Frequency of Nd:YAG capsulotomy after implantation of PMMA and silicon intraocular lenses

From July 1, 1991, until January 1, 1993, a total of 7,720 patients (soldiers and civilians) with war wounds were treated at Dr. Josip Bencevi? General Hospital in Slavonski Brod, Croatia. Treatment was provided for 7,043 patients, whereas 677 individuals (8.8%) killed in action (KIA) were examined at the Forensic Department. There were 1,456 patients (18.9%) with head and neck wounds: 1,176 soldiers and 280 civilians. The mortality rate was significantly greater in patients with head and neck wounds (N = 271, 40.0%) than in those with injuries to the thorax (N = 163, 24.1%) and abdomen (N = 62, 9.2%; p < 0.01 for both). During treatment, 188 patients (2.4%) died of wounds (DOW). The DOW mortality was 5.2% (61 of 1,185), 4.0% (41 of 1,026), and 2.9% (25 of 867) for wounds of the head and neck, thorax, and abdomen, respectively. There was no significant difference in the mortality rate between head and neck and thorax wounds: however, the former exceeded the mortality rate recorded for abdominal wounds (p < 0.05). No significant differences were observed between soldiers and civilians with head and neck injuries either in the KIA (205 of 1,176, 17.4% vs. 66 of 280, 23.5%, respectively) or the DOW group (51 of 971, 5.3% vs. 10 of 214, 4.7%, respectively. According to the mechanism of head and neck wounding, there were 1,046 explosive (71.9%), 226 gunshot (15.5%), and 184 other (12.6%) wounds. Lethal outcome was significantly more common in gushot than in explosive wounds (79 of 226, 35% vs. 243 of 1,046, 23.2%; p < 0.01). The proportion of head and neck injuries did not differ significantly from literature reports on recent conventional wars. The site of wounding, i.e., at the battlefield or elsewhere, had no effect on the prognosis of wounds to the head and neck. Gunshot head and neck injuries showed a significantly higher mortality rate.     

Laser skin resurfacing with the Q-switched Nd:YAG laser

BACKGROUND: Recent studies have shown that char-free pulsed carbon dioxide lasers are useful in the treatment of rhytids. Other infrared lasers have also been observed to induce changes in the skin. OBJECTIVE: In this pilot study, we evaluated the rhytid resurfacing capability of the Q-switched neodymium:yttrium-aluminum-garden (QS Nd:YAG) laser at 1064 nm as compared with char-free carbon dioxide lasers at 10,600 nm. METHODS: Three lasers were used in the study: The QS Nd:YAG laser, the SilkTouch carbon dioxide laser, and the UltraPulse carbon dioxide laser. Eleven subjects were treated in either the periorbital or perioral region with the QS Nd:YAG laser on one side of the face, and both of the char-free pulsed carbon dioxide lasers on the other side. The subjects were evaluated at posttreatment days 7, 30, 60, and 90 for improvement of rhytids, healing, pigmentary changes, and erythema. RESULTS: All 11 patients treated with the char-free carbon dioxide lasers improved. Nine of 11 patients treated with the QS Nd:YAG laser were improved. Healing (complete reepithelialization) was noted to occur 3-6 days earlier in sites treated with the QS Nd:YAG than in sites treated with char-free carbon dioxide lasers. Pigmentary changes were not observed in any treatment site. Erythema was observed at 1 month after treatment in all areas treated with the char-free carbon dioxide lasers, but only three patients treated with the QS Nd:YAG exhibited erythema. These were the same three QS Nd:YAG-treated patients whose clinical improvement was comparable with that of the char-free carbon dioxide lasers. CONCLUSION: The Q-switched Nd:YAG laser may play a role in the treatment of rhytids.     

Nd:YAG laser treatment for premacular hemorrhage

The authors describe two cases of premacular hemorrhage secondary to retinal macroaneurysm, with significant loss of vision. A few low-energy bursts of ND:YAG laser were applied to perforate the anterior surface of the hemorrhage, subsequently draining the blood into the vitreous cavity. The blood gradually cleared from the vitreous, with restoration of good vision. Nd:YAG laser seems to be a safe and efficient method for treating premacular hemorrhage and should be considered as a therapeutic option.     

