Transcript The Cambridge Prophylactic Cryotherapy Protocol Size: 7.2 MB

Prevention of retinal detachment in Stickler syndrome: the Cambridge Prophylactic Cryotherapy protocol (2848)
Gregory S Fincham,1 Laura Pasea,2 Christopher Carroll,3 Annie M McNinch,1,4 Arabella V Poulson,1 Allan J Richards,4,5 John D Scott,1 Martin P Snead.1,4
1Vitreoretinal
Service, Cambridge University NHS Foundation Trust, Addenbrooke’s Hospital, 2Centre for Applied Medical Statistics, University of Cambridge, 3School of Health and Related Research,
University of Sheffield, 4Department of Pathology, University of Cambridge, United Kingdom, 5Regional Molecular Genetics Laboratory, Cambridge University NHS Foundation Trust, Addenbrooke’s Hospital.
Stickler syndrome (MIM#108300)
•Progressive arthro-ophthalmopathy is the leading cause of
childhood and inherited retinal detachment (RD).
•Patients present with features illustrated in figures 1 to 6.
•Type 1 Stickler syndrome patients carry the greatest risk of
RD following giant retinal breaks at the ora serrata.
Hypothesis
Prophylactic cryotherapy to the ora serrata, where giant
retinal breaks are predicted to occur, would reduce the rate of
RD in type 1 Stickler syndrome.
Methods
28 year old male
4. Megaglobus and
3. Facial dysmorphia
2. Midline palatal
1. Spondyloepiphyseal
congenital myopia
and hearing loss
cleftingManagement:
dysplasia
•Intravenous Dextrose infusion with rates up to 250mls/hr of 20% Dextrose
5. Pathognomonic type
1 vitreous phenotype
6. Oral giant retinal
tear and detachment
•Dietary intervention with frequent meals and corn starch
•Diazoxide – intolerant leading to hyponatraemia, oedema and nausea
•Octreotide/glucagon intravenously – in order to replace counter-regulatory hormones
Patients were divided into four groups for comparison before
1
•Subcutaneous
Octreotide
hypoglycaemia
worsened
and after individual patient matching protocols:
•Bilateral prophylaxis – cryoprophylaxis to both eyes (n=194)
•Prednisolone – developed fluid retention
•Bilateral control – no previous cryoprophylaxis (n=229)
•Hepatic
Arterial
Embolisation
(HAE)
performed
twice
with
initial
improvement
(post-procedure
insulin
29
pmol/l),
but
relapsed
after
4
weeks.
•Unilateral prophylaxis – unilateral cryoprophylaxis following
fellow eye RD (n=104)
•Unilateral control – no unilateral cryoprophylaxis following
fellow eye RD; subgroup of bilateral control (n=64)
Figure 11. Kaplan-Meier plot of unmatched
Figure 7. Prevalence of retinal detachment in
Figure 9. Kaplan-Meier plot of unmatched
unilateral control versus prophylaxis group
control versus prophylaxis groups
bilateral control versus prophylaxis group
Results
•The prevalence of RD was significantly reduced in all
groups receiving prophylaxis (see fig. 7)
•Sex-adjusted hazard ratios were significantly higher in all
groups who did not receive prophylaxis (see fig. 8)
•Kaplan-Meier survival analysis demonstrated significant
benefit to all groups receiving prophylaxis (see figs. 9 – 12).
•Cryoprophylaxis given according to the Cambridge
Prophylactic Cryotherapy protocol caused no long-term side
effects.
Conclusion
In the largest global cohort of type 1 Stickler syndrome
patients published to date, all analyses indicate that the
Cambridge Prophylactic Cryotherapy protocol is safe and
markedly reduces the rate of retinal detachment.
Correspondence: [email protected]
Figure 8. Hazard ratios: effect without prophylaxis
and 95% confidence intervals (*sex-adjusted)
Figure 10. Kaplan-Meier plot of matched
bilateral control versus prophylaxis group
Figure 12. Kaplan-Meier plot of matched
unilateral control versus prophylaxis group
Addenbrooke’s Hospital
Rosie Hospital