The high-pressure bleb.

A 45-year-old male presented with a slowly progressive, painless swelling in his right eye for the past 6 months. He had undergone an open globe injury repair 10 years back and an eventful cataract surgery 5 years back. The presenting visual acuity in the affected eye was perception of light with inaccurate projection of rays. The intraocular pressure was 44 mm Hg with advanced glaucomatous cupping. The swelling was identified to be a communicating sub-tenon cyst secondary to scleral wound dehiscence from secondary angle closure glaucoma. Wound re-suturing, cyst excision and diode laser cyclophotocoagulation was performed in a single sitting, with explained poor visual prognosis.

Ipsilateral transient amaurosis, mydriasis and light reflex absence after subconjunctival local anesthesia with mepivacaine in three patients with refractory glaucoma - a case report.

BACKGROUND: The subconjunctival anesthesia with local anesthetics is considered as a low-risk procedure allowing ocular surgery without serious complications typical for retro- or parabulbar anesthesia, especially in patients with preexisting Optic Nerve damage. We report development of ipsilateral transient amaurosis accompanied with mydriasis and both, direct and consensual light response absence. CASE PRESENTATION: Three patients with advanced refractory glaucoma undergoing laser cyclophotocoagulation (CPC) for intraocular pressure lowering experienced these adverse effects just few minutes after subconjunctival injection of mepivacaine 2% solution (Scandicaine® 2%, without vasoconstrictor supplementation). The vision was completely recovered to usual values in up to 20 h after mepivacaine application. Extensive ophthalmological examination, including cranial magnetic resonance imaging (MRI), revealed no further ocular abnormalities, especially no vascular constriction or thrombotic signs as well as no retinal detachment. The oculomotor function remained intact. The blockade of ipsilateral ciliary ganglion parasympathetic fibers by mepivacaine may be the responsible mechanism. Systemic pathways as drug-drug interactions seem to be unlikely involved. Importantly, all three patients tolerated the same procedure previously or at a later date without any complication. Overall, our thoroughly elaborated risk management could not determine the causative factor explaining the observed ocular complications just in the current occasion and not at other time points. CONCLUSIONS: Doctors should be aware and patients should be informed about such rare complications after subconjunctival local anesthetics administration. Adequate risk management should insure patients' safety.

[Evaluating the effectiveness and safety of diode laser trans-scleral thermotherapy of the ciliary body as a treatment for refractory glaucoma].

OBJECTIVE: To evaluate the effectiveness and safety of diode laser trans-scleral thermotherapy (TSTT) in cyclodestruction for refractory glaucoma (RG). MATERIAL AND METHODS: The proposed cyclodestructive procedure was performed on 87 patients with severe and terminal RG (stages III and IV) at power levels of 0.4-0.5 W with exposure times of 15-25 seconds. RESULTS: The incidence of severe inflammatory response was less than that after well-known cyclodestructive procedures. The average reduction of intraocular pressure at the first day after surgery (considering all observations) was 10.45 +/- 7.23 mmHg. In all cases after TSTT of the ciliary body the pain resolved within the first day. CONCLUSION: The effectiveness of the new method is comparable to that of other methods of cyclodestruction, however, the proposed TSTT technique is much safer than the conventional trans-scleral cyclophotocoagulation.

Low-dose transscleral diode laser cyclophotocoagulation (TSCPC) as a potential single treatment for primary open-angle glaucoma (POAG) in Malawi?

