Structure of choline chloride-carboxylic acid deep eutectic solvents by wide-angle X-ray scattering and DFT calculations.

Choline chloride (ChCl)-carboxylic acid deep eutectic solvents (DESs) are promising green solvents for lignocellulose pretreatment, de-aromatization of gasoline, battery recycling, etc. Micro interactions determine the physical properties of DESs, such as melting point, viscosity, and solubility. In the present work, the structures of choline chloride/formic acid (FA) and choline chloride/acetic acid (AA) with a 1 : 2 molar ratio were investigated by wide-angle X-ray scattering, empirical potential structure refinement (EPSR) and density functional theory (DFT) calculations. Reduced density gradient (RDG) and atoms in molecules (AIM) show that hydrogen bonds and carbon-hydrogen bonds exist in choline chloride-carboxylic acid DESs. EPSR modelling based on the gauche choline cation model reveals the interactions between DES components. Cl- plays an important role in maintaining the structural stability of choline chloride-carboxylic acid DESs, by participating in the formation of hydrogen bonds, carbon-hydrogen bonds, and acting as a bridge for indirect interaction, including between choline cations and carboxylic acid molecules. Molecular size and steric hindrance elucidate the formation of different sizes of clusters (≤10 molecules) and chains (≤5 molecules) in DESs. Spatial density functions show that formic acid and acetic acid have a strong orientational preference. The strong interaction between Ch+ and FA and the existence of the Cl- bridge significantly destroyed the lattice structure of ChCl, resulting in the melting point of ChClFA (<-90 °C) being lower than that of ChClAA (-8.98 °C). This fundamental understanding of the structure will enable the development of green, economical, and nontoxic choline chloride-carboxylic acid DESs.

Cavitation with low-energy sonication during focused ultrasound thalamotomy for a patient with tremor-dominant Parkinson's disease: a potential risk.

We report a patient with tremor-dominant Parkinson's disease who had a mild cavitation bioeffect during magnetic resonance-guided focused ultrasound thalamotomy. During the aligning phase with low-energy sonication, cavitation caused mild dysarthria and paresthesia, prompting treatment cessation. At the same time, tremor and rigidity improved. MRI revealed extensive high-intensity lesions in the thalamus 1 day after the procedure followed by steroid infusion, which resulted in resolution of adverse events. Tremor and rigidity improved 1.5 years after the procedure. Although cavitation can relieve tremors and rigidity, it should be carefully monitored due to potential permanent adverse events by unpredictable and unknown behaviors.

Exacerbation of non-steroidal anti-inflammatory drug-induced enteropathy in C-C chemokine receptor type 7-deficient mice.

BACKGROUND AND AIM: Non-steroidal anti-inflammatory drugs (NSAIDs) induce intestinal enteropathy and the pathophysiology is related to immune-mediated mechanisms. We aimed to investigate the role of C-C chemokine receptor type 7 (CCR7) which regulates immune cell migration in NSAID-induced enteropathy. METHODS: Injury of the small intestine was evaluated 24 h after the subcutaneous injection of indomethacin in CCR7-deficient (Ccr7-/- ) and wild-type (WT) mice. The cellular profile and cytokine production in intestinal cells were analyzed. Indomethacin-induced enteropathy was evaluated in mice adoptively transferred with CD103+ dendritic cells (DCs) from Ccr7-/- or WT mice. RESULTS: Indomethacin induced more severe intestinal injury in Ccr7-/- mice than in WT mice. The major inflammatory cytokines were not increased and the proportion of regulatory T cells following indomethacin injection was not decreased in Ccr7-/- mice compared with WT mice. The expression of interleukin (IL)-22 binding protein (IL-22BP), which inhibits IL-22 activity, was significantly higher in CD103+ DCs from Ccr7-/- mice than those from WT mice. Mice adoptively transferred with CD103+ DCs isolated from Ccr7-/- mice exhibited more severe intestinal injury following indomethacin injection compared with those adoptively transferred with CD103+ DCs of WT mice. Ccr7-/- mice injected with indomethacin showed a significant reduction in regenerating islet-derived 1 (Reg1) mRNA expression, which is regulated by IL-22, in intestinal epithelial cells. CONCLUSIONS: C-C chemokine receptor type 7 deficiency exacerbated NSAID-induced enteropathy in association with an altered phenotype of CD103+ DCs that produces IL-22BP. CCR7 contributes to protect the small intestine from NSAID-induced mucosal injury.

