Peripapillary retinal nerve fiber layer [RNFL] thickness measurements by topcon SD-OCT in myopic patients

Objective: To evaluate the effect of low-to-moderate myopia on peripapillary retinal nerve fiber layer [RNFL] thickness measured by Topcon SD optical coherence tomography [OCT]. Study Design: Cross-sectional study. Place and Duration of Study: Ophthalmology Department, Shifa Foundation Falahee Clinic, over a period of one year starting from June 2015

Methodology: A total of 43 eyes of 43 patients, having mild to moderate myopic refractive error, were enrolled in the study. Refractive error/spherical equivalent was calculated. RNFL thickness was obtained from all four peripapillary quadrants: temporal, superior, nasal, and inferior; and 12 sub-quadrants using Topcon SD OCT. Pearson correlation coefficients [r] were calculated to evaluate relationships between the RNFL thickness and spherical equivalent [SE] before and after adjustment for ocular magnification

Results: The study included 51.2% females and 48.8% males. Mean age was 30.9 +/- 6.45 years. Mean axial length was 24.25 +/- 0.91 mm. Mean SE was -3.25 +/- 1.93 DS. Mean of average RNFL thickness [with Littmann's correction] was 97.28 +/- 8.15 microm. Correlation analysis among all subjects showed that the average, mean nasal quadrant, upper nasal, and inferonasal sub-quadrant RNFL thickness had positive correlation with spherical equivalent [r = 0.31, p = 0.045]. However, correction of the magnification effect by applying Littmann formula eliminated this effect

Conclusion: In low-to-moderate myopia, RNFL measurements vary with refractive error of the eye. Since ocular magnification significantly affects the RNFL measurement, it should be considered in diagnosing glaucoma

Central corneal thickness and its relationship to intra-ocular and epidmiological determinants

Objective: To measure central corneal thickness in Pakistani population and determine its relationship to intra-ocular pressure, age, gender and ethnicity

Study Design: Cross-sectional observation study

Place and Duration of Study: Pakistan Institute of Medical Sciences, Islamabad, Pakistan, between December 2013 and February 2015

Methodology: The right eyes of 1000 cases [496 males and 504 females] were recruited for this study. Inclusion criteria were Pashtun or Punjabi ethnicity, intra-ocular pressure < 22 mmHg, gonioscopically open angles, cup-disk-ratio < 0.5, and age matched normal visual fields. Cases with prior ocular surgery, contact lens use, corneal pathologies, myopia or hypermetropia > +/- 3.0 diopters, astigmatism of > +/- 1.0 diopters were excluded. Central corneal thickness was measured using a TopCon non-contact specular microscope. Intra-ocular pressure was measured using Goldmann applanation tonometer. Frequency distribution, test of significance, and regression analysis was carried out using Statistical Package for Social Sciences version 20.0

Results: Mean age was 47.31 +/- 11.78 years. Ethnic composition was 51.6% [n=516] Pashtun and 48.4% [n=484] Punjabi. The mean central corneal thickness was 503.96 [ +/- 12.47] urn, while the mean intra-ocular pressure was 15.61[ +/- 2.68] mmHg. Regression analysis showed a significant association between central corneal thickness and intra-ocular pressure [p=0.00] and age [p=0.00]. A +/- 100 u change in central corneal thickness was associated with change in IOP of +/- 3.30 mmHg, whereas central corneal thickness decreased by 0.12 urn per year. No significant association could be established between central corneal thickness and ethnicity [p=0.19]

Conclusion: Central corneal thickness of the studied races was comparable to non-Caucasians which affects intra-ocular pressure measurements, and decreases with increasing age. No relationship was observed between central corneal thickness and ethnicity or gender

Use of box simulators for improving intraoperative laparoscopic skills: an essential tool for the surgeon in training

