Trocar opening: silicone oil removal with phacoemulsification and intraocular lens implantation

AIM: To evaluate the efficacy and safety of a modified technique [trocar opening(TO)] for silicone oil removal(SOR) in combination with phacoemulsification and intraocular lens(IOL) implantation.METHODS: A total of 60 eyes of 60 patients with cataract and silicone oil-filled eyes were enrolled in this study. The patients were divided into two groups: the patients in the control group underwent 23-gauge pars plana active SOR surgery with phacoemulsification and IOL implantation, while the patients in the TO group underwent TO methods during surgery. Best corrected visual acuity(BCVA), surgery time, intraocular pressure, and operative complications were observed 6 mo after surgery.RESULTS: There was no significant difference between the two groups in terms of age, gender, preoperative, intraocular pressure, or time of silicone oil stay. Prior to surgery, the mean BCVA for the control and TO groups was 1.34±0.44 and 1.36±0.42. At 6 mo following surgery, the mean BCVA improved to 0.74±0.36 and 0.77±0.32, respectively(P<0.001). There was no significant difference between the two groups. The mean SOR time was 6.9±2.3 min and 4.8±1.2 min in the control and TO groups(P=0.008). The total operation time was 28.2±8.5 min and 24.6±6.4 min, respectively(P=0.035). Posterior capsule rupture occurred in four eyes of control and none of TO group(P<0.01). Late recurrent retinal detachment occurred in one eye in the control group(2 mo after surgery) and in one eye in the TO group(4 mo after surgery). CONCLUSION: TO is a simple, effective, time-saving, and safe method for SOR combined with phacoemulsification and IOL implantation.

Complicated calcified alloplastic implants in the nasal dorsum:A clinical analysis

BACKGROUND In rhinoplasty,calcification around silicone implants is frequently observed in the tip dorsum(TD)area.Additionally,based on a review of various literature,it is presumed that calcification in silicone implants occurs due to both inflammatory chemical reactions and physical friction against the tissue.The calcification of nasal silicone implants not only results in the functional loss of the implants,but also leads to material deformation.However,there is a lack of research on calcification of nasal silicone implants in the current literature.AIM To elucidate various clinical characteristics of calcification around nasal silicone implants,using histological and radiological analysis.METHODS This study analyzed data from 16 patients of calcified nasal implants,who underwent revision rhinoplasty for various reasons after undergoing augmentation rhinoplasty with silicone implants.The collected data included information on implant duration,implant types,location of calcification,presence of inflammatory reactions,and computed tomography(CT)scans.RESULTS The most common location of calcification,as visually analyzed,was in the TD area,accounting for 56%.Additionally,the analysis of CT scans revealed a trend of increasing Hounsfield Unit values for calcification with the duration of implantation,although this trend was not statistically significant(P=0.139).CONCLUSION Our study shows that reducing the frequency of calcification may be achievable by using softer silicone implants and by minimizing the damage to perioperative tissues.

Surgical Treatment of Penile Deformity Due to Curvature Using a Subcutaneous Soft Silicone Implant: Case Report

Introduction: Congenital and acquired penile curvature has a negative impact on penile aesthetics, sexual capabilities, and male psychology. Surgical procedures yield satisfactory correction of curvature, but are usually associated with penile shortening and palpable suture material and nodules under the skin, resulting in patient dissatisfaction. Aims: To present a novel technique using a subcutaneous soft silicone implant for surgical treatment of penile soft tissue deformities with curvature, with prevention of surgery-associated penile shortening and subcutaneous “bumps”, and with additional gains in overall penile length and girth. Method: 3 patients who complained about congenital, post-traumatic, and post-penile surgery associated penile curvature, with concerns about their penile aesthetics and associated negative psychosocial effects, were treated with the insertion of a subcutaneous soft silicone penile implant. Results: During a follow up period of 2 - 12 months (mean: 6.7 ± 3.6 months) all three patients expressed objective and subjective satisfaction regarding the corrective results of the surgery. Penile length and girth measurements during follow-up showed a mean increase in length of 4.3 cm (±1.4 cm) and a mean increase in girth of 3.0 cm (±1.0 cm). Conclusion: The insertion of the subcutaneous soft silicone implant in addition to corporeal fibrotic tissue removal in patients with congenital or acquired penile curvature is an effective option that provides the patient with aesthetic improvements by correcting penile deviation, preventing post-surgical subcutaneous nodule formation that results from the technique and suture material used, and adding penile length and girth. Further prospective studies are required to validate our initial experience.

