Opioid sensitivity in treated and untreated obstructive sleep apnoea: a prospective cohort study.

BACKGROUND: Opioid administration to patients with obstructive sleep apnoea (OSA) is controversial because they are believed to be more sensitive to opioids. However, objective data on opioid effects in OSA are lacking. We tested the hypothesis that subjects with untreated OSA have increased sensitivity to opioids compared with subjects without OSA, or with OSA treated with continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BIPAP). METHODS: This was a single-centre, prospective cohort study in subjects without OSA (n=20), with untreated OSA (n=33), or with treated OSA (n=21). OSA diagnosis was verified using type III (in-home) polysomnography. Subjects received a stepped-dose remifentanil infusion (target effect-site concentrations of 0.5, 1, 2, 3, 4 ng ml-1). Primary outcome was miosis (pupil area fractional change), the most sensitive opioid effect. Secondary outcomes were ventilatory rate, end-expired CO2, sedation, and thermal analgesia. RESULTS: There were no differences in miosis between untreated OSA subjects (mean=0.51, 95% confidence interval [CI] 0.41-0.61) and subjects without OSA (mean=0.49, 95% CI 0.36-0.62) (mean difference=0.02, 95% CI -0.18 to 0.22); between treated OSA subjects (mean=0.56, 95% CI 0.43-0.68) and subjects without OSA (difference=0.07, 95% CI -0.16 to 0.29); or between untreated OSA and treated OSA (difference=-0.05, 95% CI -0.25 to 0.16). There were no significant differences between subjects without OSA, untreated OSA, and treated OSA in ventilatory rate, end-expired CO2, sedation, or thermal analgesia responses to remifentanil. There was no relationship between OSA severity and magnitude of opioid effects. CONCLUSIONS: Neither obstructive sleep apnoea nor obstructive sleep apnoea treatment affected sensitivity to the miotic, sedative, analgesic, or respiratory depressant effects of the opioid remifentanil in awake adults. These results challenge conventional notions of opioid effects in obstructive sleep apnoea. CLINICAL TRIAL REGISTRATION: NCT02898792 (clinicaltrials.gov).

Pharmacological management of intra-operative miosis during cataract surgery.

Cataract surgery requires a well-dilated and stable pupil for a good outcome. Unexpected pupillary constriction during surgery increases the risk of complication. This problem is more pronounced in children. There are now pharmacological interventions that help tackle this unforeseen happening. Our review discusses the simple and quick options available to a cataract surgeon when faced with this dilemma. As cataract surgical techniques continue to improvise and get faster, an adequate pupil size is of paramount importance. Various topical and intra-cameral drugs are used in combination to achieve mydriasis. Despite good pre-operative dilation, the pupil can be quite unpredictable during surgery. Intra-operative miosis limits the field of surgery and increases the risk of complications. For example, if the pupil size decreases from 7 mm to 6 mm, this 1 mm change in pupil diameter will lead to a decrease of 10.2 mm2 in the area of surgical field. Making a good capsulorhexis with a small pupil can be a challenge, even for an experienced surgeon. Repeated touching of the iris increases the risk of fibrinous complications. Removal of cataract and the cortical matter becomes increasingly difficult. Intra-ocular lens implantation in the bag also requires adequate dilation. When dealing with challenging cases like lens subluxation, pseudo-exfoliation, and zonular dehiscence, a small pupil further increases the risk and adversely affects the surgical outcome. Hence, achieving and maintaining adequate mydriasis throughout surgery is essential. This review highlights the risk factors for small pupils during surgery and current management strategies.

Harlequin syndrome.

A 56-year-old man presented to the clinic with episodic headaches for several years which had been worsening over a few months prior to the presentation. He described headache as sharp, stabbing pain around the left eye associated with nausea, vomiting, photophobia, and phonophobia lasting for hours associated with flushing on the left side of the face. The picture of his face during these episodes showed flushing of the left side of the face, ptosis of the right eyelid, and miosis (panel A). Flushing in his face would resolve with the abortion of the headache. At the time of presentation to the clinic, his neurological exam was only significant for mild left eye ptosis and miosis (panels B and C). Extensive workup including MRI brain, cervical spine, thoracic spine, lumbar spine, CTA head and neck, and CT maxillofacial was unremarkable. He had tried several medications in the past including valproic acid, nortriptyline, and verapamil without significant benefit. He was started on erenumab for migraine prophylaxis and was given sumatriptan for abortive therapy following which his headaches improved. The patient was diagnosed with idiopathic left Horner's syndrome and his migraines with autonomic dysfunction would present with unilateral flushing opposite to the site of Horner's presenting as Harlequin syndrome [1, 2].