Incidence, causes, and neodymium:YAG laser treatment of pupillary capture

OBJECTIVE: To report the incidence of and factors associated with pupillary capture after cataract surgery and evaluate the outcomes of treatment with the neodymium:YAG (Nd:YAG) laser. SETTING: Unit of Ophthalmology, University of Edinburgh, and Royal Infirmary of Edinburgh Trust Hospital, Edinburgh, United Kingdom. METHODS: This prospective study comprised 792 consecutive patients having cataract extraction by one surgeon from 1989 to 1993. Outcome measures were incidence of pupillary capture associated with eye disease and treatment, surgical technique, and intraocular lens (IOL) placement and style; postoperative progress; and results of Nd:YAG treatment. RESULTS: Pupillary capture developed in 30 of the 764 patients (3.9%) having implantation of a posterior chamber IOL a mean of 14 weeks postoperatively (range 2 to 44 weeks). The incidence was significantly higher in eyes with angle-closure glaucoma, combined glaucoma and cataract surgery, can-opener capsulotomy, manual extraction, sulcus IOL implantation, large-optic IOLs, and one-piece IOLs. Neodymium:YAG laser treatment was successful in 8 of 12 eyes. CONCLUSION: Pupiliary capture may be anticipated and when recognized at an early stage, treated successfully with an Nd:YAG laser in most cases.     

Long-term results after drainage of premacular subhyaloid hemorrhage into the vitreous with a pulsed Nd:YAG laser

OBJECTIVE: To investigate the effects of drainage of premacular subhyaloid hemorrhage into the vitreous with an Nd:YAG laser in a large series of patients with long-term follow-up. METHODS: A retrospective review was conducted on 21 eyes with a circumscribed premacular subhyaloid hemorrhage of various causes. These eyes were treated with a pulsed Nd:YAG laser to drain the entrapped blood into the vitreous. The period of review ranged from 12 to 32 months (mean, 22 months). RESULTS: In 16 eyes, visual acuity improved within 1 month. Four eyes had persistent, dense, nonclearing vitreous opacity for at least 3 months and finally required vitrectomy. One clotted hemorrhage did not drain into the vitreous. Final visual outcome was determined by the underlying diagnosis, such as Valsalva retinopathy (7 eyes), diabetic retinopathy (7 eyes), branch retinal vein occlusion (4 eyes), and retinal macroaneurysm, Terson syndrome, or blood dyscrasia (1 eye each). Eyes with Valsalva retinopathy fared the best. Complications included a macular hole in 1 eye and a retinal detachment from a retinal break in a myopic patient. CONCLUSIONS: Drainage of premacular subhyaloid hemorrhage into the vitreous with an Nd:YAG laser is a viable treatment alternative for eyes with recent bleeding. However, a macular hole and a retinal detachment were observed as complications. Thus, to establish Nd:YAG laser treatment as a routine procedure, the risks and benefits have to be weighed in a randomized trial and compared with those of deferral of treatment or primary vitrectomy.     

Endoscopic Nd:YAG laser treatment of inoperable lower gastrointestinal cancer

Many patients with colorectal cancer are not amenable to curative resection at the time of presentation. Nevertheless, palliative resection still remains as the treatment of choice in the majority of patients. A small group of patients that are poor candidates for surgical resection may benefit from some non-surgical palliative procedures to relieve their symptoms. Electrocoagulation, cryosurgery and radiotherapy are some of the non-surgical procedure used and they are associated with high morbidity and mortality. The use of Neodymium: Yttrium-Aluminium-Garnet (Nd:YAG) laser photoablation to palliate patients with advanced colorectal carcinoma is well documented. It is associated with relatively low morbidity and perioperative mortality. It requires no anaesthesia and is the only non-surgical procedure that can be safely carried out above the peritoneal reflection. Nd:YAG laser had been used in some centres as a preresectional procedure in patient presenting with high grade obstruction. It allows proper bowel preparation followed by primary excision and anastomosis. As a palliative procedure, most patients showed rapid improvement in obstructive symptoms, bleeding and rectal discharge. The size of the lesion and circumferential extent of the tumour base correlate well with the response rate. Most patients remained asymptomatic before they succumb to the advanced disease. In our series, good palliation of obstructive symptoms was achieved in all obstructive cases with one laser treatment, bleeding tumours required an average of two sessions for complete haemostasis. In conclusion, Nd:YAG laser therapy is a safe and efficacious means for palliation of obstructive symptoms and bleeding in advanced rectal carcinoma.     

Nd:YAG laser irradiation of infected root canals in combination with microbiological examinations

In this in vivo study, 30 subjects with infected root canals were treated with the neodymium: yttrium-aluminum-garnet, or Nd:YAG, laser using standard laser settings and procedures. In microbiological examinations conducted before irradiation, the authors found streptococci in 30 cases and staphylococci in 15 cases. After the first irradiation, the authors found that 19 root canals showed minimal streptococcal growth and 10 root canals showed minimal staphylococcal growth.     