PURPOSE: To investigate if low-dose 810 nm transscleral cyclophotocoagulation (TSCPC) can be used as single treatment in Malawian glaucoma patients. METHODS: Forty-seven eyes of 28 patients with primary open-angle and pseudoexfoliation glaucoma were treated with TSCPC using 12 spots with 900 mW, 2,000 ms (1.8 J per spot); six spots in the upper half, six in the lower by sparing the 3 and 9 o'clock positions ±20°. Intraocular pressure (IOP) and uncorrected visual acuity (UVA) were measured by an independent examiner preoperatively, on the first postoperative day, after 2 weeks, and after 3 months. RESULTS: Twenty-four (86%) and 18 (64%) of 28 patients (31 of 47 eyes; 66%) completed follow-up at 2 weeks and at 3 months respectively. After a single treatment session, IOP decreased by at least 25 % in 88% (21 of 24) after 2 weeks, and in 50% (nine of 18) of patients after 3 months. Mean IOP was 38.5 mmHg before TSCPC, 23.5 mmHg (p < 0.001) after 1 day, 24.5 mmHg (p < 0.001) after 2 weeks, and 35.6 mmHg (p = 0.37) after 3 months. In three patients, however, IOP increased after 3 months to levels significantly higher than before TSCPC. CONCLUSION: Low-dose TSCPC caused a significant IOP lowering for up to 2 weeks (15 mmHg less from baseline) in most patients. After 3 months, this effect was stable in 50% of patients; in the other half, IOP nearly returned back to baseline.

The effect of indocyanine green pretreatment on the parameters of transscleral diode laser thermotherapy-induced threshold coagulation of the ciliary body.

BACKGROUND AND OBJECTIVE: To study the effect of indocyanine green (ICG) pretreatment on threshold parameters of transscleral diode laser thermotherapy-induced threshold coagulation of the ciliary body. The procedure was termed 'cyclothermotherapy' based on the long duration (15-60 seconds) of diode laser application. STUDY DESIGN/MATERIALS AND METHODS: The right eyes of nine young adult New Zealand white rabbits underwent transscleral cyclothermotherapy (TCT, Group 1), TCT following ICG pretreatment (Group 2), and external manipulation of the ciliary body alone (Group 3). Rabbits were sacrificed after 24 hours; specimens were evaluated with gross examination and light microscopy. RESULTS: Thresholds were 30 J/cm2 (TCT) and 4.5 J/cm2 (TCT with ICG). Widespread structural damage was seen in the ciliary processes and the ciliary body in Groups 1 and 2. In Group 3, external manipulation of the ciliary body caused hemorrhage and structural damage confined to the ciliary processes. CONCLUSION: ICG pretreatment reduced the energy necessary to cause a threshold lesion with TCT in nonpigmented rabbits.

[Subconjunctival anaesthesia using cocaine or mepivacaine for cyclocryotherapy in advanced glaucoma]. / Subkonjunktivale Anästhesie mit Kokain oder Mepivacain bei der Zyklokryokoagulation zur Behandlung fortgeschrittener Glaukome.

BACKGROUND: Retro- or peribulbar anaesthesia are the standard procedures for cyclodestructive surgery. Because these methods of anaesthesia may further compromise optic nerve function, especially in advanced glaucoma, subconjunctival anaesthesia was evaluated as an alternative procedure in cyclocryotherapy. PATIENTS AND METHODS: 1. To evaluate the current methods of anaesthesia a questionnaire was sent to all University Eye Clinics in Germany in 2001. 2. A prospective, consecutive study concerning cyclocryotherapy in advanced glaucoma was started using subconjunctival anaesthesia with 5 % cocaine or, alternatively, 2 % mepivacaine in 25 eyes of 25 patients in each group. Pain during cyclocryotherapy was recorded using a 10-point rating-scale (1 = no pain to 10 = intolerably severe pain) and adverse events were also recorded. RESULTS: 1. 88.6 % of the University Eye Clinics in Germany replied to our questionnaire. In 2001 cyclocryotherapy was performed in 80.6 % of the University Eye Clinics in Germany (Tübingen not included), 16.1 % among them solely used cyclocryotherapy for the treatment of advanced glaucoma. 2. Using 5 % cocaine for subconjunctival anaesthesia - 92 % of patients experienced no pain and 8 % of patients reported very mild pain during cyclocryotherapy. One patient reported nausea, 4 patients mouth dryness. After anaesthesia with mepivacaine - 80 % experienced no pain, 12 % very mild pain, and 8 % mild pain. There were no systemic side effects. CONCLUSION: Most of the patients experienced no pain during cyclocryotherapy using subconjunctival anaesthesia with cocaine or mepivacaine. Therefore, risks and side effects of retro- or parabulbar anaesthesia can be successfully avoided by this simple modification.