Repeated Hemorrhage after Repair of Orbital Floor Fracture with a Silicone Implant

A 16-year-old girl was accidentally kicked in her right eye by her cheerleading teammate in an exercise. Upward gaze ability of her right eye was severely impaired and computed tomography (CT) showed a trapdoor fracture of the right orbital floor. After surgical exploration, a silicone implant was inserted. No bleeding was confirmed at this time. The next day, CT detected a hematoma on the right orbital floor. The hematoma was drained and meticulous cautery was used to control any potential bleeding. The same silicone implant was re-inserted. Irrespective of attempts to avoid hemorrhage, this occurred twice after the respective evacuations. During a fourth operation, we removed the silicone implant simultaneously with hematoma evacuation. No hematoma has occurred since, and the patient’s ocular movement has dramatically improved to a normal binocular single vision field. When repeated hemorrhages occur after an orbital floor fracture repair with insertion of a silicone implant, removal of the implant is an effective strategy to resolve the hemorrhage.

An Impact of Different Silicone Breast Implants on the Bacterial Attachment and Growth

Bacterial biofilms have been implicated with breast implant complications including capsular contracture, double-capsule formation, and breast implant-associated anaplastic large cell lymphoma. However, the relationship between implant surface texture and microbial biofilm formation is insufficiently evaluated. In the present study, we examined the antimicrobial activities of different types of silicone breast implant. The growth of bacterial including Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa was compared using implants with various surface textures, including Hans Smooth, Hans SmoothFine, Allergan Smooth, Eurosilicone Smooth, Eurosilicone Texture, Sebbin Smooth, Sebbin Micro, Sebbin Texture, and Motiva Smooth. Microbial investigation revealed the increased growth of S. aureus on breast implants after 48 h, except Eurosilicone Smooth, Eurosilicone Texture, Hans SmoothFine and Sebbin Smooth material. At 48 hours, there was no major difference between the S. aureus attachment on smooth and textured implants. The results of S. epidermis attachment on the implant after 48 h showed that their growth decreased on surfaces of Motiva Smooth, Sebbin Smooth, and Eurosilicone Smooth. These results indicated that S. epidermis was unable to survive on these breast implants. Eventually, P. aeruginosa count had showed decrease of bacterial count after 48 hours compared to 24 hours in most of the implants except for Eurosilicone Texture, Sebbin Smooth and Sebbin Micro, where the count of P. aeruginosa slightly increased. This indicated that P. aeruginosa was unable to exist on the smooth surfaces. Our results show that the in vitro assay revealed no significant difference between smooth and textured surfaces and showed variable interactions and needed further molecular analysis to assess their adherence nature.