Different properties of two types of red fluorescent proteins in octocoral, Scleronephthya spp. as Akane families.

We report the different properties of two types of red fluorescent proteins (RFP), undescribed species, extracted from two octocorals, Scleronephthya sp. 1 (S. sp. 1) and S. sp, 2 (Alcyonacea, Nephtheidae). S. sp. 1, named Alc-Orange, emits strong green emission at 492 nm and weak red emission at 590 and 630 nm when excited at 449 and 574 nm, respectively. S. sp. 2, LS-Red, emits strong deep red at 642 nm and weak green at 480 and 510 nm when excited at 574 nm and 434 nm, respectively. LS-Red has a very large Stokes shift of about 208 nm emitting at 642 nm when excited at 434 nm. Interestingly, LS-Red shows some emissions at 480 (blue emission), 514 (green emission), 563 (orange emission), and 642 nm (deep red emission) continuously at pH 7.5, which means multicolored fluorescence protein by one excitation at 434 nm. In pH dependence of fluorescence of Alc-Orange (pH 13 to 3.5), no relation between 'green and red FPs' was observed, whereas LS-Red showed the interconversion between 'green and red forms' depending on pH (11.5 to 4.5).

[A case of eosinophilic gastroenteritis caused after the use of Seprafilm®].

Eosinophilic gastroenteritis is a fairly uncommon condition. It has been suggested that allergic reactions may have played a role in the development of this illness. The case of a 66-year-old woman who had a total hysterectomy due to a right ovarian tumor is described here. At this operation, a sodium hyaluronate carboxymethylcellulose bioresorbable membrane (Seprafilm®) was used. She was admitted to our hospital 47 days after the operation with abdominal pain. Laboratory data indicated elevated WBC (29450/µl) and eosinophilia (69.2%), and CT scan showed thickening of intestinal wall and ascites around there. Ascites cytology showed a significant increase of eosinophils (94.0%). She began taking oral steroids after being diagnosed with eosinophilic gastroenteritis, and her symptoms improved quickly. Despite the fact that Seprafilm® was thought to be a reliable and safe tool, it was suggested that a foreign body reaction to Seprafilm® could lead to eosinophilic gastroenteritis.

Magnetic Resonance-Guided Focused Ultrasound Thalamotomy for Focal Hand Dystonia: A Pilot Study.

BACKGROUND: The efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy for the treatment of focal hand dystonia (FHD) is not well known. OBJECTIVE: We aimed to prospectively investigate the efficacy of MRgFUS thalamotomy for the treatment of FHD. METHODS: We performed MRgFUS thalamotomy of the ventro-oral (Vo) nucleus in 10 patients with FHD. We evaluated the scores of the Writer's Cramp Rating Scale (WCRS, 0-30; higher scores indicating greater severity), Tubiana Musician's Dystonia Scale (TMDS, 0-5; lower scores indicating greater severity), and Arm Dystonia Disability Scale (ADDS, 0%-100%; lower scores indicating greater disability) at baseline and 3 and 12 months post-treatment. RESULTS: WCRS, TMDS, and ADDS scores significantly improved from 6.3 ± 2.7, 1.4 ± 0.5, and 58.7% ± 14.3% at baseline to 1.6 ± 3.1 (P = 0.011), 5.0 ± 0 (P = 0.0001), and 81.6% ± 22.9% (P = 0.0229) at 12 months, respectively. There was one prolonged case of dysarthria at 12 months. CONCLUSION: We show that MRgFUS Vo-thalamotomy significantly improved FHD. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Correction: Local structure of a highly concentrated NaClO4 aqueous solution-type electrolyte for sodium ion batteries.

Correction for 'Local structure of a highly concentrated NaClO4 aqueous solution-type electrolyte for sodium ion batteries' by Ryo Sakamoto et al., Phys. Chem. Chem. Phys., 2020, 22, 26452-26458, DOI: 10.1039/D0CP04376A.

Ion hydration and association in aqueous potassium tetrahydroxyborate solutions.

