**7. Combined phacoemulsification−Ex-PRESS GDD**

The Ex-PRESS GDD works differently compared to the GDDs described above. It is a miniature stainless steel non valved GDD with 0.4mm external diameter and 50 or 200 µm internal diameter depending on the model. It has a length of 2.4 – 3.0 mm, it is safe in magnetic fields up to 3 Tesla [92,93] and does seem to interfere with the quality of the MRI images of the orbit [94].

**•** Ex-PRESS inserted at the blue transition zone between clear cornea and sclera (corresponds to juxtacanalicular meshwork) with the use of a 25G needle. The direction of the needle must be parallel to the iris plane. The needle is advanced until it is clearly seen in the anterior

**Figure 7.** Ex-PRESS GDD indenting the iris (arrow) without any adverse effects and excellent IOP control(courtesy of

Combined Cataract-Glaucoma Surgery http://dx.doi.org/10.5772/54808 495

**•** Tying of the scleral flap releasable sutures (more sutures can be used according to the

**•** Triamcinolone injection subconjunctivally 0.1 ml behind the scleral flap at the end of the

As the insertion of the Ex-PRESS GDD is a small trabeculectomy the postoperative manage‐

As the Ex-PRESS mini GDD is a modification of trabeculectomy and the aqueous dynamics are similar the complications from its insertion are similar to that of trabeculectomy. Compli‐ cations specific to the technique include obstruction of the GDD by blood, fibrin and vitreous. The device may also touch the iris and can be repositioned via another track (fig 7). The track can be done under the same sclera flap next to the initial one. Mal-positioned devices do not need to be re-inserted if they are symptom free and offer adequate hypotensive effect (fig 8). The Ex-PRESS mini shunt may be blocked by fibrin, blood or vitreous. YAG laser is an excellent

The Ex-Press GDD is at least as effective as TM in terms of long term IOP control and number of postoperative antiglaucoma drops. It also has lower complication rate compared to

**•** Conjunctival closure with 10/0 nylon sutures as in trabeculectomy.

chamber

Prof Kozobolis)

operation.

**7.7. Complications**

**7.8. Outcomes**

surgeon's discretion).

**7.6. Postoperative management**

ment is the same as for trabeculectomy.

tool which can be used to remove the blockage [95].

#### **7.1. Indications**


#### **7.2. Aqueous humor dynamics in Ex–PRESS GDD**

The Ex-PRESS GDD is an alternative to trabeculectomy as it only replaces the internal ostium and negates the need for a peripheral iridectomy. The aqueous flows through the GDD in the subconjunctival/sub-Tenon's space and forms a filtering bleb.

#### **7.3. Antimetabolites**

The insertion of the Ex-PRESS GDD can be augmented with the intraoperative application of MMC in order to reduce conjunctival scarring and improve bleb survival

#### **7.4. Corticosteroids**

As with trabeculectomy the authors augment the operation with the injection of 0.1 ml of triamcinolone under the conjunctiva behind the scleral flap at the end of the operation. Standard postoperative care includes the use of topical steroids and antibiotics.

#### **7.5. Surgical technique**

**•** The initial steps for the combined phaco- Ex-PRESS GDD procedure are the same as for trabeculectomy up to the creation of the track for the insertion of the mini shunt

**Figure 7.** Ex-PRESS GDD indenting the iris (arrow) without any adverse effects and excellent IOP control(courtesy of Prof Kozobolis)


#### **7.6. Postoperative management**

As the insertion of the Ex-PRESS GDD is a small trabeculectomy the postoperative manage‐ ment is the same as for trabeculectomy.

#### **7.7. Complications**

3-6 weeks as fibrous tissue is forming around the plate. The IOP must be lowered with topical antiglaucoma medication or even acetozolamide tablets. Needling of the fibrous capsule with 30G needle may be tried with injection of dexamethasone and 5FU as for trabeculectomy.

The combined surgery does not seem to adversely affect the hypotensive effect of the GDD [91].

The Ex-PRESS GDD works differently compared to the GDDs described above. It is a miniature stainless steel non valved GDD with 0.4mm external diameter and 50 or 200 µm internal diameter depending on the model. It has a length of 2.4 – 3.0 mm, it is safe in magnetic fields up to 3 Tesla [92,93] and does seem to interfere with the quality of the MRI

**•** Is not the best option in congenital glaucomas as it is a new procedure and the concomitant

The Ex-PRESS GDD is an alternative to trabeculectomy as it only replaces the internal ostium and negates the need for a peripheral iridectomy. The aqueous flows through the GDD in the

The insertion of the Ex-PRESS GDD can be augmented with the intraoperative application of

As with trabeculectomy the authors augment the operation with the injection of 0.1 ml of triamcinolone under the conjunctiva behind the scleral flap at the end of the operation.