Retinal detachment in pseudophakic eyes with and without Nd:YAG laser posterior capsulotomy

OBJECTIVE: This study aimed to determine whether the characteristics of pseudophakic retinal detachment (RD) differ in eyes with and without a neodymium (Nd):YAG laser capsulotomy to identify features that might help to treat capsulotomy patients better. DESIGN: The study design was a retrospective cohort study of 129 consecutive eyes, 61 with a capsulotomy and 68 control eyes with an intact posterior capsule, in which a primary rhegmatogenous RD developed after a strictly uncomplicated extracapsular cataract extraction and intraocular lens implantation. SETTING: The study was conducted in a primary referral center. MAIN OUTCOME MEASURES: Number, type, and location of retinal breaks and type and extent of RD were measured. RESULTS: Risk factors predisposing to RD did not differ between the capsulotomy and control group. The median interval from cataract surgery to RD was expectedly longer in the capsulotomy group (4.1 years vs. 1.5 years, P < 0.001). The mean number of retinal breaks was larger in the capsulotomy group (1.7 vs. 1.1, P = 0.05), especially in upper quadrants (82 of 103 vs. 48 of 77, P = 0.024). Capsulotomy eyes also had a trend to have more atrophic holes that caused detachment relative to horseshoe breaks (34 of 103 vs. 15 of 77, P = 0.062). The type and extent of RD were similar in the two groups. CONCLUSIONS: This pilot study suggests that atrophic holes, particularly in the superior quadrants, may lead to RD preferentially after posterior capsulotomy. Early identification and treatment of such breaks might decrease the number of pseudophakic detachments after capsulotomy.     

Complications of posterior capsulotomy with the Nd:YAG laser. Study of 226 cases

BACKGROUND: Severe complications are classically described after capsulotomy: ocular hypertension, cystoid macular edema and secondary retinal detachment. PATIENTS AND METHODS: A series of 226 patients having sustained Nd:YAG laser (PC). Posterior capsulotomy has been studied retrospectively in order to determine the rate of early complications (24 hours after PC) and late complications (up to 6 months after the PC). RESULTS: Fifteen patients (6.6%) presented acute temporary intraocular hypertension, 2 patients (0.9%) a retinal detachment, 2 patients (0.9%) a cystoid macular edema (CME). A total number of complications of 8.4% was observed, 1.8% were heavy. CONCLUSIONS: Transient rise of intraocular pressure is seen. Prophylactic treatment with acetazolamide 500 mg (Diamox) and timolol (Timoptic) is necessary.     

Pathogenesis of systemic air embolism during bronchoscopic Nd:YAG laser operations

BACKGROUND: The occurrence of systemic air embolism during bronchoscopic neodymium:yttrium-aluminum garnet laser operations has been suspected. Here we describe its mechanism. METHODS: Two patients with embolic cardiac and neurologic complications after bronchoscopic neodymium: yttrium-aluminum garnet laser tumor ablation are described. A subsequent third patient was monitored for intracardiac and aortic air by transesophageal echocardiography. A review of the literature and safety recommendations are discussed. RESULTS: The appearance of systemic air emboli was related to the use of the laser fiber air coolant at high flow and resolved by decreasing the air flow. The presence of intracardiac and aortic air was associated with hypotension and inferior ischemic electrocardiographic changes. CONCLUSIONS: Systemic air embolism during bronchoscopic laser operations is a potentially catastrophic complication and is related to the use of gas-cooled laser fibers and contact probes. We recommend using the noncontact mode whenever possible and maintaining the coaxial coolant air flow at the minimum level or using a fluid coolant if contact is necessary.     

Nd:YAG laser therapy of recurrent epistaxis in hereditary hemorrhagic telangiectasia