Potassium tetrahydroxyborate solution is a significant material in the borate solution family, but there is limited knowledge about hydration structures and interactions of K+, [B(OH)4-], and water. In this study, the X-ray diffraction measurements of potassium tetrahydroxyborate solutions have been made. The experimental structure factors are subjected to Empirical Potential Structure Refinement (EPSR) modeling to reveal the details of ion hydration and association in the aqueous solutions. This study shows that the O(W)-O(W) distance of water in the studied solutions ranges from 2.82 to 2.76 Å with a coordination number that ranges from 4.7 ± 1.4 to 3.1 ± 1.3 when the value of the water-salt molar ratio (WSR) is decreased from 30 to 6. The addition of ions slightly affects the tetrahedral structure of water even when the concentration of ions is high. The first hydration distance of K+ remained at ∼2.67 Å, whereas the value of the coordination number (CN) decreased from 5.4 ± 1.3 to 3.9 ± 1.5 when the concentration of the borate solution was increased. The hydration ability of K+ was weak and almost did not have a fixed local hydration structure. The pair distribution function (PDF) of gB-O(W)(r) shows that [B(OH)4-] has a broad hydration distance from 2.9 to 5.4 Å because of the complex interactive relationship between K+, [B(OH)4-] and water. There is a competitive hydration between K+ and [B(OH)4-]. Both the X-ray diffraction and DFT-based calculations confirm that the main species is monodentate contact ion pairs when WSR = 30, bidentate contact ion pairs when WSR = 14, and triple contact ion pairs when WSR = 6. These results will provide a new understanding about potassium tetrahydroxyborate solution.

Magnetic resonance-guided focused ultrasound for mesial temporal lobe epilepsy: a case report.

BACKGROUND: We report the first case of transcranial magnetic resonance-guided focused ultrasound (MRgFUS) for mesial temporal lobe epilepsy (MTLE). CASE PRESENTATION: The target was located 20 mm lateral from the midline and 15 mm above the skull base (left hippocampus). Despite the application of maximal energy, the ablation temperature did not exceed 50 °C, probably because of the low number of effective transducer elements with incident angles below 25 degrees. The skull density ratio was 0.56. Post-operative magnetic resonance imaging did not reveal any lesion and the patient remained almost seizure-free for up to 12 months. CONCLUSIONS: This preliminary case report suggests that MRgFUS may be effective for treating cases of MTLE. Therefore, the safety and feasibility of MRgFUS should be evaluated in future studies with larger numbers of participants and longer follow-up duration.

Endoscopic alterations in Peyer's patches in patients with ulcerative colitis: A prospective, multicenter study.

BACKGROUND AND AIM: Peyer's patches (PPs) play a major role in intestinal mucosal immunity; however, their role in ulcerative colitis (UC) is not well investigated. We evaluated endoscopic features of PPs on narrow-band imaging with magnifying endoscopy (NBI-ME) and investigated their association with clinical factors. METHODS: We prospectively recruited 105 patients with UC, 18 with Crohn's disease, 16 with disease control, and 33 healthy control subjects at three institutions from 2014 to 2017. NBI-ME images of the villi of PPs were evaluated according to the Villi Index, and patients were divided into the Villi Index low (L) and high (H) types. The 1-year sustained clinical remission rate was evaluated between L-type and H-type PPs in patients with UC. RESULTS: The proportions of patients with H-type PPs were significantly higher among UC, Crohn's disease, and disease control patients than among healthy control patients (P = 0.0125, 0.018, 0.0007). In UC, age, gender, endoscopic score, and extent of disease involvement were not significantly different between L-type and H-type PPs, whereas the sustained clinical remission rate was significantly higher in L-type PPs than in H-type PPs (88% [57/65] vs 65% [17/26], P = 0.019). Multivariate analysis revealed that the L type of PPs was a significant factor for sustained clinical remission (odds ratio 3.8, 95% confidence interval 1.1-12.9, P = 0.033). CONCLUSIONS: Patients with UC showed endoscopic alterations in PPs on NBI-ME, and highly altered appearance of PPs can be associated with a high risk of clinical relapse in patients with UC.

The structural elucidation of aqueous H3BO3 solutions by DFT and neutron scattering studies.

