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Yukihiko Suzuki, Toshio Tando, Kobu Adachi, Takashi Kudo, Mitsuru Nakazawa Department of Ophthalmology, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, JapanCorrespondence: Yukihiko Suzuki Tel +81-172-39-5095Fax +81-172-37-5735Email yukihiko@hirosaki-u.ac.jpIntroduction: We developed a new technique that uses two of the vitrectomy ports as intraocular lens (IOL) haptic fixation sites and compared that with a conventional T-fixation method.Methods: A total of 33 eyes were retrospectively divided into the port-fixation (n=21) and conventional (n=12) groups. For the port-fixation group, supranasal and inferotemporal trocars (25-gauge) were placed in the center of a T-shaped lamellar scleral incision 2 mm from the corneal limbus and a supratemporal trocar at 3.5 mm. Following a vitrectomy, along with lens or IOL extraction as needed, the infusion cannula was changed from an inferotemporal to supratemporal trocar. The first IOL haptic and trocar were then simultaneously withdrawn from the eye by grasping with vitreoretinal forceps, with the same performed for the second IOL haptic and trocar, after which the infusion cannula was removed. In the conventional group, 2 T-shaped scleral incisions and three trocars were separately placed.Results: Postoperatively, transient ocular hypotension and hypertension were observed in a few eyes in both groups. At 6 months after surgery, astigmatism was 1.71± 1.13 D in the port-fixation group and 2.21± 1.78 D in the conventional group (p=0.40, t-test).Conclusion: This new technique may be effective because of the lower number of scleral wounds.Keywords: intraocular lens, intrascleral fixation, cataract surgery, lens subluxation, vitrectomy

Yukihiko Suzuki, Kobu Adachi, Yoshihiro Jinnai, Kaori Suzuki, Mitsuru Nakazawa Department of Ophthalmology, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan Abstract: We developed intraocular lens (IOL) fixation procedure that only uses one suture during Zinn’s zonule dialysis portion of the combined surgery for IOL intracapsular fixation and unilateral loop suture for preserving the lens capsule. We treated 15 eyes in 15 patients which were confirmed to have almost 180° zonular dialysis during cataract surgery. After removing the lens, a scleral flap was created on the dialysis side. A straight needle for suturing was then inserted into the anterior chamber from the opposite side of the dialysis. The needle was used to attach the equatorial segment of the capsule on the dialysis side from the inside to the outside and then pull the suture thread under the scleral flap. After the thread was bound to a preceding loop of IOL, the IOL was inserted into the bag. Our procedure was found to be simple and less invasive, as our technique required no vitrectomy to be performed. Keywords: intraocular lens, zonular dialysis, IOL scleral suturing, cataract surgery

A 12-Channel (Ch) CMOS Preamplifier-Shaper-Discriminator ASIC designed for avalanche photodiode (APD) and gas counter readout has been fabricated on a 2.4 mm x 2.4 mm die area using ROHM 0.35-[micro]CMOS technology. This mixed signal ASIC consists of both analog and digital components and a window type discriminator is easily implemented through the use of a digital encoder to encode outputs from two comparators. The charge sensitive preamplifier is based on gain-boosted (regulated) cascode topology. The gain (voltage output to charge input) is 0.9 mV/fC and has been tested to have a low optimum Equivalent Noise Charge (ENC) of about 370 [e.sup.-] + 30 [e.sup.-]/pF rms at a shaping time of 0.5 [micro]s. The gain of the shaper is about 2.5 mV/fC and its peaking time can be varied from about 0.3 [micro]s to 0.8 [micro]s via an external pin. This chip is capable of sensing bipolar signals and is linear at least up to 320 fC for negative charge and 150 fC for positive charge. The average ENC of each channel has been calculated to be about 640 [e.sup.-] + 30 [e.sup.-]/pF. The power consumption of the chip is approximately 0.13 W. Index Terms--Application-specific integrated circuit (ASIC), avalanche photodiode (APD), complementary metal-oxide semiconductor (CMOS), gas detector.

In recent years, cryogenic microcalorimeters using their superconducting transition edge have been under development for possible application to the research for astronomical X-ray observations. To improve the energy resolution of superconducting transition edge sensors (TES), several correction methods have been developed. Among them, a clustering method based on digital signal processing has recently been proposed. In this paper, we applied the clustering method to Ir/Au bilayer TES. This method resulted in almost a 10% improvement in the energy resolution. Conversely, from the point of view of imaging X-ray spectroscopy, we applied the clustering method to pixellated Ir/Au-TES devices. We will thus show how a clustering method which sorts signals by their shapes is also useful for position identification.

In this paper we propose a new type of two-dimensional (2-D) multigrid-type microstrip gas chamber (M-MSGC) using multilayer technology. In order to reduce the number of readout lines without image distortion, we introduce a new encoding scheme, the global-local grouping (GLG) method. In this approach global and local signals are used to locate the coarse and fine position information, respectively. We have designed, fabricated, and tested the GLG M-MSGC plate with an active area of 10 x 10 [cm.sup.2]. The results confirmed that the principle of 2-D GLG M-MSGC is successful. Index Terms--Encoding method, gas detector, global-local grouping method, microstrip gas chamber (MSGC), position-sensitive detector.

A 10-channel (Ch) and a 16-Ch application specific integrated circuit (ASIC) preamplifier chip with telescopic-cascode topology and gain-boosted (regulated) cascode topology respectively has been designed for avalanche photodiode (APD) and microstrip gas chamber (MSGC) readouts. These highly integrated and reliable chips can be used for individual readouts from many channels to improve the spatial resolution and counting rate of such detectors over light sharing or charge division schemes. These chips were fabricated on a 2.4 x 2.4 mm die area using ROHM 0.35-[micro] CMOS technology. The chips were tested to have a low optimum equivalent noise charge (ENC) of about 880 [e.sup.-] a shaping time of 0.5 [micro]s. The voltage output to charge input gains of the 10-Ch and 16-Ch preamplifiers are 0.71/pf and 0.91/pf while the rise times (10%-90%) are 15 and 13 ns, respectively. The 16-Ch chip was used to readout a GSO-APD detector and an optimum energy resolution of 11.3% (511 Kev peak of Na-22) was obtained while the coincidence time resolution with two such detectors is about 12.5 ns. The energy resolution of the 5.9 keV peak from a Fe-55 source obtained with a 3 x 3 cm MSGC plate was about 20.5 %.

Characteristics of a SrBP[O.sub.5] : [Eu.sup.2+] material have been investigated as a neutron storage phosphor. The authors found that this phosphor shows photostimulated luminescence (PSL) by illumination with 635 nm laser light after neutron irradiation. The light with shorter wavelength than 635 nm seemed to be more efficient to produce PSL signal. The optimal concentration of Eu was 2% (mol %). The phosphor might be usable in a high gamma-ray field. The fading characteristics were similar to those of a commercially available neutron imaging plate. Using a disk-like sample, a collimated neutron beam image was clearly obtained by scanning focused laser light on it. The spatial resolution of 0.4 mm was obtained from the Edge Spread Function measurement. Index Terms--Gamma-ray sensitivity, neutron imaging plate, neutron sensitivity, SrBP[O.sub.5] : [Eu.sup.2+].

Research involving superconducting-transition-edge temperature sensors (TES) for calorimeters is described and discussed.