Retrobulbar catheter technique for postoperative titratable analgesia after glaucoma surgery.

PURPOSE: To assess an indwelling retrobulbar catheter for delivery of intraoperative anesthesia and postoperative analgesia in patients undergoing painful cyclodestructive and retinal destructive procedures as treatment of neovascular glaucoma. PATIENTS AND METHODS: The prospective clinical interventional study included all 11 patients undergoing cyclocryocoagulation and/or retinal exocryocoagulation as treatment of neovascular glaucoma due to proliferate ischemic retinopathies. Using a commercially available retrobulbar needle with a diameter of 0.80 mm and a length of 38 mm, 7 mL of a local anesthetic were injected. Through the same needle, a 28-gauge commercially available flexible catheter was introduced into the retrobulbar space, the needle was withdrawn, and the catheter was fixed in place. When the patients began to feel pain during or after surgery, 2 mL of a local anesthetic were reinjected through the catheter. The catheter was removed 24 hours after surgery. RESULTS: Due to increasing pain in the postoperative period, 8 (72.7%) patients received a reinjection 156.3 +/- 94.6 minutes after the preoperative injection. Seven (63.6%) patients requested a second reinjection 268.6 +/- 45.7 minutes after the preoperative injection, and three (27.3%) patients requested a third postoperative injection 333.3 +/- 79.1 minutes after the preoperative injection. Reinjection of the local anesthetic through the catheter markedly decreased the pain within 5 minutes of injection in all patients. CONCLUSIONS: Avoiding side effects of systemic analgesics and sedatives, an indwelling retrobulbar catheter for repeat postoperative injections of local anesthetics is useful and effective for titratable postoperative analgesia after painful cyclodestructive or retinal destructive surgery as treatment of neovascular glaucoma.

Subconjunctival anesthesia in contact diode laser cyclophotocoagulation.

BACKGROUND: Retro- or peribulbar anesthesia are the standard procedures for cyclodestructive surgery. Because these methods of anesthesia may further compromise optic nerve function, especially in advanced glaucoma, subconjunctival anesthesia was evaluated as an alternative procedure in contact diode laser cyclophotocoagulation (CPC). PATIENTS AND METHODS: A prospective study concerning diode laser CPC in advanced glaucoma was started using subconjunctival anesthesia with 2% mepivacaine. Complications and pain during CPC (5 point rating scale) and on the first postoperative day were recorded. Only the first CPC in every patient was included for evaluation. RESULTS: Included in the study were 120 eyes of 120 patients. During CPC, 82.5% of patients experienced no pain, 11.7% mild pain, and 5.8% moderate pain. No instances of pain or excess motion occurred that required peribulbar anesthesia or discontinuation of the procedure. CONCLUSION: Most of the patients experienced no pain during diode laser CPC using subconjunctival anesthesia. Therefore, risks and side effects of retro- or peribulbar anesthesia can be successfully avoided by this simple modification.

[Transient blindness after subconjunctival anesthesia for diode laser cyclophotocoagulation]. / Transiente Erblindung nach subkonjunktivaler Anästhesie zur Diodenlaser-Zyklophotokoagulation bei fortgeschrittenen Glaukomen.

BACKGROUND: Retro- and parabulbar anaesthesia can be associated with severe sight-threatening and life-threatening complications and may compromise optic nerve function, especially in eyes with advanced optic neuropathy. Subconjunctival anaesthesia usually does not influence optic nerve function. We report on two patients who developed transient amaurosis after subconjunctival anaesthesia. PATIENTS: In two patients (75 and 77 years old) with advanced refractory glaucoma a diode laser cyclophotocoagulation was performed to lower the increased IOP. For local anaesthesia, 2 ml of 2% mepivacaine was placed beneath the conjunctiva. The needle was placed at least 6 mm from the limbus to avoid bleeding at the injection site near the limbus. After 10 minutes, both patients observed a decrease of their vision of the treated eyes. A few minutes later, an amaurosis of the treated eyes was found in both patients, which was fully reversible after 2 to 3 hours. At fundus examination, no vessel occlusion was seen. CONCLUSIONS: Subconjunctival anaesthesia may cause transient blindness in patients with advanced optic neuropathy. The incidence of this side effect seems very low.