The micro-structure of aqueous boric acid (H3BO3) solutions is of broad interest in earth sciences, geochemistry, material science, as well as chemical engineering. In the present study, the structure of aqueous H3BO3 solutions was studied via neutron scattering with 2H and 11B isotope labelling combined with empirical potential structure refinement (EPSR) modelling. In aqueous H3BO3 solutions, B(OH)3 is the dominant borate species. Density function theory (DFT) calculations show that the boron hydroxyl has a lower electrostatic potential (ESP), which makes B(OH)3 a relatively weakly hydrated, compared with the bulk water. In the 0.95 mol L-1 H3BO3 solution at 298 K (saturated), ∼18 water molecules enter the hydration sphere of B(OH)3 with the hydration distance (B-O(W)) of 3.75 Å, while only 4.23 of them hydrate with H3BO3 as the hydrogen bond (H-bond) acceptor or H-bond donor. Both neutron scattering and DFT calculations for 2B(OH)3·6H2O clusters at the ωB97XD/6-311++g(3df,3pd) basis level show that B(OH)3 forms molecular clusters in bidentate contact molecular pairs (BCMP), mono-dentate molecular pairs (MCMP), solvent-shared molecular pairs (SMP), and parallel solvent-shared molecular pairs (PSMP) in aqueous solutions. Their relative contents are both concentration- and temperature-sensitive. BCMP with the B-B distance of ∼4.1 Å is the dominant molecular pair in the aqueous solutions. Relatively less content and van der Waals interactions stabilized PSMP, with a B-B distance of ∼3.6 Å between the two parallel layers, which is a crucial species for the crystallization of H3BO3 from aqueous solution.

Local structure of a highly concentrated NaClO4 aqueous solution-type electrolyte for sodium ion batteries.

Aqueous Na-ion batteries with highly concentrated NaClO4 aq. electrolytes are drawing attention as candidates for large-scale rechargeable batteries with a high safety level. However, the detailed mechanism by which the potential window in 17 m NaClO4 aq. electrolyte was expanded remains unclear. Therefore, we investigated the local structure around a Na+ ion or a ClO4- ion using X-ray diffraction combined with empirical potential structure refinement (EPSR) modelling and Raman spectroscopy. The results showed that in 17 m NaClO4 aq. electrolyte, most of the water molecules were coordinated to Na+ ions and few free water molecules were present. The 17 m NaClO4 aq. electrolyte could be interpreted as widening the potential window because almost all water molecules participated in hydration of the Na+ ions.

Magnetic resonance-guided focused ultrasound ablation of hypothalamic hamartoma as a disconnection surgery: a case report.

We report the case of a patient with hypothalamic hamartoma (HH) who was successfully treated with magnetic resonance-guided focused ultrasound (MRgFUS) for ablation as a disconnection surgery. A 26-year-old man with gelastic epilepsy had been diagnosed with HH at 3 years of age, and antiepileptic drugs were administered due to worsening episodes. Magnetic resonance imaging showed a sessile parahypothalamic hamartoma and MRgFUS ablation was performed, creating an oval-shaped lesion at the boundary area of the HH. Dramatic improvements in seizure symptoms were noted, and he was seizure-free on decreased antiepileptic drugs without any adverse events over the 1-year follow-up period.

A Randomized Trial of Focused Ultrasound Thalamotomy for Essential Tremor.

BACKGROUND: Uncontrolled pilot studies have suggested the efficacy of focused ultrasound thalamotomy with magnetic resonance imaging (MRI) guidance for the treatment of essential tremor. METHODS: We enrolled patients with moderate-to-severe essential tremor that had not responded to at least two trials of medical therapy and randomly assigned them in a 3:1 ratio to undergo unilateral focused ultrasound thalamotomy or a sham procedure. The Clinical Rating Scale for Tremor and the Quality of Life in Essential Tremor Questionnaire were administered at baseline and at 1, 3, 6, and 12 months. Tremor assessments were videotaped and rated by an independent group of neurologists who were unaware of the treatment assignments. The primary outcome was the between-group difference in the change from baseline to 3 months in hand tremor, rated on a 32-point scale (with higher scores indicating more severe tremor). After 3 months, patients in the sham-procedure group could cross over to active treatment (the open-label extension cohort). RESULTS: Seventy-six patients were included in the analysis. Hand-tremor scores improved more after focused ultrasound thalamotomy (from 18.1 points at baseline to 9.6 at 3 months) than after the sham procedure (from 16.0 to 15.8 points); the between-group difference in the mean change was 8.3 points (95% confidence interval [CI], 5.9 to 10.7; P<0.001). The improvement in the thalamotomy group was maintained at 12 months (change from baseline, 7.2 points; 95% CI, 6.1 to 8.3). Secondary outcome measures assessing disability and quality of life also improved with active treatment (the blinded thalamotomy cohort)as compared with the sham procedure (P<0.001 for both comparisons). Adverse events in the thalamotomy group included gait disturbance in 36% of patients and paresthesias or numbness in 38%; these adverse events persisted at 12 months in 9% and 14% of patients, respectively. CONCLUSIONS: MRI-guided focused ultrasound thalamotomy reduced hand tremor in patients with essential tremor. Side effects included sensory and gait disturbances. (Funded by InSightec and others; ClinicalTrials.gov number, NCT01827904.).

