Wound construction in manual small incision cataract surgery Nucleus management with Blumenthal technique: Anterior chamber maintainer

• Status of the sclera: It is imperative to look at the status of sclera before one plans for scleral wound construction. Cases with thin sclera such as high myopia, osteogenesis imperfecta, Ehler Danlos Syndrome, healed scleritis are relative contraindications for scleral wound construction. • Incision with 15 No. Blade : Surgeon needs to make the scleral bed dry with the help of cott on bud as making the incision on a relatively wet scleral bed can lead to splaying of the scleral fi bers leading to irregular astigmatism. • Placement of the crescent knife: The horizontal shaft of the crescent knife needs to be touching close to the sclera (sclera posterior to wound) while dissecting the scleral bed with the knife as it will lead to minimum complications; if it is not abutt ing close to sclera and if the horizontal shaft is away from posterior sclera it can lead to premature entry. • Formation of the anterior chamber with viscoelastic agent: Surgeon needs to form the anterior chamber with viscoelastic agent or to switch on the anterior chamber maintainer if one is doing MSICS by Blumenthal technique, in order to achieve smooth dissection of scleral bed. Hypotonus globe can act as determinant for smooth tunnel construction. At the same time, one needs to be careful not to overfi ll the anterior chamber as it can lead to premature entry. • Author mentions that the crescent blade should be cutt ing while being brought out of the tissue,[1] but there is no mention about the cutt ing of sclera with keratome. All the cutt ing needs to be done while the keratome is moving forward into the scleral tissue in order to prevent irregular astigmatism. • In cases with premature entry or with leak from the tunnel the suturing needs to be done by using ‘fi gure of 8’ or ‘infi niti’ suture.


Wound construction in manual small incision cataract surgery
Dear Editor, I read the article on wound construction in manual small incision cataract surgery (MSICS) by Haldipurkar et al. [1] The authors need to be complimented for their candid expositions on scleral wound construction in widely done SICS. I will like to add a few comments on scleral wound construction in MSICS: • Status of the sclera: It is imperative to look at the status of sclera before one plans for scleral wound construction.
Cases with thin sclera such as high myopia, osteogenesis imperfecta, Ehler Danlos Syndrome, healed scleritis are relative contraindications for scleral wound construction. • Incision with 15 No. Blade : Surgeon needs to make the scleral bed dry with the help of cott on bud as making the incision on a relatively wet scleral bed can lead to splaying of the scleral fi bers leading to irregular astigmatism. • Placement of the crescent knife: The horizontal shaft of the crescent knife needs to be touching close to the sclera (sclera posterior to wound) while dissecting the scleral bed with the knife as it will lead to minimum complications; if it is not abutt ing close to sclera and if the horizontal shaft is away from posterior sclera it can lead to premature entry. • Formation of the anterior chamber with viscoelastic agent: Surgeon needs to form the anterior chamber with viscoelastic agent or to switch on the anterior chamber maintainer if one is doing MSICS by Blumenthal technique, in order to achieve smooth dissection of scleral bed. Hypotonus globe can act as determinant for smooth tunnel construction. At the same time, one needs to be careful not to overfi ll the anterior chamber as it can lead to premature entry. • Author mentions that the crescent blade should be cutt ing while being brought out of the tissue, [1] but there is no mention about the cutt ing of sclera with keratome. All the cutt ing needs to be done while the keratome is moving forward into the scleral tissue in order to prevent irregular astigmatism. • In cases with premature entry or with leak from the tunnel the suturing needs to be done by using 'fi gure of 8' or 'infi niti' suture.
Incorporation of the above intraoperative surgical tips into one's surgical armamentarium will ensure a safer and smooth MSICS for the novice surgeon.

