019ng/day(mean 571.0ng/day). Inferior petrosal sinus sampling for ACTH was performed in 11 patients and all were confirmed by Cushing's disease and we could predict the laterality of the tumor in 9 of 11 patients. We performed transsphenoidal selective adenomectomy in 5 patients, adenomectomy and subtotal hypophysectomy in 2 patients, adenomectomy and partial hypophysectomy in 9 patients, and in the remaining one patient, hemihypophysectomy followed by total hypophysectomy due to remission failure. Fifteen of 17 patients(88.2%) showed endocrinological remission. Glucocorticoid replacement therapy was performed in all the patients who showed remission for 1 to 24 months(mean 5.9 months), and 6 patients received steroid over 6 months. CONCLUSION: We conclude that the direct demonstration of a tumor in the pituitary gland by MRI is the most important and definitive diagnostic tool and the location of a mass should be confirmed with increased level of ACTH by the inferior petrosal sinus sampling. Transsphenoidal microsurgery is effective treatment modality for Cushing's disease and the immediate postoperative evaluation of the surgical resection of the tumor is very important. The patients should show hypocortisolism, decreased, subnormal serum ACTH and cortisol levels and 24-hours urine free cortisol. We performed 18 transsphenoidal microsurgery for Cushing's disease in 17 patients and 15 patients(88.2%) showed endocrinological remission.