Usefulness of intestinal real-time virtual sonography in patients with inflammatory bowel disease.

BACKGROUND AND AIM: Transabdominal ultrasonography (US) examination for the intestine is often difficult, and its precedence for intestinal examination depends on accessibility to experienced ultrasonographers. Real-time virtual sonography (RVS) assists examination of US as a fusion method by synchronizing US images with pre-captured computed tomography or magnetic resonance images. We aimed to evaluate the feasibility to use RVS for the examination of the intestine. METHODS: The time to scan three parts of the intestine was compared between conventional US and RVS in seven participants without intestinal diseases. Whether RVS accurately synchronized US images with reference images of intestinal target lesions was judged in 20 patients with inflammatory bowel disease. RESULTS: Examination time to scan the ascending colon and the ileocecum using intestinal RVS was significantly shorter than that using conventional US alone (36.7 vs 50.0 s [P = 0.0313] and 35.4 vs 66.4 s [P = 0.0156], respectively) in participants without intestinal diseases. Well-synchronized US images of the intestinal lesions, such as stenosis, with reference computed tomography/magnetic resonance images were obtained by RVS in all the lesions in the fixed parts of the colon (ascending and descending colon), and images of nine lesions in 12 lesions (75%) were well synchronized in the unfixed part of the intestine in Crohn's disease patients. CONCLUSION: Real-time virtual sonography significantly reduced the examination time of intestinal US. Intestinal RVS can help the ultrasonographer to guide the US probe to detect and monitor intestinal lesions by synchronizing reference images, especially in inflammatory bowel disease patients (UMIN Clinical Trials Registry number: UMIN000011571).

Nanoscale dynamics of water confined in ordered mesoporous carbon.

The single particle dynamics of water confined within two ordered mesoporous carbon matrices was investigated in the temperature range from 290 K to 170 K by quasielastic neutron scattering using three high resolution neutron spectrometers. Thus, it was possible to investigate the mobility of water confined in model hydrophobic cavities at the nanoscale. Models developed for the nanoscale dynamics of supercooled water and water confined within hydrophilic matrices were able to describe the collected data but remarkable differences with analogous silica confined matrices were observed in these carbon samples. A significant fraction of the water molecules was immobile on the nanosecond timescale, even at room temperature. As the temperature was lowered, the mobility of the water molecules slowed down, but the strongly non-Arrhenius behavior observed in bulk water and for fully hydrated hydrophilic confinement was absent, which indicates frustration of the hydrogen bond network formation. The obtained results were relevant for applications of mesoporous carbon materials.

B(OH)4- hydration and association in sodium metaborate solutions by X-ray diffraction and empirical potential structure refinement.

X-ray diffraction is used to study the structure of aqueous sodium metaborate solutions at salt concentrations of 1, 3, and 5 (oversaturated) mol dm-3. The X-ray structure factors are subjected to empirical potential structure refinement (EPSR) modelling to extract the individual site-site pair correlation functions, the coordination numbers, and the spatial density functions (three-dimensional structure) of ion hydration and association as well as solvent water in the borate solutions. The sodium ion is surrounded on average by (5.4 ± 0.7), (4.6 ± 1.0), and (3.7 ± 1.2) water molecules at 1, 3, and 5 mol dm-3, respectively, with the Na-O (H2O) distance of 2.34 Å. The decrease in hydration number of the sodium ion is compensated by direct binding of the oxygen atom of the borate ion, B(OH)4-, with the average coordination number of (0.2 ± 0.5), (1.0 ± 0.8), and (2.1 ± 1.3) at the Na-O(B) distance of 2.34 Å to keep the octahedral hydration shell of the sodium ion. The average number of water molecules around the borate ion is (13.9 ± 1.8), (14.2 ± 1.8), and (16.1 ± 2.4) per borate ion with increasing salt concentration with the B-O(H2O) distance of 3.72 Å. The number of nearest-neighbour water molecules around a central water molecule in a solvent decreases as (4.8 ± 1.2), (3.8 ± 1.1), and (2.8 ± 1.1) with an increase in salt concentration with the O(H2O)-O(H2O) distance of 2.79 Å. The Na+-B(OH)4- ion association is characterized by the Na-O(B) and Na-B pair correlation functions. The Na-B interactions are observed at 3.00 Å as a shoulder and 3.57 Å as a main peak in the site-site pair correlation function, suggesting two occupancy sites of Na+ with one for the edge-shared bidentate bonding and the other for the corner-shared monodentate bonding. The total number of Na-B interactions at 3.00 and 3.57 Å is consistent with that of the Na-O(B) interactions. The detailed three-dimensional structure of the ion hydration and association is visualized as a function of salt concentration. The structure and stability of [NaB(OH)4(H2O)6]0 clusters are further investigated by DFT calculations, and the most likely structure is proposed and cross-checked.

