Comparison of two techniques in posterior lens dislocations: Scleral suture fixation vs. modified Yamane intrascleral lens fixation.

PURPOSE: To compare the use of Yamane flanged intrascleral haptic fixation and scleral suture fixation (SSF) techniques in combination with pars plana vitrectomy (PPV) for treatment of posterior lens dislocations. METHODS: Patients who underwent PPV and scleral fixated IOL implantation due to subluxation/luxation of the crystalline lens/intraocular lens (IOL) were included in this retrospective study. The Yamane group included patients who underwent Yamane flanged intrascleral haptic fixation technique, while the SSF group consisted of patients who underwent conventional SSF. All patients underwent comprehensive ophthalmologic examinations preoperatively and postoperatively. Intraoperative and postoperative complications were recorded. RESULTS: The Yamane group comprised of 39 eyes of 39 patients, and the SSF group included 35 eyes of 35 patients. Postoperative complications included hyphema (Yamane group: 2/39 (5.1%); SSF group: 0/35 (0%)) IOL decentration (Yamane group: 5/39 (12.8%); SSF group: 0/35 (0%)), corneal edema (Yamane group: 4/39 (10.2%); SSF group: 0/35 (0%)) cystoid macular edema (CME) (Yamane group: 1/39 (2.5%); SSF group: 3/35 (8.5%)) and retinal detachment (Yamane group: 1/39 (2.5%); SSF group: 1/35 (28.5%). The mean surgery time was significantly lower in the Yamane group compared with the SSF group (P<0.001). No cases of hypotony, conjunctival erosion, haptic exposure or endophthalmitis were encountered throughout follow-up. CONCLUSION: SSF remains a safe and effective technique for management of posterior lens dislocations. The Yamane intrascleral IOL fixation technique is an effective alternative to conventional SSF, which has a relatively steep learning curve. Postoperative complications, including IOL tilt and decentration, may be experienced in the initial cases.

Observation of a martensitic structural distortion in V, Nb, and Ta.

Thermal-expansion measurements of the Group 5 elements V, Nb, and Ta reveal a structural distortion below 300 K. Data for single-crystalline Nb and Ta display anisotropic thermal expansion, martensitic in character, that is inconsistent with cubic crystal structures at low temperature. Published results on V show similar behavior. Interstitial impurities suppress the transition.

Geomicrobiology of subglacial ice above Lake Vostok, Antarctica.

Data from ice 3590 meters below Vostok Station indicate that the ice was accreted from liquid water associated with Lake Vostok. Microbes were observed at concentrations ranging from 2.8 x 10(3) to 3.6 x 10(4) cells per milliliter; no biological incorporation of selected organic substrates or bicarbonate was detected. Bacterial 16S ribosomal DNA genes revealed low diversity in the gene population. The phylotypes were closely related to extant members of the alpha- and beta-Proteobacteria and the Actinomycetes. Extrapolation of the data from accretion ice to Lake Vostok implies that Lake Vostok may support a microbial population, despite more than 10(6) years of isolation from the atmosphere.

Coupling Analysis of Fetal and Maternal Heart Rates via Transfer Entropy Using Magnetocardiography.

Recent studies have shown that occasional short term coupling between fetal and maternal cardiac systems occurs. Fetal magnetocardiography (fMCG) is a non-invasive technique that records the magnetic fields associated with the electrical activity of the fetal heart through sensors placed over the maternal abdomen. The fMCG allows accurate estimation of fetal heart rates (fHR) due to its high signal-to-noise ratio (SNR) and temporal resolution. In this study, we analyzed couplingbetween fHR and maternal heart rates (mHR) using Transfer Entropy (TE). TE determines coupling between two variables by quantifying the information transferred between them in both directions. In this work, we used 74 fMCG recordings to compute TE in both directions over 1-minute disjoint time windows (TW). We examined the effect of fetal movement (FM) as a factor of influence on the TE analysis. We identified 21 subjects with FM during the recording and separated them into two gestational age (GA) groups (GA1<32 and GA2≥32 weeks). Next, TE values were compared between TWs containing non- FM with TWs containing FM using Wilcoxon Signed-Rank test. In addition, we compared TE calculations for non-FM segments obtained from the 74 subjects using Rank-Sum test in the two GA groups. Our results showed that TE values from TWs containing FM are not significantly different than those computed for TWs of non-FM. In both directions, we found that TE values obtained from the 74 subjects did not show any significant difference between GA1 and GA2 which is consistent with previous studies. Our study suggests that FM does not affect the TE computations.