Granulomatous Inflammatory Reaction in Breast Silicone Implants

Introduction： breast implants have been used to correct the size and the form of a breast in post-mastectomy breast reconstruction, for correcting congenital defects and deformities or for purely aesthetic breast augmentation. Silicone breast implants were introduced in the 1960s. They are non without complications, like rupture is or silicone gel bleeding. Materials and methods： the authors present the case of 50 patients, aged 45-55, who presented to our attention after 15 （＋ 5） years of the application of silicone breast implant for the appearance of lumps under the skin in the armpit area. These were palpable, painless except on palpation. The patients reported burning in the affected area, but no other symptoms. Results： considering the presence in each of them of silicone implants, and assuming a possible allergic basis, the authors performed a patch test series S1DAPA produced by F.I.R.M.A Spa, Firenze, ultrasound and MR and blood tests. In all patients the allergy test （patch test） were negative, ultrasound and MR have shown that no hearing was damaged or broken. Blood test showed no abnormalities. Discussion： comparing the authors＇ study with other similar works in the literature, they noted that the reported cases of hypersensitivity type 4 silicone prosthesis was not only initially accompanied by specific symptoms such as urticaria and blistering, but mostly it was found to be a net positive patch test. The absence of urticaria, the low values of lgE and total negativity of patch test confirmed the purely inflammatory nature of the lesions in our patients.

Thermal annealing induced photocarrier radiometry enhancement for ion implanted silicon wafers

An experimental study on the photocarrier radiometry signals of As^＋ ion implanted silicon wafers before and after rapid thermal annealing is performed. The dependences of photocarrier radiometry amplitude on ion implantation dose （1×10^11-1×10^16/cm^2）, implantation energy （20-140 keV） and subsequent isochronical annealing temperature （500- 1100℃ are investigated. The results show that photocarrier radiometry signals are greatly enhanced for implanted samples annealed at high temperature, especially for those with a high implantation dose. The reduced surface recombination rate resulting from a high built-in electric field generated by annealing-activated impurities in the pn junction is believed to be responsible for the photocarrier radiometry signal enhancement. Photocarrier radiometry is contactless and can therefore be used as an effective in-line tool for the thermal annealing process monitoring of the ion-implanted wafers in semiconductor industries.

Realization of conformal doping on multicrystalline silicon solar cells and black silicon solar cells by plasma immersion ion implantation

Emitted multi-crystalline silicon and black silicon solar cells are conformal doped by ion implantation using the plasma immersion ion implantation （PⅢ） technique. The non-uniformity of emitter doping is lower than 5 %. The secondary ion mass spectrometer profile indicates that the PⅢ technique obtained 100-rim shallow emitter and the emitter depth could be impelled by furnace annealing to 220 nm and 330 nm at 850 ℃ with one and two hours, respectively. Furnace annealing at 850 ℃ could effectively electrically activate the dopants in the silicon. The efficiency of the black silicon solar cell is 14.84% higher than that of the mc-silicon solar cell due to more incident light being absorbed.

Dopant Implantation into the Silicon Substrate with Non-Planar Surface

The influence of technological process parameters (aiming angle and implantation energy) on the distributions of dopant concentrations in a silicon substrate is investigated by computer modeling.

Study on the defect-related emissions in the light self-ion-implanted Si films by a silicon-on-insulator structure

This paper reports that the Si＋ self-ion-implantation are conducted on the silicon-on-insulator wafers with the 2SSi＋ doses of 7 ×1012, 1 × 1013, 4 × 1013, and 3× 1014 cm-2, respectively. After the suitable annealing, these samples are characterized by using the photoluminescence technique at different recorded temperatures. Plentiful emission peaks are observed in these implanted silicon-on-insulator samples, including the unwonted intense P~ band which exhibits a great potential in the optoelectronic application. These results indicate that severe transformation of the interstitial clusters can be manipulated by the implanting dose at suitable annealing temperatures. The high critical temperatures for the photoluminescence intensity growth of the two signatures are well discussed based on the thermal ionization model of free exciton.

Total dose radiation response of modified commercial silicon-on-insulator materials with nitrogen implanted buried oxide

Nitrogen ions of various doses are implanted into the buried oxide （BOX） of commercial silicon-on-insulator （SOI） materials, and subsequent annealings are carried out at various temperatures. The total dose radiation responses of the nitrogen-implanted SOI wafers are characterized by the high frequency capacitance-voltage （C-V） technique after irradi- ation using a Co-60 source. It is found that there exist relatively complex relationships between the radiation hardness of the nitrogen implanted BOX and the nitrogen implantation dose at different irradiation doses. The experimental results also suggest that a lower dose nitrogen implantation and a higher post-implantation annealing temperature are suitable for improving the radiation hardness of SOI wafer. Based on the measured C V data, secondary ion mass spectrometry （SIMS）, and Fourier transform infrared （FTIR） spectroscopy, the total dose responses of the nitrogen-implanted SOI wafers are discussed.