A new intraocular lens marker to guide the implantation of toric intraocular lenses in small and mid-dilating pupils.

Insufficient pupillary dilatation is a significant challenge during cataract surgery, as it increases the risk of various intraoperative complications. Implantation of toric intraocular lenses (TIOL) is particularly difficult in eyes with small pupils, as the toric marks are provided in the periphery of the IOL optic, making the visualization of the same difficult for proper alignment. Attempts at visualizing these marks using a second instrument such as a dialler or iris retractor lead to additional manipulations in the anterior chamber resulting in increased chances of postoperative inflammation and intraocular pressure rise. A new intraocular lens (IOL) marker to guide the implantation of TIOLs in eyes with small pupils is described, which can potentially be beneficial in achieving accurate alignment of toric IOLs in small pupils, without the need for additional manipulations, thus improving safety, efficacy, and success rates of TIOL implantation in these eyes.

A rare case of congenital pupillary abnormality: a case report.

BACKGROUND: Congenital anomalies of the pupil are quite varied, including abnormal size, shape, color, response to stimulus, and function. We are here reporting an unusual case presented with the absence of pupillary opening with folds of iris tissue at the center. Only an extremely small pupil (diameter < 0.5 mm) could be observed during the operation. CASE PRESENTATION: A 15-year-old male patient visited our outpatient clinic due to vision difficulty in his right eye for more than ten years. The best-corrected visual acuity was 2.0 logMAR and 0 logMAR for the right and left eye, respectively. There were amblyopia, astigmatism and constant exotropia in his right eye. Ophthalmic examination of the right eye showed flat iris root, minimal iris pigmentation, and the pupil area was entirely covered by iris tissue. Lens status and fundus evaluation could not be commented. The left eye was found to be within normal limit. Based on ophthalmic examination, the admission diagnosis was given as acorea. Pupilloplasty was performed on the right eye due to the situation that the iris tissue blocked the visual axis, which led to visual impairment and stimulus deprivation amblyopia. However, an extremely small pupil at the center of his pupillary area was observed during the operation. The postoperative course was favorable, and a normal pupil was secured. Hospital discharge diagnosis was given as microcoria, and amblyopia treatment was followed. CONCLUSIONS: We report a rare case of congenital pupillary abnormality. The further diagnosis was given as microcoria, which should be differentiated from acorea. For this kind of pupil disorder which blocks the visual axis, early diagnosis and treatment can help prevent the development of stimulus deprivation amblyopia.

Stormorken Syndrome: A Rare Cause of Myopathy With Tubular Aggregates and Dystrophic Features.

Stormorken syndrome is a rare genetic disorder (MIM 185070) first reported in 1983 with thrombocytopenia, muscle weakness, asplenia, and miosis caused by a mutation of the stromal interaction molecule 1 ( STIM1) gene.1 The muscle weakness is caused by a myopathy with tubular aggregate formation. We report a family in which both child and mother presented with proximal muscle weakness and thrombocytopenia. Histologic, histochemical, and electron microscopy studies were performed on the muscle specimen. It documented accumulation of tubular aggregates and chronic myopathic changes with dystrophic features. Genetic testing revealed that both mother and son carried a missense mutation of c.326A>G in exon 3 of the STIM1 gene, which is novel for Stormorken syndrome. We suggest that patients with unexplained chronic idiopathic thrombocytopenia and proximal weakness have genetic testing for Stormorken syndrome.

Everything is ok on YouTube! Quality assessment of YouTube videos on the topic of phacoemulsification in eyes with small pupil.