Multicenter study of pars plana vitrectomy for optic disc pit maculopathy: MACPIT study.

PurposeTo evaluate surgical intervention with pars plana vitrectomy (PPV) for correction of optic disc pit maculopathy (ODP-M).Patients and methodsRetrospective chart review from 13 centres of 51 eyes of 50 patients with ODP-M who underwent PPV between 2002-2014. Anatomic and final best-corrected visual acuity (BCVA) outcomes were evaluated for all cases with different adjuvant techniques.ResultsThere were 23 males and 27 females with median age 25.5 (6-68) years. Preoperative median foveal thickness was 694.5 (331-1384) µm and improved to 252.5 (153-1405) µm. Median BCVA improved from 20/200 (20/20000 to 20/40) to 20/40 (20/2000 to 20/20) with 20/40 or better in 31 eyes. Complete retinal reattachment was achieved in 44 eyes (86.3%) at 7.1 (5.9) months. The good surgical outcomes were achieved in different adjuvant groups. Median follow-up was 24 (6 to 120) months.ConclusionsThese results confirm the long-term effectiveness of PPV for ODP-M. Prospective studies are needed to determine the effectiveness of any adjuvant technique in improving the success of PPV for ODP-M.

Time of Flight-Secondary Ion Mass Spectrometry on isolated extracellular fractions and intact biofilms of three species of benthic diatoms.

Time of Flight-Secondary Ion Mass Spectrometry (ToF-SIMS) was used to study compositional characteristics of Extracellular Polymeric Substances (EPS) and compared these to characteristics of the EPS-matrix of intact diatom biofilms. Three benthic diatoms species were investigated, Cylindrotheca closterium, Navicula mutica and Nitzschia cf. brevissima. Comparison of the ToF-SIMS spectra of sequentially extracted EPS-fractions by cluster analysis and multidimensional scaling analysis (MDS) indicated that soluble and bound EPS were not distinguishable based on their ion spectra. On the contrary the water insoluble bicarbonate soluble (WIBS)-EPS-fraction formed a distinct cluster showing that this material was compositionally different from the other EPS-fractions. Ion spectra of the EPS-fractions were dissimilar to results obtained from intact biofilms. This suggested that during the extraction procedure, the structure of the EPS irreversibly changed, which alters the fragmentation patterns of the extracellular surface layer. Furthermore, from the examination of the positive ion spectra it was shown that the overall composition of EPS in the intact biofilms was different between diatom species. In spite of these differences, several common peak patterns were shared between different species. This suggests the presence of common structural components in the EPS of these diatoms that may play a role in building the surface EPS-layer.

Comparison of topical and subconjunctival anesthesia in intravitreal injection administrations.

PURPOSE: To compare the effectiveness of topical and subconjunctival anesthesia in intravitreal injection administrations. METHODS: Twenty-eight patients from a university clinic with bilateral diabetic macular edema were prospectively randomized to receive intravitreal injection of 4 mg triamcinolone under topical anesthesia for one eye and subconjunctival anesthesia for the other eye by using lidocaine 4%. Patients were asked to grade the pain they experienced during administration of both anesthesia and intravitreal injection by using a 4-point pain scale: from 0=no pain to 3=severe pain. Complications that developed during both procedures were recorded. RESULTS: The mean pain score experienced during subconjunctival injections was 0.78+/-0.62, whereas no anesthesia-related pain was reported in the topical group. The mean pain score experienced during intravitreal injection was 1.64+/-0.67 in the topical and 0.85+/-0.52 in the subconjunctival group (p<0.001). The mean total pain scores of both procedures were 0.82+/-0.34 in the topical and 0.82+/-0.51 in the subconjunctival group (p>0.05). Nine eyes (32%) developed subconjunctival haemorrhage after subconjunctival injection, whereas no anesthesia-related complication developed in the topical group. Subconjunctival haemorrhage was also observed in 5 eyes (18%) in the topical group and in 11 eyes (40%) in the subconjunctival group (p>0.05) after intravitreal injection. CONCLUSIONS: Although subconjunctival anesthesia provides better pain control during intravitreal injections, its application is more painful and leads to subconjunctival haemorrhage. Moreover, the mean total pain scores are similar in both methods. Therefore, topical anesthesia may be more suitable for daily practice.

Study of the interaction of sulphate-reducing bacteria exopolymers with iron using X-ray photoelectron spectroscopy and time-of-flight secondary ionisation mass spectrometry.