Photoluminescence evolution in self-ion-implanted and annealed silicon

Si^＋ ion-implanted silicon wafers are annealed at different temperatures from room temperature to 950℃ and then characterized by using the photoluminescence （PL） technique at different recorded temperatures （RETs）. Plentiful optical features are observed and identified clearly in these PL curves. The PL spectra of these samples annealed in different temperature ranges are correspondingly dominated by different emission peaks. Several characteristic features, such as an R line, S bands, a W line, the phonon-assistant WTA and SiTO peaks, can be detected in the PL spectra of samples annealed at different temperatures. For the samples annealed at 800℃, emission peaks from the dislocations bounded at the deep energy levels of the forbidden band, such as D1 and D2 bands, can be observed at a temperature as high as 280 K. These data strongly indicate that a severe transformation of defect structures could be manipulated by the annealing and recorded temperatures. The deactivation energies of the main optical features are extracted from the PL data at different temperatures.

Improvement of total-dose irradiation hardness of silicon-on-insulator materials by modifying the buried oxide layer with ion implantation

The hardening of the buried oxide （BOX） layer of separation by implanted oxygen （SIMOX） silicon-on-insulator （SOI） wafers against total-dose irradiation was investigated by implanting ions into the BOX layers. The tolerance to total-dose irradiation of the BOX layers was characterized by the comparison of the transfer characteristics of SOI NMOS transistors before and after irradiation to a total dose of 2.7 Mrad（SiO2）. The experimental results show that the implantation of silicon ions into the BOX layer can improve the tolerance of the BOX layers to total-dose irradiation. The investigation of the mechanism of the improvement suggests that the deep electron traps introduced by silicon implantation play an important role in the remarkable improvement in radiation hardness of SIMOX SOI wafers.

Influence of nitrogen implantation into the buried oxide on the radiation hardness of silicon-on-insulator wafers

In order to improve the total-dose radiation hardness of the buried oxide of separation by implanted oxygen silicon- on-insulator wafers, nitrogen ions were implanted into the buried oxide with a dose of 1016 cm-2, and subsequent annealing was performed at 1100 ℃. The effect of annealing time on the radiation hardness of the nitrogen implanted wafers has been studied by the high frequency capacitance-voltage technique. The results suggest that the improvement of the radiation hardness of the wafers can be achieved through a shorter time annealing after nitrogen implantation. The nitrogen-implanted sample with the shortest annealing time 0.5 h shows the highest tolerance to total-dose radiation. In particular, for the 1.0 and 1.5 h annealing samples, both total dose responses were unusual. After 300-krad（Si） irradiation, both the shifts of capacitance-voltage curve reached a maximum, respectively, and then decreased with increasing total dose. In addition, the wafers were analysed by the Fourier transform infrared spectroscopy technique, and some useful results have been obtained.

Combined frequency- and time-domain photocarrier radiometry characterization of ion-implanted and thermally annealed silicon wafers

A combined frequency-swept and quasi-time-domain photocarrier radiometry （PCR） technique was developed to characterize thermally annealed silicon wafers with B＋, P＋, and As＋ ion implantation at doses ranging from 1 ×1011 cm-2 to 1 ×1016 cm-2. The implantation dose dependence of the PCR amplitude, the frequency dependencies of the PCR amplitude and phase, as well as the quasi-time-domain PCR waveforms were simultaneously employed to analyze all the ion-implanted silicon samples. The dependence of the effective lifetime on the implantation dose has been investigated and shown to be related to the trap density and the lifetime extracted from the transient PCR signals.