OBJECTIVE: Usage of YouTube as an educational tool is gaining attention in academic research. To date, there has been no study on the content and quality of eye surgery videos on YouTube. The aim of this study was to analyze YouTube videos on phacoemulsification in eyes with small pupil. METHODS: We searched for the phrases "small pupil cataract surgery," "small pupil phacoemulsification," "small pupil cataract surgery complications," and "small pupil phacoemulsification complications" in January 2015. Each resulting video was evaluated by all authors, and Krippendorff's alpha was calculated to measure agreement. Videos were classified according to pupil size (small/very small) in the beginning of the surgery, and whether pupillary diameter was large enough to continue surgery safely after pupillary dilation by the surgeon in the video (safe/not safe). Methods of dilatation were also analyzed. Any stated ocular comorbidity or surgical complications were noted. RESULTS: A total of 96 videos were reviewed. No mechanical intervention for pupillary dilatation was performed in 46 videos. Fifty-eight operated eyes had no stated ocular comorbidity. Ninety-five operations ended successfully without major complication. There was fair agreement between the evaluators regarding pupil sizes (Kα = 0.670) but poor agreement regarding safety (Kα = 0.337). CONCLUSIONS: YouTube videos on small pupil phacoemulsification have low complication rates when compared to the literature, although no reliable mechanical dilatation methods are used in almost half of these videos. Until YouTube's place in e-learning becomes clearer, we suggest that viewers be cautious regarding small pupil phacoemulsification videos on YouTube.

Outcomes of sphincterotomy for small pupil phacoemulsification.

PURPOSE: Sphincterotomy, an alternative to iris hooks or pupil stretching, is a technique that can aid in small pupil phacoemulsification. The incidence of post-operative complications of this procedure, however, has not been studied. Our study evaluates the post-operative outcomes of phacoemulsification surgery with adjunctive pupillary sphincterotomy. METHODS: We conducted a retrospective review of case notes and Medisoft ® electronic record of patients that had undergone simultaneous sphincterotomy, phacoemulsification and intraocular lens (IOL) implantation by a single surgeon between March 2012 and February 2017. Our main outcome measures were post-operative ocular hypertension (IOP > 21 mmHg), uveitis and cystoid macular oedema (CMO). RESULTS: A total of 114 eyes of 114 patients were included in this study. The mean age was 81.2 years (range: 26-100). All patients had uncomplicated surgery. Transient (<1 month) ocular hypertension developed in five (4%) eyes. Sustained ocular hypertension (>1 month) occurred in one (1%) eye, which had pre-existing glaucoma. All four (4%) eyes that developed a persistent uveitis (>1 month) resolved with topical therapy except for one eye with a history of uveitis. The 6 (5%) eyes that developed CMO had a history significant for uveitis (n = 4), diabetic macular oedema (n = 1) and epiretinal membrane (n = 1). All CMO maculae resolved to their baseline. CONCLUSION: The incidence of post-operative complications following uncomplicated phacoemulsification and IOL implantation with pupillary sphincterotomy is low. The most important predisposing factors for development of a complication are ocular co-morbidities such as glaucoma, uveitis and the presence of a macular pathology.

Cataract surgery in small pupils.

This paper presents the review of historical aspects and the current state-of-the-art in various pupil dilatation methods to be used in cataract surgery. The surgical algorithm in managing small pupil cases should include topical and intraocular mydriatics, appropriately selected viscosurgical device and mechanical dilatation with instruments, iris hooks, and/or pupil expanders.

B-HEX pupil expander: Pupil expansion redefined.

The B-HEX® Pupil Expander (Med Invent Devices) is a disposable 6.5 mm flexible hexagonal device with notches at corners and flanges at sides. Alternate flanges with positioning holes are tucked under the iris to engage the notches to the margin of the pupil to provide a 5.5 mm expanded pupil. Unlike devices with scrolls or pockets which require an injector to avoid snagging the incision, the preloaded B-HEX is inserted and removed through a 1 mm or larger incision using a manipulator or 23-gauge micro-forceps. The thin profile and uniplanar design allow unhindered instrument movement during phacoemulsification, cortical cleaning, and intraocular lens implantation. The B-HEX is safely used even after capsulorhexis since the thin uniplanar notches are directly visualized to avoid the capsule margin. It is useful in coaxial phacoemulsification, coaxial sub 2.00 mm micro incision cataract surgery (MICS), biaxial 1.5 mm MICS, femtosecond laser assisted cataract surgery (FLACS), small pupil pars plana vitrectomy, and shallow anterior chamber eyes.

Capsule-Fixated Intraocular Lens Implantation in Small Pupil Cases.