A neutron spin echo study of low-temperature water confined in the spherical silica pores of SBA-16.

The dynamic properties of heavy water (D2O) and light water (H2O) confined in porous silica SBA-16 were studied over a temperature range of 210-290 K by neutron spin echo measurements. SBA-16 has predominant spherical pores (7.1 nm in pore size), channels interconnecting the spherical pores, and micropores (corona). The coherent intermediate scattering function on D2O filled SBA-16 showed the rotational dynamics of confined water without significant translational motion over the temperature range measured. This finding is due probably to collective entities of water due to cooperativity of hydrogen-bonds among water molecules in SBA-16 pores. The relaxation time of the collective entities followed the Vogel-Fulcher-Tammann relation at temperatures down to the freezing temperature of 235 K, suggesting a behavior of fragile water in the spherical pore. A comparison with previous NSE measurements of D2O in MCM-41 showed that the collective entities of water in the SBA-16 spherical pores have higher rotational mobility than those in the MCM-41 cylindrical pores. On the other hand, the incoherent intermediate scattering function on H2O filled SBA-16 revealed the translational motion of individual water molecules in the collective entities. It has been found that water in micropores is not frozen and is mobile down to 210 K from data of both D2O and H2O in SBA-16. Phase changes of various water confined in SBA-16 with decreasing and increasing temperatures are discussed based on the obtained dynamic properties.

Microhydration of BH4-: Dihydrogen Bonds, Structure, Stability, and Raman Spectra.

Hydridic-to-protonic interactions in unconventional dihydrogen bonding influence the structure, reactivity, and selectivity in solution and in the solid state. In this study, the structure, stability, and Raman spectra of BH4- hydrated clusters, [BH4(H2O)n]- (n = 1-8, 10, 12, 14, 16) are systematically investigated using density functional theory (DFT) at the wB97XD/6-311++g(3df,3pd) basis set level. The successive microhydration process is described to illustrate in detail the changes in dihydrogen bonding with increasing hydration cluster size. The results of DFT calculations indicate that seven or eight water molecules hydrate BH4- with a total of 12 dihydrogen bonds in the tetrahedral edge or tetrahedral corner forms, and a maximum of six water molecules in the tetrahedral-edge form. Raman spectra of [BH4(H2O)n]- show a blue shift in the B-H stretching band due to hydration. Car-Parrinello molecular dynamics simulations verify strong BH4- water interactions. The hydration number of BH4- is 6.7, with a hydration B-O(W) distance of 3.40 Å, and each hydrogen in BH4- bonds with 2.66 hydrogen atoms from water.

Comparison of Midterm Outcomes of Minimally Invasive Computer-Assisted vs Minimally Invasive Jig-Based Total Knee Arthroplasty.

BACKGROUND: Minimally invasive surgery (MIS) has perceived advantages in the early postoperative stage for total knee arthroplasty (TKA). It is not clear whether the improved radiographic alignment achieved by computer-assisted navigation surgery (CAS) improves midterm clinical outcomes. The aim of this study was to compare patient outcomes of MIS TKA performed with and without CAS after a minimum follow-up of 7 years. METHODS: Between 2007 and 2009, 50 patients underwent CAS and MIS TKA, and 50 patients underwent jig-based MIS TKA in this prospective study. Ninety-six patients were evaluated after a mean follow-up of 7.7 years, and clinical and radiological evaluations were performed. RESULTS: Midterm results demonstrated that the Knee Society knee score, function score, and range of motion were comparable in the 2 groups. The percentage of patients with the mechanical axis within ±3° of neutral was significantly higher in the CAS group than in the jig-based group (94% vs 79%, respectively; P = .038). No knees had loosening after TKA. However, 1 patient in the CAS group demonstrated late infection 4 years postoperatively. CONCLUSION: CAS did not improve midterm outcomes after MIS TKA compared with jig-based surgery, although CAS reduced outliers in coronal alignment.