Aceclidine effects on outflow facility after ciliary muscle disinsertion.

Aceclidine increases outflow facility with little accommodative effect. To determine whether this dissociation resides in the ciliary muscle (CM) or trabecular meshwork (TM), we measured aceclidine effects on perfusion outflow facility in both eyes of 8 rhesus monkeys after unilateral disinsertion of the CM from the TM. Facility in the control eyes increased by approximately 250% following intravenous pilocarpine and by an additional approximately 250% following intracameral pilocarpine, relative to baseline and uncorrected for washout. In CM-disinserted eyes, the facility response to intravenous and intracameral pilocarpine averaged approximately 25% of that in contralateral controls. Cytochalasin B, which acts directly on the TM to increase facility but is not additive to maximal pilocarpine doses in normal eyes, had no additional effect beyond that of pilocarpine in control eyes but induced an additional 100% facility increase relative to baseline in CM-disinserted eyes. The accommodative response to carbachol in CM-disinserted eyes was approximately 80% of that in contralateral controls, consistent with retention of CM contractility and the gonioscopic appearance of shallow CM disinsertion. Intracameral aceclidine HCl doses of 5 and 50 micrograms increased outflow facility by approximately 80 and 250%, respectively, in control eyes, and by approximately 0 and 80% in CM-disinserted eyes. Either the low aceclidine dose affected facility via the CM, while the high dose exerted an additional effect on the TM, or aceclidine acted only via the CM, with the low dose being ineffective and the high dose modestly effective in CM-disinserted eyes because only a few CM-TM attachments remained.

Complete but transient visual loss after yttrium aluminum garnet laser transscleral cyclocoagulation.

We report the case of a patient who had no light perception after neodymium:yttrium aluminum garnet (Nd:YAG) laser transscleral cyclocoagulation. To the best of our knowledge, no similar cases have been reported previously. A 56-year-old man with intractable open-angle glaucoma had intraocular pressures of 42 mmHg OD and 35mmHg OS. The patient rejected a recommended filtering operation, although argon laser trabeculoplasty and maximal medication had been ineffective OU. We used the free-running mode of an Nd:YAG laser to treat this patient. After the tenth application, the patient suddenly noticed acute visual loss OD. He was admitted to the hospital immediately. His retinal vessels and papilla OD could not be seen during fluorescein angiography. We administered pulsed corticosteroids and a stellate ganglion block. Gradually, his symptoms improved. The indications for using Nd:YAG laser cyclocoagulation have been expanded. However, as a result of our experience in this patient, we concluded that such therapy should be limited to cases not amenable to other forms of medical and surgical treatment.

[Contact cyclophotocoagulation with the continuous wave Nd:YAG laser with quartz fiber. Optimizing coagulation parameters]. / Kontaktzyklophotokoagulation mit dem Dauerstrich-Nd:YAG-Laser über Quarzfaser. Optimierung der Koagulationsparameter.

Transscleral cyclo-photocoagulation with a cw-Nd:YAG-laser was studied in enucleated porcine eyes with application times of between 10 ms and 1.5 s. Contact coagulation via a quartz fiber (core 600 microns) required about 32% less power to create visible ciliary body coagulation compared to non-contact coagulation via a focusing handpiece. Application of focusing fiber tips led to a further reduction in the coagulation threshold by a factor of 0.6. The energy per laser application required for ciliary body coagulation increased with application time. During contact coagulation using plane fiber tips a pronounced temperature rise was sometimes observed at the fiber tip due to deposits of carbonized tissue with the subsequent risk of scleral damage. In a pilot study five eyes with secondary glaucoma were treated under coagulation conditions found to be optimal (8 W at 0.2 s).

[Cryotherapy for glaucoma (author's transl)]. / Kälteanwendung bei Glaukom.

After a short survey of the development of thermosurgery for glaucoma our own experiences with 120 cryocoagulation operations of the ciliary body are described. We observed postoperatively a general reduction of intraocular pressure--but pressure regulation appeared in only 1/3 of cases.