Time-of-flight secondary ionisation mass spectrometry and X-ray photoelectron spectroscopy were employed to determine the interaction of crude extracellular polymeric substances recovered from static batch cultures of two isolates of marine sulphate-reducing bacteria of the genus Desulfovibrio, grown in the presence of and without mild steel surfaces, with Fe ions released from steel. The results demonstrated that exopolymers synthesised by different strains of sulphate-reducers varied in their ability to bind iron originating from steel. Based on the X-ray photoelectron spectroscopy analysis it is proposed that Fe released from steel was associated with bacterial exopolymers such as Fe(III) ion. The application of surface science techniques to study exopolymer/metal interaction allowed quantitative evaluation of Fe binding using small sample size.

Prediction of visual outcome after retinal detachment surgery using the Lotmar visometer.

AIM: To evaluate whether an achromatic interferometer, the Lotmar visometer, is useful in predicting postoperative visual outcome in patients with primary rhegmatogenous retinal detachment (RD) involving the macula. METHODS: This prospective study included 40 eyes of 40 non-consecutive patients with macula-off RD. The eyes were phakic or pseudophakic, had a clear optical media, and had a measurable potential vision on preoperative visometric examination. Preoperative variables included Snellen visual acuity, duration of macular detachment, extent of RD, and visometric potential acuity. Reattachment surgery consisted of radial scleral buckling in 33 patients, circumferential scleral buckling and encircling in seven patients, and subretinal fluid drainage in 10 patients. Retinal breaks were treated with cryotherapy or laser photocoagulation. Patients were followed up for at least 6 months after uncomplicated surgery. Best corrected visual acuity measured at any time during follow up was correlated with the preoperative variables. RESULTS: Preoperative visual acuity was less than 20/200 in 37 (93%) of 40 patients. Potential visual acuity of 20/200 or better was measured using the Lotmar visometer in 37 patients (93%). Postoperative visual acuity was correlated significantly with duration of macular detachment (r=0.55; p<0.001), and extent of RD approached statistical significance (r=0.31; p=0.05). There was a higher correlation between postoperative visual acuity and the visometric measurements (r=0.61; p<0.001). CONCLUSIONS: The Lotmar visometer may be a valuable method to estimate visual outcome after uncomplicated scleral buckling surgery in patients with RD involving the macula.

Effect of posterior subtenon injection of 40 mg of triamcinolone acetonide on glycemic control and serum cortisol and adrenocorticotropic hormone in diabetic patients.

OBJECTIVE: To evaluate the influence of posterior subtenon injection of 40 mg of triamcinolone acetonide (TA) on blood glucose, cortisol and adrenocorticotrophic hormone (ACTH) in patients with clinically significant diabetic macular oedema. PATIENTS AND METHODS: This prospective clinical study included 33 type 2 diabetic patients assigned to receive subtenon injection of 40 mg of TA (study group: 20 patients, 9 women and 11 men, mean age 60.8 ± 10.1 years) or subtenon injection of 1 ml of saline solution (control group: 13 patients, 7 women and 6 men, mean age 57.9 ± 7.5 years) as an adjunct to focal/grid laser therapy. Pre-injection laboratory tests consisted of fasting blood glucose (FBG), glicolised hemoglobin (HbA1c), fructosamine, ACTH and cortisol. Post-injection measurements were performed in a following schedule: FBG in day 1; FBG, ACTH and cortisol at week 1; FBG, fructosamine, ACTH and cortisol at month 1, 2 and 3. HbA1c was also measured at 3 months. The mean ± SD values of groups at each visit were compared. The time-related changes in the parameters in each group were also analyzed using SPSS (Statistical Package for Social Sciences) for Windows 15.0 software. RESULTS: Pre-injection FBG, HbA1c, fructosamine, ACTH and cortisol were similar in both groups (p > 0.05 for all). Pre-injection and final HbA1c values were similar in the study (8.6% ± 1.9 and 8.7% ± 1.8, respectively) and control groups (8.6% ± 1.7 and 8.5% ± 1.8, respectively) (p > 0.05 for all). None of the patients had a decrease in plasma cortisol that decreased below normal values at either time point. There was no statistically significant difference between groups and between each visit in groups according to FBG levels, blood fructosamine, ACTH and cortisol levels (p > 0.05 for all). No adverse event was observed. CONCLUSIONS: Subtenon injection of 40 mg of TA does not increase blood sugar levels significantly, and it does not suppress blood cortisol or ACTH levels at 1 week or later in patients with diabetes mellitus. Subtenon injection of 40 mg TA seems to be safe in respect to elevation of blood sugar levels or systemic corticosteroid pathways.

