Acetazolamide: A New Treatment for Visual Vertigo.

Visual vertigo is a disorder characterised by symptoms of dizziness, vertigo, unsteadiness, disorientation, and general discomfort induced by visual triggers. It is currently treated with vestibular rehabilitation therapy, with no effective pharmacotherapy available for treatment-resistant cases. The objective of this study was to evaluate the efficacy of oral acetazolamide in improving symptoms of visual vertigo. A comparative case series of adult patients clinically diagnosed with visual vertigo was conducted from January 1992 to May 2015. Patients without a full neurologic or otorhinolaryngologic work-up, negative magnetic resonance imaging (MRI), and an organic cause for their symptoms were excluded. The identified patients were then contacted by phone to complete a voluntary symptom survey. Main outcome was the subjective reported percentage in symptom improvement. Secondary outcomes were subjective improvement by symptom triggers. The participants were retrospectively divided into three groups based on their treatment with acetazolamide: currently on acetazolamide, terminated acetazolamide, or never initiated acetazolamide. Fifty-seven patients met the inclusion criteria and were willing to complete the phone survey (19 currently on acetazolamide, 27 terminated acetazolamide, and 11 never initiated therapy). Overall symptomatic improvement was reported by 18 (94.7%) patients currently on acetazolamide, 18 (66.7 %) who terminated acetazolamide, and 5 (45.5%) who never initiated therapy, varying significantly by group (p = 0.0061). Greatest improvement was reported in symptoms triggered by being a passenger in a car. These results show that acetazolamide has a positive association with improvement of symptoms of visual vertigo.

Mycobacterium chelonae Scleral Abscess After Intravitreal Ranibizumab Injection.

PURPOSE: To report a case of Mycobacterium chelonae scleral abscess after an intravitreal injection of ranibizumab. METHODS: A 54-year-old female received an intravitreal ranibizumab injection for diabetic macular edema. Two weeks postinjection, a scleral abscess developed at the injection site. The patient was treated with incision and drainage of the abscess, subconjunctival injection of amikacin, topical clarithromycin and amikacin, and oral clarithromycin. RESULTS: After 4 weeks of treatment, the inflammation and infection resolved, and the patient returned to best-corrected preinjection visual acuity. CONCLUSIONS: Injection-site scleral abscesses are very rare and serious complications of intravitreal injections. Once the abscess is drained, it is possible to identify the organism and treat the infection with appropriate combination antibiotic therapy.

Interplay of metallophilic interactions, π-π stacking, and ligand substituent effects in the structures and luminescence properties of neutral Pt(II) and Pd(II) aryl isocyanide complexes.

Packing interactions in the crystal structures of a series of cis-M(CNAr)(2)Cl(2) complexes (M = Pt, Pd; Ar = substituted phenyl) were examined and correlated with the luminescence properties of the Pt complexes. The structures of the PhNC and p-tolyl isocyanide complexes exhibit extended chains of metallophilic interactions with M···M distances of 3.24-3.25 and 3.34 Å, respectively, with nearly isostructural Pt and Pd compounds. Both structure types contain void channels running parallel to the M···M chains. The channels are 3-4 Å wide and vacant for the phenyl structures, while those in the p-tolyl structures are up to 7.6 Å wide and contain water. These channeled structures are stabilized by a combination of metallophilic bonding and aryl π-π stacking interactions. The Pt structure with 4-F substituents also features extended Pt···Pt chains, but with longer 3.79 Å distances alternating with shorter 3.37 Å contacts. Structures with 4-CF(3) and 4-OMe substituents exhibit mostly isolated dimers of M···M contacts. In complexes with 2,6-dimethylphenyl isocyanide, steric hindrance precludes any short M···M contacts. The primary effect of aryl substitution is to provide alternative packing motifs, such as CF(3)···π and CH(3)···π interactions, that either augment or disrupt the combination of metallophilic contacts and π-π stacking needed to stabilize extended M···M chains. Differences in the Pt and Pd structures containing 4-F and 4-OMe substituents are consistent with a higher driving force for metallophilic interactions for Pt versus Pd. The M-C and M-Cl bond distances indicate a slightly higher trans influence for aryl isocyanides bound to Pt versus Pd. The three extended Pt···Pt chain structures display luminescence assignable to (dσ*→pσ) excited states, demonstrating the existence of substantial orbital communication along the metal-metal chains. Face-indexing shows that the preferred crystal growth axis is along the metal-metal chains for the luminescent structures. Variable temperature structural studies showed that both M···M and π-π interactions contract upon cooling. Overall, this study suggests that synergy with π-π and other interactions is necessary to stabilize extended M···M chain structures. Thus, efforts to design functional materials based on metallophilic bonding must consider the full array of available packing motifs.