BACKGROUND: Epistaxis is the leading symptom of hereditary hemorrhagic teleangiectasia (HHT). Over the last years several laser systems have been used for therapy. Only a few studies have published results of Nd:YAG laser therapy evaluating a larger number of patients. PATIENTS AND METHODS: From 1987 through 1996, forty-one patients with HHT were treated with a Nd:YAG laser due to recurrent epistaxis at the Department of Otorhinolaryngology of Kiel University. Thirty-two patients were followed-up over a period of at least 24 months. A centripetal technique was used for endonasal laser light application (15-25 Watts; 0.1-0.5 s), i.e., the laser light was applied from the periphery towards the center of the angiodysplasia. Intensive preoperative and postoperative nasal care with ointments was performed. RESULTS: Bleeding frequency and intensity decreased in 30 (94%) patients. Duration of the therapeutical success differed individually and varied from seven weeks to 14 months. Repeated laser therapy was necessary in 27 of 32 patients. CONCLUSION: The Nd:YAG laser is a suitable tool in the treatment of epistaxis in HHT. This procedure is less traumatic, less painful, and can be repeated multiple times. Nd:YAG laser therapy and other therapeutic options cannot obtain a lasting cure of Rendu-Osler-Weber syndrome. However, in the vast majority of cases recurrent nasal bleeding as the dominant symptom can be reduced in frequency as well as in intensity.     

Pulsed Nd:YAG laser welding of copper using oxygenated assist gases

The effects of using oxygenated assist gases on the weldability and weld properties of Nd:YAG, pulsed laser welds in copper (Cu) have been evaluated. It was found that the effective absorptivity of the Cu increased as the oxygen content of the Ar assist gas was increased. This facilitated laser welding of Cu at much lower laser powers and increased weld penetration. The use of oxygenated assist gas promoted nucleation and growth of submicroscopic oxide particles within the weld metal. These particles dispersion-strengthened the weld metal, thereby increasing both weld metal hardness and strength. However, when O₂ concentrations in the assist gas were greater than 90 pct, weld metal embrittlement due to excessive volume fractions of oxides was observed. The use of oxygenated assist gas also led to excessive cold lapping and poor bead quality. The bead quality was improved, however, by ramping-down the laser power before terminating each pulse.     

Oculoplastic surgery with a contact Nd:YAG laser silica scalpel. A case report

The purpose of this study was to evaluate the efficacy of local immunosuppression with intraportal administration of cyclosporine (CsA) in liver transplantation. Mongrel dogs weighing 12-18kg were used. Orthotopic liver transplantation was performed, and animals were divided to the following groups. Group I (n = 7): no treatment, group II (n = 7): CsA 5mg/kg/day intermittent iv, group III (n = 5): CsA 3mg/kg/day continuous iv and group IV (n = 8): CsA 3mg/kg/day continuous portal infusion. Immunosuppressive treatments were carried out for two weeks postransplant. Median survival time (MST) of group IV was significantly prolonged (MST = 18 days, range 10-85 days; p < 0.025) compared with group I (7 days, range 6-13), group II (10 days, range 7-16) and group III (7 days, range 6-10). Data of blood chemical analyses showed that hepatic dysfunction was significantly diminished in group IV compared with other groups (p < 0.05). Blood concentration of CsA on the 5th day (mean +/- SEM) was significantly lower in group IV (238 +/- 22ng/ml) than in group III (438 +/- 113ng/ml). Histologic findings showed that rejection reaction was effectively suppressed in group IV, although SG2M% (mean +/- SEM) of peripheral mononuclear cells of group IV (10.6 +/- 3.3%) was equal to that of group III (11.3 +/- 1.7%). In conclusion, local immunosuppression could achieve prominent effect in preventing hepatic graft rejection with limited systemic immunosuppression.     

Nd:YAG laser in the treatment of superficial lesions of the penis

In surgical treatment of benign and malignant lesions of the penis in addition to radicality also the demand of a favourable cosmetic result is stressed. The presented paper evaluates experience with the use of a Nd:YAG laser in condylomata acuminata and carcinoma of the penis. The author operated 51 men with condylomata acuminata of the glans, in 32 the external orifice of the urethra was affected. Treatment was successful in all patients with very good cosmetic results, relapses occurred in 11 patients. The author treated successfully also five patients with carcinoma of the penis classified as TIS and T1. In none of the patients a relapse was observed after a mean follow-up period of 15.4 months.     

Bactericidal effect of the Nd:YAG laser in in vitro root canals

The spatio-temporal patterns of neural activity evoked by electrical stimuli to the antennal nerve (AN) in male cockroach antennal lobes (ALs) in vivo were analyzed by optical imaging using a voltage-sensitive dye. The response pattern was initially a depolarization on the AN and subsequently a depolarization followed by a hyperpolarization on the whole area of macroglomerulus (MG) and a part of ordinary glomerulus (OG). It was suggested by the pharmacological results that the depolarizing responses on the AL consist of both a presynaptic response, representing synchronous compound action potentials from the AN, and a postsynaptic response, representing synchronous compound excitatory postsynaptic potentials and action potentials from neurites of AL neurons, and that the inhibitory responses of GABAergic local interneurons in the AN are different in time course from that in the AL.     

