Amniotic Membrane Transplantation in Acute Toxic Epidermal Necrolysis: Histopathologic Changes and Ocular Surface Features after 1-Year follow-up

Bilateral panophthalmitis following toxic epidermal necrolysis: A case report

A 70 year old man presented with systemic signs of toxic epidermal necrolysis (TEN) following consumption of diclofenac tablets for a prodromal illness a week back. Ophthalmic evaluation showed no perception of light in both eyes along with lid edema, total corneal sloughing, and pus-filled anterior chamber. An amniotic membrane transplant was planned but within a few hours, both eyes developed panophthalmitis with restricted extraocular movements and mild proptosis and had to be eviscerated. This is perhaps the first case showing such devastating sequelae of TEN.

3D-Printed membrane as an alternative to amniotic membrane for ocular surface/conjunctival defect reconstruction: An in vitro & in vivo study

BACKGROUND

The aim of this study was to evaluate the surgical handling and clinical applicability of a specific 3D-printed membrane design fabricated using a gelatin, elastin and sodium hyaluronate blend for conjunctival reconstruction and compare it with amniotic membrane (AM), which is normally used in such surgeries.

METHODS

3D printing technique was employed to fabricate the membrane based on gradient design. Prior to printing, rheometry was employed to optimize the ink composition. The printed membranes were then fully characterized in terms of physical and mechanical properties. In vitro viability, proliferation and adhesion of human limbal epithelial cells were assessed using MTT assay and scanning electron microscopy (SEM), respectively. Prior to in vivo experiment, surgical handling of each membrane was evaluated by three surgeons. In vivo evaluation was conducted through implanting the gelatin-based membranes and AM on induced conjunctival defects in rabbits (n = 8). Clinical observations, including epithelialization, inflammation severity, scar tissue formation and presence of granulation tissue, were recorded from day 1 through day 28. Histological examination was performed on all enucleated eyes on day 28. In addition to H&E staining, specific stains including Periodic Acid Schiff staining, Masson's Trichrome staining and immuno-histochemical staining for α-SMA were further used to assess goblet cell proliferation, healed sub-epithelial stroma and scar tissue formation and the presence of myofibroblasts, respectively.

RESULTS

Among all the examined compositions, a blend of 8% w/v gelatin, 2% w/v elastin and 0.5% w/v sodium hyaluronate was found to be appropriate for printing. The printed membranes had favorable optical characteristics (colorless and transparent), and the surgical handling was significantly easier compared to AM. Epithelial cells cultivated on the membranes indicated suitable viability and proliferation, and SEM images presented appropriate cell adhesion on the surface of the membranes. Clinical observations suggested similar epithelialization time (approximately 3 weeks) for both the membrane and AM grafted eyes but significantly lower levels of clinical inflammation in the membrane group from day 1 through day 28 (p = 0.01), which is a key advantage of using the printed membranes over the AM. Histological examination showed similar qualities in the healed epithelium in terms of cell morphology and cell layers. However, twice the density of goblet cells per 100 cells was observed in the gelatin-based membrane grafted group. Remnant of the degraded implant was seen in only 3 of the membranes, but in 7 of the AM grafted eyes. Inflammation and granulomatous reaction was significantly higher in sections containing the AM compared to membrane (p < 0.01 and p = 0.01, respectively). α-SMA staining was more evident, but not significantly different from the gelatin-based membrane, for the AM group (p = 0.25).

CONCLUSION

The designed gelatin-based membrane offers the necessary physical and mechanical characteristics needed for successful ocular surface/conjunctival defect construction and may be considered a promising alternative to AM due to a more predictable degradation pattern, higher goblet cell density on the healed epithelium, less inflammation and reduced scar tissue formation.

Modified conjunctival flap as a primary procedure for nontraumatic acute corneal perforation

Objective

Appropriate management of nontraumatic acute corneal perforation is always a challenge even with the many advances in surgical materials and techniques. We reported the outcomes of a case series of acute corneal perforation repair using a newly modified conjunctival flap with amniotic membrane transplant (AMT), fibrin glue, and a bandage soft contact lens (BCL).