Long-term outcomes of pars plana vitrectomy without internal limiting membrane peeling for optic disc pit maculopathy.

PURPOSE: To evaluate the results of surgical treatment of maculopathy secondary to congenital optic pit anomaly with pars plana vitrectomy (PPV), endolaser to the temporal edge of the optic disc and C3F8 tamponade without internal limiting membrane (ILM) peeling. PATIENTS AND METHODS: Thirteen eyes of 12 patients with serous macular detachment and/or macular retinoschisis secondary to congenital optic disc pit (ODP) were included in the study. All eyes underwent PPV, posterior hyaloid removal, endolaser photocoagulation on the temporal margin of the optic disc and 12% C3F8 gas tamponade. Anatomic success and functional outcome determined retrospectively by optical coherence tomography and measurement of best corrected visual acuity (BCVA), respectively were the main outcome parameters. RESULTS: Two lines or more improvement in BCVA was obtained in 11 eyes and 6 of these eyes had 20/40 or better BCVA at the final visit. Subretinal or intraretinal fluid was completely resorbed postoperatively in 12 eyes but a little intraretinal fluid persisted in one eye at the 16-month follow-up. Better visual improvement was observed in patients treated by earlier surgical intervention. CONCLUSION: PPV, C3F8 gas tamponade and endolaser to the optic disc margin without ILM peeling may yield favourable results in the treatment of ODP maculopathy.

Long-term results of excision of plaque-like foveal hard exudates in patients with chronic diabetic macular oedema.

OBJECTIVE: To analyse the long-term results of surgical removal of plaque-like diabetic foveal hard exudates. METHODS: In this retrospective, interventional, non-randomized, controlled study, vitrectomy and excision of submacular hard exudates was performed on 11 eyes of 11 patients with plaque-like hard exudates. The mean preoperative LogMAR best corrected visual acuity (BCVA) and exudate diameter were 1.35+/-0.3 and 1.19 disks (range, 0.5-1.8), respectively. In the control group, which consisted of 10 eyes of 7 patients who refused the surgery, baseline mean BCVA and exudate diameter were 1.06+/-0.2 and 1.2 disks (range, 0.7-2.0), respectively. Main outcome measures included BCVA, fundus photography, and surgical complications. RESULTS: The mean follow-up was 39.1+/-3.2 months for the study group and 32.5+/-3.6 months for the control group. In the study group, BCVA improved in 8 (73%) eyes at the final examination. The mean final BCVA was 1.08+/-0.4 (P=0.021). Macular oedema and exudates resolved completely in all eyes. In the control group, final LogMAR visual acuity declined to 1.53+/-0.1 (P=0.005). Macular pigment epithelium atrophy or scar formation was observed in 7 (64%) eyes in the study group and in all eyes in the control group. CONCLUSION: Surgical excision of plaque-like foveal hard exudates resulted in better anatomical and functional outcome when compared to observation alone.

Evaluation of arteriovenous crossing sheathotomy for decompression of branch retinal vein occlusion.

PURPOSE: To report the effects of arteriovenous adventitial sheathotomy on anatomical and functional improvements in patients with macular oedema due to branch retinal vein occlusion (BRVO). METHODS: Pars plana vitrectomy and arteriovenous sheathotomy was performed on 11 patients with BRVO who had vision loss due to macular oedema. Ten patients with macular oedema due to BRVO and who have been treated with grid laser photocoagulation were included in the control group. The measurement of visual acuity with ETDRS chart was taken preoperatively and at 1, 3, 6, and 9 months follow-up in the study group and at 1, 3, 6, and 9 months after grid laser in the control group. RESULTS: The mean preoperative logMAR visual acuity was 0.84+/-0.3 in the surgical group and 1.06+/-0.4 in the control group. The postoperative mean logMAR visual acuity was 0.41+/-0.2, 0.40+/-0.2, 0.40+/-0.3, and 0.36+/-0.3 at 1, 3, 6, and 9 months follow-up, respectively. In the control group the postlaser mean logMAR visual acuity was 0.92+/-0.3, 0.87+/-0.4, 0.85+/-0.3, and 0.82+/-0.3 at 1, 3, 6, and 9 months follow-up, respectively. The improvements of visual acuity in both groups were statistically significant when compared to pretreatment (P=0.003 and P=0.007 at 9 months in the study and control group, respectively). CONCLUSION: Arteriovenous sheathotomy for decompression of BRVO in patients who have vision loss due to macular oedema was safe and effective for anatomical and functional improvement and resulted in significantly better visual outcomes than a matched control group of laser-treated eyes.