PURPOSE: To describe a new technique for implantation of capsule-fixated intraocular lenses (IOLs) (FEMTIS; Oculentis, Berlin, Germany) in patients with small pupils. METHODS: In 4 eyes with small pupils, an anterior capsule-fixated IOL was implanted into the capsular bag after femtosecond laser treatment. The two large and two small flaps of the IOL were elevated to the front of the iris and the anterior capsule. Finally, the iris was flipped over the flaps to ensure a fixation of the capsule inside of the capsulotomy. RESULTS: In all cases, the implantation of anterior capsule-fixated IOLs was possible. No complications occurred during surgery or within the first months after surgery. CONCLUSIONS: With the described technique, capsulefixated IOLs can be implanted in eyes with small pupil easily and safely. This type of IOL has great potential to improve the refractive outcome by better prediction of the postoperative IOL position and eliminating IOL rotation after cataract surgery. [J Refract Surg. 2017;33(8):568-570.].

[Differentiated approach to hybrid phacoemulsification in small pupils].

AIM: to develop a differentiated approach to hybrid phacoemulsification (PE) in small pupils. MATERIAL AND METHODS: Modified hybrid PE was performed in 119 patients (130 eyes) with conditionally small pupils (preoperative dilated pupil diameter of less than 5.5 mm). RESULTS: A differentiated approach to hybrid PE has been developed and tested in patients with poor preoperative mydriasis. CONCLUSIONS: Small rigid pupils are considered a relative contraindication for hybrid PE. Developed modifications enable less surgical trauma and changes in efficient exposure time, while the latter is usually increased in standard PE in patients with poor preoperative pupil dilation.

Small pupil and cataract surgery.

PURPOSE OF REVIEW: Presence of a small pupil is still considered a major challenge for cataract surgeons. Appropriate mydriasis and maintaining it is of paramount importance to prevent potential serious complications. Recently, more interventions and instruments are available for the cataract surgeons to deal with these challenging cases. The intention of this review is to discuss the preoperative and intraoperative considerations and techniques for cataract surgery in small pupil and related conditions and to discuss new developments in management of small pupil in femtosecond laser-assisted cataract surgery. RECENT FINDINGS: There are new techniques and pharmaceuticals available to cataract surgeons in the setting of small pupil. Intracameral ketorolac may soon be available to maintain mydriasis and to control pain and inflammation. Malyugin ring has been added to pupil expansion rings and has already been used for small pupil in different settings. In femtosecond laser-assisted cataract surgery, presence of a small pupil can now be managed by applying intracameral mydriatics and intraocular devices successfully. SUMMARY: Accurate preoperative examinations adjunct with intraoperative use of appropriate pharmacologic and mechanical devices can yield favorable outcomes in cataract surgery with a small pupil.

Secondary hemicrania continua: Case reports and a literature review.

Hemicrania continua (HC) is an indomethacin responsive primary headache disorder. Secondary or symptomatic HC is associated with another neurological or non-neurological disease. We report three patients with secondary HC. We also review the literature to identify the clinical predictors of an underlying disease entity. Intracranial structural lesion, head and neck vessel pathology, and carcinoma lung should be suspected in every patient. The factors that may suggest a secondary pathology are: elderly age, male sex, smoking habit, constitutional symptoms, symptoms related to respiratory system, frequent and short-lived exacerbation, nocturnal exacerbation, HC evolving from remitting form, recent neck and/or head trauma, miosis, elevated ESR, and fading effect of indomethacin. We recommend MRI brain in all the patients presenting with HC or HC like headache. Angiography and CT chest are two other investigations that may be supplemented in patients with high risk for head/neck vessel pathology and carcinoma lung.

Cataract surgery (phacoemulsification) in difficult cases.

UNLABELLED: By presenting three cataract surgeries, we discuss the difficulties of the interventions and the key moments. Case I: Mature cataract surgery on a patient with corneal opacities (maculas). Case II: Posterior polar cataract. Case III: Small pupil, shallow anterior chamber (dilating with Malyugin ring). CONCLUSIONS: The surgery of a mature cataract on an eye with corneal opacities can be performed by a surgeon with enough experience. The final visual acuity depends on the clarity of the center of the cornea. During the operation of a posterior polar cataract we have to be prepared to the rupture of the posterior capsule, which is more frequent than in other cases. These interventions are better to be made in centers with posterior pole surgery capabilities. The Malyugin ring is a novel PMMA device, which dilates the pupil, creating decent conditions for a cataract surgery This device can be inserted and pulled out through a standard 2,8 mm incision.