Nucleus management with Blumenthal technique: Anterior chamber maintainer
Dear Editor, I read with interest the article by Malik et al. on nuclear management with Blumenthal technique [1] and in the context of the article would like to comment on a few points. The article is titled "Nucleus management with Blumenthal technique", however, in the whole article the original technique described by the late Prof Michael Blumenthal is missing.
Blumenthal had elegantly described the use of anterior chamber maintainer in extracapsular cataract extraction and manual small-incision cataract surgery (SICS). [2][3][4] In the paragraph on nuclear delivery, [1] the authors have stated the use of viscoelastic to facilitate nucleus delivery [1] but the original Blumenthal technique described the use of viscoelastic agent only in diffi cult cases, in case of complications during manual SICS. [2][3][4] According to Blumenthal, anterior chamber maintainer in itself provides suffi cient anterior chamber depth and fl uidics in facilitating nucleus prolapsed in anterior chamber and subsequently, Sheet's glide aids in smooth atraumatic delivery of nucleus. [4] Blumenthal has described use of smooth round-tipped Blumenthal cannula for hydrodissection which is very diff erent from the conventional sharp-tipped hydrodissection cannula. The original hydrodissection technique described by Blumenthal entails the hydrodissection of superior 12 o'clock pole through side port incision by Blumenthal cannula followed by supplemented hydrodissection at 3 o'clock and 9 o'clock pole which facilitates superior pole of the nucleus to pop out of the bag which is subsequently pushed out into the anterior chamber followed by maneuvering out the remaining nucleus with the help of the Blumenthal canula only. At no step is the use of viscoelastic agent advocated. [3] Similarly, during removal of the cortex Blumenthal has again described the use of single-port cannula along with anterior chamber maintainer and has not advocated use of viscoelastic agent. The diagrammatic representation showing the frown incision in Fig. 1 is also not described by Blumenthal, he has advocated the use of straight incision of maximum size 5 mm with back cuts on either side of straight incision of length up to 1.5 mm, with 100-110 degrees angulation with straight incision, and further dissection of the tunnel under anterior chamber maintainer only without using viscoelastic agent. [3] I have been practicing and teaching the original Blumenthal technique since the last six years and have been fairly successful in using the originally described Blumenthal technique. Reading all the aspects of small-incision cataract surgery in a single issue was indeed a pleasure. Malik et al. [1] have described the original Blumenthal technique very eloquently and have added their personal modifi cation.

Rupesh Agrawal
We would like to put forth the following observation. 1) Small-incision cataract surgery (SICS) is considered as a cost-saving procedure and is suitable for the developing world. [2] Viscoelastic devices may not be required in most of the cases thus reducing the cost of surgery further. Under the anterior chamber maintainer (ACM) all the intraocular steps of SICS can be done with anterior chamber remaining deep. They include: capsulorrhexis, hydrodissection, prolapse of nucleus to anterior chamber, nucleus delivery, cortical matt er removal, posterior capsule polish (with aspiration cannula attached to the syringe without plunger), [3] and intraocular lens implantation. 2) Use of Sheet's glide [4] can be conveniently omitt ed as they are single-use devices, and add to the cost. The authors have suggested an iris repositor as an alternate to Sheet's glide. The hydrostatic force of fl uid in the anterior chamber guides the nucleus to the wound by just pressing the wound with McPherson forceps with tongues open, thus avoiding use of an iris repositor. Additionally, during this procedure the iris repositor being a hard instrument increases the chances of breaking the posterior capsule when it lies behind the lens material as the anterior chamber also marginally shallows. 3) When the nucleus is engaged in the incision and not being delivered out, a Sinskey hook (usually a part of the cataract tray) can be used to wheel out the nucleus. In our experience this is a bett er alternative than a 23-g needle, as suggested by the authors, to wheel out the nucleus. The needle is a sharp instrument; it can damage the surrounding structure including the wound integrity, specifi cally in the hands of a learner and the sharp edge of the needle could cut the nuclear material rather than wheeling it out.
We do agree with the authors that the Blumenthal technique is innovative, highly eff ective, reproducible in all grades of cataract, involves minimal intraocular manipulation and can be performed in the physiological condition of a closed system. We also agree with Thomas [5] who suggested that ACM allows anyone to learn SICS almost without a learning curve.