Preservation of bone collagen from the late Cretaceous period studied by immunological techniques and atomic force microscopy.

Late Cretaceous avian bone tissues from Argentina demonstrate exceptional preservation. Skeletal elements are preserved in partial articulation and suspended in three dimensions in a medium-grained sandstone matrix, indicating unusual perimortem taphonomic conditions. Preservation extends to the microstructural and molecular levels. Bone tissues respond to collagenase digestion and histochemical stains. In situ immunohistochemistry localizes binding sites for avian collagen antibodies in fossil tissues. Immunohistochemical studies do not, however, guarantee the preservation of molecular integrity. A protein may retain sufficient antigenicity for antibody binding even though degradation may render it incapable of original function. Therefore, we have applied atomic force microscopy to address the integrity and functionality of retained organic structures. Collagen pull-off measurements not only support immunochemical evidence for collagen preservation for antibody recognition but also imply preservation of the whole molecular integrity. No appreciable differences in collagen pull-off properties were measured between fossil and extant bone samples under physiological conditions.

Cataract surgery and transpupillary silicone oil removal through a single scleral tunnel incision under topical anesthesia; sutureless surgery.

The author evaluated the results of combined cataract extraction and transpupillary silicone oil removal through a single scleral tunnel incision, in eyes that had undergone pars plana vitrectomy with silicone oil tamponade. Twenty-four of the 46 eyes were operated on under topical anesthesia with Blumenthal mode mini-nucleus manual extracapsular cataract extraction technique (mini-nuc ECCE), and silicone oil was removed passively through planned posterior capsulorhexis via the scleral tunnel, followed by endocapsular intraocular lens (IOL) implantation. The operation was completed without any suturing. The remaining 22 eyes were similarly operated on with the same cataract extraction technique, but in these cases silicone oil was classically aspirated actively through pars plana sclerotomies. Results were evaluated by visual acuity measurement, duration of operation, and complications. The transpupillary silicone oil removal group had significantly less vitreous hemorrhage (0- 31.8%) and posterior capsule opacification (0-36.4%). Also, the mean duration of the operation was significantly shorter in this group. There was no significant difference between the two groups with regard to postoperative recurrence of retinal detachment (12.5-18.1%) and visual acuity outcome. The combination of mini-nuc ECCE with transpupillary silicone oil removal compares favorably with the combination of silicone oil aspiration through pars plana sclerotomies. This combined technique allows the surgeon to perform the operation under topical anesthesia and no sutures are required. The intervention period is shorter and no posterior capsule opacification or vitreous hemorrhage develops.

[Treatment of central serous choroidopathy with the beta receptor blocker metoprolol (preliminary results)]. / Die Behandlung der zentralen serösen Choroidopathie mit dem Betarezeptorenblocker Metoprolol (Vorläufige Ergebnisse).

Numerous theories have been proposed to explain the origin of central serous choroidopathy (CSC). However, it has been shown recently that there is a close relationship between CSC and type A-behaviour pattern (TABP) which is characterized by high adrenergic activity in the body. It is interesting to note that one of our patients who had chronic central serous choroidopathy, and metoprolol treatment for hypertension during one year, developed a recurrence of CSC three weeks after cessation of metoprolol treatment. This was one of the reasons to start this treatment modality for CSC. In this study, we present 6 cases of CSC in which the diagnosis was established by ophthalmoscopy and fluorescein angiography. In these patients, we proposed to analyse the relationship between CSC and a high adrenergic activity by the use of a selective beta-blocker (metoprolol; 50 mg tablets, twice daily). In two of the six cases, laser photocoagulation was also performed prior to commencement of the metoprolol treatment. Visual acuity improved in two patients, stayed at 1.0 in three patients and stabilized on the pretreatment level (0.8) in one patient (case-5). However, the symptoms (metamorphopsia and micropsia) and the signs (serous retinal detachment and angiographic hyperfluorescence) decreased or disappeared in all patients after treatment. Also visual complaints in all patients improved subjectively. No recurrences were noted during the metoprolol treatment in any of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of Pseudomonas NCIMB 2021 biofilm on AISI 316 stainless steel.