Investigation of the lateral spread of erbium ions implanted in silicon crystal

The erbium ions at energy of 400 keV and dose of 5× 10^15 ions/cm^2 were implanted into silicon single crystals at room temperature at the angles of 0°,45° and 60°. The lateral spread of 400 keV erbium ions implanted in silicon sample was measured by the Rutherford backscattering technique. The results show that the measured values were in good agreement with those obtained from the prediction of TRIM＇98 （Transport of Ions in Matter） and SRIM2006 （Stopping and Range of Ions in Matter） codes.

Study of the lateral distribution of neodymium ions implanted in silicon

Due to the need to reduce electronic device sizes, it is very important to consider the depth and lateral distribution of ions implanted into a crystalline target. This paper reports that Nd ions with energies of 200 keV to 500 keV and dose of 5× 10^15 ions/cm2 are implanted into Si single crystals at room temperature under the angles of 0°, 30°, and 45°, respectively. The lateral spreads of 200 keV-500 keV Nd ions implanted in Si sample are measured by Rutherford backscattering technique. The results show that the measured values are in good agreement with those obtained from the prediction of SRIM2010 codes.

Boron implanted emitter for n-type silicon solar cell

The effects of ion doses on the properties of boron implanted Si for n-type solar cell application were investigated with doses ranging from 5×10^14cm^-2 to 2×10^15cm^-2 and a subsequent two-step annealing process in a tube furnace.With the help of the TCAD process simulation tool, knowledge on diffusion kinetics of dopants and damage evolution was obtained by fitting SIMS measured boron profiles. Due to insufficient elimination of the residual damage, the implanted emitter was found to have a higher saturation current density（J0e） and a poorer crystallographic quality. Consistent with this observation, V oc, J sc, and the efficiency of the all-implanted p^＋–n–n^＋solar cells followed a decreasing trend with an increase of the implantation dose. The obtained maximum efficiency was 19.59% at a low dose of 5×10^14cm^-2. The main efficiency loss under high doses came not only from increased recombination of carriers in the space charge region revealed by double-diode parameters of dark I–V curves, but also from the degraded minority carrier diffusion length in the emitter and base evidenced by IQE data. These experimental results indicated that clusters and dislocation loops had appeared at high implantation doses, which acted as effective recombination centers for photogenerated carriers.

Analytical model for capacitance-voltage characteristics of ion-implanted 4H silicon carbide Schottky barrier diodes

In order to undertake theory analysis in the application area of switching,frequency and power devices,an analytical model for capacitance-voltage (C-V) characteristics of ion-implanted 4H silicon carbide (SiC) Schottky barrier diodes (SBDs) was investigated.This model was established by considering the effects of incomplete ionization of nitrogen in 4H-SiC,the Poole-Frenkel on the ionization energy,and the ion-implanted nitrogen donor profiles.The simulation process is discussed in detail for two multiple nitrogen ion-implanted 4H-SiC SBDs (three and four fold ion-implantations) designed and fabricated in the experiments using this model at different activation rates.An agreement between the modeled C-V curves and the measured results for two ion-implanted 4H-SiC SBDs fabricated is shown.This capacitance model has the potential to be used to simulate and design ion-implanted SiC devices concerned in the future.

Characteristics of Si^+/B^+ dual implanted silicon wafers

Thin p + layers with good electrical properties were fabricated by RTA (rapid thermal annealing) with post FA (furance annealing) of Si +/B + dual implanted silicon wafers. The electrical and structural characteristics of thin p + layers have been measured by FPP (four point probe), SRP (spreading resistance probe), RBS/channelling. Optimizing the implantation and annealing processes, especially using the thermal cycle of RTA followed by FA, shallow p +n junctions can be fabricated, which shows excellent I V characteristics with revers bias leakage current densities of 1.8?nA/cm 2 at -1.4?V.