Materials and Methods

A total of 13 consecutive referral cases with nontraumatic acute corneal perforation at the University of Washington were reviewed. All open globes were repaired by a combined surgery with a modified conjunctival flap, AMT, fibrin glue, and BCL. Visual acuity, a slit lamp examination, and the patient-reported pain level were collected preoperatively and postoperatively. Subsequent corneal surgeries to improve visual function were also reviewed.

Results

All ocular surfaces of the 13 eyes were stable at postoperative follow-up. Eleven of the 13 patients had the same or worse visual acuity 1 week postoperatively. Nine of the 13 patients achieved better vision 6 months postoperatively. None of the patients developed perioperative or postoperative complications. Five patients with good visual potential underwent further corneal surgeries, including Boston keratoprosthesis and penetrating keratoplasty. The average referral distance was 217 miles and the median number of follow-up visits within 6 months was 4.

Conclusions

The combination of a modified conjunctival flap, AMT, fibrin glue, and a BCL could provide a temporary method to stabilize and secure the integrity of the globe as well as the ocular surface after a nontraumatic acute corneal perforation. This approach allows easy follow-up and preserves the eye for future corneal surgery under optimal conditions.

Comparison of the acute ocular manifestations of Stevens-Johnson syndrome and toxic epidermal necrolysis in Chinese eyes: a 15-year retrospective study

BACKGROUND

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but life-threatening conditions that initially affect the skin and mucous membranes. The aim of this study was to compare the acute ocular manifestations between SJS and TEN.

METHODS

The initial presenting ophthalmic records of patients with either SJS (<30% body surface area involvement) or TEN (> = 30% involvement), who were treated at one tertiary burn center in Hong Kong between 1999 and 2014, were retrospectively analyzed and compared.

RESULTS

A total of 20 SJS and 12 TEN cases were included. All were drug-induced. The patient demographics and treatment received were comparable. Overall, 40% of SJS and 75% of TEN patients had acute ocular surface inflammation. When comparing the two groups, there was a significant difference in the number of cases with mild involvement (5% in SJS, 42% in TEN, p = 0.01), while no statistically significant differences were found (p > 0.05) comparing between the moderate (15% in SJS, 0% in TEN) and severe groups (20% in SJS, 33% in TEN).

CONCLUSIONS

Ocular surface inflammation was common during the acute phase in both SJS and TEN. TEN had a significantly higher number of cases with mild ocular involvement when compared with SJS, but no significant difference between the number of moderate and severe cases between the two groups.

Effects of Autologous Serum Eye Drops on Conjunctival Expression of MUC5AC in Patients With Ocular Surface Disorders

PURPOSE

To assess the effects of autologous serum eye drops on conjunctival expression of the mucin gene MUC5AC by means of quantitative reverse transcription polymerase chain reaction (RT-qPCR).

METHODS

A prospective and comparative interventional case series study of 38 eyes of 19 patients with different ocular surface disorders was performed before and 6 weeks after the treatment with autologous serum eye drops. All patients underwent a complete ophthalmic assessment, including evaluation of the tear film, ocular surface exploration, conjunctival impression cytology (IC), and MUC5AC detection by reverse transcription polymerase chain reaction.

RESULTS

A total of 34 eyes were studied by IC and MUC5AC quantitative reverse transcription polymerase chain reaction before and after treatment with autologous serum. This treatment improved breakup time, conjunctival squamous metaplasia, goblet cell density, and subjective perception in 76.2%, 70.6%, 55.9% and 73.5% of eyes, respectively. Treatment with autologous serum enhanced conjunctival expression of MUC5AC (P = 0.001), although these differences were not statistically significant if data are analyzed patient by patient (P = 0.09). In 13 of 34 eyes (38.2%), we found increased expression of MUC5AC; in 12 eyes (35.3%), no significant changes were found; and in 9 eyes (26.5%), a decreased expression was found. The MUC5AC gene upregulation was related to the conjunctival involvement before treatment and with the improvement in the degree of squamous metaplasia and the increase in the number of goblet cells in IC after treatment (P = 0.001).

CONCLUSIONS

Treatment with autologous serum enhances the conjunctival expression of MUC5AC by increasing the density of goblet cells, mainly in patients with severe conjunctival involvement.