Intraocular Pressure, Intracranial Pressure, Translaminar Pressure Difference and Related Factors in Primary Open Angle Glaucoma
Actors Affecting in Primary Open Angle Glaucoma
Abstract
This study aims to investigate and compare the relationship between intracranial pressure (ICP), intraocular pressure (IOP) and translaminar pressure difference (TLPD) in high-tension glaucoma (HTG) patients and healthy individuals. Newly diagnosed HTG patients and healthy subjects without ocular comorbidities were recruited. All participants underwent blood pressure, heart rate, body weight, height and comprehensive ocular examinations, including best-corrected visual acuity, IOP measurement, optic nerve head assessment, peripapillary retinal nerve fibre layer and macular imaging, visual field testing, axial length and central corneal thickness measurements. ICP was estimated using the formula:
Cerebrospinal fluid pressure (mmHg) = (0.44×x Body Mass Index (kg/m2)) + (0.16 x× Diastolic Blood Pressure (mmHg))-(0.18 x Age (years)) - 1.91. TLPD was calculated by subtracting the estimated ICP from the IOP. Compared to healthy subjects, HTG patients had significantly higher median IOP [26.00 (24.00-34.00) mmHg vs. 13.00 (10.00-14.00) mmHg], lower median ICP [8.19 (6.86-10.28) mmHg vs. 11.31 (8.91-12.36) mmHg], and higher median TLPD [18.64 (15.27-26.19) mmHg vs. 1.72 (0.27-4.62) mmHg]. There was no correlation between IOP and ICP; however, IOP was significantly correlated with TLPD in both groups, HTG (r = 0.911, p < 0.001) and non-glaucomatous (r = 0.758, p < 0.001). In healthy subjects, TLPD was moderately and negatively correlated with ICP (r = -0.525, p = 0.012). The lower ICP observed in HTG patients suggests that ICP may be associated with the development of glaucoma. Further research is needed to explore the impact of ICP on glaucoma progression and disease management.
Keywords :
Cerebrospinal fluid pressure; glaucoma; intracranial pressure; intraocular pressure; primary open angle glaucoma; translaminar pressure difference,
Abstrak
Kajian ini bertujuan untuk menyiasat dan membandingkan hubungan antara tekanan intrakranium (ICP), tekanan bola mata (IOP) dan perbezaan tekanan translamina (TLPD) dalam kalangan pesakit yang menghidapi penyakit glaukoma bertekanan tinggi (HTG) dan populasi normal. Pesakit yang baru menghidapi HTG dan subjek normal tanpa penyakit mata telah direkrut untuk kajian ini. Semua peserta kajian menjalani ukuran tekanan darah, kadar denyutan jantung, berat badan, ketinggian dan pemeriksaan mata secara menyeluruh termasuk ujian tahap penglihatan, ukuran IOP, pemeriksaan cakera saraf optik, analisa ketebalan saraf mata di sekeliling cakera saraf optik dan peta ketebalan makula, ujian medan visual ukuran panjang bola mata serta ketebalan tengah kornea. ICP telah dikira menggunakan formula ICP (mmHg) = (0.44 x Indeks jisim badan (kg/m2)) + (0.16 x Tekanan darah diastolik (mmHg))-(0.18 x Umur (tahun)) - 1.91. TLPD diperoleh melalui hasil tolak ICP daripada IOP. Pesakit HTG mempunyai median IOP lebih tinggi [26.00 (24.00-34.00) mmHg vs. 13.00 (10.00-14.00) mmHg], median ICP lebih rendah [8.19 (6.86-10.28) mmHg vs. 11.31 (8.91-12.36) mmHg], median TLPD lebih tinggi [18.64 (15.27-26.19) mmHg vs. 1.72 (0.27-4.62) mmHg] berbanding dengan subjek normal. Tiada kolerasi diperhatikan antara IOP dan ICP. Walau bagaimanapun, IOP didapati mempunyai kolerasi dengan TLPD dalam kedua-dua kumpulan pesakit HTG (r = 0.911, p < 0.001) dan subjek normal (r = 0.758, p < 0.001). TLPD mempunyai korelasi negatif dengan ICP (r= -0.525, p=0.012) dalam kalangan subjek sihat. ICP yang lebih rendah di kalangan pesakit HTG menunjukkan kemungkinan ICP memainkan peranan dalam perkembangan glaukoma. Kajian lanjut perlu dijalankan bagi menyiasat kesan ICP terhadap perkembangan glaukoma dan juga pengurusan bagi rawatan penyakit tersebut.
Kata Kunci :
Glaukoma; glaukoma sudut terbuka primer; perbezaan tekanan translamina; tekanan bola mata; tekanan cecair serebrospinal; tekanan intrakranium,
Correspondance Address
Jemaima Che-Hamzah. Department of Ophthalmology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Bandar Tun Razak, 56000 Cheras, Kuala Lumpur, Malaysia. Tel: +603-91455984 E-mail: jemaima@hctm.ukm.edu.my