To compare the improvement of intraoperative laparoscopic skills by measuring GOALS score between residents who have undergone simulator training with those who have not received any simulator training. A randomized controlled trial. Department of Surgery, Services Hospital, Lahore, from August 2013 to February 2014. Thirty residents belonging to year 1, 2 and 3 were included in the study. They were randomly divided into 2 groups. Both groups had a baseline evaluation with GOALS score while performing dissection of gallbladder from liver bed during laparoscopic cholecystectomy. Group-A underwent formal training on simulators whereas group-B did not receive any formal training on simulators. After 6 months, a repeat evaluation was done again by measuring GOALS score while performing gallbladder dissection. Baseline GOALS scores of both the groups were similar. Group-A baseline score was 7.66 +/- 0.93 and group-B score was 7.46 +/- 1.04 [p = 0.585]. However repeat scores for group-A showed a significant improvement [an increase of 7.16 +/- 1.48 to 14.76 +/- 1.67, p < 0.001] from baseline scores. Residents in group-B improved their scores by 2.30 +/- 0.99 to 9.76 +/- 0.79 [p < 0.001]. When inter group comparison was done the second score of group-A was significantly higher than that of group-B [14.76 +/- 1.67 vs. 9.76 +/- 0.79, p < 0.001]. Inter-rater reliability was moderately significant [Kappa 0.540]. Training on laparoscopic simulators results in significant improvement of intraoperative laparoscopic skills

Malignant Melanoma: presentation as a primary retroperitoneal tumor

This is a case report of an extremely rare primary malignant melanoma presenting in the retroperitoneum of a 30 years old female. She was operated in a District General Hospital with a presumptive diagnosis of hydatid cyst of right lobe of liver. The patient bled profusely on exploration and the surgeon packed the abdomen and referred her to our emergency, where she was received in shock. After resuscitation she was operated on the next available list and was found to have a very vascular, pigmented, retroperitoneal mass measuring 10-x 12-cm lying in front of the infrarenal IVC pushing the duodenum towards the midline. It was completely excised. Histopathology showed it to be a malignant melanoma. Upon subsequent examination and extensive workup, no evidence of a primary malignant melanoma was found. There was no past history of a melanoma which may have regressed spontaneously or excised. After extensive search of literature we could not find another report of a primary retroperitoneal melanoma

Critical factors in determining mortality from penetrating abdominal vascular trauma: the Mayo Hospital experience

Mayo Hospital Lahore is a big and busy trauma center in Pakistan that receives a substantial number of patients with penetrating abdominal trauma. Vascular injuries in these patients are not uncommon. They are difficult to repair and are usually associated with a high mortality. The purpose of this study was to review treatment principles, complications and factors affecting the outcome variables in our setup in these cases, the main outcome variable being survival. Complete medical records of 411 patients with penetrating abdominal injuries, operated in our emergency over a four years period [January 1996 - December 1999], were reviewed. Amongst these 57[13.86%] had significant abdominal vascular injuries. The commonest afflicting agents were firearms [81%]. The overall mortality was 31.5%. The highest mortality was associated with retro-hepatic vena caval injuries [66.6%]. Very high mortality rates were seen in patients who were admitted with un-recordable blood pressure [72.2%] and in patients who had combined arterial and venous injuries i.e. more than one abdominal vascular injury [42.8%]. Mortality seems to be directly related to the site of the vascular injury [high for supra-renal / retro-hepatic vena caval injuries], the presence of shock on admission, free bleeding and the lack of retro-peritoneal tamponade at the time of surgery, and the presence of additional vascular injuries. The major cause of death in our patients was profound shock due to uncontrolled bleeding. Early diagnosis, prompt intervention and effective management could result in improved salvage rates

Complication of eye shield

A case of postoperative ocular trauma is reported in which a patient was wearing a rigid eye shield. The case illustrates the potential for injury from these devices through various mechanisms, which are discussed. It also emphasizes the importance of positioning the eye shield correctly and in educating the patient on its use