A clinical analysis of pupillary membrane formation after intraocular lens implantation

In 540 cases having undertaken extracapsular cataract extraction and intraocular lens implantation, a pupillary membrane developed in 76 cases, the rate of occurrence being 14%. Generally, the membrane appears on the fifth post-operative day and corticosteroids are effective in its treatment. After treatment no significant sequela is left and the corrected postoperative visual acuity is not affected. The pathogenesis, treatment and prognosis of the pupillary membrane are briefly discussed in the report.     

Physical-mechanical effects of Nd:YAG laser on the surface of sound dental enamel

We present our experience with 55 children in which we performed flexible fiberoptic bronchoscopy (FFB) using an Olympus BF3C20 instrument and by using sedation and local anaesthesia or laryngeal mask airway. Indications for performing this procedure were stridor, opportunist or recurrent pneumonia, persistent atelectasis, a suspected foreign body, confirmation of endobronchial tuberculosis and evaluation of tracheostomy. In 70% of the cases, the diagnosis was made by the FFB and 14 cases were normal. One child with severe hypoxia presented respiratory arrest and need intubation. Our results suggest that FFB is safe, has advantages over rigid bronchoscopy, avoids general anaesthetic and with laryngeal mask airway is possible to perform in patients of every age.     

Water jet guided Nd:YAG laser coagulation--its application in the field of gastroenterology

With the water jet guided laser, a comparatively new transmission system has become available, with the aid of which the laser beam is conducted from the end of the transmission fibre of the conventional light guide system to the target tissue via a water jet. The extra costs of this modality are low. The technique is easy to apply, and is associated with a number of technical advantages, such as absence of smoke and carbonisation, reduction in organ distension, etc. The water jet guided laser brings about volume coagulation in the deeper layers of the wall, with concomitant oedema and hyperaemia in the periphery. In a randomised, prospective controlled study, 89 patients with gastroduodenal ulcers bearing a visible vessel were treated with the Nd:YAG laser (wavelength 1.064 nm), 43 with the non-contact, and 46 with the water jet guided modality. In the water jet group a smaller number of bleedings were induced (p < 0.05) and fewer failures, emergency operations and deaths occurred. The technical advantages of the method, together with the results of treatment in 20 tumour patients with adenomas (n = 6) and adenocarcinomas in the colorectum (n = 14) with readily achievable tumour debulking (n = 13) or complete eradication (n = 7), suggest that the use of the water jet guided laser might also be appropriate for the treatment of tumours.     

Increased cataract rate and characteristics of Nd:YAG laser capsulotomy in retinitis pigmentosa

BACKGROUND: Retinitis pigmentosa (RP) is associated with the development of a posterior subcapsular cataract (PSC). The development of posterior capsule opacification (PCO) after cataract surgery and a decrease of central visual acuity is sometimes misinterpreted by the patients as natural course of RP. Therefore, therapeutic intervention is often delayed. PATIENTS AND METHODS: In a retrospective study (part 1) the incidence of PCO was evaluated in a group of 26 RP patients who underwent cataract surgery and IOL implantation. In a prospective analyse (part 2) PCO was quantified in 13 RP patients using the standardized photographic technique and image analysis system introduced by Tetz et al. Matched pairs were formed with a control group of 13 patients without retinal disease who matched the RP group in terms of age distribution and postoperative follow-up time. In part 3 the parameters of Nd:YAG laser capsulotomy in 12 RP patients and 14 controls were evaluated. RESULTS: Part 1: The cumulative PCO rate in RP at the end of the first postoperative year was 14.6%, 26.8% in the second, 53.7% in the third and 70.7% after the third year. Nd:YAG laser capsulotomy was performed in 70% of eyes (after 18.4 +/- 14.7 months). In eyes with significant PCO development 70% had PSC preoperatively, while in eyes without PCO formation only 41.7% showed PSC. Part 2: The matched pairs analysis showed a significantly higher PCO value for RP patients (2.11 +/- 1.42) than for the control group (0.89 +/- 0.72) (P = 0.038). Part 3: Average Nd:YAG laser energy levels were 12.8 +/- 11.2 MJ (RP) and 7.6 +/- 6.7 MJ (control). Some 25% of RP patients required further laser treatment of regrown secondary cataract. CONCLUSIONS: Patients with RP showed a significantly higher incidence and density of PCO. Whether RP-specific pathomechanisms are responsible for this needs further investigation.