**•** The initial steps for the combined phaco- Ex-PRESS GDD procedure are the same as for

trabeculectomy up to the creation of the track for the insertion of the mini shunt

**•** In case of narrow angles there may not be enough room to fit the mini implant

use of antimetabolites may cause problems in the long run in young patients.

**7. Combined phacoemulsification−Ex-PRESS GDD**

**7.2. Aqueous humor dynamics in Ex–PRESS GDD**

subconjunctival/sub-Tenon's space and forms a filtering bleb.

MMC in order to reduce conjunctival scarring and improve bleb survival

Standard postoperative care includes the use of topical steroids and antibiotics.

**6.7. Outcomes**

494 Glaucoma - Basic and Clinical Aspects

images of the orbit [94].

**•** Open angle glaucomas

**7.3. Antimetabolites**

**7.4. Corticosteroids**

**7.5. Surgical technique**

**7.1. Indications**

As the Ex-PRESS mini GDD is a modification of trabeculectomy and the aqueous dynamics are similar the complications from its insertion are similar to that of trabeculectomy. Compli‐ cations specific to the technique include obstruction of the GDD by blood, fibrin and vitreous. The device may also touch the iris and can be repositioned via another track (fig 7). The track can be done under the same sclera flap next to the initial one. Mal-positioned devices do not need to be re-inserted if they are symptom free and offer adequate hypotensive effect (fig 8). The Ex-PRESS mini shunt may be blocked by fibrin, blood or vitreous. YAG laser is an excellent tool which can be used to remove the blockage [95].

#### **7.8. Outcomes**

The Ex-Press GDD is at least as effective as TM in terms of long term IOP control and number of postoperative antiglaucoma drops. It also has lower complication rate compared to

**•** Formation of a 5×5 mm superficial scleral flap at 50% of sclera thickness

window as for DS

**•** Excision of the deep scleral flap

dilate the canal and create microruptures in the wall.

tied on the tip and the microcatheter is pulled back

together to provide moderate tension on the canal.

**•** Conjunctiva is sutured with 10/0 Nylon

**10. Solx gold microshunt (GMS)**

channels and the distal end 10 channels 50 µm each

**•** The superficial flap is tied securely to the sclera with 10/0 Nylon

insertion

SC

**9.2. Outcomes**

than trabeculectomy [105].

**9.3. Complications**

membrane detachment

**•** Formation of a 4×4 mm deep scleral flap extending into clear cornea to create a Descemet's

Combined Cataract-Glaucoma Surgery http://dx.doi.org/10.5772/54808 497

**•** Clear cornea phacoemulsification from a temporal approach with injectable intraocular lens

**•** Insertion of a microcatheter in one of the two cut ends of Schlemm's canal (iTrack 250A) **•** The microcatheter is pushed around SC with injection of sodium hyaluronate in order to

**•** The microcatheter has a light at its tip so that the surgeon can follow it as it is driven around

**•** When the tip of the microcatheter emerges at the other cut end of SC a 10/0 Nylon suture is

**•** When the tip of the microcatheter emerges from the cut end of SC the two ends are tied

Combined phaco-canalostomy provides slightly better hypotensive effect and less antiglau‐ coma drops than canalostomy alone [103,104]. Compared to trabeculectomy it offers lower but not statistically significant hypotensive effect and requires more antiglaucoma medication

The most common complications are hyphaema, peripheral anterior synechiae, Descemet

The GMS is a flat-plate non valved drainage device which is inserted in the suprachoroidal space and increases uveoscleral outflow. It is made of 24 karat gold and its dimensions are 3.2 mm wide, 5.2 mm long and 44µm thick. The aqueous enters the device from the proximal side which contains 60 holes 100 µm each. The device contains 10 open and 9 closed channels (width of lumen 24µm and height 50µm) and at the distal end the fluid exits in the suprachoroidal space via a grid of 117 holes on either side. The proximal end of the GMS contains 12 additional

**Figure 8.** Ex-PRESS GDD (arrow) inserted through a patent peripheral iridectomy in posterior chamber with excellent IOP control (courtesy of Prof Kozobolis)

trabeculectomy [96-101].The combined phaco-Ex-PRESS operation has the hypotensive effect as the simple insertion of the device [102].