A bioreactor system operating in a continuous mode was designed to generate biofilms on polished and as-received surfaces of AISI 316 stainless steel coupons exposed for 36 d to a pure culture of marine Pseudomonas NCIMB 2021. Scanning electron microscopy (SEM) and atomic force microscopy were employed to determine the degree of surface colonisation and to examine corrosion damage of the steel. X-ray photoelectron spectroscopy analysis was carried out to characterise the chemistry of the passive layers on polished steel stored for a period of time, freshly re-polished coupons, and as-received steel. The effect of biofilms on the composition of layers formed on the steel specimens was evaluated. SEM revealed that the surfaces of polished and stored steel appeared to accumulate more biofilm compared to as-received specimens. Micropitting of steel occurred underneath the biofilm, regardless of surface finish. The concentration of elements in the passive layers differed significantly between freshly re-polished and as-received or polished and stored coupons. In the presence of Pseudomonas NCIMB 2021 biofilm, the composition of the passive layer on the as-received steel surface was considerably altered compared to unexposed steel or steel exposed to abiotic medium.

Cs(+) Speciation on Soil Particles by TOF-SIMS Imaging.

Soil particles exposed to CsI solutions were analyzed by imaging time-of-flight secondary ion mass spectrometry and also by scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). The results showed that Cs(+) could be detected and imaged on the surface of the soil particles readily at concentrations down to 160 ppm, which corresponds to 0.04 monolayer. Imaging revealed that most of the soil surface consisted of aluminosilicate material. However, some of the surface was more quartzic in composition, primarily SiO(2) with little Al. It was observed that adsorbed Cs(+) was associated with the presence of Al on the surface of the soil particles. In contrast, in high SiO(2) areas of the soil particle where little Al was observed, little adsorbed Cs(+) was observed on the surface of the soil particle. Using EDS, Cs(+) was observed only in the most concentrated Cs(+)-soil system, and Cs(+) was clearly correlated with the presence of Al and I. These results are interpreted in terms of multiple layers of CsI forming over areas of the soil surface that contain substantial Al. These observations are consistent with the hypothesis that the insertion of Al into the SiO(2) lattice results in the formation of anionic sites, which are then capable of binding cations.

Beta-keratin specific immunological reactivity in feather-like structures of the cretaceous alvarezsaurid, Shuvuuia deserti.

We report small fibrous structures associated with a new specimen of Shuvuuia deserti, which we hypothesize are remnants of feather-like epidermal appendages. Multiple analyses suggest that these structures are epidermally derived and contain epitopes consistent with beta-keratin, a protein expressed only in extant "reptiles" and birds. Morphological, microscopic, mass spectrometric, and immunohistochemical studies are consistent with the interpretation that these structures are related to feathers. These data suggest that proteinaceous components may survive across geological time and support the view that alvarezsaurids (Shuvuuia and its allies) are either a lineage of birds or are a lineage phylogenetically close to them. J. Exp. Zool. (Mol. Dev. Evol.) 285:146-157, 1999.

Characterization of interlayer Cs+ in clay samples using secondary ion mass spectrometry with laser sample modification.

Ultraviolet laser irradiation was used to greatly enhance the secondary ion mass spectrometry (SIMS) detection of Cs(+) adsorbed to soil consisting of clay and quartz. Imaging SIMS showed that the enhancement of the Cs(+) signal was spatially heterogeneous: the intensity of the Cs(+) peak was increased by factors up to 100 for some particles but not at all for others. Analysis of standard clay samples exposed to Cs(+) showed a variable response to laser irradiation depending on the type of clay analyzed. The Cs(+) abundance was significantly enhanced when Cs(+)-exposed montmorillonite was irradiated and then analyzed using SIMS, which contrasted with the behavior of Cs(+)-exposed kaolinite, which displayed no Cs(+) enhancement. Exposed illitic clays displayed modest enhancement of Cs(+) upon laser irradiation, intermediate between that of kaolinite and montmorillonite. The results for Cs(+) were rationalized in terms of adsorption to interlayer sites within the montmorillonite, which is an expandable phyllosilicate. In these locations, Cs(+) was not initially detectable using SIMS. Upon irradiation, Cs(+) was thermally redistributed, which enabled detection using SIMS. Since neither the illite nor the kaolinite is an expandable clay, adsorption to inner-layer sites does not occur, and either modest or no laser enhancement of the Cs(+) signal is observed. Laser irradiation also produced unexpected enhancement of Ti(+) from illite and kaolinite clays that contained small quantities of Ti, which indicates the presence of microscopic titanium oxide phases in the clay materials.